Development of low cost fuselage frames by resin transfer molding - Salek, Hasan; Trudeau, Paul (SAE Technical Paper, 2013)
This paper presents work on the development of a low cost fuselage C-frame for aircraft primary structure using a Light Resin Transfer Molding (RTM) process. Compared to labor intensive hand layup prepreg technologies, Light RTM offers some substantial advantages by reducing infrastructure requirements such as hydraulic presses or autoclaves. Compared to Prepreg, Light RTM tooling creates two finished surfaces, which is an advantage during installation due to improved dimensional accuracy. The focus of this work was to develop means of achieving high fiber volume fraction structural frames using low cost tooling and a low volume manufacturing strategy. In this case a three piece Light RTM mold was developed using an internal mandrel. To achieve the strength requirements, a combination of crimped and non-crimped fabrics were selected for the reinforcing preform. This made it possible to reduce the number of flat patterns by more than 8 times, saving layup time compared to the prepreg counterpart. The processing parameters were optimized to reduce cycle time. Permeability, in-situ resin cure monitoring and coefficient of thermal expansion tests were used in the numerical simulations. Process induced deformation and resin flow simulations were completed to provide input for the tool design. In addition to all the process improvements, risk mitigation testing was completed to validate the design allowables. This work was a collaborative effort by an integrated product development team consisting of design, stress and materials and processing functions.
Keywords: Airframes; Fuselages; Molding; Resins

The near wake of a freely flying European starling - Kirchhefer, Adam J.; Kopp, Gregory A.; Gurka, Roi (Physics of Fluids, 2013)
The wake of a freely flying European starling (Sturnus vulgaris) has been measured using high speed, time-resolved, particle image velocimetry, simultaneously with high speed cameras which imaged the bird. These have been used to generate vector maps that can be associated with the bird's location and wing configuration in the wind tunnel. Time series of measurements have been expressed as composite wake plots which depict segments of the wing beat cycle for various spanwise locations in the wake. Measurements indicate that downwash is not produced during the upstroke, suggesting that the upstroke does not generate lift. As well, the wake velocities imply the presence of streamwise vortical structures, in addition to tip vortices. These two characteristics indicate similarities between the wake of a bird and the wake of a bat, which may be general features of the wakes of flapping wings.

Wind-tunnel investigations of an inclined stay cable with a helical fillet - Larose, Guy L.; D'auteuil, Annick; Bosch, Harold R.; Jakobson, Jasna B.; Macdonald, John H. G. (European and African Conferences on Wind Engineering, 2013)
An experimental study of the effect of adding a helical fillet to the surface of a stay cable in relation to its response to wind-induced excitation was carried out on a 1:1 scale free-to-respond sectional model at the National Research Council Canada. The experiments revealed that a stay cable with a helical fillet inclined at 60◦ to the flow can experience wind induced vibrations with large amplitudes in smooth or turbulent flow for a low level of structural damping. The oscillations observed appeared to be self-limited in amplitude and could be mitigated with an increase of structural damping. The experiments revealed also that the aerodynamic forces at the source of the vibrations were highly sensitive to a rotation of the cable model about its axis. Measurements of the external diameter of the smooth cable model have shown a maximum eccentricity equivalent to 1% of the mean diameter which appeared to be sufficient to influence the aerodynamics of the cable model, even with the helical fillet in place.

Using a systems dynamics model to assess skill level impact - Urbanic, R. J.; Bacioiu, G. M. (2013 Industrial and Systems Engineering Research Conference, 2013)
Research activities have been performed to identify areas of complexity related to the product, process or operational tasks. The developed framework decouples the manufacturing complexity aspects using a systematic approach to decompose the problem into key impact factors. The result of this model provides insight into the system sensitivities when considering human characteristics. However, the model is a static model. Skill levels improve with experience and repetition. The actors within a system may have different levels of skills and knowledge, and how and where these resources are utilized within a system will impact inventory and throughput. As well, people have different learning characteristics. Both these static and dynamic elements impact the system performance. This research presents a systems dynamics model that contains production rules and rules to evaluate the impact of human skill level variations based on the complexity of a task / set of tasks. The impact of positioning a set of personnel with different skill levels on different positions in an assembly line is explored.
Keywords: cognition and reasoning; performance evaluation; human subjects; skills

Use of QDOT photoluminescence for codification and authentication purposes - Chang, Shoude (Luminescence, 2013)

Transcriptome profiling identifies candidate genes associated with the accumulation of distinct sulfur γ-glutamyl dipeptides in Phaseolus vulgaris and Vigna mungo seeds - Liao, Dengqun; Cram, Dustin; Sharpe, Andrew G.; Marsolais, Frédéric (Frontiers in Plant Science, 2013)
Common bean (Phaseolus vulgaris) and black gram (Vigna mungo) accumulate γ-Glutamyl-S-methylcysteine and γ-Glutamyl-methionine in seed, respectively. Transcripts were profiled by 454 pyrosequencing data at a similar developmental stage coinciding with the beginning of the accumulation of these metabolites. Expressed sequence tags were assembled into Unigenes, which were assigned to specific genes in the early release chromosomal assembly of the P. vulgaris genome. Genes involved in multiple sulfur metabolic processes were expressed in both species. Expression of Sultr3 members was predominant in P. vulgaris, whereas expression of Sultr5 members predominated in V. mungo. Expression of the cytosolic SERAT1;1 and -1;2 was approximately fourfold higher in P. vulgaris while expression of the plastidic SERAT2;1 was twofold higher in V. mungo. Among BSAS family members, BSAS4;1, encoding a cytosolic cysteine desulfhydrase, and BSAS1;1, encoding a cytosolic O-acetylserine sulphydrylase were most highly expressed in both species. This was followed by BSAS3;1 encoding a plastidic β-cyanoalanine synthase which was more highly expressed by 10-fold in P. vulgaris. The data identify BSAS3;1 as a candidate enzyme for the biosynthesis of S-methylcysteine through the use of methanethiol as substrate instead of cyanide. Expression of GLC1 would provide a complete sequence leading to the biosynthesis of γ-Glutamyl-S-methylcysteine in plastids. The detection of S-methylhomoglutathione in P. vulgaris suggested that homoglutathione synthetase may accept, to some extent, γ-Glutamyl-S-methylcysteine as substrate, which might lead to the formation of S-methylated phytochelatins. In conclusion, 454 sequencing was effective at revealing differences in the expression of sulfur metabolic genes, providing information on candidate genes for the biosynthesis of distinct sulfur amino acid γ-Glutamyl dipeptides between P. vulgaris and V. mungo.
Keywords: sulfur metabolism; gamma-glutamyl dipeptides; S-methylcysteine; Vigna mungo; Phaseolus vulgaris; developing seed; 454 transcriptome sequencing

Thermal control of continuous resistance welding of fiberglass laminates for automated manufacturing - Mantegh, Iraj; Zammar, Imad; Ahmadi, Mojtaba; Yousefpour, Ali (18th Design for Manufacturing and the Life Cycle Conference / 2013 ASME/IEEE International Conference on Mechatronic and Embedded Systems and Applications, 2013)
Resistance welding is an alternative process to mechanical fastening and adhesive bonding in joining thermoplastic composites. The resistance welding procedure involves the Joule heating of a heating element located between two adjoining thermoplastics. The application of heat causes the material in the interface between two surfaces to melt. The current stops then and the interfacing surfaces bound under a compaction pressure, while cooling. This results in a fusion bond between the two components. A fuzzy logic controller is designed and implemented in real-time using the temperature estimate as the feedback signal. The result is a controller capable of maintaining the weld temperature within 10% of the reference temperature.
Keywords: welding; laminates; manufacturing; glass reinforced plastics

Therapeutic potential of amniotic fluid-derived cells for treating the injured nervous system - Rennie, Kerry; Haukenfrers, Julie; Ribecco-Lutkiewicz, Maria; Ly, Dao; Jezierski, Anna; Smith, Brandon; Zurakowski, Bogdan; Martina, Marzia; Gruslin, Andrée; Bani-Yaghoub, Mahmud (Biochemistry and Cell Biology, 2013)
There is a need for improved therapy for acquired brain injury, which has proven resistant to treatment by numerous drugs in clinical trials and continues to represent one of the leading causes of disability worldwide. Research into cell-based therapies for the treatment of brain injury is growing rapidly, but the ideal cell source has yet to be determined. Subpopulations of cells found in amniotic fluid, which is readily obtained during routine amniocentesis, can be easily expanded in culture, have multipotent differentiation capacity, are non-tumourigenic, and avoid the ethical complications associated with embryonic stem cells, making them a promising cell source for therapeutic purposes. Beneficial effects of amniotic fluid cell transplantation have been reported in various models of nervous system injury. However, evidence that amniotic fluid cells can differentiate into mature, functional neurons in vivo and incorporate into the existing circuitry to replace lost or damaged neurons is lacking. The mechanisms by which amniotic fluid cells improve outcomes after experimental nervous system injury remain unclear. However, studies reporting the expression and release of neurotrophic, angiogenic, and immunomodulatory factors by amniotic fluid cells suggest they may provide neuroprotection and (or) stimulate endogenous repair and remodelling processes in the injured nervous system. In this paper, we address recent research related to the neuronal differentiation of amniotic fluid-derived cells, the therapeutic efficacy of these cells in animal models of nervous system injury, and the possible mechanisms mediating the positive outcomes achieved by amniotic fluid cell transplantation.
Keywords: amniotic fluid; brain injury; cell-based therapy; gap junctions; micro-RNAs; stem cells; liquide amniotique; lésion cérébrale; thérapie cellulaire; jonctions communicantes; micro ARN; cellules souches

Theoretical analysis of high order harmonic generation from bulk crystals - Vampa, Giulio; Mcdonald, Chris R.; Orlando, Gianfranco; Klug, Dennis D.; Corkum, Paul B.; Brabec, Thomas (Frontiers in Optics 2013, 2013)
We investigate High order Harmonic Generation in crystals exposed to intense mid-IR light and find that the interband polarization build-up dominates. In the Keldysh limit, we derive an intuitive picture of HHG in solids.

The Space Geodesy Project and radio frequency interference characterization and mitigation - Hilliard, Lawrence M.; Beaudoin, C.; Corey, B. E.; Tourain, C. L.; Petrachenko, B.; Dickey, John (2013 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), 2013)
The Space Geodesy Project (SGP) development by NASA is an effort to co-locate the four international geodetic techniques Satellite Laser Ranging (SLR) and Lunar Laser Ranging (LLR), Very Long Baseline Interferometry (VLBI), Global Navigation Satellite System (GNSS), and Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS) into one tightly referenced campus and coordinated reference frame analysis. The SGP requirement locates these stations within a small area to maintain line-of-sight and frequent automated survey known as the vector tie system. This causes a direct conflict with the new broadband VLBI technique. Broadband means 2-14 GHz, and RFI susceptibility at -80 dBW or higher due to sensitive RF components in the front end of the radio receiver.
Keywords: broadband antennas; radio frequency; navigation; broadband communication; adaptation models

The significance of astrocytic glutathione system in neuroprotection : a potential role for circumin - Sandhu, Jagdeep K.; Sodja, Caroline; Byrd, Angele; Cadieux, Christian; Lanthier, Patricia; Walker, P. Roy; Sikorska, Marianna (Glutathione : biochemistry, mechanisms of action and biotechnological implications, 2013)
Decreased brain content of thiol antioxidant glutathione (GSH) is regarded as an indicator of excessive oxidative stress, which, in turn, is recognized as a contributing factor to the development and progression of several age-related neurodegenerative diseases. Brain GSH is mainly produced by astroglia and their metabolic coupling with neurons allows the latter cells to maintain a sufficient antioxidant defense under physiological conditions. Neurons, however, are very sensitive to GSH depletion; hence any impairment in astrocyte-neuron GSH metabolic interactions, as it may occur in brain pathologies, would render neurons more susceptible to oxidative injuries. This also implies that agents capable of elevating brain GSH level could prove useful as neuroprotectants. In this chapter, we review data that supports these suppositions, generated using human NT2/N neurons and NT2/A astrocytes obtained by differentiation of NT2/D1 cells. Indeed, the results showed that astrocytes rendered neurons more resistant to toxic injuries and supported neuronal survival even in the presence of low GSH levels. They could not, however, support the neurons under chronic GSH depletion. We also tested curcumin, a naturally occurring polyphenol with anti-inflammatory and antioxidant properties, for its ability to alter the GSH levels in NT2/N and NT2/A cells. Since curcumin is insoluble in aqueous media it is difficult to establish convincingly its efficacy. Here we have applied a solubilizing method developed in our laboratory (US patent No. 6,045,826 and 7,645,816; Ubisol technology licensed to Zymes LLC) to produce a water-soluble nano-micellar complex between PSS (polyoxyethanyl -sitosteryl sebacate) and curcumin (WS-Cur) which can be readily tested under any experimental conditions. The data showed that a 24 h treatment with WS-Cur increased GSH levels in both cell types and that this treatment was neuroprotective. Our results add to the growing body of evidence indicating that agents capable of modulating GSH, such as WS-Cur, might prove highly beneficial in the management of oxidative stress-induced neurodegeneration. Furthermore, strategies aimed at modulating and restoring astrocyte function, for example, by increasing GSH, might present new opportunities for repairing and restoring brain function.

The role of the Kramers-Henneberger atom in the higher-order Kerr effect - Patchkovskii, S.; Richter, M.; Morales, F.; Smirnova, O.; Ivanov, M. (2013 Conference on Lasers and Electro-Optics Europe and International Quantum Electronics Conference (CLEO®/Europe-IQEC 2013), 2013)
We present a generalized model for the intensity dependent response of atoms in strong IR laser fields, describing deviations in the nonlinear response at the frequency of the driving field from the standard model (linear Kerr effect + plasma defocusing) based on the formation of the stable KH states. According to our numerical simulations, shaping the driving laser pulse allows one to reveal a prominent resonance structure in the Kerr response of an individual atom, which can only be explained by population transfer into excited KH states.
Keywords: Atomic beams; Atom lasers; Laser modes; Laser excitation; Atomic clocks; Numerical models

The productivity and impact of astronomical telescopes - a bibliometric study for 2007 - 2011 - Crabtree, Dennis R. (14th International Society of Scientometrics and Informetrics Conference, 2013)
Since the telescope was invented in the early 17th century, astronomers have relied on increasingly complex and expensive instruments to further their studies of the Universe. The next generation of telescopes, with apertures of approximately 30-m, will cost more than $1B to construct. The main product of modern observatories are the publications in refereed journals based on data obtained using their telescope(s).

The observation of highly ordered domains in membranes with cholesterol - Armstrong, Clare L.; Marquardt, Drew; Dies, Hannah; Kučerka, Norbert; Yamani, Zahra; Harroun, Thad A.; Katsaras, John; Shi, An-Chang; Rheinstädter, Maikel C. (PLoS ONE, 2013)
Rafts, or functional domains, are transient nano- or mesoscopic structures in the exoplasmic leaflet of the plasma membrane, and are thought to be essential for many cellular processes. Using neutron diffraction and computer modelling, we present evidence for the existence of highly ordered lipid domains in the cholesterol-rich (32.5 mol%) liquid-ordered () phase of dipalmitoylphosphatidylcholine membranes. The liquid ordered phase in one-component lipid membranes has previously been thought to be a homogeneous phase. The presence of highly ordered lipid domains embedded in a disordered lipid matrix implies non-uniform distribution of cholesterol between the two phases. The experimental results are in excellent agreement with recent computer simulations of DPPC/cholesterol complexes [Meinhardt, Vink and Schmid (2013). Proc Natl Acad Sci USA 110(12): 4476–4481], which reported the existence of nanometer size domains in a liquid disordered lipid environment.

The JCMT Gould Belt Survey : SCUBA-2 observations of radiative feedback in NGC 1333 - Hatchell, J.; Wilson, T.; Drabek, E.; Curtis, E.; Richer, J.; Nutter, D.; Di Francesco, J.; Ward-Thompson, D. (Monthly Notices of the Royal Astronomical Society: Letters, 2013)
We present observations of NGC 1333 from SCUBA-2 on the James Clerk Maxwell Telescope (JCMT), observed as a JCMT Gould Belt Survey pilot project during the shared risk campaign when the first of four arrays was installed at each of 450 and 850 μm. Temperature maps are derived from 450 and 850 μm ratios under the assumption of constant dust opacity spectral index β = 1.8. Temperatures indicate that the dust in the northern (IRAS 6/8) region of NGC 1333 is hot, 20–40 K, due to heating by the B star SVS3, other young stars in the IR/optically visible cluster and embedded protostars. Other luminous protostars are also identified by temperature rises at the 17 arcsec resolution of the ratio maps (0.02 pc assuming a distance of 250 pc for Perseus). The extensive heating raises the possibility that the radiative feedback may lead to increased masses for the next generation of stars.
Keywords: stars: formation; dust; extinction; submillimetre: ISM; stars: protostars

The graphene phonon dispersion with C¹² and C¹³ isotopes - Whiteway, Eric; Bernard, Simon; Yu, Victor; Austing, D. Guy; Hilke, Michael (AIP Conference Proceedings, 2013)
Using very uniform large scale chemical vapor deposition grown graphene transferred onto silicon, we were able to identify 15 distinct Raman lines associated with graphene monolayers. This was possible thanks to a combination of different carbon isotopes and different Raman laser energies and extensive averaging without increasing the laser power. This allowed us to obtain a detailed experimental phonon dispersion relation for many points in the Brillouin zone. We further identified a D+D' peak corresponding to a double phonon process involving both an inter- and intra-valley phonon. In order to both eliminate substrate effects and to probe large areas, we undertook to study Raman scattering for large scale chemical vapor deposition (CVD) grown graphene using two different isotopes (C12 and C13) so that we can effectively exclude and subtract the substrate contributions, since a heavier mass downshifts only the vibrational properties, while keeping all other properties the same.

Abstract A248: integrated therapeutic antibody development at the National Research Council of Canada - Jaramillo, M. L.; Marcil, A.; Durocher, Y.; Gilbert, R.; Mullick, A.; Kelly, J.; O'connor-mccourt, M.; Massie, B. (Molecular Cancer Therapeutics, 2013)
Advances in genomics and antibody engineering have enabled the development of an innovative class of targeted therapies, namely therapeutic antibodies, for the treatment of diseases with significant unmet medical needs such as cancer. Therapeutic antibodies represent one of the largest and fastest growing classes of medications. The NRC has built a chain of cutting edge technology platforms needed to discover, engineer and produce therapeutic monoclonal antibodies with the goal of partnering with industrial and academic centers to advance research and development of this important class of therapeutics. Target Identification- To establish and validate the technology platforms, tumor targets for candidate therapeutic antibody production were identified using a combination of proteomics, transcriptomics and bioinformatic approaches. Out of these lists, approximately 40 tumor targets were selected (known therapeutic antibody targets were excluded), and over 3,000 antibodies of mouse and camelid origin were then generated against these targets. Antibody generation- Once identified, the recombinant target protein of interest was produced using the NRC's high efficiency cell expression platforms in CHO or HEK293 cells and purified protein was used for immunization or panning. For targets which were difficult to express or purify, the capabilities for direct immunization with plasmid DNA constructs were utilized. Clone selection was carried out by ELISA and typically 50 antibodies/target were identified for further characterization. Antibody characterization and validation- The affinities of the antibodies were determined by SPR biosensor analysis. Reverse phase protein arrays and Western blot analysis on protein mixes and cell line extracts allowed the characterization of the specificity of the antibodies. SPR-based epitope binning was carried out in order to characterize the diversity of the antibody collections and to enable the selection of representative antibodies from each epitope bin for further analysis. Select antibodies were assessed in appropriate cell-based assays for prioritization based on function. Therapeutic antibody Optimization, Bioprocessing and Biomanufacturing- Therapeutic antibodies selected for development can be further optimized using antibody engineering technologies to humanize them and/or modify their glycosylation patterns to improve their effector function, pharmacokinetics, solubility and stability as well as reduce their immunogenicity. The NRC platform for large scale protein production has the capacity to manufacture up to 500 g of commercial grade antibody using serum free, low endotoxin media in a cGMP certified CHO cell line which is ready for transfer to CMOs or other industrial partners.

The fundamentals and fun of biocatalysis - Lau, Peter C. K.; Grosse, Stephan (Marine Enzymes for Biocatalysis, 2013)

Final A&T stages of the Gemini Planet Finder - Hartung, Markus; Macintosh, Bruce; Poyneer, Lisa; Savransky, Dmitry; Gavel, Don; Palmer, Dave; Thomas, Sandrine; Dillon, Daren; Chilcote, Jeffrey; Ingraham, Patrick; Sadakuni, Naru; Wallace, Kent; et al. (Adaptive Optics for Extremely Large Telescopes (Third AO4ELT Conference), 2013)
The Gemini Planet Imager (GPI) is currently in its final Acceptance & Testing stages. GPI is an XAO system based on a tweeter & woofer architecture (43 & 9 actuators respectively across the pupil), with the tweeter being a Boston Michromachines 64² MEMS device. The XAO AO system is tightly integrated with a Lyot apodizing coronagraph. Acceptance testing started in February 2013 at the University of California, Santa Cruz. A conclusive acceptance review was held in July 2013 and the instrument was found ready for shipment to the Gemini South telescope on Cerro Pachon, Chile. Commissioning at the telescope will take place by the end of 2013, matching the summer window of the southern hemisphere. According to current estimates the 3 year planet finding campaign (890 allocated hours) might discover, image, and spectroscopically analyze 20 to 40 new exo-planets. Final acceptance testing of the integrated instrument can always bring up surprises when using cold chamber and flexure rig installations. The latest developments are reported. Also, we will give an overview of GPI's lab performance, the interplay between subsystems such as the calibration unit (CAL) with the AO bench. We report on-going optimizations on the AO controller loop to filter vibrations and last but not least achieved contrast performance applying speckle nulling. Furthermore, we will give an outlook of possible but challenging future upgrades as the implementation of a predictive controller or exchanging the conventional 48x48 SH WFS with a pyramid. With the ELT era arising, GPI will proof as a versatile and path-finding testbed for AO technologies on the next generation of ground-based telescopes.

Evaluation of astrometry errors due to the optical surface distortions in adaptive optics systems and science instruments - Ellerbroek, Brent; Herriot, Glen; Suzuki, Ryuji; Schoeck, Matthias (Third AO4ELT Conference - Adaptive Optics for Extremely Large Telescopes, 2013)
The objectives for high precision astrometry on ELTs will be challenging, with requirements in the range from 10 to 50 micro-arc-seconds for some instruments and science cases. Reducing and correctly calibrating the systematic and quasi-static errors introduced by optical surface distortions will be an important part of meeting these goals. In a recently submitted paper, we described an analytical Fourier domain model for evaluating these effects as the sum of three terms: (i) under-sampling errors, due to measuring the effects of static surface distortions using a finite number of discrete reference sources; (ii) unknown beam wander across the static surface distortions due to line-of-sight jitter or boresighting errors, and (iii) quasi-static errors due to slowly varying surface distortions. In this paper, we apply these methods to evaluating this term in the astrometry error budgets for the TMT Infrared Imaging Spectrograph (IRIS) and the facility AO system, NFIRAOS. The inputs to this exercise include the original top-down allocations for this error term, the original optical surface specifications for IRIS and NFIRAOS as derived earlier on the basis of wavefront error requirements, our assessment of the feasible density and positioning accuracy for an array of calibration sources, and the expected beam wander due to tip/tilt jitter and bore-sighting errors between NFIRAOS and IRIS. The astrometry error computed for these initial parameters was considerably larger than the top-down allocation due to the contributions from the NFIRAOS double-pane entrance window, which is close to the system's input focal plane. The error can be reduced to fall within the allocation by defining tighter, but still feasible, specifications for these elements. We also evaluated the astrometry errors due to quasi-static drift of the figures of the NFIRAOS deformable mirrors, and determined that they are acceptable for RMS wavefront distortions of up to about 30 nm RMS.

CLEO®/Europe - IQEC 2013 looking inside the recollision process - Shafir, Dror; Soifer, Hadas; Bruner, Barry D.; Dagan, Michal; Mairesse, Yann; Vozzi, Caterina; Stagira, Salvatore; Patchkovskii, Serguei; Ivanov, Misha Yu.; Smirnova, Olga; Dudovich, Nirit (2013 Conference on Lasers and Electro-Optics Europe and International Quantum Electronics Conference, 2013)
Probing the ionization times and the recollision times by adding a weak perturbation in simple atomic systems was discussed. The results deviated from the simple classical model were found to be in agreement with the quantum path analysis. The multiple channel ionization and the differences between two ionization channels were probed in aligned CO2 molecules.
Keywords: Ionization; Tunneling; Harmonic analysis; Radiative recombination

A new perspective on the development of cholesterol-lowering products - V.G., Sandhya; Wang, Yanwen (Using Old Solutions to New Problems: Natural Drug Discovery in the 21st Century, 2013)
Cardiovascular disease (CVD) is the principal cause of death worldwide, representing nearly 30% of the annual global mortality and 10% of global health burden. The current status of CVD is now on international scale; which can be considered as the commonest chronic illness in both developed and developing countries, causing the most deaths and the greatest impact on morbidity. In 2006, CVD was the leading cause of death for Canadians, representing 30% of all deaths. A total number of 1.3 million Canadians are diagnosed having heart disease accounting for 5% among those above 12 years and 23% at 75 years and older. The increased rate of obesity and diabetes combined with further aging of the population will likely lead to an increase in the number of people with CVD in the future. This will compromise the health of Canadians, put a strain on the health care system, and have a significant economic impact on Canada. Similarly, over the past five decades the prevalence of CVD has steadily increased in economically developing countries. These countries will account for 76% of an estimated 25 million death due to CVD in 2020. On an international basis, by 2020 CVD will reach nearly epidemic proportions and become the cause of more deaths, disability and economic loss than any others group of diseases. The number of fatalities by CVD projected to increase to over 20 million a year by 2020 and over 24 million a year by 2030. Apparently, understanding the aetiology of CVD and accordingly develop preventive and therapeutic approaches to address this health threat continues to be critically important in the next decades although significant achievements have been made in the past decades.

UV or PAA for wastewater disinfection: a comparison of the impact on virulence genes - Biswal, Basanta kumar; Gehr, Ronald; Khairallah, Ramzi; Bibi, Kareem; Mazza, Alberto; Masson, Luke; Frigon, Dominic (Proceedings of the Water Environment Federation, 2013)
Ultraviolet (UV) and peracetic acid (PAA) disinfection have been used in municipal wastewater treatment plants (WWTPs) for their biocidal effect on microorganisms. The current study used PCR-Bioplex and DNA microarray genotyping techniques to investigate the impact of UV and PAA on the change in frequency of virulence genes in E. coli isolates and on the prevalence of uropathogenic E. coli (UPEC) isolates in wastewater effluents. Effluents from four WWTPs (activated sludge [AS], biofiltration [BF] and physicochemical [PC1 and PC2]) located in Québec, Canada, were sampled before disinfection and exposed to UV or PAA doses in the lab to reach a target count of approximately 200 CFU/100 mL. To achieve this, the required UV fluences ranged between 7 – 30 mJ/cm2, depending on the plant, while the PAA dose varied between 0.9 – 2.0 mg/L. E. coli isolates totaling 1,766 were extracted from the samples pre- and post- disinfection, then screened by PCR/Bioplex to detect those likely to be UPECs, using three virulence genes (hlyA, papC and cnf1). The UPEC pathotypes of the positively screened isolates were confirmed by microarrays. The proportion of UPEC isolates decreased in all samples after disinfection, with that due to UV varying between 22% – 80%, and the reduction due to PAA ranging between 11% – 100%. The average reductions by UV (55%) and PAA (52%) were statistically significant (P<0.05). Gene frequency analysis revealed that the decline in the population of UPEC pathotypes by UV or PAA was not linked to specific virulence factors as most virulence genes were lost, suggesting that entire pathogenicity islands (PAIs), carrying clusters of virulence genes, were lost through disinfection. Thus, this study showed that both UV and PAA disinfection appear to significantly reduce the proportions of UPECs in the surviving E. coli populations in wastewater effluents.

Optimal routing strategies for autonomous underwater vehicles in time-varying environment - Eichhorn, Mike (Robotics and Autonomous Systems, 2013)
This paper presents a mission system and the therein implemented algorithms for path planning in a time-varying environment based on graph methods. The basic task of the introduced path planning algorithms is to find a time-optimal path from a defined start position to a goal position with consideration of the time-varying ocean current for an autonomous underwater vehicle (AUV). Building on this, additional practice-oriented considerations in planning are discussed in this paper. Such points are the discussion of possible methods to accelerate the algorithms and the determination of the optimal departure time. The solutions and algorithms presented in this paper are focused on path planning requirements for the AUV “SLOCUM Glider”. These algorithms are equally applicable to other AUVs or aerial mobile autonomous systems.
Keywords: path planning; geometrical graph; graph methods; time-varying environment; AUV; AUV “SLOCUM Glider”; autonomous systems

PO-0875: Patient specific scatter distributions in CBCT imaging calculated by Monte Carlo simulations - Thing, R.S.; Bernchou, U.; Mainegra-Hing, E.; Brink, C. (Radiotherapy and Oncology, 2013)
This paper proposes a hybrid software-hardware high-resolution projection system for 3D imaging based on fringe projection. The proposed solution combines the advantages of a digital projection with those of an analogue one. It is programmable and allows a high projection rate by avoiding mechanical displacements in the projection system. Moreover, it does not suffer from the limitations of digital systems such as the presence of inter-pixel gaps and limited resolution. The proposed projection system is relatively inexpensive to build since it is composed of a simple arrangement off-the-shelf components. The system is a combination of a low-resolution digital device such as a DMD, LCoS or LCD, some optical components and software to generate the fringe patterns. A prototype of a 3D scanner based on the proposed projection system is used to asses the fitness of the proposed technology.

Global framework for the assessment, development and demonstration of structural health and load monitoring systems - Rocha, Bruno; Yanishevsky, M.; Beltempo, Christopher Andre; Rutledge, Robert; Bellinger, Nicholas C.; Martinez, Marcias J. (CASI Conference Proceedings, 2013)
Properly deployed Structural Health Monitoring (SHM) has the potential to benefit the design, operation and maintenance of aircraft. For current aircraft, SHM could help extend operational lives while reducing operational (and maintenance) costs and increasing availability and operational safety. In addition, the implementation of SHM during the design stage of new aircraft could result in weight reduction through optimized design and the incorporation of active safety measures. However, a significant level of development, testing and demonstration is still required for SHM systems to attain the required maturity for deployment on ground and flight tests, and operational aircraft. With this intent, the National Research Council of Canada (NRC) has created a global framework, complete with a set of structural platforms facilitating an accurate assessment, development and demonstration of SHM systems. These platforms, with increasing levels of structural complexity, can accommodate SHM systems at different Technology Readiness Levels (TRL). The first level of structural complexity presents a simple 2 m long aluminium beam, with solid, rectangular cross section, the behaviour of which is well characterized through analytical and numerical methods. The second platform presents a slightly increased structural complexity, consisting of a typical representative 2 m long aircraft wing skin with riveted z-stringers, containing two different aluminium alloys. The third level of complexity presents a hybrid material aircraft wing box representative structure, with internal aluminium structures and carbon fibre reinforced epoxy composite skins. The final platforms consist of a full scale CF188 aircraft wing and a Bell 407 helicopter tail boom, representative of the current aerospace structures to trial sensors and measurement systems. In all of these platforms, representative load conditions applied during full scale tests or observed during flight operations can be applied through the use of several hydraulic actuators and actuation configurations. These load conditions range from static and quasi-static bending, torsion and coupled load conditions, to low frequency cyclic loading (either constant amplitude or operational spectra) and higher frequency vibration associated with buffet and flutter. Beyond the assessment, development and demonstration of load monitoring techniques and sensor systems, these platforms also offer the opportunity for the development and assessment of SHM techniques and systems capabilities to detect and monitor damage growth. In order to assess the TRL of the different SHM systems, replaceable components are introduced, either in a pristine condition, or with existing or artificially introduced representative damage, which can be grown during the application of the testing loads. Furthermore, these test platforms are being prepared to introduce representative flight operation environmental conditions, such as temperature and humidity.

Optical image sensors and their application in radon detection - Griffin, Ryan H.; Tarr, N. Garry; Cheben, Pavel; Schmid, Jens; Boudoux, Caroline; Chen, Lawrence R.; Delâge, André; Janz, Siegfried; Kashyap, Raman; Lockwood, David J.; Loock, Hans-peter; Mi, Zetian (Photonics North 2013, 2013)
This paper reports on the development and testing of a direct reading radon detector assembled from consumer electronics at very low cost. An electrostatic concentrator constructed by metalizing a plastic funnel is used to focus charged radon progeny onto the exposed surface of an optical image sensor from a webcam. Alpha particles emitted by the collected progeny strike the image sensor, generating sufficient charge to completely saturate one or more pixels The high voltage required by the concentrator is generated using a simple Cockcroft-Walton charge pump. A personal computer is used to analyze the webcam data. Alpha particles were counted at a rate of 5.2 counts/ hour at a radon concentration of 159 Bq/ m3.

Transferring markup tags in statistical machine translation: a two-stream approach - Joanis, Eric; Stewart, Darlene; Larkin, Samuel; Kuhn, Roland (Proceedings of the 2nd Workshop on Post-editing Technology and Practice (WPTP-2), 2013)
Translation agencies are introducing sta- tistical machine translation (SMT) into the work flow of human translators. Typ- ically, SMT produces a first-draft transla- tion, which is then post-edited by a per- son. SMT has met much resistance from translators, partly because of professional conservatism, but partly because the SMT community has often neglected some practical aspects of translation. Our paper discusses one of these: transferring formatting tags such as bold or italic from the source to the target document with a low error rate, thus freeing the post-editor from having to reformat SMT-generated text. In our “two-stream” approach, tags are stripped from the input to the decoder, then reinserted into the resulting target-language text. Tag trans- fer has been tackled by other SMT teams, but only a few have published descrip- tions of their work. This paper contrib- utes to understanding tag transfer by ex- plaining our approach in detail.

Translating the genomics revolution: the need for an international gene therapy consortium for monogenic diseases - Tremblay, Jacques p; Xiao, Xiao; Aartsma-rus, Annemieke; Barbas, Carlos; Blau, Helen m; Bogdanove, Adam j; Boycott, Kym; Braun, Serge; Breakefield, Xandra o; Bueren, Juan a; Buschmann, Michael; Byrne, Barry j; et al. (Molecular Therapy, 2013)

T4 report: a roadmap for hazard monitoring and risk assessment of marine biotoxins on the basis of chemical and biological test systems - Daneshian, Mardas; Botana, Luis M.; Bottein, Marie-Yasmine Dechraoui; Buckland, Gemma; Campàs, Mònica; Dennison, Ngaire; Dickey, Robert W.; Diogène, Jorge; Fessard, Valérie; Hartung, Thomas; Humpage, Andrew; Leist, Marcel; et al. (Altex, 2013)
Aquatic food accounts for over 40% of global animal food products, and the potential contamination with toxins of algal origin - marine biotoxins - poses a health threat for consumers. The gold standards to assess toxins in aquatic food have traditionally been in vivo methods, i.e., the mouse as well as the rat bioassay. Besides ethical concerns, there is also a need for more reliable test methods because of low inter-species comparability, high intra-species variability, the high number of false positive and negative results as well as questionable extrapolation of quantitative risk to humans. For this reason, a transatlantic group of experts in the field of marine biotoxins was convened from academia and regulatory safety authorities to discuss future approaches to marine biotoxin testing. In this report they provide a background on the toxin classes, on their chemical characterization, the epidemiology, on risk assessment and management, as well as on their assumed mode of action. Most importantly, physiological functional assays such as in vitro bioassays and also analytical techniques, e.g., liquid chromatography coupled mass spectrometry (LC-MS), as substitutes for the rodent bioassay are reviewed. This forms the basis for recommendations on methodologies for hazard monitoring and risk assessment, establishment of causality of intoxications in human cases, a roadmap for research and development of human-relevant functional assays, as well as new approaches for a consumer directed safety concept.
Keywords: marine biotoxins; risk assessment; consumer protection; regulatory toxicology

The distance to NGC 1316 (Fornax A): yet another curious case - Cantiello, M.; Grado, A.; Blakeslee, J. P.; Raimondo, G.; Di Rico, G.; Limatola, L.; Brocato, E.; Della Valle, M.; Gilmozzi, R. (Astronomy & Astrophysics, 2013)
AIMS: The distance of NGC 1316, the brightest galaxy in the Fornax cluster, provides an interesting test for the cosmological distance scale. First, because Fornax is the second largest cluster of galaxies within ≲25 Mpc after Virgo and, in contrast to Virgo, has a small line-of-sight depth; and second, because NGC 1316 is the single galaxy with the largest number of detected Type Ia supernovae (SNe Ia), giving the opportunity to test the consistency of SNe Ia distances both internally and against other distance indicators. METHODS: We measure surface brightness fluctuations (SBF) in NGC 1316 from ground- and space-based imaging data. The sample provides a homogeneous set of measurements over a wide wavelength interval. The SBF magnitudes, coupled with empirical and theoretical absolute SBF calibrations, are used to estimate the distance to the galaxy. We also present the first B-band SBF measurements of NGC 1316 and use them together with the optical and near-IR SBF data to analyze the properties of field stars in the galaxy. RESULTS: We obtain mag, or d = 20.8 ± 0.5(stat.) ± 1.5(sys.) Mpc. When placed in a consistent Cepheid distance scale, our result agrees with the distances from other indicators. On the other hand, our distance is ~17% larger than the most recent estimate based on SNe Ia. Possible explanations for this disagreement are the uncertain level of internal extinction, and/or calibration issues. Concerning the stellar population analysis, we confirm the results from other spectro-photometric indicators: the field stars in NGC 1316 are dominated by a component with roughly solar metallicity and intermediate age. A non-negligible mismatch exists between B-band SBF models and data. We confirm that such behavior can be accounted for by an enhanced percentage of hot horizontal branch stars. CONCLUSIONS: Our study of the SBF distance to NGC 1316, and the comparison with distances from other indicators, raises some concern about the homogeneity between the calibrations of different indicators. If not properly placed in the same reference scale, significant differences can occur, with dramatic impact on the cosmological distance ladder. Our results on the stellar populations properties show that SBF data over a broad wavelength interval are an efficient means of studying the properties of unresolved systems in peculiar cases like NGC 1316.
Keywords: Elliptical galaxies; Lenticular galaxies; Galaxy distances; Redshifts; Cluster galaxies; Galaxy NGC 1316; Galaxy photometry; Stellar content; Peculiar galaxies

The alleviation of wake vortex encounter loads, a study of flight research data - Brown, Anthony P. (Transactions of Japanese Society for Medical and Biological Engineering, 2013)
Wake vortex encounters, occurring in air transport operations, involve substantial loads, which can result in aggravated flight-path upsets. In order to explore flight control system design for alleviation, the alleviatory effects of conventional flight control surface deflections, upon wake vortex encounter loads has been examined. For this, data was gathered during NRC T33 wake turbulence flight research, of Heavy and Super Category jet transports engaged in enroute operations. Comparative data consists of stick-fixed wake vortex encounters and manually-applied alleviatory control inputs to conventional flight control surfaces. For the alleviatory control-input case, the inputs are experience-based, fully-learned, in other words categorised as instinctive. As such, they were of a high frequency-band, for manual control inputs. Thus, they represent a close-to-limit ability to alleviate wake vortex encounter loads, for the T33 with manual control inputs. The reduction in loads between the two cases, stick-fixed and stick-alleviatory was of the order of 50-60%. Given the greater bandwidth of digital flight control systems, it is reasonable to speculate that a wake vortex loads alleviation of significantly greater than 50% could be possible with a digital flight control system, based upon the appropriate flight control laws.

Texture based segmentation method to detect atherosclerotic plaque from optical tomography images - Prakash, Ammu; Hewko, Mark; Sowa, Michael; Sherif, Sherif (Advanced microscopy techniques III, 2013)
Optical coherence tomography (OCT) imaging has been widely employed in assessing cardiovascular disease. Atherosclerosis is one of the major cause cardio vascular diseases. However visual detection of atherosclerotic plaque from OCT images is often limited and further complicated by high frame rates. We developed a texture based segmentation method to automatically detect plaque and non plaque regions from OCT images. To verify our results we compared them to photographs of the vascular tissue with atherosclerotic plaque that we used to generate the OCT images. Our results show a close match with photographs of vascular tissue with atherosclerotic plaque. Our texture based segmentation method for plaque detection could be potentially used in clinical cardiovascular OCT imaging for plaque detection.
Keywords: Atherosclerosis; Image processing; Image texture; Optical coherence tomography; Plaque

Structure of the benzene dimer - governed by dynamics - Schnell, Melanie; Erlekam, Undine; Bunker, P. R.; von Helden, Gert; Grabow, Jens-Uwe; Meijer, Gerard; van der Avoird, Ad (Angewandte Chemie International Edition, 2013)
The benzene dimer, an important prototype for studying noncovalent interactions, exhibits characteristic splitting patterns in its rotational spectrum, which for a long time were not understood. A new theoretical model reveals their origin: a concerted internal motion involving sixfold hindered rotation tunneling of the molecule forming the stem of the T-shaped structure and tilt tunneling of the cap.
Keywords: Ab initio calculations; Internal rotation; Noncovalent interactions; Rotational spectroscopy; Tunneling

Single-domain antibodies and their utility - Baral, Toya Nath; MacKenzie, Roger; Ghahroudi, Mehdi Arbabi (Current Protocols in Immunology, 2013)
Engineered monoclonal antibody fragments have gained market attention due to their versatility and tailor-made potential and are now considered to be an important part of future immunobiotherapeutics. Single-domain antibodies (sdAbs), also known as nanobodies, are derived from VHHs [variable domains (V) of heavy-chain-only antibodies (HCAb)] of camelid heavy-chain antibodies. These nature-made sdAbs are well suited for various applications due to their favorable characteristics such as small size, ease of genetic manipulation, high affinity and solubility, overall stability, resistance to harsh conditions (e.g., low pH, high temperature), and low immunogenicity. Most importantly, sdAbs have the feature of penetrating into cavities and recognizing hidden epitopes normally inaccessible to conventional antibodies, mainly due to their protruding CDR3/H3 loops. In this unit, we will present and discuss comprehensive and step-by-step protocols routinely practiced in our laboratory for isolating sdAbs from immunized llamas (or other members of the Camelidae family) against target antigens using phage-display technology. Expression, purification, and characterization of the isolated sdAbs will then be described, followed by presentation of several examples of applications of sdAbs previously characterized in our laboratory and elsewhere.
Keywords: Single-domain antibody; Heavy-chain antibodies; VHH; Antibody fragment; Dimeric VHH; Pentabodies; Multivalency

Simulation studies of the Cl⁻ + CH₃I SN2 nucleophilic substitution reaction: Comparison with ion imaging experiments - Zhang, Jiaxu; Lourderaj, Upakarasamy; Sun, Rui; Mikosch, Jochen; Wester, Roland; Hase, William L. (The Journal of Chemical Physics, 2013)
In the previous work of Mikosch Science 319, 183 (2008)10.1126/science. 1150238, ion imaging experiments were used to study the Cl⁻ CH₃I → ClCH₃ I⁻ reaction at collision energies Erel of 0.39, 0.76, 1.07, and 1.9 eV. For the work reported here MP2(fc)ECPd direct dynamics simulations were performed to obtain an atomistic understanding of the experiments. There is good agreement with the experimental product energy and scattering angle distributions for the highest three Erel, and at these energies 80 or more of the reaction is direct, primarily occurring by a rebound mechanism with backward scattering. At 0.76 eV there is a small indirect component, with isotropic scattering, involving formation of the pre- and post-reaction complexes. All of the reaction is direct at 1.07 eV. Increasing Erel to 1.9 eV opens up a new indirect pathway, the roundabout mechanism. The product energy is primarily partitioned into relative translation for the direct reactions, but to CH₃Cl internal energy for the indirect reactions. The roundabout mechanism transfers substantial energy to CH₃3Cl rotation. At E rel 0.39 eV both the experimental product energy partitioning and scattering are statistical, suggesting the reaction is primarily indirect with formation of the pre- and post-reaction complexes. However, neither MP2 nor BhandHECPd simulations agree with experiment and, instead, give reaction dominated by direct processes as found for the higher collision energies. Decreasing the simulation Erel to 0.20 eV results in product energy partitioning and scattering which agree with the 0.39 eV experiment. The sharp transition from a dominant direct to indirect reaction as Erel is lowered from 0.39 to 0.20 eV is striking. The lack of agreement between the simulations and experiment for Erel 0.39 eV may result from a distribution of collision energies in the experiment andor a shortcoming in both the MP2 and BhandH simulations. Increasing the reactant rotational temperature from 75 to 300 K for the 1.9 eV collisions, results in more rotational energy in the CH₃Cl product and a larger fraction of roundabout trajectories. Even though a ClCH₃-I⁻ post-reaction complex is not formed and the mechanistic dynamics are not statistical, the roundabout mechanism gives product energy partitioning in approximate agreement with phase space theory.
Keywords: Reaction mechanisms; Collusion induced chemical reactions; Density functional theory; Ion molecule reactions; Energy transfer

Simplified non-linear FE model to predict staged capacity deterioration of RC columns subjected to combined ultimate or seismic and reinforcement corrosion loads - Mohammed, Amina; Almansour, Husham (Annual Conference of the Canadian Society for Civil Engineering 2013: Know-How - Savoir-Faire, 2013)
The quasi-static and the low frequency cyclic loading-to-failure tests have shown that the stiffness degradation and strength of RC columns are reduced in a staged pattern. Although several studies have demonstrated this strength and stiffness degradation using complicated high-level 2D and 3D modeling approaches, a simplified numerical approach is required. Simplified non-linear finite element model developed by the authors is used in this paper to capture the staged damage and collapse of RC columns subjected to extreme loads. The model performs inelastic sectional and element analysis phases considering the instantaneous and successive changes of the sectional and element properties throughout the progress of the loading steps and the critical stages of corrosion-induced damages. The model considers all possible state of strain distributions on a concrete beam-column, and the nonlinear instantaneous sectional properties and the internal forces are calculated ensuring the equilibrium of all the internal and external forces in the section level. It is found that the proposed simplified nonlinear finite element model is numerically stable in all cases of strain distributions, both in static and dynamic analysis. The model shows that the load displacement curve of the columns subjected to quasi-static loading or the envelop of the load-displacement hysteretic relationship can be found using quasi-static analysis. The model can predict the nonlinear behavior of non-corroded and corroded specimens with high accuracy. Further research is required to accurately define the critical stages of damages incorporating field and experimental data of damaged RC columns and higher level non-linear finite element techniques.

Short/Small crack model development for aircraft structural life assessment - Liao, Min; Renaud, Guillaume; Bombardier, Yan (13th International Conference on Fracture 2013, ICF 2013, 2013)
This paper presents the testing and modeling results from an NRC project on short/small1 crack model development for aircraft structures. Fatigue tests were conducted for 7075-T73 hand forging aluminium material using precracked compact tension (C(T)) and naturally cracked single edge-notch tension (SENT) coupons, under various stress ratios. The adjusted compliance ratio (ACR) method was used for the C(T) coupon tests aiming to quantify remote closure due to plasticity and forging-induced residual stresses. For the SENT coupons, three-dimensional StressCheck finite element (FE) models were developed to accurately calculate the stress intensity factors of surface and corner cracks. Both C(T) and SENT test data were combined to develop short-long fatigue crack growth rate models. These models were then used in crack growth life analyses for coupon and component cases, taken from transport aircraft under spectrum loadings. It was shown that the newly developed models resulted in more accurate fatigue life estimations.

Shaping polarization of attosecond pulses via laser control of electron and hole dynamics - Morales, F.; Barth, I.; Serbinenko, V.; Patchkovskii, S.; Smirnova, O. (2013 Conference on Lasers & Electro-Optics Europe & International Quantum Electronics Conference CLEO EUROPE/IQEC, 2013)
We present [1] a way to control and shape the polarization of attosecond pulses generated by HHG by using the combination of the fundamental radiation and its second harmonic, both linearly polarized, in perpendicular geometry. By extending the multi-electron analysis done in the C02 molecule in previous works [2] to treat the two-color laser fields, we explore the rich possibilities that this control mechanism offers.

Shaping polarization of attosecond pulses via laser control of electron and hole dynamics - Morales, F.; Barth, I.; Serbinenko, V.; Patchkovskii, S.; Smirnova, O. (2013 Conference on Lasers & Electro-Optics, International Quantum Electronics Conference, 2013)

Serum biomarkers of papillary thyroid cancer - Makki, Fawaz M.; Taylor, S. Mark; Shahnavaz, Ali; Leslie, Andrew; Gallant, Jeffrey; Douglas, Susan; Teh, Evelyn; Trites, Jonathan; Bullock, Martin; Inglis, Karen; Pinto, Devanand M.; Hart, Robert D. (Journal of Otolaryngology - Head and Neck Surgery, 2013)
OBJECTIVE: To identify serum biomarkers of papillary thyroid cancer. METHODS: Prospective analysis was performed of banked tumor and serum specimens from 99 patients with thyroid masses. Enzyme-linked immunosorbent assay (ELISA) was employed to measure levels of five serum proteins previously demonstrated to be up-regulated in papillary thyroid cancer (PTC): angiopoietin-1 (Ang-1), cytokeratin 19 (CK-19), tissue inhibitor of metalloproteinase-1 (TIMP-1), chitinase 3 like-1 (YKL-40), and galectin-3 (GAL-3). Serum levels were compared between patients with PTC and those with benign tumors. RESULTS: A total of 99 patients were enrolled in the study (27 men, 72 women), with a median age of 54 years. Forty-three patients had PTC and 58 cases were benign tumors. There were no statistically significant differences when comparing all five different biomarkers between PTC and other benign thyroid tumors. The p-values were 0.94, 0.48, 0.72, 0.48, and 0.90 for YKL-40, Gal-3, CK19, TIMP-1, and Ang-1, respectively. CONCLUSIONS: Serum levels of four of the five proteins were elevated in patients with thyroid masses relative to normal values. However, the difference between benign and PTC was not significant. Two of the markers (Gal-3 & TIMP-1) displayed a greater potential difference, which may warrant further investigation. This study suggests that other serum markers should be sought. This is the first study to investigate potential serum biomarkers based on over-expressed proteins in thyroid cancer versus benign pathology.
Keywords: Thyroid; Cancer; Papillary; Serum biomarkers

Sensespotting: never let your parallel data tie you to an old domain - Carpuat, Marine; Daume III, Hal; Henry, Katie; Irvine, Ann; Jagarlamudi, Jagadeesh; Rudinger, Rachel (ACL 2013 - 51st Annual Meeting of the Association for Computational Linguistics, Proceedings of the Conference, 2013)
Words often gain new senses in new domains. Being able to automatically identify, from a corpus of monolingual text, which word tokens are being used in a previously unseen sense has applications to machine translation and other tasks sensitive to lexical semantics. We define a task, SenseSpotting, in which we build systems to spot tokens that have new senses in new domain text. Instead of difficult and expensive annotation, we build a goldstandard by leveraging cheaply available parallel corpora, targeting our approach to the problem of domain adaptation for machine translation. Our system is able to achieve F-measures of as much as 80%, when applied to word types it has never seen before. Our approach is based on a large set of novel features that capture varied aspects of how words change when used in new domains.

Revising ASHRAE climatic data for design and standards - Part 1: Overview and data - Thevenard, Didier; Cornick, Steve (ASHRAE Transactions, 2013)
ASHRAE Research Project RP-1613 prepared an update of the climatic design conditions for the "Climatic Design Information" chapter of ASHRAE Handbook--Fundamentals and for ANSI/ASHRAE Standard 169, Weather Data for Building Design Standards. This update resulted in an increase of the number of stations to 6443 (a 16% increase compared to 2009) and the inclusion of precipitation data used in particular to determine climate zones in energy standard ANSI/ ASHRAE/IES Standard 90.1. A more recent period of record (1986-2010 for most stations) was used to incorporate changes in the climate. Compared to the previous edition, climatic design temperatures are generally slightly higher, cooling degree are slightly higher, and heating degree-days are lower, which is indicative of a general warming of the climate. In addition, RP-1613 prepared an update of the Weather Data Viewer, a stand-alone product used by engineers to access the full single- and joint-frequency distributions of all the climatic design parameters listed in ASHRAE Handbook--Fundamentals, as well as additional parameters, such as temperature bin data and wind roses. Part two of the paper, "Revising ASHRAE Climatic Data for Design and Standards--Part II: Clear-Sky Solar Radiation Model," provides a detailed description of the changes made to the clear-sky solar radiation model.

Review of Canadian flight deck and cabin smoke and fire incidents: 2001-2010 - Lebbin, Paul (SAE International Journal of Aerospace, 2013)
This paper presents a review of the flight deck and cabin fire and smoke incidents reported to the Canadian airworthiness authorities over a ten year span. The fire and smoke related diversions are categorized to identify areas where efforts could be increased to improve safety. The costs of diversions are estimated to identify areas where operators could reduce costs by seeking technologies to reduce the number of diversions without any impact on safety. Only twenty-eight investigation reports into fire and smoke incidents onboard aircraft have been published over the past three decades. These reports are not sufficient to identify areas where operators can reduce their operating costs. The Canadian airworthiness authorities received over 1,000 smoke and fire incidents from the years 2001 to 2010, of which, over 680 reported fire and smoke in the flight deck and cabin compartments for various makes and models of aircraft. Some of these flight deck and cabin incidents were related to in-flight entertainment or galley systems that were remedied while in-flight and did not require a diversion in most cases. The remaining incidents were found to be related to ingestion of oil, de-icing fluids and equipment and electrical failures that, in many cases, prompted the pilots to declare an emergency and divert. This paper categorizes the flight deck and cabin related fire and smoke incidents to suggest specific areas for airframers and operators to focus their efforts in reducing flight diversions that will not only reduce costs, but improve safety.

Residual stresses in welded stiffened steel plates—an experimental comparative study - Kenno, Sara Y.; Das, Sreekanta; Rogge, Ronald B.; Gharghouri, Michael A. (Materials Performance and Characterization, 2013)
This paper examines the residual stress distributions at selected depths in three stiffened 350WT steel plates representing typical stiffened steel plates used in modern ship construction. Residual stresses can develop from the welding process, and the magnitude of these stresses can be high enough to cause an early onset of yielding. Therefore, fatigue or other failures can also occur when welding-induced residual stresses are combined with service-load-induced stresses. In this study, the welding-induced residual stresses of these stiffened steel plate specimens were quantified at the near surface using the X-Ray diffraction method and at various depths using the neutron diffraction method. Transverse and longitudinal stress components for all three specimens were collected and analyzed. The residual stress profiles determined from both methods were found to be similar. However, some disagreement was found within the heat-affected zone of the weld bead. This paper discusses the residual stress distributions found in the three specimens and compares the two methods of measurement.
Keywords: Diffraction; Residual stresses; Stiffened steel plate; Welding-induced residual stresses

Relating centromeric topography in fixed human chromosomes to a-satellite DNA and CENP-B distribution - Khan, W. A.; Chisholm, R.; Tadayyon, S.; Subasinghe, A.; Norton, P.; Samarabandu, J.; Johnston, L. J.; Knoll, J. H.; Rogan, P. K. (Cytogenetic and Genome Research, 2013)
Despite extensive analyses on the centromere and its associated proteins, detailed studies of centromeric DNA structure have provided limited information about its topography in condensed chromatin. We have developed a method with correlative fluorescence light microscopy and atomic force microscopy that investigates the physical and structural organization of -satellite DNA sequences in the context of its associated protein, CENP-B, on human metaphase chromosome topography. Comparison of centromeric DNA and protein distribution patterns in fixed homologous chromosomes indicates that CENP-B and -satellite DNA are distributed distinctly from one another and relative to observed centromeric ridge topography. Our approach facilitates correlated studies of multiple chromatin components comprising higher-order structures of human metaphase chromosomes.
Keywords: Satellite DNA; Atomic force microscopy; CENP-B; Centromere topography; Human metaphase chromosomes; Immuno-FISH

Re-inventing multimode interference couplers using subwavelength gratings - Ortega-Monux, A.; Halir, R.; Maese-Novo, A.; Alonso-Ramos, C.; Zavargo-Peche, L.; Perez-Galacho, D.; Molina-Fernandez, I.; Wanguemert-Perez, J. G.; Cheben, P.; Schmid, J. H.; Lapointe, J.; Xu, D.; et al. (2013 Conference on Lasers & Electro-Optics Europe & International Quantum Electronics Conference CLEO EUROPE/IQEC, 2013)
Multimode-Interference (MMI) devices are fundamental building blocks in photonic integrated circuits, where they are used for power splitting and combining, optical switches and modulators, Mach-Zehnder interferometers and 90o hybrids for coherent optical receivers. MMIs are based on the self-image principle, by which the guided modes of the multimode region interfere to form replicas of the input field with specific amplitude and phase relations. These relations are known to depend on i) the core/cladding refractive indexes (n₁/n₂), ii) the core width (W) and length (L) of the multimode region and iii) the number, width and position of the access ports. In this work, we show that by using sub-wavelength structures within an MMI, the self-imaging properties can be significantly altered, leading to ultra-short or ultra-broadband devices.
Keywords: Bragg gratings; Talbot effect; Integrated optoelectronics; Light interference; Optical couplers; Refractive index

Re-inventing multimode interference couplers using subwavelength gratings - Ortega-Monux, A.; Halir, R.; Maese-Novo, A.; Alonso-Ramos, C.; Zavargo-Peche, L.; Perez-Galacho, D.; Molina-Fernandez, I.; Wanguemert-Perez, J. G.; Cheben, P.; Schmid, J. H.; Lapointe, J.; Xu, D.; et al. (Optics InfoBase Conference Papers, 2013)

Reflections on journal bearings performance with surface texturing - Dadouche, Azzedine; Conlon, Martin J. (5th World Tribology Congress, WTC 2013, 2013)

Rectification of piezoelectric dynamometer force signals during low frequency vibration assisted drilling - Sadek, A.; Meshreki, M.; Attia, M. H. (ASME 2013 International Mechanical Engineering Congress and Exposition Volume 2B: Advanced Manufacturing, 2013)
In vibration assisted drilling (VAD), a controlled harmonic motion is superimposed over the principal drilling feed motion in order to create an intermittent cutting state, which reduces cutting forces and temperatures, facilitates chip removal, and increases the possibility for dry machining. However, accurate force measurements during VAD operations has been a challenge especially in systems, where the force transducer is part of the vibrating mass mounted on the shaker head, due to the dynamic force errors. Conventional signal filtering and compensation techniques were found to be not applicable for attenuating undesirable VAD dynamic force components, which exist in the measured force signals at the same frequency of superimposed modulation. This research work presents a corrective dynamic model that rectifies the erroneous VAD tangential and axial force signals measured by a commercial piezoelectric dynamometer mounted on electro-magnetic shakers for the low frequency/high amplitude (LF/HA) regime. An experimental modal analysis in tangential and axial directions was conducted in order to define the transfer function of a multiple degrees of freedom VAD system mounted on a vibrating base (shaker). The rectified force is then obtained by plugging the relative motion between the dynamometer base and face measured during cutting into the system transfer function. The predicted rectified force components showed very high conformance with known impact and sinusoidal excitation forces used for validation. Moreover, the developed corrective model was capable of predicting some features in the VAD force signals that were not fully captured in the measured force signals during cutting.
Keywords: Drilling; Vibration; Signals; Dynamometers

Production of ceramic coatings on AA6061 aluminum alloy using plasma electrolytic oxidation - Dehnavi, Vahid; Luan, Ben Li; Liu, Xing Yang; Shoesmith, David W.; Rohani, Sohrab (Materials Science and Technology Conference and Exhibition 2013, MS and T 2013, 2013)
Plasma electrolytic oxidation (PEO) is a relatively novel surface finishing technique that converts the surface of light metals and alloys into oxide layers. For Al alloys, the coatings produced by PEO mainly consist of oxides with high hardness and therefore are more suitable for tribological applications than the substrate material. The PEO coatings can also effectively protect the base metal against corrosion. In this study ceramic coatings were deposited on 6061 Al alloy substrates using an alkaline electrolyte. The morphology, microstructure, compositions, and growth behavior of the coatings were analyzed using SEM, energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). The results suggest that the coating growth behavior is a function of the PEO process stages. This information can be used to better understand the PEO coating growth behavior and to improve the quality of the coatings for required applications.
Keywords: Aluminum alloy 6061; Ceramic coatings; Plasma electrolytic oxidation

Preparation for scaling studies of ice-crystal icing at the NRC Research Altitude Test Facility - Struk, Peter M.; Bencic, Timothy; Tsao, Jen-Ching; Fuleki, Dan; Knezevici, Daniel C. (5th AIAA Atmospheric and Space Environments Conference, 2013)
This paper describes preparation for ice-crystal icing scaling work utilizing the Cascade rig at the National Research Council (NRC) of Canada’s Research Altitude Test Facility (RATFac). Tests supporting this work and continuing the collaboration between NASA and NRC on ice-crystal icing took place between March 26 and April 11, 2012. The focus was on several aspects but emphasized characterization of the RATFac cloud including watercontent and test-section uniformity as well as particle-size measurements. Water content measurements utilized the Science Engineering Associates (SEA) Multi-Element probe while cloud uniformity measurements used light scattering from particles passing through a laser sheet. Finally, particle size-spectra measurements used two developmental shadowgraph systems. Details of these measurements as well as selected results are presented. An analysis algorithm is presented that interprets mixed-phase measurements from the SEA probe using calibrations from individual water and ice clouds. The analysis is applied to one mixedphase data set generated with a glaciated cloud combined with supplemental water. The test section temperature was below freezing to prevent the natural melting of the ice crystals. The analysis algorithm relies on the measurement of test-section humidity to account for cloud evaporation. Results of the cloud-uniformity measurements using scattered light suggest that the measured intensity is a good first-order measurement of concentration, independent of the water phase. Steeper intensity gradients across the test section are observed with increasing ice-water content. For particle-size measurements, both shadowgraphy methods provide high-quality images of the particles. These images will be processed to establish particle-size distributions and morphology characteristics. The results from this work will help guide future ice-crystal icing research including scaling studies.

Power spectra and auto correlation analysis of hyperfine-induced long period oscillations in the tunneling current of coupled quantum dots - Harack, B.; Leary, A.; Coish, W. A.; Hilke, M.; Yu, G.; Payette, C.; Gupta, J. A.; Austing, D. G. (The Physics of Semiconductors: Proceedings of the 31st International Conference on the Physics of Semiconductors (ICPS), 2013)
We outline power spectra and auto correlation analysis performed on temporal oscillations in the tunneling current of coupled vertical quantum dots. The current is monitored for ∼2325 s blocks as the magnetic field is stepped through a high bias feature displaying hysteresis and switching: hallmarks of the hyperfine interaction. Quasi-periodic oscillations of ∼2 pA amplitude and of ∼100 s period are observed in the current inside the hysteretic feature. Compared to the baseline current outside the hysteretic feature the power spectral density is enhanced by up to three orders of magnitude and the auto correlation displays clear long lived oscillations about zero.
Keywords: Quantum dots; Tunneling; Magnetic fields; Spectrum analysis; Magnetic hysteresis

Plant Acyl-CoA:Lysophosphatidylcholine Acyltransferases (LPCATs) have different specificities in their forward and reverse reactions - Lager, Ida; Lindberg Yilmaz, Jenny; Zhou, Xue-Rong; Jasieniecka, Katarzyna; Kazachkov, Michael; Wang, Peng; Zou, Jitao; Weselake, Randall; Smith, Mark A.; Bayon, Shen; Dyer, John M.; Shockey, Jay M.; et al. (Journal of Biological Chemistry, 2013)
Acyl-CoA:lysophosphatidylcholine acyltransferase (LPCAT) enzymes have central roles in acyl editing of phosphatidylcholine (PC). Plant LPCAT genes were expressed in yeast and characterized biochemically in microsomal preparations of the cells. Specificities for different acyl-CoAs were similar for seven LPCATs from five different species, including species accumulating hydroxylated acyl groups in their seed oil, with a preference for C18-unsaturated acyl-CoA and low activity with palmitoyl-CoA and ricinoleoyl (12-hydroxyoctadec-9-enoyl)-CoA. We showed that Arabidopsis LPCAT1 and LPCAT2 enzymes catalyzed the acylation and de-acylation of both sn positions of PC, with a preference for the sn-2 position. When acyl specificities of the Arabidopsis LPCATs were measured in the reverse reaction, sn-2-bound oleoyl, linoleoyl, and linolenoyl groups from PC were transferred to acyl-CoA to a similar extent. However, a ricinoleoyl group at the sn-2-position of PC was removed 4–6-fold faster than an oleoyl group in the reverse reaction, despite poor utilization in the forward reaction. The data presented, taken together with earlier published reports on in vivo lipid metabolism, support the hypothesis that plant LPCAT enzymes play an important role in regulating the acyl-CoA composition in plant cells by transferring polyunsaturated and hydroxy fatty acids produced on PC directly to the acyl-CoA pool for further metabolism or catabolism.

PLA melt crystallization and stereocomplex formation enhancement by means of nucleation and plasticization - Saeidlou, Sajjad; Huneault, Michel A.; Li, Hongbo; Park, Chul B. (Annual Technical Conference - ANTEC, Conference Proceedings, 2013)
Effect of the two crystallization enhancement strategies, i.e. nucleation and plasticization, which are commonly used to promote polylactide (PLA) homocrystallization was investigated on the stereocomplex formation between poly(L-lactic acid) (PLLA) and poly(D-lactic acid) (PDLA). The goal was to enhance the kinetics and yield of stereocomplex formation from the melt for future applications in PLA melt processing. Blends with 5% PDLA with nucleating agent and/or plasticizer were prepared via melt-blending and characterized by differential scanning calorimetry (DSC) technique. Results suggest that combination of nucleation and plasticization is very effective in simultaneous enhancement of stereocomplex formation and homocrystallization.

Photouncaging of ceramides promotes reorganization of liquid-ordered domains in supported lipid bilayers - Carter Ramirez, Daniel M.; Pitre, Spencer P.; Kim, Young Ah; Bittman, Robert; Johnston, Linda J. (Langmuir, 2013)
6-Bromo-7-hydroxycoumarin (Bhc)-caged ceramide (Cer) analogs were incorporated into supported lipid bilayers containing a mixture of coexisting liquid-ordered (L₀) and liquid-disordered (Ld) phases. The release of N-palmitoyl and N-butanoyl-d-erythro-sphingosine (C16- and C4-Cer) by the photolysis of caged Cers using long-wavelength UV light was studied using a combination of atomic force microscopy and fluorescence microscopy. This approach demonstrated the ability to generate Cer with spatial and temporal control, providing an alternative method to the enzymatic generation of Cer. The generation of C16-Cer from Bhc-C16-Cer disrupted the L₀ domains, with the incorporation of small fluid-phase regions and the disappearance of some smaller domains. Cer-rich gel-phase domains were not observed, in contrast to results reported by either direct Cer incorporation or enzymatic Cer generation. The photorelease of C4-Cer from Bhc-C4-Cer resulted in qualitatively similar changes in bilayer morphology, with the disappearance of some L₀ domains and no evidence of Cer-rich gel domains but with a smaller height difference between the ordered and disordered phases.

Pentavalent single-domain antibodies reduce Campylobacter jejuni motility and colonization in chickens - Riazi, Ali; Strong, Philippa C. R.; Coleman, Russell; Chen, Wangxue; Hirama, Tomoko; van Faassen, Henk; Henry, Matthew; Logan, Susan M.; Szymanski, Christine M.; MacKenzie, Roger; Ghahroudi, Mehdi Arbabi; Mantis, Nicholas J. (PLoS ONE, 2013)
Campylobacter jejuni is the leading cause of bacterial foodborne illness in the world, with symptoms ranging from acute diarrhea to severe neurological disorders. Contaminated poultry meat is a major source of C. jejuni infection, and therefore, strategies to reduce this organism in poultry, are expected to reduce the incidence of Campylobacter-associated diseases. We have investigated whether oral administration of C. jejuni-specific single-domain antibodies would reduce bacterial colonization levels in chickens. Llama single-domain antibodies specific for C. jejuni were isolated from a phage display library generated from the heavy chain IgG variable domain repertoire of a llama immunized with C. jejuni flagella. Two flagella-specific single-domain antibodies were pentamerized to yield high avidity antibodies capable of multivalent binding to the target antigen. When administered orally to C. jejuni-infected two-day old chicks, the pentabodies significantly reduced C. jejuni colonization in the ceca. In vitro, the motility of the bacteria was also reduced in the presence of the flagella-specific pentabodies, suggesting the mechanism of action is through either direct interference with flagellar motility or antibody-mediated aggregation. Fluorescent microscopy and Western blot analyses revealed specific binding of the anti-flagella pentabodies to the C. jejuni flagellin.

Particle size effects on ice crystal accretion - part II - Knezevici, Daniel C.; Fuleki, Dan; Currie, Thomas C.; Galeote, Brian; Chalmers, Jennifer; Macleod, James D. (5th AIAA Atmospheric and Space Environments Conference, 2013)
This paper describes ongoing research intended to simulate ice accretion in an inter-compressor duct bleed slot resulting from the ingestion of altitude ice crystals. The authors have previously shown that ice crystal particle size plays an important role in the ice crystal accretion phenomenon. It was also shown that ice crystal particle size affects the degree of natural melt that occurs for a given aerodynamic condition. The data presented herein decouples the effects of ice particle melt and particle size distribution to generate accretions with the same ratio of freestream liquid-to-total water fraction. The effects of wet bulb temperature and ice particle size on the natural melting of ice crystals are discussed. An ice preservation procedure is followed to allow tracings of the accretion to be taken along the test article. Ice crystal particle size distribution is characterized using a shadowgraphy imaging technique. Finally, the reduction in accretion rate relative to the theoretical maximum rate of surface accretion by ice crystal particles is discussed. The test article simulates a forward facing, inclined endwall bleed slot in a gas turbine compressor as a simplified two-dimensional representation. The geometry, having a surface inclined 20° to the incoming flow, proved to be susceptible to mixed phase ice crystal accretion. Particle size and particularly the large particle tail of the distribution had a significant impact on the magnitude of accretion under mixed phase test conditions for wet bulb temperatures above and below 0°C. The leading edge growth rates were found to be 1/4 to 1/9 of the theoretical growth rate suggesting that erosion, splashing, particle bounce and other loss mechanism rates are significant. The ice tracings were used to estimate an accretion mass for a hypothetical large bypass ratio gas turbine. It was found that approximately 4kg of ice could be generated should the inter-compressor duct be exposed to the conditions tested for 5 minutes.

Oxygen transport parameters in Nafion(R) 117 under controlled relative humidity - Novitski, D.; Xie, Z.; Holdcroft, S. (ECS Transactions, 2013)
Solid state electrochemical techniques have provided insight into the effect of relative humidity on oxygen mass transport properties in Nafion® 117. Specifically, subsequent potential step coulometric measurements taken over a period of time have shown that the act of measurement affects the catalyst-membrane interface. It is postulated that the formation of product water at the interface leads to interactions with the Nafion® 117 surface and results in local domain changes. This effect has been shown to be reversible provided there is adequate rest time between measurements to allow for water diffusion from the interface.

Optimization of the cutting conditions for high speed drilling of woven composites - Meshreki, Mouhab; Hamza, Karim; Nassef, Ashraf O.; Attia, Helmi (Volume 3A: 39th Design Automation Conference, 2013)
The present work proposes a new algorithm for the optimization of cutting parameters in the high speed drilling of woven composites. The cutting parameters under consideration are the feed rate and the spindle speed. Three performance parameters are to be minimized. These are the exit delamination, the surface roughness and the thrust force. These performance parameters are observed experimentally. One of the challenges that face the experimental testing of these parameters is the high cost of the drilling tools and specimen materials. Therefore, the minimization of the number of experimental tests is a necessary requirement. The algorithm presented hybridizes Kriging as a meta-modeling technique with evolutionary multi-objective optimization to optimize the cutting parameters while intelligently selecting the new set of cutting parameters in each iteration. After starting with a factorial design of the search space, and after testing the performance criteria at these points, the algorithm fits a multi-dimensional surface using Kriging. This step is followed by an evolutionary search on the fitted model. The search spreads a population of search points in the direction of better performance criteria as well as in the direction of un-sampled space. The previous two steps are conducted iteratively for a pre-defined number of iterations. In the final iteration, the population of search points is clustered to yield a small number of new points at which the new experiments will be conducted. The whole process is iterated until the maximum number of allowable experiments is achieved. The algorithm is tested using an existing set of previously published experimental data that are dense enough to predict the actual response surface of the performance criteria. Results showed that the algorithm smartly moved into the direction of higher performance criteria with a low number of experimental trials.
Keywords: Drilling; Optimization; Cutting; Woven composites

Optimization of breakwater reconstruction at Mont Louis, Québec - Knox, Paul; Cornett, Andrew; Drouin, Alain (Proceedings, Annual Conference - Canadian Society for Civil Engineering, 2013)
The Port of Mont Louis is located on the south shore of the Gulf of St. Lawrence, roughly 120 km west of Gaspé, Québec. A 450 m long breakwater was constructed on the east side of the bay in 1955 to form a sheltered harbour basin and to serve as a commercial wharf. Since this time, the structure has been exposed to numerous severe storms that have caused considerable damage, and today this important infrastructure asset is in urgent need of repair. In December 2006 the National Research Council of Canada (NRC) was commissioned by Public Works and Government Services Canada (PWGSC) to conduct numerical and physical model studies to guide the design of repair works for the wharf and surrounding breakwater. The proposed repair works were rather complex and nonconventional, as they involved constructing a new rubble-mound breakwater on top of the badly damaged structure. They also involved integrating a dynamically re-shaping (berm-style) armour layer design in some areas together with more conventional statically stable designs in others. Desktop and numerical modeling was performed to help define the nearshore wave conditions used as inputs for the physical modeling. A three-dimensional physical model was subsequently constructed and used to investigate the performance of the proposed repairs under a range of site-specific design conditions, including extreme water levels and harsh wave conditions. This paper summarizes the numerical and physical modelling studies and their important role in optimizing and verifying the breakwater reconstruction proposed for Mont Louis. The physical modelling allowed the proposed designs to be optimized to improve their hydraulic performance (stability), enhance their constructability, and reduce costs where possible.

On-line monitoring and parameter estimation of a Microbial Fuel Cell operated with intermittent connection of the external resistor - Coronado, Javier; Tartakovsky, Boris; Perrier, Michel (IFAC Proceedings Volumes, 2013)
This study describes on-line monitoring and parameter estimation during Microbial Fuel Cell operation with a pulse-width modulated connection of the external resistor (R-PWM mode) at low and high frequencies. Analysis of the output voltage profiles acquired during R-PWM tests showed the presence of slow and fast dynamic components, which can be described by an equivalent circuit model suitable for process monitoring and control applications. To demonstrate the proposed monitoring and parameter estimation procedure, the MFC was operated at several influent concentrations of acetate (carbon source) and an on-line parameter estimation procedure was used for estimating internal resistance and internal capacitance. Furthermore, these parameters were re-estimated at the end of each test yielding similar results. The proposed on-line procedure can be used for real-time process optimization.
Keywords: Microbial Fuel Cell; Real-time monitoring; Parameter estimation; Internal resistance

On the rheocasting of high integrity hollow shape components for automotive applications using 357 aluminum alloy - Samuel, Ehab; Zheng, Chang Qing; Côté, Pascal (Solid State Phenomena, 2013)
Recent studies regarding semi-solid casting as a viable alternative to conventional liquid metal casting have been met with considerable interest. The dual nature of semi-solid materials results in a marked decrease in internal defects otherwise associated with conventional casting methods. In recent years, the National Research Council Canada - Aluminum Technology Centre (NRC-ATC) has dedicated itself to better understanding the behaviour of semi-solid aluminum alloys, notably 357, using the SEED (Swirled Enthalpy Equilibration Device) rheocasting method. SEED is a novel process which relies on the mechanical agitation and cooling of molten aluminum to produce a semi-solid billet. This billet is then injected into a die to yield the desired cast shape. The current work focuses on the rheocasting of a 357 aluminum alloy support bracket, consisting of four rings. Material flow around a ring is known to result in a welding of the two metal fronts. Traces of porosity and oxides can sometimes be found at the weld, unless preventative measures are taken. These include the use of overflows attached to the ring via a web as well as a careful control of the casting parameters. At NRC-ATC, several parts were rheocast and then subjected to both destructive and non-destructive testing, in an effort to better understand the material flow behaviour around these rings. The results obtained are presented herein.
Keywords: 357 aluminum alloy; Hollow shape; Rheocasting; SEED; Semi-solid

Numerical simulation of flow, temperature and composition variation in the snout and sink roll region of continuous galvanizing baths - Ajersch, F.; Ilinca, F.; Goodwin, F. E. (Materials Science and Technology Conference and Exhibition 2013, MS & T 2013, 2013)
The snout and sink roll regions of a continuous galvanizing operation are of critical importance in achieving automotive quality coated steel products. Entrainment of dross particles into the deposited coating originating in the regions of the snout and at the pinch between the strip and the sink roll contribute to the difficulty of maintaining a defect free surface. Previous numerical models have described the flow,temperature and compositional variations in these regions in a conventional operation. In order to optimize the coating quality new numerical simulations were carried out by introducing a pumping system which can direct flow to these specific areas. The effect of circulating bath composition liquid zinc using an industrially tested pumping system directed to the inside surface of the strip within the snout and into the pinch area were analysed. Velocity, temperature and compositional gradients were calculated and compared to the standard configuration not using pumps. The results indicated that the quality of the coated steel can be improved using this system.
Keywords: Continuous galvanizing; Dross minimization; Numerical simulation; Snout pumping

Novel K-band prime focus reflector-coupled focal plane array - Locke, Lisa S.; Bornemann, Jens; Claude, Stéphane (European Microwave Conference, 2013)
A wideband focal plane array (FPA) covering the full K-band (18 - 26.5 GHz) is proposed for use in passive imaging and microwave astronomy. Focal plane arrays are revolutionizing microwave and millimeter-wave imaging by replacing conventional single-pixel feed horns with arrays of planar elements, decreasing the survey time dramatically. The extent and element spacing of a rectangular array is determined by comparing classic and encircled power techniques. A prime focus reflector-feed configuration is considered with f/D=0.45. Far-field performances of arrays of simple Gaussian feeds and also imported Vivaldi feeds, which include mutual coupling between elements, are evaluated by PO/PTD techniques.
Keywords: Antipodal Vivaldi antenna; Focal plane array; K-band; Mutual coupling; Prime focus reflector; Wideband

Neutral assessment of the National Research Council Canada evaluation function - Fraser, Melissa A.; Tremblay, Ghislaine H.; Bourgeois, Isabelle; Lahey, Robert (Canadian Journal of Program Evaluation, 2013)
Federal government departments and agencies are required to conduct a neutral assessment of their evaluation function once every five years under the Treasury Board Secretariat’s Policy on Evaluation (2009). This article describes the National Research Council’s experience conducting the first neutral assessment of its evaluation function. Based on learning from this first assessment, best practices that NRC intends on replicating, as well as lessons learned for future assessments, are discussed. This article may be of interest to both federal and non-federal organizations seeking to conduct a neutral assessment in an effort to improve their evaluation services and products.

Near-infrared photoluminescence of orange color standards – then and now - Zwinkels, Joanne C.; Noël, Mario; Hillman, Sean (Journal of Modern Optics, 2013)
The presence of near-infrared (NIR) photoluminescence has been recently reported in some of the second series of Ceramic Color Standards (CCSII) that are widely used in the calibration and performance evaluation of color measuring instruments. The impact of this photoluminescence effect can cause significant colorimetric errors particularly for broadband measurements using a detector with high spectral responsivity in the NIR region. The magnitude of this effect has been demonstrated for specific color standards and specific instrument systems but has not been unambiguously quantified to allow general predictions or absolute comparisons of different instrument designs or different ceramic tiles. Here we present absolute NIR photoluminescence measurements on three different formulations of the CCSII orange ceramic color standard using the National Research Council of Canada (NRC) Reference Spectrofluorimeter whose spectral range has been recently extended to 1000 nm. The validation for this extended spectral range is shown by comparison of an independent method of instrument calibration using a different combination of physical standards. It is convincingly shown that the two different leaded formulations of this ceramic orange standard issued in 2000 and 2011 have no significant photoluminescence and thus can be used for calibration with any type of spectrophotometer design whereas the unleaded formulation issued in 2011 has significant NIR photoluminescence and should not be used for instrument calibration and validation over an extended range into the NIR for certain spectrophotometers with relatively high throughput in the NIR region, such as a spectrophotometer with polychromatic illumination mode using a xenon source or with monochromatic illumination mode using a Si detector. It is shown that for colorimetric applications, the impact of this NIR fluorescence is only significant for the latter spectrophotometer design with broadband detection with a Si or spectrally flat detector and is negligible with a narrowband PMT detector. These calculated colorimetric results are also consistent with previously estimated colorimetric errors for this type of orange CCSII ceramic tile used to transfer calibration between these two types of detector systems.
Keywords: Ceramic color standard; Colorimetry; NIR; Photoluminescence; Spectrophotometry

Multiscale molecular modeling of degradation phenomena in catalyst layers of polymer electrolyte fuel cells - Malek, Kourosh; Mashio, Tetsuya (Polymer Electrolyte Fuel Cells, 2013)

Multi-leg structures in ice - examining global loading uncertainties - Barker, A.; Sayed, M. (22nd International Conference on Port and Ocean Engineering under Arctic Conditions (POAC 2013), 2013)
The ISO 19906 Arctic Offshore Standard (2010) represents a great advancement for standards as they pertain to Arctic engineering. However, uncertainties remain for a number of topic areas, including global loading on multi-leg structures in ice. These uncertainties include the effects of sheltering, the width of damaged ice and the effect of jamming. Additional uncertainties pertain to the effects of ridge loading and various ice properties. This paper numerically examines some of these uncertainties, through a parametric study approach. The results present the ice forces on a representative structure, as well as broken ice zone widths. The results show that peak loads are associated with ice drift at an angle, as observed in other laboratory and numerical simulations. In addition, loads increase with decreasing clearance between the legs. The results have applications not only for multi-leg oil and gas structures in ice-covered water, but could be further examined in the context of bridge piers and offshore fields of wind turbine towers.

mPUMA: a computational approach to microbiota analysis by de novo assembly of operational taxonomic units based on protein-coding barcode sequences - Links, Matthew G; Chaban, Bonnie; Hemmingsen, Sean M.; Muirhead, Kevin; Hill, Janet E. (Microbiome, 2013)
BACKGROUND: Formation of operational taxonomic units (OTU) is a common approach to data aggregation in microbial ecology studies based on amplification and sequencing of individual gene targets. The de novo assembly of OTU sequences has been recently demonstrated as an alternative to widely used clustering methods, providing robust information from experimental data alone, without any reliance on an external reference database. RESULTS: Here we introduce mPUMA (microbial Profiling Using Metagenomic Assembly, http://mpuma.sourceforge.net), a software package for identification and analysis of protein-coding barcode sequence data. It was developed originally for Cpn 60 universal target sequences (also known as Gro EL or Hsp 60). Using an unattended process that is independent of external reference sequences, mPUMA forms OTUs by DNA sequence assembly and is capable of tracking OTU abundance. mPUMA processes microbial profiles both in terms of the direct DNA sequence as well as in the translated amino acid sequence for protein coding barcodes. By forming OTUs and calculating abundance through an assembly approach, mPUMA is capable of generating inputs for several popular microbiota analysis tools. Using SFF data from sequencing of a synthetic community of Cpn 60 sequences derived from the human vaginal microbiome, we demonstrate that mPUMA can faithfully reconstruct all expected OTU sequences and produce compositional profiles consistent with actual community structure. CONCLUSIONS: mPUMA enables analysis of microbial communities while empowering the discovery of novel organisms through OTU assembly.
Keywords: Operational taxonomic unit; Automated sequence analysis pipeline; 60 kDa chaperonin; Cpn 60; Microbial profiling; Microbiota; Microbiota analysis

Modelling coastal processes at Shippagan Gully inlet, New Brunswick, Canada - Cornett, A.; Provan, M.; Nistor, I; Drouin, A. (Annual Conference of the Canadian Society for Civil Engineering 2013: Know-How - Savoir-Faire, 2013)
This paper describes the development, calibration and application of a numerical model of the hydrodynamic and sedimentary processes at a dynamic tidal inlet known as Shippagan Gully, located on the Gulf of St-Lawrence near Le Goulet, New Brunswick. The new model has been developed to provide guidance concerning the response of the inlet mouth to various potential interventions aimed at increasing navigation safety. The new model is based on coupling the most recent CMS-Flow and CMSWave models developed by the US Army Corps of Engineers. The coupled model is capable of simulating the depth-averaged currents generated within Shippagan Gully and along the neighbouring coastline due to the effects of tides, winds and waves; the transport of non-cohesive sediments; and the resulting changes in seabed morphology. The development of the model and the steps taken to calibrate and validate it against field measurements are described. The application of the model to predict the coastal processes and the response of the inlet mouth to several storms is described and discussed. The influences of storm direction and storm surge on coastal processes is presented and discussed. The research described herein will contribute to an improved understanding of the hydrodynamics and sedimentary processes at strongly ebb-dominated tidal inlets in general and Shippagan Gully in particular.

Mixed gas sorption of CO2/CH4 mixtures in PIM-1 and PTMSP membranes: experiments and modeling - Vopicka, O.; De Angelis, M. G.; Sarti, G. C.; Guiver, M. D. (Separations Division 2013, 2013)
Sorption of pure methane, carbon dioxide and their binary mixtures in two glassy polymers, poly(1-trimethylsilyl-1-propyne) (PTMSP), and the first polymer of intrinsic microporosity (PIM-1), has been studied experimentally and theoretically, at 35.0 ºC. Measurements were obtained on a newly designed pressure decay sorption apparatus for mixtures of gases, having the basic construction according to Sanders et al. [1], but with a more versatile procedure than that used in [1], which allowed to measure sorption isotherms at constant partial pressure of one component of the gas mixture. Indeed this novel method allows one to measure sorption isotherms i) at constant composition of the gaseous phase, ii) at constant fugacity of one component or iii) at constant equilibrium pressure. The first protocol, in particular, allows to mimic better the real constraints faced when dealing with a membrane separation process, where one has a gas stream of fixed composition, in which only the total pressure can be varied, by compression. The pressure decay apparatus is coupled to a gas chromatograph Varian CP-4900 Micro-GC equipped with a capillary column and with a thermal conductivity detector for analysis of the gas phase composition. In the case of PTMSP, the mixture n-C4/CH4 was initially considered, to provide a direct comparison with literature data [2] and validation of the method. Indeed, the sorption of n-C4/CH4mixtures showed a reasonable agreement with the existing mixed gas sorption data [2]. On the other hand, the CO2/CH4mixed sorption data in PTMSP are completely new, and were measured in the range from 0 to 33 atm of total equilibrium pressure, and from 5 to 90 mol.% of carbon dioxide in the gaseous phase. Furthermore, the same characterization of CO2/CH4 mixed sorption was performed in PIM-1: the pressure range inspected was the same as in PTMSP, while the composition of CO2 ranged from 10 to 50 mol.%. PTMSP membrane was cast from a solution of toluene, immersed in methanol and then dried under vacuum before characterization; its density was 0.77±0.01 g/cm3. The PIM-1 membrane was prepared from a filtered ca. 2.0 wt.% chloroform solution of PIM-1 and heated in vacuum at 70 °C, then submerged in methanol and dried under vacuum at 70 °C. The density of pure PIM-1 was (1.143±0.008) g/cm3at 25°C. For both PTMSP and PIM-1, the mixed gas solubility differs significantly from the pure gas value, and, in particular, the solubility of both components is depressed by the presence of the second one, as it often happens in glassy polymers.[3] The solubility selectivity ranges between 2 and 6 for PTMSP and between 5 and 10 for PIM-1. The methane solubility, however, is more significantly depressed by CO2 than that of CO2 is decreased by CH4, therefore the real solubility selectivity (CO2/CH4) for PTMSP and PIM-1 is higher than the ideal solubility selectivity. Such effect becomes more significant with increasing the mole fraction of CO2 in the gaseous phase and with pressure, and is more significant for PIM-1 than for PTMSP. Indeed, the real solubility selectivity becomes 3 times higher than the ideal one in PTMSP for a fraction of 70 mol.% of CO2 in the gas phase, while for PIM-1 such point is reached with a lower concentration of CO2(50 mol.%). Both results indicate the presence of a competition for available polymer matrix sites, which is not surprising due to the nature of physical sorption in glassy matrices, and possibly also of different interactions between polymer and penetrants. To investigate that behavior, the Non-Equilibrium Lattice Fluid model (NELF) was used [3], while the widely used Dual Mode Sorption (DMS) model was also considered as a reference tool. The NELF model, as well as the DMS, does not require additional parameters for the prediction of the mixed gas behavior, and is fully predictive provided a few pure gas sorption data in the polymer matrix. Indeed, binary interaction parameters are the same as in the pure gas case, and the swelling induced by the mixture is estimated from pure gas swelling. Remarkably, in the DMS model, only competition (depression) effects are accounted for, because the mixed gas additional term (positive) appears only in the denominator of the expression for solubility. The NELF model provided quantitative predictions of the mixed gas sorption of CO2 and CH4under pure- and mixed-gas conditions in PTMSP and in PIM-1. The solubility selectivity is also predicted, although with less accuracy, by the NELF model. The DMS model works fairly well in the case of PTMSP, but provides poorer predictions than the NELF model of the mixed gas solubility in PIM-1. Sorption of mixtures of CO2 and CH4 in PTMSP and in PIM-1 was predictable with the NELF model with an accuracy that is comparable to the experimental one, which could reduce the need for the laborious measurements of mixed gas sorption in polymers. Better insights and interpretation of the mixed gas sorption mechanism can also be obtained by using the NELF model.

Microstructure and hardness properties of a diffusion brazed powder metallurgy beta gamma alloy using a TiNi eutectic braze foil - Sawatzky, Trevor; Seo, Dongyi; Hong, Jae-Keun; Saari, Henry (Materials Science & Technology Conference and Exhibition 2013 (MS&T'13), 2013)
A TiNi eutectic braze alloy in foil form is utilized to diffusion braze a powder metallurgy beta gamma alloy with a nominal composition of TiAl-4Nb-3Mn (at%). The parent material is consolidated by a two-step hot isostatic pressing process, followed by a step-cooled solution heat treatment to produce a fully lamellar microstructure with fine lamellae and limited beta phase growth at the colony boundaries. Diffusion brazing experiments are conducted under vacuum at various isothermal holding temperatures and times ranging from 1030C for 30 minutes to 1150C for 70 minutes. The typical microstructures and mechanical properties of the joints are characterized by SEM, EDS, and microhardness measurements. The interfacial morphology of the brazed joints changes primarily with isothermal holding temperature. Microhardness levels reduced with diffusion brazing at 1150 C for 70 minutes due to reduced volume fraction of nickel rich phases and increased volume fraction of the gamma phase at the centerline of the joint.
Keywords: Diffusion brazing; Microhardness; Microstructure; Titanium aluminide

Microfluidic lab on-a-chip devices for high throughput rare cell sorting - Fatanat-Didar, T.; Li, K.; Veres, T.; Tabrizian, M. (European Cells and Materials, 2013)

Microbial competition in polar soils: a review of an understudied but potentially important control on productivity - Bell, Terrence; Callender, Katrina; Whyte, Lyle; Greer, Charles (Biology, 2013)
Intermicrobial competition is known to occur in many natural environments, and can result from direct conflict between organisms, or from differential rates of growth, colonization, and/or nutrient acquisition. It has been difficult to extensively examine intermicrobial competition in situ, but these interactions may play an important role in the regulation of the many biogeochemical processes that are tied to microbial communities in polar soils. A greater understanding of how competition influences productivity will improve projections of gas and nutrient flux as the poles warm, may provide biotechnological opportunities for increasing the degradation of contaminants in polar soil, and will help to predict changes in communities of higher organisms, such as plants.
Keywords: Competition; Arctic; Antarctic; Bacteria; Fungi; Biogeochemistry; Biodegradation; Soil; Microbial communities

Metabolomic analysis of cold acclimation of Arctic Mesorhizobium sp. strain N₃₃ - Ghobakhlou, Abdollah; Laberge, Serge; Antoun, Hani; Wishart, David S.; Xia, Jianguo; Krishnamurthy, Ramanarayan; Mandal, Rupasri (PLoS ONE, 2013)
Arctic Mesorhizobium sp. N₃₃ isolated from nodules of Oxytropis arctobia in Canada’s eastern Arctic has a growth temperature range from 0°C to 30°C and is a well-known cold-adapted rhizobia. The key molecular mechanisms underlying cold adaptation in Arctic rhizobia remains totally unknown. Since the concentration and contents of metabolites are closely related to stress adaptation, we applied GC-MS and NMR to identify and quantify fatty acids and water soluble compounds possibly related to low temperature acclimation in strain N33. Bacterial cells were grown at three different growing temperatures (4°C, 10°C and 21°C). Cells from 21°C were also cold-exposed to 4°C for different times (2, 4, 8, 60 and 240 minutes). We identified that poly-unsaturated linoleic acids 18∶2 (9, 12) & 18∶2 (6, 9) were more abundant in cells growing at 4 or 10°C, than in cells cultivated at 21°C. The mono-unsaturated phospho/neutral fatty acids myristoleic acid 14∶1(11) were the most significantly overexpressed (45-fold) after 1hour of exposure to 4°C. As reported in the literature, these fatty acids play important roles in cold adaptability by supplying cell membrane fluidity, and by providing energy to cells. Analysis of water-soluble compounds revealed that isobutyrate, sarcosine, threonine and valine were more accumulated during exposure to 4°C. These metabolites might play a role in conferring cold acclimation to strain N₃₃ at 4°C, probably by acting as cryoprotectants. Isobutyrate was highly upregulated (19.4-fold) during growth at 4°C, thus suggesting that this compound is a precursor for the cold-regulated fatty acids modification to low temperature adaptation.
Keywords: Fatty acids; Metabolites; Cell metabolism; Gas chromotography; Glycolipids; Phospholipids; Lipids; Neutral lipids

Measurement of energy and timing resolution of very highly pixellated LYSO crystal blocks with multiplexed SiPM readout for use in a small animal PET/MR insert - Thompson, Christopher J.; Goertzen, Andrew L.; Kozlowski, Poitr; Retière, Fabrice; Stortz, Greg; Sossi, Vesna; Zhang, Xuezhu (2013 IEEE Nuclear Science Symposium and Medical Imaging Conference (2013 NSS/MIC), 2013)
Arrays of silicon photo-multipliers (SiPMs) are good candidates for the readout of detectors in PET MR inserts due to their high packing density, efficiency, low bias voltage and insensitivity to magnetic fields. In this study we report the readout performance of SensL SiPM arrays in terms of their ability to resolve all elements of pixellated lutetium oxy-orthosilicate (LYSO) crystals, and their energy and timing resolution. A SensL SB4-300-35-CER SiPM array consisting of sixteen 3 × 3 mm elements were used as light sensor. An LYSO crystal block consisting of 10×10 1.2 mm × 1.2 mm × 6.0 mm crystals on the bottom layer and 9×9 1.2 mm × 1.2 mm × 4.0 mm crystals on the top layer (which is offset by ½ the crystal width) was mounted on the SensL array, and covers over 95% of its area. A DPC encoding multiplexor with HDMI cable readout made by the Triumf Instrumentation group with a footprint suitable for allowing 16 modules to form a ring inside a Brooker 7T MR rodent imager was used as a readout. The HDMI cable supplies power, and provides readout of four channels and the device temperature. The average energy resolution for all 100 crystals in the lower layer was 11.3±1.8% and 10.8±1.2% for the 81 crystals in the upper layer. The average timing resolution for all 100 crystals in the lower layer was 2.52±0.23 nsec. and 2.55±0.23 nsec. for the 81 crystals in the upper layer.
Keywords: PET; Silicon photo-multiplier; Small Animal PET insert for MRI scanner

Marine renewable energy and the plight of dreamers and schemers - Winsor, Fraser; Healy, Mark; Polagye, Brian (Journal of Ocean Technology, 2013)
The article focuses on the efforts of start up investors and companies to enhance their investments in the marine renewable energy (MRE) industry. It states that the framework of the government in the industry should be flexible to help MRE companies lessen financial and technical risks. According to the author, it is also essential that startups have sufficient engineering and science resources to address financial risks.

Magnetism and spintronics in graphene - Dharma-Wardana, M. W. C. (Spintronics in Nanoscale Devices, 2013)

Lipopolysaccharide structure of Helicobacter pylori serogroup O:3 - Altman, Eleonora; Chandan, Vandana; Li, Jianjun; Vinogradov, Evgeny (Carbohydrate Research, 2013)
In this study, we describe a re-investigation of the lipopolysaccharide structure of Helicobacter pylori serogroup O:3. Application of NMR and MS approaches to the analysis of oligosaccharides obtained through degradation of LPS from H. pylori serogroup O:3 by various methods confirmed that its general architecture was identical to that of LPS from H. pylori strains 26695 and SS1 and followed a sequential linear assembly of the α-1,6-glucan, dd-heptan, and O-chain components. Additionally, MALDI-MS analysis demonstrated that a significant proportion of H. pylori serogroup O:3 LPS was terminated with α-1,6-glucan and was not further substituted by dd-heptan and the O-chain polysaccharide.
Keywords: Helicobacter pylori; LPS; Structure; NMR; MS

Internal conversion vs. intersystem crossing – what drives the dynamics of cyclic α,β-enones? - Schalk, O.; Lang, P.; Schuurman, M. S.; Wu, G.; Bradler, M.; Riedle, E.; Stolow, A.; Chergui, M. (EPJ Web of Conferences, 2013)
The origin of ultrafast intersystem crossing and its competitiveness with singlet pathways was studied in cyclic α,β-enones by transient absorption, time-resolved photoelectron spectroscopy and ab initio calculations.

Insertion profiles of 4 headless compression screws - Hart, Adam; Harvey, Edward J.; Lefebvre, Louis-Philippe; Barthelat, Francois; Rabiei, Reza; Martineau, Paul A. (The Journal of Hand Surgery, 2013)
PURPOSE: In practice, the surgeon must rely on screw position (insertion depth) and tactile feedback from the screwdriver (insertion torque) to gauge compression. In this study, we identified the relationship between interfragmentary compression and these 2 factors. METHODS: The Acutrak Standard, Acutrak Mini, Synthes 3.0, and Herbert-Whipple implants were tested using a polyurethane foam scaphoid model. A specialized testing jig simultaneously measured compression force, insertion torque, and insertion depth at half-screw-turn intervals until failure occurred. RESULTS: The peak compression occurs at an insertion depth of −3.1 mm, −2.8 mm, 0.9 mm, and 1.5 mm for the Acutrak Mini, Acutrak Standard, Herbert-Whipple, and Synthes screws respectively (insertion depth is positive when the screw is proud above the bone and negative when buried). The compression and insertion torque at a depth of −2 mm were found to be 113 ± 18 N and 0.348 ± 0.052 Nm for the Acutrak Standard, 104 ± 15 N and 0.175 ± 0.008 Nm for the Acutrak Mini, 78 ± 9 N and 0.245 ± 0.006 Nm for the Herbert-Whipple, and 67 ± 2N, 0.233 ± 0.010 Nm for the Synthes headless compression screws. CONCLUSIONS: All 4 screws generated a sizable amount of compression (> 60 N) over a wide range of insertion depths. The compression at the commonly recommended insertion depth of −2 mm was not significantly different between screws; thus, implant selection should not be based on compression profile alone. Conically shaped screws (Acutrak) generated their peak compression when they were fully buried in the foam whereas the shanked screws (Synthes and Herbert-Whipple) reached peak compression before they were fully inserted. Because insertion torque correlated poorly with compression, surgeons should avoid using tactile judgment of torque as a proxy for compression. CLINICAL RELEVANCE: Knowledge of the insertion profile may improve our understanding of the implants, provide a better basis for comparing screws, and enable the surgeon to optimize compression.
Keywords: Headless compression screw; Insertion depth; Insertion torque; Interfragmentary compression; Scaphoid fracture

Infrared spectra of the NeC₂D₄ and ArC₂D₄ complexes - Rezaei, M.; Michaelian, K. H.; Mckellar, A. R. W.; Moazzen-Ahmadi, N. (Journal of Molecular Spectroscopy, 2013)
Spectra of Ne─C₂D₄ and Ar─C₂D₄ are studied in the ν11 fundamental band region of C₂D₄ (≈2200 cm⁻¹) using a tuneable quantum cascade laser to probe a pulsed supersonic slit jet expansion. The spectra are those of perpendicular bands of near-prolate asymmetric rotors, but with a doubling of transitions due to tunneling. These tunneling splittings are due to hindered internal rotation of C₂D₄ around its C─C axis, and are more prominent for Ne─C₂D₄ than for Ar─C₂D₄. The analysis yields the first direct measurement of the A rotational constants for these complexes, and shows that the vibrational shifts are very small (<0.3 cm⁻¹). Attempts to observe the spectrum of He─C₂D₄ were not successful.
Keywords: Ethylene; Argon; Neon; Infrared spectrum; Dimer; van der Waals; Supersonic jet

Impact sound insulation of hybrid wood-concrete masonry assemblies - Zeitler, Berndt; Schoenwald, Stefan; Sabourin, Ivan (42nd International Congress and Exposition on Noise Control Engineering 2013, INTER-NOISE 2013: Noise Control for Quality of Life, 2013)
As part of a research project to develop design solutions for concrete-masonry buildings for the Canadian market, a study was conducted on the impact and airborne flanking sound insulation performance of hybrid assemblies with concrete masonry walls and wood joist floors. The effect of junction coupling is investigated in an ISO 15712 flanking prediction context. In the paper, predicted flanking path data will be compared to measured data. Recommendations will be made on how appropriate the application of ISO 15712 is on this type of hybrid assembly.

Impact induced detonation of cased explosive - Downes, D.; Nejad Ensan, M.; Bouamoul, A. (Proceedings - 27th International Symposium on Ballistics, BALLISTICS 2013, 2013)
Fragments of aluminium impacting on Composition B explosives encased in rolled homogenous armour (RHA) steel were investigated using the explicit nonlinear finite element method. The investigation focused on shock to detonation simulations of Composition B, with the objective of determining the critical velocity which would generate a shock wave strong enough to cause detonation of the explosive and the resulting pressure profile of the detonation wave. Detonation scenarios at low, intermediate, high impact velocity were investigated. It was observed that a) at intermediate velocities detonation was due to the development of localized hot spots caused by the compression of the explosive from the initial shockwave; b) at high impact velocity, initiation of the explosive was caused by the initial incident wave behind the top casing/explosive interface. c) At low impact velocity, initiation of the explosive may be caused by the increased pressure of reflecting waves against the surfaces of the explosive casing. This case served to show the importance of capturing all confining surfaces correctly as any surface enhance detonation. Advanced features of the simulation includes Arbitrary-Lagrangian-Eulerian (ALE) approach, the Elastic Plastic Hydrodynamic constitutive material model and the Ignition and Growth of Reaction in High Explosive eq uation of state (IGRHE-EOS) to account for the probability that the explosive may not detonate when impacted.

Hybrid polymer-cellulose nanocrystal suspensions as smart materials - Boluk, Y. (TAPPI International Conference on Nanotechnology 2013, 2013)

Hyperfine-induced hysteretic funnel structure in spin blockaded tunneling current of coupled vertical quantum dots at low magnetic field - Leary, A.; Wicha, A.; Harack, B.; Coish, W. A.; Hilke, M.; Yu, G.; Payette, C.; Gupta, J. A.; Austing, D. G. (The Physics of Semiconductors: Proceedings of the 31st International Conference on the Physics of Semiconductors, 2013)
We outline the properties of the hyperfine-induced funnel structure observed in the two-electron spin blockade region of a weakly coupled vertical double quantum dot device. Hysteretic steps in the leakage current occur due to dynamic nuclear polarization when either the bias voltage or the magnetic field is swept up and down. When the bias voltage is swept, an intriguing ∼3 mT wide cusp near 0 T appears in the down-sweep position, and when the magnetic field is swept, the current at 0 T can be switched from "low" to "high" as the bias is increased.
Keywords: Magnetic fields; Polarization; Quantum dot devices; Leakage currents; High voltage; Direct current transmission

How to reveal subsurface defects in Kevlar® composite materials after an impact loading using infrared vision and optical NDT techniques? - Bendada, A.; Sfarra, S.; Genest, M.; Paoletti, D.; Rott, S.; Talmy, E.; Ibarra-Castanedo, C.; Maldague, X. (Engineering Fracture Mechanics, 2013)
An integrated system between infrared vision and optical non-destructive testing techniques can be considered a viable, robust and reliable approach for both aerospace manufacturing and in-service inspections. In this paper, infrared vision is applied in different spectral bands on two impacted panels made of aramid–phenolic composite by applying two different methods, respectively: (1) near and short-wave infrared reflectography and transmittography, and (2) mid-wave active infrared thermography. Furthermore, optical methods, namely digital speckle photography and holographic interferometry, are used as well to highlight the damages due to the impacts on the samples. Some techniques provide more straightforward detection capabilities than others for different defect types.
Keywords: Composites; Debonding; Infrared vision; Optical testing; Defects

High harmonic cutoff energy scaling and laser intensity measurement with a 1.8 μm laser source - Shiner, A. D.; Trallero-Herrero, C.; Kajumba, N.; Schmidt, B. E.; Bertrand, J. B.; Kim, Kyung Taec; Bandulet, H.-C.; Comtois, D.; Kieffer, J.-C.; Rayner, D. M.; Corkum, P. B.; Légaré, F.; et al. (Journal of Modern Optics, 2013)
High harmonic generation in gas targets leads to the production of attosecond pulses. The process of high harmonic generation requires that the gas be ionized by an intense femtosecond laser field. The highest photon energy produced is related to the laser intensity times the wavelength squared. This cutoff is reached only if good phase matching is achieved. Using a laser with a wavelength of 1800 nm, we estimate the laser intensity in the gas jet by recording the ion yield, and simultaneously record the high harmonic spectrum. We show that the cutoff energy matches the measured intensity, confirming that good phase matching is achieved to 100 eV. We also use the ion collector to characterize the spatial size of the gas jet and to measure the confocal parameter of the laser beam, parameters that are useful for numerical modelling.
Keywords: High harmonic generation; Phase matching

Herschel-HIFI observations of high-JCO and isotopologues in star-forming regions: from low to high mass - San José-García, I.; Mottram, J. C.; Kristensen, L. E.; van Dishoeck, E. F.; Yıldız, U. A.; van der Tak, F. F. S.; Herpin, F.; Visser, R.; McCoey, C.; Wyrowski, F.; Braine, J.; Johnstone, D. (Astronomy & Astrophysics, 2013)
CONTEXT. Our understanding of the star formation process has traditionally been confined to certain mass or luminosity boundaries because most studies focus only on low-, intermediate-, or high-mass star-forming regions. Therefore, the processes that regulate the formation of these different objects have not been effectively linked. As part of the “Water In Star-forming regions with Herschel” (WISH) key programme, water and other important molecules, such as CO and OH, have been observed in 51 embedded young stellar objects (YSOs). The studied sample covers a range of luminosities from <1 to >10⁵L⊙. AIMS. We analyse the CO line emission towards a large sample of embedded protostars in terms of both line intensities and profiles. This analysis covers a wide luminosity range in order to achieve better understanding of star formation without imposing luminosity boundaries. In particular, this paper aims to constrain the dynamics of the environment in which YSOs form. METHODS. Herschel-HIFI spectra of the ¹²CO J = 10–9, ¹³CO J = 10–9 and C18O J = 5–4, J = 9–8 and J = 10–9 lines were analysed for a sample of 51 embedded protostars. In addition, JCMT spectra of ¹²CO J = 3–2 and C¹⁸O J = 3–2 extend this analysis to cooler gas components. We focussed on characterising the shape and intensity of the CO emission line profiles by fitting the lines with one or two Gaussian profiles. We compared the values and results of these fits across the entire luminosity range covered by WISH observations. The effects of different physical parameters as a function of luminosity and the dynamics of the envelope-outflow system were investigated. RESULTS. All observed CO and isotopologue spectra show a strong linear correlation between the logarithms of the line and bolometric luminosities across six orders of magnitude on both axes. This suggests that the high-J CO lines primarily trace the amount of dense gas associated with YSOs and that this relation can be extended to larger (extragalactic) scales. The majority of the detected ¹²CO line profiles can be decomposed into a broad and a narrow Gaussian component, while the C¹⁸O spectra are mainly fitted with a single Gaussian. For low- and intermediate-mass protostars, the width of the C¹⁸O J = 9–8 line is roughly twice that of the C¹⁸O J = 3–2 line, suggesting increased turbulence/infall in the warmer inner envelope. For high-mass protostars, the line widths are comparable for lower- and higher-J lines. A broadening of the line profile is also observed from pre-stellar cores to embedded protostars, which is due mostly to non-thermal motions (turbulence/infall). The widths of the broad ¹²CO J = 3–2 and J = 10–9 velocity components correlate with those of the narrow C¹⁸O J = 9–8 profiles, suggesting that the entrained outflowing gas and envelope motions are related but independent of the mass of the protostar. These results indicate that physical processes in protostellar envelopes have similar characteristics across the studied luminosity range.
Keywords: Astrochemistry; Star formation; Protostar; ISM molecules; ISM kinematics; ISM dynamics

Herschel observations of the W3 GMC: clues to the formation of clusters of high-mass stars - Rivera-Ingraham, A.; Martin, P. G.; Polychroni, D.; Motte, F.; Schneider, N.; Bontemps, S.; Hennemann, M.; Men'shchikov, A.; Nguyen Luong, Q.; André, Ph.; Arzoumanian, D.; Bernard, J.-Ph.; et al. (The Astrophysical Journal, 2013)
The W3 GMC is a prime target for the study of the early stages of high-mass star formation. We have used Herschel data from the HOBYS key program to produce and analyze column density and temperature maps. Two preliminary catalogs were produced by extracting sources from the column density map and from Herschel maps convolved to 500 μm resolution. Herschel reveals that among the compact sources (FWHM < 0.45 pc), W3 East, W3 West, and W3 (OH) are the most massive and luminous and have the highest column density. Considering the unique properties of W3 East and W3 West, the only clumps with ongoing high-mass star formation, we suggest a "convergent constructive feedback" scenario to account for the formation of a cluster with decreasing age and increasing system/source mass toward the innermost regions. This process, which relies on feedback by high-mass stars to ensure the availability of material during cluster formation, could also lead to the creation of an environment suitable for the formation of Trapezium-like systems. In common with other scenarios proposed in other HOBYS studies, our results indicate that an active/dynamic process aiding in the accumulation, compression, and confinement of material is a critical feature of the high-mass star/cluster formation, distinguishing it from classical low-mass star formation. The environmental conditions and availability of triggers determine the form in which this process occurs, implying that high-mass star/cluster formation could arise from a range of scenarios: from large-scale convergence of turbulent flows to convergent constructive feedback or mergers of filaments.
Keywords: Dust; Extinction; Infrared stars; Westerhout 3; Individual stars; Early-type stars; Star formation

Genomics, microbiomes, single cell analysis and next-generation sequencing - Köhler, Gerwald A.; Lau, Peter C. K. (Journal of Microbiological Methods, 2013)

Femtosecond laser desorption of thin polymer films from a dielectric surface - Mercadier, Laurent; Peng, Jiahui; Sultan, Yasir; Rayner, David M.; Corkum, Paul B. (CLEO: 2013, 2013)
We desorb polymer films from fused silica with a femtosecond laser and characterize the results by atomic force microscopy. Our study as a function of beam geometry and energy reveals two ways of achieving spatially controlled nanodesorption.

Experimental study of structures subjected to hydrodynamic and debris impact forces - Al-Faesly, T. Q.; Nistor, I.; Palermo, D.; Cornett, A. (Proceedings, Annual Conference - Canadian Society for Civil Engineering, 2013)
An accurate estimation of tsunami-induced forces on nearshore structures is an important step towards the design of tsunami-resilient buildings. The University of Ottawa, in collaboration with the Canadian Hydraulics Centre (CHC) of the National Research Council, located in Ottawa, has established a comprehensive experimental and numerical modeling program focusing on tsunami-structure interaction with the ultimate goal of improving tsunami mitigation methods and strategies. As part of this experimental program, the authors conducted laboratory tests on the impact of extreme hydrodynamic forces and floating debris on two structural models with different cross sections (square and circular). These structures were subjected to supercritical hydraulic bores that are similar to ones generated by broken tsunami waves advancing inland. The structural models were instrumented with sensors capable of recording time histories of the hydraulic bore depth, as well as the lateral displacement, acceleration, pressures, forces, and moments imposed on the two structural models. The bore depth and bore velocity were recorded and analyzed, and the bore-structure interaction was also investigated. The time histories of the impact force resulting from wooden debris hitting the structural models were also recorded and analyzed. The authors further investigated existing formulas provided by the most recent tsunami-resistant engineering design guideline (FEMA P-646, 2012) and the Coastal Construction Manual (FEMA P-55, 2011) to compare the experimentally-recorded hydrodynamic and debris impact forces with current prescriptions.

Experimental studies of mixed-phase sticking efficiency for ice crystal accretion in jet engines - Currie, Thomas C.; Fuleki, Dan; Mahallati, Ali (Transactions of Japanese Society for Medical and Biological Engineering, 2013)
Aircraft jet engines operating at high altitudes in ice crystal clouds can experience operational problems and/or damage resulting from accretion of ingested ice crystals within the compressor. It is believed the ice crystals partially melt, allowing them to stick to internal components. A method for modelling such mixed-phase accretion is required to de-risk new engine designs, modify existing designs with such icing issues and define critical operating points for scrutiny in proposed ice crystal certification tests. This paper presents preliminary results for a modelling approach which treats the accretion process as strictly a sticking phenomenon, ignoring heat transfer, phase change, runback and other location-dependent effects commonly used in the analysis of supercooled water icing. Ice-on-ice growth is described by a sticking efficiency, defined as the fraction of the mixed-phase impinging mass flux which remains on the surface (i.e. sticks). Experimental results are presented for 3 test articles tested in a small mixed-phase icing tunnel located in an altitude chamber (Research Altitude Test Facility or RATFac) at the National Research Council of Canada. These results show that the sticking efficiency is highly correlated with the ratio of liquid water content (LWC) to total water content (TWC) in the freestream, reaching a maximum value of 0.4-0.5 at melt (LWC/TWC) ratios in the approximate range 10-20%, as measured with a multi-element probe. It is shown that sticking efficiencies are largely independent of TWC, Mach number (M) and particle size at normal incidence (i.e. at the stagnation point) at these melt ratios, at least in the limited ranges of these variables investigated, but are strongly dependent on these parameters at oblique impingement angles. It is also shown that accretions can grow to a very large size at an almost constant rate at high levels of TWC. The experimental results are used to develop an erosion-based semi-empirical accretion model which at least partially explains this super-growth phenomenon and predicts most of the experimental results with acceptable fidelity. The model predicts that the almost unlimited growth observed in the experiments is possible at lower Mach numbers (e.g. 0.25) for TWC levels exceeding ~10g/m3, when the sticking efficiency remains finite at all particle impingement angles. The model also predicts that such growth is unlikely for higher Mach numbers (e.g. 0.4), at least for the 45μ (MVD) particles to which the model is applied. Smaller particles will likely extend the Mach number range over which the sticking efficiency remains finite.

Experimental characterization and multi-objective optimization of the orbital drilling process of CFRP - Sadek, A.; Nassef, A. O.; Meshreki, M.; Attia, M. H. (Volume 2B: Advanced Manufacturing, 2013)
Defects associated with drilling of Carbon Fiber-Reinforced Polymers (CFRPs) are of major economic and safety concerns for aerospace manufacturers. One of the most critical defects associated with drilling of CFRP laminates is delamination of layers which can be avoided by keeping the drilling forces below some threshold levels. Orbital Drilling (OD) is an emerging drilling process that exhibits lower cutting forces and temperatures, easier chip removal, higher produced surface quality, longer tool life, and a high possibility for dry machining. The OD process is featured by cyclic engagement and disengagement between the tool and the workpiece whereby a considerable part of the work done by the tool is directed towards the tangential direction while the work done in the axial direction is reduced. This reduces the risk of delamination at the exit. The objective of this research work is to investigate the effect of the OD process key parameters with respect to the produced hole attributes (surface roughness, delamination, and hole accuracy), as well as the cutting forces and temperatures. All the OD tests were performed under dry conditions using a four-flute 6.35 mm end-mill. The cutting forces were recorded using a 3-component dynamometer Kistler 9255B and cutting temperatures were measured using a FLIR ThermoVision A20M Infrared camera at the holes exit. A full factorial design of the experiment was used whereby the feeds varied from 60 to 360 mm/min and the speeds from 6,000 to 16,000 rpm. The test material used was a quasi-isotropic laminate comprising woven graphite epoxy prepreg. Analysis of the results showed 45% reduction in the axial force component in orbital drilling (OD), compared to conventional drilling. None of the holes produced by the entire set of experiments has experienced any entry or exit delamination. ANOVA was used to identify the significance of the controllable variables on the experimental outputs. To overcome the challenge of optimizing the competing parameters of the hole quality attributes while maximizing the productivity, an algorithm was applied by hybridizing Kriging as a meta-modeling technique with evolutionary multi-objective optimization to optimize the cutting parameters.
Keywords: Drilling; Carbon reinforced plastics; Pareto optimization; Experimental characterization

Evaluation of innovative high performance lubricants for compaction of complex powder metallurgy parts - Paris, V.; Thomas, Y.; St-Laurent, S. (Proceedings Euro PM2013 : International Powder Metallurgy Congress & Exhibition, 2013)
A clear trend in the PM community for the past years is the development of increasingly more complex parts. Multi-level, tall and high green density parts are favoured in order to obtain the best mechanical performances while keeping the manufacturing costs as low as possible. To some extent, such advances are dependent on the metal powder feedstock. High performance lubricants added to the metal powder mix should, amongst others, promote a superior die-fill and an easier ejection from the die. This article evaluates the behaviour of lubricant PR-2, a high performance lubricant developed by Rio Tinto Metal Powders. A water-atomised steel powder mix containing 2.0% copper, 0.55% graphite and variable amounts of the high performance lubricant was tested on an industrial press. The press was run in fully automatic mode during extended periods of time and the part-to-part weight variation was measured. The powder was also characterised for its die-filling behaviour. The lubricant is compared to other commonly used PM lubricants such as Acrawax C and Kenolube.

Evaluation of global ice load impacts based on real-time monitoring of ship motions - Nyseth, Håvard; Frederking, Robert; Sand, Bjørnar (Proceedings of the International Conference on Port and Ocean Engineering under Arctic Conditions, 2013)
As part of the ColdTech program, the Norwegian Coastguard vessel KV Svalbard has been equipped with an inertial measurement device (MRU) to record global ship motions in six degrees of freedom during ramming of heavy ice features. The objective of the measurement campaign was to look further into the possibility of using recorded whole-ship motions to evaluate the response of the ship and the global loads acting on the hull for different types of ship-ice interactions. The system has been tested during two expeditions around the Svalbard islands and the Fram Strait in 2011 and 2012. This paper should be considered as an introduction to the measurement campaign, and discusses the authors’ views on the applicability and limitations of such a monitoring system. Although similar measurements have been carried out in earlier projects, the actual usability of the system and the potential for further development to obtain a better understanding of the ice loads and the ship response during ramming have not previously been discussed in detail. The post-processing of the recorded data and further evaluation of the global ice loads derived from the measured ship motions are discussed in brief and exemplified using the recordings from a controlled impact with a distinct ice feature. Detailed discussions and validity of results will however be presented in a separate paper. Assumptions made and uncertainties connected to the proposed procedure are also discussed.

Evacuation in ice: ice loads on a lifeboat during field trials - Ré, António J. Simões; Veitch, Brian (Volume 6: Polar and Arctic Sciences and Technology; Offshore Geotechnics; Petroleum Technology Symposium, 2013)
Full-scale field trials of a conventional lifeboat in pack ice have yielded insights into the design and operation of evacuation craft in ice. The multi-year trials program used an instrumented lifeboat to investigate design considerations such as powering and propulsion, hull form, maneuvering, ice loads and ergonomics. Operational issues that have been examined include ice management for emergency evacuation, coxswain competence and training. This paper focuses on local ice loads measured on the hull during aggressive operations in pack ice. Field measurements are presented and the implications for design and safe operations are discussed.
Keywords: Stress; Ice; Lifeboats

Erratum: The possible contribution of gravity measurements to the difference between the NIST and NRC watt balance results - Newell, D. B.; Liard, J. O.; Inglis, A. D.; Eckl, M. C.; Winester, D.; Silliker, R. J.; Gagnon, C. G. L. (Metrologia, 2013)

ERRATUM: “Studies of variability in proto-planetary nebulae. II.light and velocity curve analyses of IRAS 22272+5435 AND 22223+4327” (2013, ApJ, 766, 116) - Hrivnak, Bruce J.; Lu, Wenxian; Sperauskas, Julius; Van Winckel, Hans; Bohlender, David; Začs, Laimons (The Astrophysical Journal, 2013)

Erratum: “Structure and dynamics of the globular cluster Palomar 13” (2011, ApJ, 743, 167) - Bradford, J. D.; Geha, M.; Muñoz, R. R.; Santana, F. A.; Simon, J. D.; Côté, P.; Stetson, P. B.; Kirby, E.; Djorgovski, S. G. (The Astrophysical Journal, 2013)

Erratum to “On the effect of the peening trajectory in shot peen forming” [Finite Elem. Anal. Des. 69 (2013) 48–61] - Gariépy, A.; Larose, S.; Perron, C.; Bocher, P.; Lévesque, M. (Finite Elements in Analysis and Design, 2013)

Erratum to “Hybrid fire testing for assessing performance of structures in fire – methodology” [Fire Saf. J. 58 (May 2013) 170–179] - Mostafaei, Hossein (Fire Safety Journal, 2013)

Corrigendum to “Effects of synthesis condition on formation of desired crystal structures of doped-TiO₂/carbon composite supports for ORR electrocatalysts” [Electrochim. Acta 77 (2012) 225–231] - Bing, Yonghong; Neburchilov, Vladimir; Song, Chaojie; Baker, Ryan; Guest, Alan; Ghosh, Dave; Ye, Siyu; Campbell, Stephen; Zhang, Jiujun (Electrochimica Acta, 2013)

Cluster-formation in the Rosette molecular cloud at the junctions of filaments (Corrigendum) - Schneider, N.; Csengeri, T.; Hennemann, M.; Motte, F.; Didelon, P.; Federrath, C.; Bontemps, S.; Di Francesco, J.; Arzoumanian, D.; Minier, V.; André, Ph.; Hill, T.; et al. (Astronomy & Astrophysics, 2013)
Keywords: Errata; Addenda; Evolution; HII regions; ISM clouds; ISM structure

Corrigendum to “Carbon-Nb₀.₀₇Ti₀.₉₃O₂ composite supported Pt-Pd electrocatalysts for PEM fuel cell oxygen reduction reaction” [Electrochim. Acta 75 (2012) 220–228] - Ignaszak, Anna; Song, Chaojie; Zhu, Weimin; Wang, Yan-Jie; Zhang, Jiujun; Bauer, Alex; Baker, Ryan; Neburchilov, Vladimir; Ye, Siyu; Campbell, Stephen (Electrochimica Acta, 2013)

Effect of runner and gate configuration on the performance of D-LFT composite parts - Bravo, V. L.; McLeod, M. R.; Porretta, C. (Society of Plastics Engineers - 13th Annual Automotive Composites Conference and Exhibition, ACCE 2013, 2013)
Direct long fibre thermoplastics (D-LFT) composites based on polypropylene and glass fibre (PP/GF) are widely used for the manufacturing of semi-structural and structural automotive applications that include front-end carriers, running boards and door carriers, among other parts. The D-LFT process has a number of advantages when compared to the two step pre-compounded LFT pellet process, of which the most relevant are the cost reduction associated to the elimination of an intermediate step of producing pellets, the flexibility of modifying material formulations in-house at convenience and the reduction of heat and shear history of the material. Among the various configurations commercially available for D-LFT systems, two processes were considered for the present project. In the first process reinforcing fibres are fed and mixed with a molten polymer in a twin screw compounder and then extruded into a rectangular cross-section profile. This extrudate (sometimes referred to as a "log") is automatically cut to a specific length and transferred by a robot arm to a vertical compression moulding press where the polymer/fibre compound is moulded to the desired shape. The moulding can be done by means of direct compression of the log or by its placement into a mould shot-pot device that actuates after the mould is completely closed. A second approach involves the use of an injection moulding compounding unit, comprised of a twin screw compounder and a shot-pot (incorporated this time into the compounding-injection unit) that discharges material through a long nozzle into the sprue of the mould in similar fashion as the conventional injection moulding process. This paper deals with the hypothesis that the differences in the geometry of the flow channels for these two approaches affect the length, dispersion and distribution of fibres in the polymer matrix. It has been well documented in literature that fibre length affects the mechanical properties of the composite material while dispersion and distribution affect the uniformity of these properties ['"]. A systematic analysis of composite material produced with the two processing methods described above was carried out. A Coperion-Dieffenbacher D-LFT system, using a shot-pot mould, and a Coperion-Husky, using the compounding-injection moulding process, were employed to mould identical parts under similar compounding conditions. Samples were taken from the parts for a comparison of the respective fibre lengths and distribution patterns of the two moulding technologies using the micro computed tomography (CT) scanning technique. A characterization of fibre length distribution was performed on the samples using image analysis software after pyrolysis. Resulting mechanical properties were compared to provide a comprehensive picture of the two processing technologies.

Effect of lubricant particle size distribution on the processing and properties of P/M ferrous parts - Thomas, Yannig; Bernier, Fabrice; St Laurent, Sylvain; Paris, Vincent (International Powder Metallurgy Congress and Exhibition, Euro PM 2013, 2013)
The role of lubricants during compaction is crucial and nowadays even more important, due to the increased number of PM parts with higher densities and/or challenging ejection conditions. The development of new lubricants for single compaction requires however an excellent understanding of the lubrication mechanisms and the behaviour of these new compounds. In this paper, the effect of the lubricant particle size distribution on the compaction and ejection behaviour, but also on the static and dynamic properties of ferrous powder metallurgy parts is studied. Indeed, as parts reach higher densities, the influence of the size and shape of pores become dominant on the mechanical performance and particularly fatigue resistance of the parts. Water atomized powder mixes containing different particles sizes of ethylene-bis-stearamide (EBS) lubricant were compacted both on a laboratory press and on an industrial mechanical press at higher speed rates. In addition to compressibility curves and static sintered mechanical properties, complete ejection curves and fatigue tests results are presented.

Does a prestellar core always become protostellar? Tracing the evolution of cores from the prestellar to protostellar phase - Anathpindika, S.; Di Francesco, James (Monthly Notices of the Royal Astronomical Society, 2013)
Recently, a subset of starless cores whose thermal Jeans mass is apparently overwhelmed by the mass of the core has been identified, e.g. the core L183. In the literature, massive cores such as this one are often referred to as ‘super-Jeans cores’. As starless cores are perhaps on the cusp of forming stars, a study of their dynamics will improve our understanding of the transition from the prestellar to the protostellar phase. In this work, we use non-magnetic polytropes belonging originally to the family of the Isothermal sphere. For the purpose, perturbations were applied to individual polytropes, first by replacing the isothermal gas with a gas that was cold near the centre of the polytrope and relatively warm in the outer regions, and secondly, through a slight compression of the polytrope by raising the external confining pressure. Using this latter configuration, we identify thermodynamic conditions under which a core is likely to remain starless. In fact, we also argue that the attribute ‘super-Jeans’ is subjective and that these cores do not formally violate the Jeans stability criterion. On the basis of our test results, we suggest that gas temperature in a star-forming cloud is crucial towards the formation and evolution of a core. Simulations in this work were performed using the particle-based smoothed particle hydrodynamics algorithm. However, to establish numerical convergence of the results we suggest similar tests with a grid scheme, such as the adaptive mesh refinement.
Keywords: Hydrodynamics; Star formation

Disruptive innovations with nanocrystalline cellulose (NCC) and flexible packaging industry - Boluk, Yaman (PLACE Flexible Packaging Symposium 2013: New Technologies, 2013)

Development of a simple and reliable PDMS interconnect for high throughput microfluidic applications - Mu, C. J.; Zhang, Z. Y.; Lin, M.; Cao, X. C. (Microsystem Technologies, 2013)
Microfluidic interconnects act as bridges to connect microscopic channels with macroscopic environments, enabling the microfluidic device to perform its designed functions. In this study, we report a new method to prepare a reliable PDMS interconnect that is able to handle high throughput applications and can be easily incorporated into PDMS microfluidic devices. Using a regular glass plate as an assisting component, we prepare a reliable PDMS interconnect that establishes a strong connection between PDMS surface and an externally inserted stainless steel tubing coupler by using oxygen plasma and epoxy adhesives. In characterizing the resulting PDMS interconnect, we demonstrate that this new PDMS interconnect shows outstanding performances, withstanding flow pressures up to 1.8 MPa in leak-proof tests and pull-out forces up to 100 N, both of which are much higher than previously reported values for PDMS interconnects. In addition, we show that this new epoxy-assisted interconnect is free of contamination and clogging, which results in a highly reproducible fabrication process to prepare a reliable PDMS interconnects. Taken together, we believe that the outstanding performances of the new PDMS interconnect make it a promising candidate for both high throughput and multi-inlet/outlet PDMS microfluidic system applications.
Keywords: Flow rate ratio; PDMS microfluidic channel; PDMS surface; Thick glass substrate; Disposable PDMS; Sheath flow; Bonding strength

Development of a sensor for total temperature and humidity measurements under mixed-phase and glaciated icing conditions - Fuleki, Dan M.; Mahallati, Ali; Knezevici, Daniel C.; Currie, Thomas C.; Macleod, James D. (Transactions of Japanese Society for Medical and Biological Engineering, 2013)
This paper presents a critical development to a prototype sensor that is capable of measuring total air temperature and humidity in a mixed-phase environment, consisting of liquid water droplets and ice crystals. The sensor has fast and stable measurement response under particularly challenging mixed-phase conditions. Total temperature and humidity levels measured with the probe are in good agreement with the results of analytical energy and moisture balances.

Developing performance estimates for high precision astrometry with TMT - Schock, Matthias; Do, Tuan; Ellerbroek, Brent; Herriot, Glen; Meyer, Leo; Suzuki, Ryuji; Wang, Lianqi; Yelda, Sylvana (Third AO4ELT Conference Adaptive Optics for Extremely Large Telescopes Proceedings, 2013)
Adaptive optics on Extremely Large Telescopes will open up many new science cases or expand existing science into regimes unattainable with the current generation of telescopes. One example of this is high-precision astrometry, which has requirements in the range from 10 to 50 micro-arcsec for some instruments and science cases. Achieving these requirements imposes stringent constraints on the design of the entire observatory, but also on the calibration procedures, observing sequences and the data analysis techniques. This paper summarizes our efforts to develop a top down astrometry error budget for TMT. It is predominantly developed for the first-light AO system, NFIRAOS, and the IRIS instrument, but many terms are applicable to other configurations as well. Astrometry error sources are divided into 5 categories: reference source and catalog errors, atmospheric refraction correction errors, other residual atmospheric effects, opto mechanical errors and focal plane measurement errors. Results are developed in parametric form whenever possible. However, almost every error term in the error budget depends on the details of the astrometry observations, such as whether absolute or differential astrometry is the goal, whether one observes a sparse or crowded field, what the time scales of interest are, etc. Thus, it is not possible to develop a single error budget that applies to all science cases and separate budgets are developed and detailed for key astrometric observations. Our error budget is consistent with the requirements for differential astrometry of tens of micro-arcsec for certain science cases. While no show stoppers have been found, the work has resulted in several modifications to the NFIRAOS optical surface specifications and reference source design that will help improve the achievable astrometry precision even further.

Determination of strontium isotope amount ratios in biological tissues using MC-ICPMS - Irrgeher, Johanna; Prohaska, Thomas; Sturgeon, Ralph E.; Mester, Zoltán; Yang, Lu (Analytical Methods, 2013)
A protocol is described for the accurate and precise determination of Sr isotope amount ratios in the TORT-3 candidate lobster hepatopancreas certified reference material (CRM) from the National Research Council Canada. Parameters affecting the separation of Sr and Rb based on a double pass of the dissolved sample matrix through a column packed with Eichrom Sr Spec resin were investigated in detail. Matrix elements were removed and the Rb concentration was reduced to below 0.002% (expressed as the ⁸⁵Rb/⁸⁸Sr intensity ratio) in the purified solutions of TORT-3. Fractionation on the column was eliminated as quantitative recovery (98 ± 4% mean and 1 SD, n = 18) of strontium was obtained. A modified method of standard-sample bracketing with internal normalization for mass bias correction was employed using natural Zr added to both the sample and a solution of NIST SRM 987 used as the bracketing standard. Each iSr/⁸⁶Sr ratio (⁸⁸Sr/⁸⁶Sr, ⁸⁷Sr/⁸⁶Sr and ⁸⁴Sr/⁸⁶Sr) was used to separately calibrate an individual ⁹¹Zr/⁹⁰Zr ratio, which was then used to correct corresponding ⁸⁸Sr/⁸⁶Sr, ⁸⁷Sr/⁸⁶Sr and ⁸⁴Sr/⁸⁶Sr ratios in the sample. The interference from residual ⁸⁴Rb on ⁸⁴Sr was corrected for by simultaneous measurement of ⁸⁵Rb and the use of the IUPAC ⁸⁴Rb/⁸⁵Rb ratio of 0.385706, which was itself mass bias corrected assuming the same mass bias for ⁸⁴Sr/⁸⁶Sr and ⁸⁴Rb/⁸⁵Rb. SRM 987 standard solutions used for method validation returned ratios in good agreement with their certified values, confirming the accuracy of the approach. Absolute isotope amount ratios of 0.056526 ± 0.000048, 0.70937 ± 0.00010 and 8.3824 ± 0.0012 (U, k = 2) for ⁸⁴Sr/⁸⁶Sr, ⁸⁷Sr/⁸⁶Sr, ⁸⁸Sr/⁸⁶Sr, respectively, were obtained in TORT-3. The main contributors to the measurement uncertainties of the TORT-3 Sr isotope ratios are the certified values in SRM 987. Values of −0.442 ± 0.071‰, −1.363 ± 0.036‰ and 0.454 ± 0.030‰ (mean and 1 SD, n = 18) characterize δ⁸⁴/⁸⁶Sr, δ⁸⁷/⁸⁶Sr and δ⁸⁸/⁸⁶Sr in TORT-3, respectively.

Detecting and locating fatigue cracks in a complex wing-box structure using the acoustic emission technique: A verification study - Gagar, Daniel; Martinez, Marcias; Yanishevsky, Marko; Rocha, Bruno; McFeat, Jim; Foote, Peter; Irving, Phil (Structural Health Monitoring 2013: A Roadmap to Intelligent Structures - Proceedings of the 9th International Workshop on Structural Health Monitoring, 2013)
Acoustic Emission (AE) is recognized for its potential as a Structural Health Monitoring (SHM) technique, offering several advantages, such as passive sensing and wide area monitoring, making it particularly attractive for aerospace applications. Realistic structures, like aircraft wings for example, consist of structural elements of complex geometry, manufactured with different materials. Individually these elements may influence the performance of the SHM technique in detecting and locating structural damage. In this research, the capabilities of the AE technique to identify and locate damage in complex structures were assessed. These assessments were performed without disclosure of the damage location to the AE equipment operator. Four piezoelectric AE sensors were mounted on spars of the aircraft wing representative structure prior to conducting a series of constant amplitude loading fatigue tests. One of the spars contained a fatigue crack seeded at a location unknown to the damage monitoring analyst. The sensors monitored AE generated from the spars and event location estimates were obtained using time of flight analysis with a wave velocity value determined experimentally. The AE monitoring successful detected and located the hidden fatigue crack; this was independently verified by three nondestructive testing (NDT) methods.

Coulomb explosion imaging of NO2 dissociation - Ding, Xiaoyan; Lee, Kevin; Staudte, Andre; Villeneuve, David M.; Corkum, Paul B. (Frontiers in Optics 2013, 2013)
We use an intense few-cycle pulse to probe the structural dynamics of pre-dissociating NO2. We show that enhanced ionization gives us preferential access to just-dissociating molecules over not-yet-dissociated - or already-dissociated - molecules.

Corrosion resistance properties of superhydrophobic copper surfaces fabricated by one-step electrochemical modification process - Huang, Ying; Sarkar, D. K.; Gallant, Danick; Chen, X-Grant (Applied Surface Science, 2013)
Superhydrophobic copper surfaces have been prepared by a one-step electrochemical modification process in an ethanolic stearic acid solution. In this work, the corrosion properties of hydrophobic copper surface and superhydrophobic copper surfaces were analyzed by means of electrochemical analyses and compared with that of as-received bare copper substrate. The decrease of corrosion current density (icorr) as well as the increase of polarization resistance (Rp) obtained from potentiodynamic polarization curves revealed that the superhydrophobic film on the copper surfaces improved the corrosion resistance performance of the copper substrate.
Keywords: Corrosion; Stability; Superhydrophobic; Copper; One-step process; SEM; XRD; IRRAS

Corrigendum to “Nb-doped TiO₂/carbon composite supports synthesized by ultrasonic spray pyrolysis for proton exchange membrane (PEM) fuel cell catalysts” [J. Power Sources 220 (2012) 1–9] - Senevirathne, Keerthi; Neburchilov, Vladimir; Alzate, Vanesa; Baker, Ryan; Neagu, Roberto; Zhang, Jiujun; Campbell, Stephen; Chhina, Harmeet; Ye, Siyu (Journal of Power Sources, 2013)

Corrigendum to “Bacterial community evidence for anaerobic degradation of petroleum hydrocarbons in cold climate groundwater” [Cold Reg. Sci. Technol., Volume 86 (2013) pp. 55–68] - Yeung, C. William; Van Stempvoort, Dale R.; Spoelstra, John; Bickerton, Greg; Voralek, John; Greer, Charles W. (Cold Regions Science and Technology, 2013)

Control of the systematic shifts of the strontium ion optical frequency standard at the 10 mHz level - Dube, Pierre; Madej, Alan A.; Tibbo, Maria; Bernard, John E. (2013 Joint European Frequency and Time Forum & International Frequency Control Symposium (EFTF/IFC), 2013)
An overview of the key methods used to reduce the uncertainty of the systematic shifts of the strontium ion optical frequency standard is presented. An uncertainty of 10 mHz at a clock frequency of 445 THz is obtained, limited by the uncertainty of the blackbody radiation shift. The uncertainty estimates of other shifts such as micromotion and electric quadrupole shifts are on the order of 1 mHz or less. The effectiveness of the methods used to reduce or cancel the shifts is illustrated with experiments comparing two ion traps. One has strong micromotion levels while the other, the reference trap, provides good control over the shifts. Despite nominal shifts of 70 Hz in the trap with large micromotion levels, the agreement with the reference trap is at the sub-Hz level.
Keywords: Blackbody radiation; Frequency standards; Measurment uncertainty; Microwave measurement; Strontium; Trapped ions

Compositional and morphological changes of ordered PtxFey/C oxygen electroreduction catalysts - Chen, Liang; Chan, Mickey C. Y.; Nan, Feihong; Bock, Christina; Botton, Gianluigi A.; Mercier, Patrick H. J.; Macdougall, Barry R. (ChemCatChem, 2013)
Changes in the O₂ reduction activity (ORR) and structure of carbon-supported catalysts upon electrochemical stress testing are investigated. Focus is placed on two alloy catalysts of nominal Pt₃Fe/C and Pt₃Fe2/C compositions. Energy dispersive X-ray spectroscopy (EDXS) spot and line analyses reveal a dependence of the Fe composition on the particle size, particularly for the two as-prepared catalysts. The catalyst particles are shown to have a Pt-enriched shell and a PtxFey alloy core. Larger (>≈10 nm) particles are shown to have a higher Fe content that approaches the nominal composition, which suggests that the smaller (<≈6 nm) Pt catalyst particles are more difficult to alloy. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), XRD, and SEM with EDXS show that Fe is lost gradually from the catalyst particles as a result of extensive potential (E)-cycling. Changes upon E-cycling are observed most clearly for the small (<3 nm) particles, in which Fe is almost entirely depleted. However, the catalytic ORR activities remain constant over an extensive cycling period for the PtxFey/C catalysts and the mass ORR activities decrease proportionally with Pt surface area (Apt). The histograms before and after cycling are compared to observed changes in Apt and are discussed in comparison to E-holding experiments. It is concluded that the dissolution of Pt is a strong contributor for the observed decrease in Apt and mass ORR activity for the PtxFey/C catalysts. The continuous transition between Pt oxide formation and its reduction to Pt metal is suggested to play a major role in the degradation of the PtxFey/C catalysts studied in this work.
Keywords: Iron; Platinum; Carbon; Supported catalysts; Reduction

Comparison of T₂ and T₂ *-weighted MR molecular imaging of a mouse model of glioma - Blasiak, Barbara; Barnes, Samuel; Foniok, Tadeusz; Rushforth, David; Matyas, John; Ponjevic, Dragana; Weglarz, Wladyslaw P.; Tyson, Randy; Iqbal, Umar; Abulrob, Abedelnasser; Sutherland, Garnette R.; Obenaus, Andre; et al. (BMC Medical Imaging, 2013)
BACKGROUND Standard MRI has been used for high-grade gliomas detection, albeit with limited success as it does not provide sufficient specificity and sensitivity to detect complex tumor structure. Therefore targeted contrast agents based on iron oxide, that shorten mostly T2 relaxation time, have been recently applied. However pulse sequences for molecular imaging in animal models of gliomas have not been yet fully studied. The aim of this study was therefore to compare contrast-to-noise ratio (CNR) and explain its origin using spin-echo (SE), gradient echo (GE), GE with flow compensation (GEFC) as well as susceptibility weighted imaging (SWI) in T2 and T2* contrast-enhanced molecular MRI of glioma. METHODS A mouse model was used. U87MGdEGFRvIII cells (U87MG), derived from a human tumor, were injected intracerebrally. A 9.4 T MRI system was used and MR imaging was performed on the 10 day after the inoculation of the tumor. The CNR was measured prior, 20 min, 2 hrs and 24 hrs post intravenous tail administration of glioma targeted paramagnetic nanoparticles (NPs) using SE, SWI, GE and GEFC pulse sequences. RESULTS The results showed significant differences in CNR among all pulse sequences prior injection. GEFC provided higher CNR post contrast agent injection when compared to GE and SE. Post injection CNR was the highest with SWI and significantly different from any other pulse sequence. CONCLUSIONS Molecular MR imaging using targeted contrast agents can enhance the detection of glioma cells at 9.4 T if the optimal pulse sequence is used. Hence, the use of flow compensated pulse sequences, beside SWI, should to be considered in the molecular imaging studies.
Keywords: Contrast-to-noise ratio; MRI; Molecular MRI; Contrast agents; Glioma

Classical analysis of Coulomb effects in strong-field ionization of H₂⁺ by intense circularly polarized laser fields - Doblhoff-Dier, Katharina; Dimitriou, Konstantinos I.; Staudte, André; Gräfe, Stefanie (Physical Review A, 2013)
We analyze the distortion of the molecular frame photoelectron angular distributions of H₂⁺ ionized by a strong, circularly polarized infrared laser field using classical trajectory Monte Carlo simulations. We find that the nonisotropic field of the molecular ion rotates the final electron momenta. The degree of distortion from the strong-field approximation's predictions is thereby sensitive to the field strength and the internuclear distance but, counterintuitively, does not necessarily decrease for high field strengths. Furthermore, the distortion also depends crucially on the initial momentum of the classical electron after tunneling, while the exact shape of the ionization rate seems to be less important. A trajectory analysis within our simple model allows us to interpret recent experimental results.

Chemicals from agricultural biomass: chemoenzymatic approach for production of vinylphenols and polyvinylphenols from phenolic acids - Leisch, Hannes; Grosse, Stephan; Morley, Krista; Abokitse, Kofi; Perrin, Florence; Denault, Johanne; Lau, Peter C. K. (Green Processing and Synthesis, 2013)
A two-step chemoenzymatic process for the preparation of polyvinylphenols from phenolic acids (PAs), being abundant aromatic constituents found in agricultural biomass, was developed. In the first step, conversion of 4-hydroxycinnamic acid derivatives to the corresponding vinylphenols, mediated by a recombinant phenolic acid decarboxylase, was evaluated using a variety of bioprocessing technologies that include biphasic whole cell and cell free extract biotransformations, a combination of biocatalyst with adsorbent resins for in situ product recovery, and fixed bed reactors using immobilized whole cells. The best yield (90%) with a high space time yield of 4.83 g/l/h was the result of a combination of crude enzyme extracts of the recombinant Escherichia coli (E. coli) with water immiscible organic solvents such as toluene. In the second step, cationic and radical polymerizations were tested to produce polyvinylguaiacol (PVG) from vinyl phenols. Characterization of PVG by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and nanoindentation test are reported here for the first time. The feasibility of the chemoenzymatic process for the production of aromatic polymers from biomass was demonstrated by the production of polymers from a mixture of ferulic acid (FA) and p-coumaric acid (pCA), obtained from alkaline hydrolysis of corn bran. Interestingly, nanoindentation tests showed that both PVG and “mixed” PVG polymers showed significantly higher performances than a commercial polystyrene polymer.
Keywords: Biorefinery; Biotransformation; Chemoenzymatic synthesis; Green polymers; Phenolic acids

Characteristics of H13 tool steel coatings by pulsed Nd:YAG laser cladding - Wang, Shaodong; Chen, Jianyin; Xue, Lijue (TMS2013 Annual Meeting Supplemental Proceedings, 2013)
AISI H13 hot-work tool steel has a wide application for mold/die of die casting, hot forging, hot extrusion, hot stamping and plastic injection molding, due to its high toughness, high hot hardness and high thermal fatigue resistance. Laser cladding, a material additive technology, can be used to apply various functional coatings and to repair/reconfigure tool/die. H13 tool steel was successfully laser-clad on carbon steel substrates at room temperature. The microstructure of as-clad coating showed a refined dendritic structure due to fast cooling and rapid solidification. X-ray diffraction (XRD) phase identification revealed that the coating consisted of a majority of martensite phase plus certain amount of retained austenite phase (∼ 20 vol%). Tensile residual stresses were measured in the as-clad H13 coating. The average value of Vickers hardness in the as-clad coating is about 575 Hv0.05. Wear resistance evaluation using pin-on-disc sliding wear testing showed that the wear resistance of as-clad H13 steel coating was similar to or slightly better than that of hardened wrought H13 steel (HRC 54) plate under the wear test condition used in this study, but the wear mechanisms are significantly different.
Keywords: Laser cladding; Coating; Pulsed Nd:YAG laser; H13 tool steel

Changes in order parameters associated with ceramide-mediated membrane reorganization measured using pTIRFM - Carter Ramirez, Daniel M.; Jakubek, Zygmunt J.; Lu, Zhengfang; Ogilvie, William W.; Johnston, Linda J. (Langmuir, 2013)
The enzymatic generation of ceramide has significant effects on the biophysical properties of lipid bilayers and can lead to the extensive reorganization of cell membranes. We have synthesized and characterized a headgroup-labeled fluorescent lipid probe (NBD-ceramide, NBD-Cer) and demonstrated that it can be used for polarized total internal reflection fluorescence microscopy experiments to probe changes in membrane order that result from ceramide incorporation. NBD-Cer measures significantly higher order parameters for the liquid-ordered (Lₒ) domains (〈P₂〉 = 0.40 ± 0.03) than for the liquid-disordered phase (Ld, fluid, 〈P₂〉 = 0.22 ± 0.02) of phase-separated bilayers prepared from egg sphingomyelin, dioleolyphosphatidylcholine, and cholesterol mixtures. The probe also responds to changes in packing induced by the direct incorporation of ceramide or the variation in the ionic strength of the aqueous medium. Order parameter maps obtained after enzyme treatment of bilayers with coexisting Lₒ and Ld phases show two distinct types of behavior. In regions of high enzyme activity, the initial Lₒ/Ld domains are replaced by large, dark features that have high membrane order corroborating previous hypotheses that these are ceramide-enriched regions of the membrane. In areas of low enzyme activity, the size and shape of the Lo domains are conserved, but there is an increase in the order parameter for the initial Ld phase (〈P₂〉 = 0.30 ± 0.01). This is attributed to the incorporation of ceramide in the Lo domains with the concomitant expulsion of cholesterol into the surrounding fluid phase, increasing its order parameter.

Challenges and opportunities for bacterial vaccine development in the 21st Century - Duvvuri, Venkata R.; Barreto, Luis; Wu, Jianhong; Tsang, Raymond S. W. (Current Pharmaceutical Biotechnology, 2013)
With the convergence of modern technology in genomics, proteomics, carbohydrate, protein and lipid biochemistry as well as decades of experience in vaccine development and delivery of immunization programs, the Global Vaccine Action Plan has declared 2011 to 2020 as 'The Decade of Vaccines'. This review focuses on bacterial vaccines and summarises the current state of vaccinology in bacteriology and looks forward to the potential of how the newer technologies can impact our knowledge of bacterial diseases and their control through vaccine development. The major breakthroughs in the last couple of decades include low cost high throughput genomics, proteomics, cellular immunology and the delicate network of immune-cytokines, bioinformatics, immune-informatics, and disease modelling. Together, these newer developments can provide a real impact on our understanding of infectious diseases and their control by vaccination.
Keywords: Bacterial diseases; Genomics; Immunomics; Mathematical biology; Proteomics; Vaccinology

Can VIP be an alternative solution for energy retrofit for enhancing the thermal performance of wood-frame walls? - Saber, Hamed H.; Maref, Wahid; Gnanamurugan, Ganapathy; Nicholls, Mike (Thermal Performance of the Exterior Envelopes of Whole Buildings - 12th International Conference, 2013)
Field monitoring of the dynamic heat transmission characteristics of residential 2 × 6 wood-frame wall systems that had been retrofitted using vacuum insulation panels (VIPs) with glass fiber cores and extruded polystyrene foam (XPS) panels were undertaken in 2011-2012 at the Field Exposure of Walls Facility (FEWF) of the NRC Construction. The main objective of this research was to evaluate the steady-state and transient thermal performance of three wall assemblies (4 ft × 6 ft), two of which incorporated VIPs within an XPS tongue and groove (T&G) configuration and VIPs within an XPS clip-on (C-O) configuration, and a third assembly incorporating only XPS. The three wall assemblies were installed in the FEWF for one year cycle of exposure to outdoor natural weather conditions. The NRC's hygrothermal model, hygIRC-C, was validated against the measured data. Results showed that the model predictions were in good agreement with the experimental data. Given that the VIP could be punctured during the installation process (e.g., inadvertent use of fasteners in wall assembly) or may fail during normal operating conditions or due to imperfection during the manufacturing process, the numerical model was used to conduct parametric analyses in order to predict the thermal resistance (R-value) in cases where one or more VIPs failed. In the final phase of this study, the model was used to predict the yearly cumulative heat losses from the respective wall systems. It is important to point out that the aging effect and the effect of the thermal bridging due to the envelope (i.e., skin) of the VIPs are not accounted for in this study. However, sensitivity analysis of the thickness and thermal conductivity of the VIP envelope was conducted in this paper to investigate the effect of these parameters on the effective R-values of VIP. Results showed that the yearly cumulative heating loads for the XPS retrofit wall specimen was 69.9% and 78.8%, respectively, greater than that obtained for the T&G VIP retrofit wall specimen and the C-O VIP retrofit wall specimen. Furthermore, the results showed that the effect of the furred-airspace assembly in the C-O VIP retrofit wall specimen when the emissivity of all surfaces that bounded the airspace was assumed to be 0.9 resulted in a reduction in the yearly heating load by 5% compared to the T&G VIP retrofit wall specimen without furred-airspace.
Keywords: Vacuum Insulation Panel (VIP); Thermal resistance; Thermal performance; Retrofit; Wood-frame wall systems; Energy savings.

A data-driven method for predicting structural degradation using a piezoceramic array - Mulligan, Kyle R.; Yang, Chunsheng; Quaegebeur, Nicolas; Masson, Patrice (International Journal of Prognostics and Health Management, 2013)
There is a growing use of carbon fiber reinforced polymers (CFRPs) in modern airframes with still a limited understanding of the in-service behavioral characteristics of these structures. Structural Health Monitoring (SHM) technologies that use surface-bonded piezoceramic (PZT) transducers to generate and measure guided waves within these structures have demonstrated promising damage detection and localization results and potential for data gathering in data-driven damage prognosis. This paper investigates the development of a data-driven SHM based damage prognosis system for estimating remaining useful life (RUL) of CFRP coupons following damage initiation. A robust and realistic laboratory data gathering methodology is introduced as a building block for evaluating the feasibility of data-driven damage prognosis for in-service aerospace structures. Data are gathered using a PZT-based SHM system. Using the gathered raw guided wave signals, a number of time and frequency domain features are first extracted which are derived from existing damage imaging and detection algorithms. Then, using various combinations of the feature sets as inputs to generic data mining algorithms, the paper presents estimates of the predicted RUL against actual damage diameter progression.
Keywords: SHM; PZT; data-driven; damage prognosis; drop-weight impacting; composite.; data mining; machine learning

Bacterial growth at −15 °C; molecular insights from the permafrost bacterium Planococcus halocryophilus Or1 - Mykytczuk, Nadia C. S.; Foote, Simon J.; Omelon, Chris R.; Southam, Gordon; Greer, Charles W.; Whyte, Lyle G. (The ISME Journal, 2013)
Planococcus halocryophilus strain Or1, isolated from high Arctic permafrost, grows and divides at −15 °C, the lowest temperature demonstrated to date, and is metabolically active at −25 °C in frozen permafrost microcosms. To understand how P. halocryophilus Or1 remains active under the subzero and osmotically dynamic conditions that characterize its native permafrost habitat, we investigated the genome, cell physiology and transcriptomes of growth at −15 °C and 18% NaCl compared with optimal (25 °C) temperatures. Subzero growth coincides with unusual cell envelope features of encrustations surrounding cells, while the cytoplasmic membrane is significantly remodeled favouring a higher ratio of saturated to branched fatty acids. Analyses of the 3.4 Mbp genome revealed that a suite of cold and osmotic-specific adaptive mechanisms are present as well as an amino acid distribution favouring increased flexibility of proteins. Genomic redundancy within 17% of the genome could enable P. halocryophilus Or1 to exploit isozyme exchange to maintain growth under stress, including multiple copies of osmolyte uptake genes (Opu and Pro genes). Isozyme exchange was observed between the transcriptome data sets, with selective upregulation of multi-copy genes involved in cell division, fatty acid synthesis, solute binding, oxidative stress response and transcriptional regulation. The combination of protein flexibility, resource efficiency, genomic plasticity and synergistic adaptation likely compensate against osmotic and cold stresses. These results suggest that non-spore forming P. halocryophilus Or1 is specifically suited for active growth in its Arctic permafrost habitat (ambient temp. ~−16 °C), indicating that such cryoenvironments harbor a more active microbial ecosystem than previously thought.
Keywords: Cryophile; Permafrost; Cold-active; Cold/osmotic adaptation; Subzero environments

Attosecond science and technology - Corkum, P. B. (The European Conference on Lasers and Electro-Optics, 2013)

Astronomical Photometry - Stetson, Peter B. (Planets, Stars and Stellar Systems, 2013)
Astronomers use the term “photometry” to refer to the precise measurement of the apparent brightness of astronomical objects in particular specified ranges of electromagnetic wavelength in and near the optically visible band. Historically, this task has been most commonly carried out with the human eye, photographic plates, photomultiplier tubes, and – most recently as of this writing – charge-coupled devices. At wavelengths significantly shorter or longer than the optical region, different detector technologies must be used, and some other term than “photometry” is often used to name the process.

Application of picosecond laser for polishing of AISI H13 tool steel sample prepared by micro milling - Khalid Hafiz, Abdullah M.; Bordatchev, Evgueni V.; Tutunea-Fatan, Remus O. (41st North American Manufacturing Research Conference 2013, 2013)
This paper explores the applicability of picosecond laser (ps) in laser micro polishing (LμP) of AISI H13 tool steel. The melting regime associated with this process was determined experimentally through the variation of the focal offset in order to attain a desired fluence level. To ensure the consistency and certainty of initial surface geometry, the surface was prepared through a micro milling operation with a step-over of 50 μm and scallop height of 2 μm. The LμP experiments were performed at 5 different fluence levels of the melting regime obtained through setting of the focal point at 5 different distances. The polishing performance was evaluated based on the distribution of line profiling average surface roughness (Ra) at various spatial wavelength intervals. Additional statistical metrics such as material ratio function and power spectral density function were also determined in order to establish the process parameters associated with best achievable surface finish. Finally, as a demonstration of the applicability of ps LμP process, a flat micro milled area was polished using optimum process parameters. This operation yielded in 68% surface quality improvement as quantified through the reduction of the areal topography surface roughness (Sa) from 0.53 urn to 0.17 μm.

Assessment of fibre optic sensor architectures for structural health monitoring - Rocha, B.; Barazanchy, D.; Sevenois, R.; Guo, H.; Xiao, G.; Mrad, N. (Structural Health Monitoring 2013: A Roadmap to Intelligent Structures, 2013)
Fibre Optic Sensors (FOS) present several advantages over their conventional electrical counterparts for Structural Health Monitoring (SHM) of aerospace structures. These sensors are dimensionally small and can be readily embedded into composite structures, or bonded to their surface with minimal effect on weight or aerodynamic characteristics. They also do not generate, and are immune, to Electro-Magnetic Interference (EMI), thus they do not affect neighboring electrical systems or avionics. Fiber Optic Sensors have been widely used for load monitoring in discrete or distributed architectures. Additionally, Fibre Bragg Grating (FBG) sensors, a family of FOS, have been explored for the detecti on of material acoustic waves and damage. Three sensing system configurations, coupled with the use of FBGs, have been studied and reported in the literature for the detection of material acoustic waves; namely, (1) the use of tunable lasers as light source and photodiodes as the light sensors; (2) Broad Band light Sources (BBS) and Arrayed Waveguide Gratings (AWG); and (3) BBS with cascaded, or pairs of phase-shifted FBGs. The first two configurations also offer the ability to perform load monitoring, through strain measurement, in addition to material acoustic wave and damage detection. In an effort to advance the field of Structural Health Monitoring and its implementation in aircraft applications, these three sensing system architectures were evaluated for their capability and ease for the detection of material acoustic waves and damage. Tests were performed using a realistic and aircraft representative skin composite panel, a quasi-isotropic Carbon Fibre Reinforced Polymer (CFRP) skin panel. In the performed evaluati on, material acoustic waves generated by a piezoceramic transducer were accurately and reliably detected using the first (1) and last (3) techni ques. The first architecture was implemented effortlessly and the last presented, inherently, less complexity. The use of the AWG, in the second (2) architecture, presented comparativel y additional challenges to the detection of the generated acoustic waves due to the requirement for a high power light source. As a result of this evaluati on, the first (1) technique was subsequently selected and assessed in damage detection trials with promising results. Due to the demonstrated success of these trials, the experimental composite skin panel, along with the demonstrated damage detecti on technique, are being integrated into the SHM infrastructure being developed at the National Research Council Canada (NRC). This infrastructure consists of structural platforms that range in complexity from a simple 2 m long aluminium beam to full scale aircraft structures - a CF188 wing and a Bell 206 helicopter tail boom. Additionally, such infrastructure offers full scale evaluations and testing of damage detection techniques and technologies and SHM capabilities employing realistic loads and spectra optionally in varying environment conditions.

Assessment of acoustic performance of composite structures with viscoelastic treatments - Ghinet, Sebastian; Osman, Haisam; Grewal, Anant (42nd International Congress and Exposition on Noise Control Engineering 2013 (INTER-NOISE 2013): Noise Control for Quality of Life, 2013)
The main objective of the work is to assess the acoustic performance of viscoelastic treatments versus the case when the treatment is incorporated as an equivalent added mass layer in various configurations of isotropic or composite structures under diffuse field excitation. The Discrete Laminate Method (DLM) was used in a Transfer Matrix Method (TMM) framework to compute the sound transmission loss of the structure with added noise control treatment. The numerical approach was compared with numerical results from literature and experimental data and was shown to accurately predict the sound transmission loss of composite structures with incorporated noise control treatments. Moreover, parametric studies of various configurations were considered in order to highlight promising behavioral trends for optimal noise control treatments design.
Keywords: Composite structures; Noise; Porous materials; Vibration; Viscoelastic materials

Artificial neural networks for predicting 3D protein shapes from amino acid sequences - Viktor, Herna L.; Paquet, Eric; Zhao, Jing (The 2013 International Joint Conference on Neural Networks (IJCNN), 2013)
Research has shown that the functionalities of proteins are largely influenced by their three dimensional (3D) shapes. This observation is especially relevant in drug design, where the knowledge of the 3D structure of a protein enables pharmacologists to select the best binding proteins when aiming to moderate functions. However, a relatively small number of 3D shapes are known. In contrast, amino acid sequences may be acquired through very efficient automated, high throughput experimental methods and the amino acid sequences of a vast number of proteins have therefore been identified. It follows that it is important to address this knowledge gap. To this end, this paper introduces an approach to predict the 3D shapes of proteins, utilizing feed-forward artificial neural networks. Our novel solution allows one to learn the representations of the 3D shape associated with a protein by starting directly from its amino acid sequence descriptors. Once a neural network is trained, our search engine enables one to retrieve the closest known 3D shape associated with an unknown, so-called query protein. We evaluate the performance of our approach against the Protein Data Bank (PDB), by considering proteins from a diverse set of families. Our results indicate that our system is able to accurately find the most similar protein structures for a wide variety of protein 3D shapes and diverse protein family sizes.
Keywords: Bioinformatics; Computer graphics; Neural nets; Proteins

Application of hybrid micro-cogeneration system—Thermal and power energy solutions for Canadian residences - Entchev, E.; Yang, L.; Szadkowski, F.; Armstrong, M.; Swinton, M. (Energy and Buildings, 2013)
This paper presents results from a field trial with a hybrid micro-cogeneration system applied to satisfy both thermal and power needs of a typical Canadian detached house. The hybrid system consists of an internal combustion engine integrated with a high efficiency furnace. It was installed, integrated with the rest of the mechanical systems and demonstrated at the Canadian Center for Housing Technology (CCHT). Cost analysis was performed to examine the economics of such systems in relation to different price structures imposed by the electric utilities. The study revealed that the hybrid micro-cogeneration system performed reliably and generated both heat and power with high efficiency during the heating season and was able to satisfy the heating demand under very cold weather conditions. The power generated by the system was first directed to the house satisfying 50% of the electric load with the other 50% being exported to the grid. The project demonstrated that micro-cogeneration systems when sized to meet the base electric load and design thermal load of the residence are a valuable alternative to the central power generation plants and are able to reliably satisfy the house thermal/power demand even under extreme cold conditions.
Keywords: Hybrid micro-cogeneration system; Micro CHP; Internal combustion engine; High efficiency furnace; Load profiles; Control strategies

Analysis of residual strain profiles in distorted aluminum engine blocks by neutron diffraction - Lombardi, Anthony; Ravindran, Comondore (Ravi); Sediako, Dimitry; Mackay, Robert (SAE Technical Papers, 2013)
In recent years, light weight components have been an area of significant importance in automotive design. This has led to the replacement of steel and cast iron with aluminum alloys for many automotive components. For instance, Al-Si alloys have successfully replaced nodular and gray cast iron in the production of large automotive components such as engine blocks. However, excessive residual strain along the cylinder bores of these engine blocks may result in cylinder distortion during engine operation. Therefore, in this study, neutron diffraction was used to evaluate residual strain along the aluminum cylinder bridge and the gray cast iron liners of distorted and undistorted engine blocks. The strains were measured in the hoop, radial, and axial orientations. The results suggest that the residual strain along the aluminum cylinder bridge of the distorted engine block was tensile for all three measured components. Conversely, the undistorted engine block had compressive strains in the axial and radial orientations, while the hoop direction had tensile strain of lower magnitude. The gray iron liners, meanwhile, had compressive residual strain for both engine blocks. The variation in strain, specifically in the aluminum cylinder bridge, suggests that permanent dimensional distortion in the cylinders was triggered by tensile residual stress when exposed to service conditions.
Keywords: Analysis methodologies; Aluminum alloys; Aluminum engines

Analysis of residual strain profiles in distorted aluminum engine blocks by neutron diffraction - Lombardi, Anthony; Ravindran, Comondore (Ravi); Sediako, Dimitry; Mackay, Robert (SAE International Journal of Materials and Manufacturing, 2013)
In recent years, light weight components have been an area of significant importance in automotive design. This has led to the replacement of steel and cast iron with aluminum alloys for many automotive components. For instance, Al-Si alloys have successfully replaced nodular and gray cast iron in the production of large automotive components such as engine blocks. However, excessive residual strain along the cylinder bores of these engine blocks may result in cylinder distortion during engine operation. Therefore, in this study, neutron diffraction was used to evaluate residual strain along the aluminum cylinder bridge and the gray cast iron liners of distorted and undistorted engine blocks. The strains were measured in the hoop, radial, and axial orientations. The results suggest that the residual strain along the aluminum cylinder bridge of the distorted engine block was tensile for all three measured components. Conversely, the undistorted engine block had compressive strains in the axial and radial orientations, while the hoop direction had tensile strain of lower magnitude. The gray iron liners, meanwhile, had compressive residual strain for both engine blocks. The variation in strain, specifically in the aluminum cylinder bridge, suggests that permanent dimensional distortion in the cylinders was triggered by tensile residual stress when exposed to service conditions.
Keywords: Analysis methodologies; Aluminum alloys; Aluminum engines

An isometry-invariant spectral approach for protein-protein docking - De Youngster, Dela; Paquet, Eric; Viktor, Herna; Petriu, Emil (13th IEEE International Conference on BioInformatics and BioEngineering, 2013)
The protein docking problem refers to the task of predicting the appropriate matching of one protein molecule (the receptor) to another (the ligand), when attempting to bind them to form a stable complex. Research shows that matching the three-dimensional geometric structures of proteins plays a key role in determining a so-called docking pair. However, the active sites which are responsible for the binding do not always present a rigid-body shape matching problem. Rather, they may undergo deformations when docking occurs, which complicates the process. To address this issue, we present an isometry-invariant and topologically robust partial shape descriptor method for finding complementary protein sites. Our method employs Heat Kernel Signature shape descriptors which are based on the diffusion of heat on surfaces. Our experimental results against the Protein-Protein Benchmark 4.0 demonstrate the viability of our approach.
Keywords: molecular biophysics; deformation; molecular configurations; proteins; spectral analysis

An accessible, large-print, listening and talking e-book to support families reading together - Attarwala, Abbas; Munteanu, Cosmin; Baecker, Ronald (Proceedings of the 15th International Conference on Human-computer interaction with mobile devices and services - MobileHCI 2013, 2013)
Reading is an activity that is not only informative or pleasurable, but can have significant social benefits. Especially in a family setting, it is part of the interaction between children and their parents, it helps create a bond between children and their grandparents, and even bring adults and their older parents closer. However, with families increasingly living or spending time in different locations or managing busy schedules that afford very little time together, the social opportunities enabled by reading are often lost. Furthermore, reading can be a challenge for older adults or for those with impaired eyesight. To address these problems, we are proposing ALLT -- an Accessible, Large-Print, Listening and Talking e-book. ALLT is a tablet-based e-reading application that enhances the capabilities of e-book readers through customizable and intelligent accessibility features. It provides support for asynchronous "reading together" by synchronizing the audio recording of one user with the text that is later read by another user. This addresses the needs of a variety of users, from visually impaired adults reading together with a loved one, to children being able to replay an interactive story previously read together with their grandparents. In this demo paper we present ALLT's features and detail how they support asynchronously reading together.
Keywords: Collaborative reading; Aging; Visual impairment; Assistive technology

Aflatoxin, fumonisin and Shiga toxin-producing Escherichia coli infections in calves and the effectiveness of Celmanax®/Dairyman’s Choice™ applications to eliminate morbidity and mortality losses - Baines, Danica; Sumarah, Mark; Kuldau, Gretchen; Juba, Jean; Mazza, Alberto; Masson, Luke (Toxins, 2013)
Mycotoxin mixtures are associated with Shiga toxin-producing Escherichia coli (STEC) infections in mature cattle. STEC are considered commensal bacteria in mature cattle suggesting that mycotoxins provide a mechanism that converts this bacterium to an opportunistic pathogen. In this study, we assessed the mycotoxin content of hemorrhaged mucosa in dairy calves during natural disease outbreaks, compared the virulence genes of the STECs, evaluated the effect of the mucosal mycotoxins on STEC toxin expression and evaluated a Celmanax®/Dairyman’s Choice™ application to alleviate disease. As for human infections, the OI-122 encoded nleB gene was common to STEC genotypes eliciting serious disease. Low levels of aflatoxin (1–3 ppb) and fumonisin (50–350 ppb) were detected in the hemorrhaged mucosa. Growth of the STECs with the mycotoxins altered the secreted protein concentration with a corresponding increase in cytotoxicity. Changes in intracellular calcium indicated that the mycotoxins increased enterotoxin and pore-forming toxin activity. A prebiotic/probiotic application eliminated the morbidity and mortality losses associated with the STEC infections. Our study demonstrates: the same STEC disease complex exists for immature and mature cattle; the significance of the OI-122 pathogenicity island to virulence; the significance of mycotoxins to STEC toxin activity; and, finally, provides further evidence that prebiotic/probiotic applications alleviate STEC shedding and mycotoxin/STEC interactions that lead to disease.
Keywords: Shiga toxin-producing Escherichia coli; Mycotoxin; Prebiotic; Probiotic; Virulence

Acute physiological stress down-regulates mRNA expressions of growth-related genes in Coho salmon - Nakano, Toshiki; Afonso, Luis O. B.; Beckman, Brian R.; Iwama, George K.; Devlin, Robert H.; Fuentes, Juan (PLoS ONE, 2013)
Growth and development in fish are regulated to a major extent by growth-related factors, such as liver-derived insulin-like growth factor (IGF) -1 in response to pituitary-secreted growth hormone (GH) binding to the GH receptor (GHR). Here, we report on the changes in the expressions of gh, ghr, and igf1 genes and the circulating levels of GH and IGF-1 proteins in juvenile coho salmon (Oncorhynchus kisutch) in response to handling as an acute physiological stressor. Plasma GH levels were not significantly different between stressed fish and prestressed control. Plasma IGF-1 concentrations in stressed fish 1.5 h post-stress were the same as in control fish, but levels in stressed fish decreased significantly 16 h post-stress. Real-time quantitative PCR (qPCR) analysis showed that ghr mRNA levels in pituitary, liver, and muscle decreased gradually in response to the stressor. After exposure to stress, hepatic igf1 expression transiently increased, whereas levels decreased 16 h post-stress. On the other hand, the pituitary gh mRNA level did not change in response to the stressor. These observations indicate that expression of gh, ghr, and igf1 responded differently to stress. Our results show that acute physiological stress can mainly down-regulate the expressions of growth-related genes in coho salmon in vivo. This study also suggests that a relationship between the neuroendocrine stress response and growth-related factors exists in fish.
Keywords: Fish physiology; Salmon; Gene expression; Hydrocortisone; Marine fish; Pituitary gland; Growth hormone; Blood plasma

A ΔclpB mutant of Francisella tularensis subspecies holarctica Strain, FSC200, is a more effective live vaccine than F. tularensis LVS in a mouse respiratory challenge model of tularemia - Golovliov, Igor; Twine, Susan M.; Shen, Hua; Sjostedt, Anders; Conlan, Wayne; Kaufmann, Gunnar F. (PLoS ONE, 2013)
Francisella tularensis subsp. tularensis is a highly virulent pathogen for humans especially if inhaled. Consequently, it is considered to be a potential biothreat agent. An experimental vaccine, F. tularensis live vaccine strain, derived from the less virulent subsp. holarctica, was developed more than 50 years ago, but remains unlicensed. Previously, we developed a novel live vaccine strain, by deleting the chaperonin clpB gene from F. tularensis subsp. tularensis strain, SCHU S4. SCHU S4ΔclpB was less virulent for mice than LVS and a more effective vaccine against respiratory challenge with wild type SCHU S4. In the current study, we were interested to determine whether a similar mutant on the less virulent subsp. holarctica background would also outperform LVS in terms of safety and efficacy. To this end, clpB was deleted from clinical holarctica strain, FSC200. FSC200ΔclpB had a significantly higher intranasal LD50 than LVS for BALB/c mice, but replicated to higher numbers at foci of infection after dermal inoculation. Moreover, FSC200ΔclpB killed SCID mice more rapidly than LVS. However, dermal vaccination of BALB/c mice with the former versus the latter induced greater protection against respiratory challenge with SCHU S4. This increased efficacy was associated with enhanced production of pulmonary IL-17 after SCHU S4 challenge.
Keywords: Francisella tularensis; Vaccines; Mouse models; Respiratory infections; Cytokines; Chaperone proteins; Chemokines; Vaccination and immunization

A physicist's view of matter and mind - Dharma-Wardana, Chandre (World Scientific Publishing, 2013)
This is a highly interdisciplinary book straddling physics and complex systems such as living organisms. The presentation is from the perspective of physics, in a manner accessible to those interested in scientific knowledge integrated within its socio-cultural and philosophical backgrounds. Two key areas of human understanding, namely physics and conscious complex systems, are presented in simple language. An optional technical presentation is also given in parallel where it is needed.

2013 OIC Manufacturing Problem Contest - Li, Li; Dobrowolski, George (Optical Interference Coatings, 2013)
A transmission filter from 400nm to 1100nm is selected for the contest to display current thin film manufacturing capabilities. Filters submitted by participants will be evaluated and the results will be presented at the conference.

Herschel view of the Taurus B211/3 filament and striations: evidence of filamentary growth? - Palmeirim, P.; André, Ph.; Kirk, J.; Ward-Thompson, D.; Arzoumanian, D.; Könyves, V.; Didelon, P.; Schneider, N.; Benedettini, M.; Bontemps, S.; Di Francesco, J.; Elia, D.; et al. (Astronomy & Astrophysics, 2013)
We present first results from the Herschel Gould Belt survey for the B211/L1495 region in the Taurus molecular cloud. Thanks to their high sensitivity and dynamic range, the Herschel images reveal the structure of the dense, star-forming filament B211 with unprecedented detail, along with the presence of striations perpendicular to the filament and generally oriented along the magnetic field direction as traced by optical polarization vectors. Based on the column density and dust temperature maps derived from the Herschel data, we find that the radial density profile of the B211 filament approaches power-law behavior, ρ ∝ r⁻².⁰± ⁰.⁴, at large radii and that the temperature profile exhibits a marked drop at small radii. The observed density and temperature profiles of the B211 filament are in good agreement with a theoretical model of a cylindrical filament undergoing gravitational contraction with a polytropic equation of state: P ∝ ργ and T ∝ ργ⁻¹, with γ = 0.97 ± 0.01 < 1 (i.e., not strictly isothermal). The morphology of the column density map, where some of the perpendicular striations are apparently connected to the B211 filament, further suggests that the material may be accreting along the striations onto the main filament. The typical velocities expected for the infalling material in this picture are ~0.5–1 km s⁻¹, which are consistent with the existing kinematical constraints from previous CO observations.
Keywords: Star formation; ISM individual objects; B211–ISM clouds; ISM structure

On some aspects of the wheel/rail interaction - Magel, Eric E.; Liu, Yan (Wear, 2013)
Problems in tribology and contact mechanics are becoming increasingly amenable to solution through models and simulation. But in application to the wheel/rail contact, there remain a number of very important features for which either gross simplifications or a lack of understanding or ability severely limits the success of those efforts. Examples include models of friction and material response (including damage functions). This paper examines a rather eclectic mix of wheel/rail factors with the goal of encouraging researchers to begin tackling and eradicating some of the bigger problem areas that remain in wheel–rail interaction modeling and to consider more rigorous implementation of real world conditions in simulations.
Keywords: Wheel–rail interaction; Rolling contact fatigue; Surface roughness; Pummeling; Conformality

Current knowledge on biotin nutrition in fish and research perspectives - Yossa, Rodrigue; Sarker, Pallab K.; Mock, Donald M.; Lall, Santosh P.; Vandenberg, Grant W. (Reviews in Aquaculture, 2013)
Biotin, a water-soluble vitamin, is essential for normal growth, development and health of all animals. In terrestrial animal nutrition, biotin has recently spurred scientific interest because of the increasing body of knowledge on biotin involvement in gene expression, cell cycle and reproduction in mammals, and recent advances in molecular biology techniques allowing a more effective estimation of biotin effects in metabolism and physiology. In contrast, this information is scarce in aquatic animal nutrition, as studies have essentially focused on the estimation of minimum biotin requirement for maximum growth and tissue storage as well as for the formulation of least-cost diet. This scarcity of information is also due to the lack of well-established indicators of biotin status in aquatic organisms. The present review is a comparative analysis of current knowledge on biotin physiology and nutritional biochemistry in terrestrial and aquatic animal nutrition. Also, general information on biotin sources, bioavailability, deficiency and requirement in mammals and fish is provided in order to plan further studies. In the future, biotin nutrition studies in aquaculture should also include haematological parameters, histopathology of the gills, liver and kidney, gonad development, gamete quality and quantity, fecundity, larvae survival and gene expression. Dietary biotin requirement levels should be estimated at every life history stage of farmed fish. The potential contribution of intestinal microflora to biotin supply in different fish species should be investigated. All this information will allow a better understanding of the essentiality of biotin in fish growth, development, reproduction and health.
Keywords: Aquatic animals; Biotin; Fish; Nutrition; Vitamin

Attosecond science - Corkum, P. B. (Attosecond Physics: Attosecond Measurements and Control of Physical Systems, 2013)
Attosecond technology builds on, and contributes to, important historic directions in science. For this reason, the science has the depth to yield important discoveries for a long time. Unfortunately the title "attosecond" science biases us to think mostly about dynamics but many of the most important applications of "attosecond technology" may not be related to dynamics at all. This broad set of applications point to the future impact of the technology.

Attosecond science and technology - Corkum, P.B. (2013 Conference on Lasers and Electro-Optics Europe and International Quantum Electronics Conference, CLEO/Europe-IQEC 2013, 2013)
An intense light pulse can extract an electron wave packet from an atom near a field crest. This wave packet responds to the field, gaining and losing momentum as the field oscillates. During the process portions of the wave packet are inevitably driven back to the ion, and recombining with substantial momentum and thereby transferring the wave packet characteristics into a broad bandwidth burst of radiation that can extend continuously from the ultraviolet to the soft X-rays. Many characteristics of attosecond pulse are imposed by the time-dependent-field of a light pulse. By controlling the time-dependent-field, we control attosecond pulse generation. © 2013 IEEE.
Keywords: Light; Light transmission; Quantum electronics; Wave packets; Attosecond pulse; Attosecond pulse generation; Attosecond science; Broad bandwidths; Electron wave packet; Intense light pulse; Light pulse; Soft X-ray; Electron optics

Femtosecond laser desorption of thin polymer films from a dielectric surface - Mercadier, L.; Peng, J.; Sultan, Y.; Davis, T.; Rayner, D.M.; Corkum, P.B. (MATEC Web of Conferences, 2013)
We desorb polymer films from fused silica with a femtosecond laser and characterize the results by atomic force microscopy. Our study as a function of beam geometry and energy reveals two ways of achieving spatially controlled nanodesorption. © Owned by the authors, published by EDP Sciences, 2013.
Keywords: Atomic force microscopy; Polymer films; Semiconducting films; Ultrashort pulses; Beam geometry; Dielectric surface; Thin polymer films; Two ways; Ultrafast lasers

Studying the electronic structure of molecules with high harmonic spectroscopy - Villeneuve, D. M.; Bertrand, J. B.; Corkum, P. B.; Dudovich, N.; Itatani, J.; Kieffer, J. C.; Légaré, F.; Levesque, J.; Mairesse, Y.; Niikura, H.; Schmidt, B. E.; Shiner, A. D.; et al. (Attosecond physics : attosecond measurements and control of physical systems, 2013)
High harmonic spectroscopy is a tool to study the valence electronic structure of atoms and molecules. It uses the techniques of high harmonic generation, in which a femtosecond laser ionizes the gas sample and XUV radiation is emitted in the forward direction. The XUV intensity, phase and polarization contain information about the orbital from which an electron was removed by the laser. High harmonic spectroscopy reveals details of electron-electron interactions, motion of electronic wave packets, and can follow a chemical reaction. © Springer-Verlag Berlin Heidelberg 2013.

Carrier envelope phase effects in strong field ionization of xenon with few-cycle 1.8 μm laser pulses - Schmidt, B.E.; Möller, M.; Sayler, A.M.; Shiner, A.D.; Vampa, G.; Légaré, F.; Villeneuve, D.M.; Paulus, G.G.; Corkum, P.B. (EPJ Web of Conferences, 2013)
Interferometrically CEP controlled few-cycle IR pulses revealed a strong influence on both, directly ionized and rescattered electrons in xenon for pulse durations from 2 to 5 cycles. © Owned by the authors, published by EDP Sciences, 2013.

Attosecond spatial control of ionizing electron wave packets - Zhang, L.; Xie, X.; Roither, S.; Kartashov, D.; Schoffler, M.; Shafir, D.; Corkum, P.B.; Baltuska, A.; Staudte, A.; Kitzler, M. (2013 Conference on Lasers and Electro-Optics Europe and International Quantum Electronics Conference, CLEO/Europe-IQEC 2013, 2013)
Angstrom and attosecond control of free electron wave packets is one of the pinnacles of attosecond science. Orthogonally polarized two-color (OTC) laser fields allow to control the motion of field-ionizing electronic wave packets both in time and space[1]. In OTC pulses time and space are connected and thus an attosecond time scale is established in the polarization plane for both the emitted and the re-colliding wave packets[2,3]. © 2013 IEEE.
Keywords: Quantum electronics; Wave packets; Attosecond science; Attosecond time scale; Electron wave packet; Electronic wave packets; Free electron; Laser fields; Polarization planes; Spatial control; Electron optics

Robotic operation of the DAO 1.2-m telescope and McKellar spectrograph - Monin, D.; Saddlemyer, L.; Bohlender, D. (Revista Mexicana de Astronomia y Astrofisica: Serie de Conferencias, 2013)
The DAO 1.2-m telescope has been successfully used to obtain astronomical spectra in unattended robotic mode for a decade and approximately 2/3 of the nights scheduled on the telescope are now used in this fashion. The availability of such robotic operation has boosted the telescope's subscription rate by approximately 50% since telescope users no longer have to travel to the DAO in order to conduct their observing programs. An overview of the robotic system and some details of its operation are presented.
Keywords: Instrumentation: spectrographs; Telescopes

Characteristics of electron beam welded CA6NM - Sarafan, Sheida; Wanjara, Priti; Champliaud, Henri; Mathieu, Louis; Lanteigne, Jacques (Proceedings of Materials Science and Technology, 2013)
In this study, the viability of thick-gauge section assembly for hydroelectric turbine manufacture was considered by electron beam welding CA6NM martensitic stainless steel, a widely utilized hydro-turbine cast material. Particularly, bead-on-plate trials on 60 mm-thick CA6NM plates were carried out using a 42 kW high vacuum electron beam welding system. The influence of the heat input, beam position, beam oscillation (XSF-YSF), and in-situ pre-heating conditions on the characteristics of the weldments, such as the bead geometry, weld integrity, fusion zone and HAZ microstructures and hardness were evaluated. A relationship between the welding parameters and the resulting depth of penetration was established. A methodology for in-situ heating of the thick-gauge section prior to welding was developed and evaluated for reducing welding defects in CA6NM.
A CD-only volume

Fiber Laser Deposition of INCONEL 718 Using Powders - Zhang, Yinan; Cao, Xinjin; Wanjara, Priti; Medraj, Mamoun (Proceedings of Materials Science and Technology, 2013)
Additive manufacturing is an emerging manufacturing and remanufacturing (repair) technique for value-added materials such as Inconel 718, particularly using a laser beam as the heating source. In this research work additive manufacturing of Inconel 718 using a continuous wave fiber laser and filler wire feed was studied. To simulate industrial conditions, the deposits were built on parent metal substrates that were extracted from an after-service Inconel 718 aerospace component. The evolution of the macrostructure, defects, microstructure and hardness of the deposits was evaluated in the as-deposited and post-clad heat treated conditions. The hardness of the laser deposits can be fully recovered to the level of the after-serviced parent metal after solution heat treatment and aging. The high integrity deposits had no visible pores but only some minor weld metal liquation cracking, which indicates the great potential of the laser deposition process to manufacture and repair superalloy components for aerospace applications.
A CD-only volume

Investigation of friction stir welding for industrial repair of commercially pure aluminum components - Larose, Simon; Wanjara, Priti; Monsarrat, Bruno; Comeau, Gail (Proceedings of Materials Science and Technology 2013, 2013)
Development of advanced repair technologies has gained increased interest recently stemming from the economic benefits of extending the service life of components. Instead of replacing the component, the failed regions can be refurbished by removing the damaged areas and repairing these with material addition and a suitable welding technology. Variations in material chemistry and dimensional mismatch at the interface between the original component and the added material constitute significant challenges for qualifying the repair process.Friction stir welding (FSW) was deliberated in this work to be the most promising solution for repairing flat commercially pure aluminum components. However, transfer of the FSW process from a laboratory scale to an industrial manufacturing environment has challenges specific to the nature of the application, which have been studied in this work alongside process development and optimization.

Effect of post-weld heat treatment on the mechanical properties of AA6061 friction stir welded joints - Wanjara, P.; Larose, S.; Gholipour, J.; Brochu, M. (Proceedings of Materials Science and Technology 2013, 2013)
Aluminum alloys are increasingly used as part of light-weighting strategies for manufacturing components in the transportation sector. Widespread application has, however, been limited by the low weldability of high strength aluminum alloys, such as crack sensitive grades of the 2XXX, 6XXX and 7XXX series. As a solid-state joining process, friction stir welding (FSW) presents a tremendous potential for assembling 6xxx series aluminum structures due to the low energy involved, which allows lower welding-induced distortions and improved mechanical performance of the joint. In this work, FSW of 3.18 mm thick AA6061-T6 sheets was investigated to examine the influence of weld pitch on the microstructure and mechanical performance of butt joints. The mechanical properties of the welds were found to be lower than those of the AA6061 in the T6 temper. A post-weld heat treatment was effective for bringing the mechanical properties close to the base metal values.

Monitoring wear and corrosion with integrated ultrasonic transducers - Kruger, S.E.; Wu, K.-T.; Blouin, A. (Journal of the Canadian Institute of Mining Metallurgy and Petroleum, 2013)
Real-time wear and corrosion measurement provides crucial information in determining an optimal schedule for corrective maintenance and is a powerful tool to maximize equipment availability and reliability. This paper presents integrated ultrasonic transducers (IUTs) that—when incorporated into structures to accurately measure the remaining thickness—can determine wear or corrosion losses. Transducers have a small footprint, perform comparable to other commercial ultrasonic transducers, and can withstand temperatures up to 400ºC. Results show that thickness changes of a few micrometres can be detected. Applications of this technology to mining equipment and its potential benefits are discussed.
Keywords: wear; corrosion; ultrasonic; permanent transducer; integrated ultrasonic trans

Anti-obesity efficacy and mechanism of a Chinese herbal formulation - Perry, Benjamin; Zhang, Junzeng; Saleh, Tarek; Wang, Yanwen (Canadian Journal of Diabetes, 2013)
Overweight and obesity have been increasing rapidly over the last couple of decades. It is estimated that by the year 2015, approximately 2.3 billion adults will be classified as overweight (body mass index, BMI (in kg/m2) > 27), at least 700 million of whom will be considered as obese (BMI > 30 kg/m2). As a result, obesity has been referred to by many as a 21st century epidemic. For the treatment and management of overweight and obesity, traditional Chinese medicine (TCM) and the use of herbal formulations has become an increasingly attractive form of alternative/complementary medicine. This trend is also occurring in the face of a weight-loss product market largely typified by mediocre long-term efficacy and safety concerns, and an increasing global desire to seek out and develop both safe and efficacious products from natural sources. An in vivo study using obese-prone rats treated by twice-daily oral gavage with total daily dosages of 500, 1500 or 3500 mg/kg BW of Liuwei Dihuang (LWDH) showed the body weight-lowering efficacy of this herbal formulation. Subsequent in vivo investigations using collected tissues and in vitro studies using relevant cells lines and a 95% ethanol extract of the herbal formulation explored two potential body weight-lowering mechanisms of action, including appetite suppression and enhanced fatty acid oxidation. The results demonstrate the potential of LWDH as a natural agent for the prevention/ management of body weight and highlight its potential.
Keywords: traditional Chinese medicine; anti-obesity efficacy; Liuwei Dihuang

CFHTLenS: the Canada–France–Hawaii Telescope Lensing Survey – imaging data and catalogue products - Erben, T.; Hildebrandt, H.; Miller, L.; van Waerbeke, L.; Heymans, C.; Hoekstra, H.; Kitching, T.D.; Mellier, Y.; Benjamin, J.; Blake, C.; Bonnett, C.; Cordes, O.; et al. (Monthly Notices of the Royal Astronomical Society, 2013)
We present data products from the Canada–France–Hawaii Telescope Lensing Survey (CFHTLenS). CFHTLenS is based on the Wide component of the Canada–France–Hawaii Telescope Legacy Survey (CFHTLS). It encompasses 154 deg2 of deep, optical, high-quality, sub-arcsecond imaging data in the five optical filters u*g′r′i′z′. The scientific aims of the CFHTLenS team are weak gravitational lensing studies supported by photometric redshift estimates for the galaxies. This paper presents our data processing of the complete CFHTLenS data set. We were able to obtain a data set with very good image quality and high-quality astrometric and photometric calibration. Our external astrometric accuracy is between 60 and 70 mas with respect to Sloan Digital Sky Survey (SDSS) data, and the internal alignment in all filters is around 30 mas. Our average photometric calibration shows a dispersion of the order of 0.01–0.03 mag for g′r′i′z′ and about 0.04 mag for u* with respect to SDSS sources down to iSDSS ≤ 21. We demonstrate in accompanying papers that our data meet necessary requirements to fully exploit the survey for weak gravitational lensing analyses in connection with photometric redshift studies. In the spirit of the CFHTLS, all our data products are released to the astronomical community via the Canadian Astronomy Data Centre at http://www.cadc-ccda.hia-iha.nrc-cnrc.gc.ca/community/CFHTLens/query.html. We give a description and how-to manuals of the public products which include image pixel data, source catalogues with photometric redshift estimates and all relevant quantities to perform weak lensing studies.
Keywords: CFHTLenS; Canada–France–Hawaii Telescope; data analysis

A suggested classification for two groups of Campylobacter myoviruses - Javed, Muhammad Afzal; Ackermann, Hans-Wolfgang; Azeredo, Joana; Carvalho, Carla M.; Connerton, Ian; Evoy, Stephane; Hammerl, Jens André; Hertwig, Stefan; Lavigne, Rob; Singh, Amit; Szymanski, Christine M.; Timms, Andrew; et al. (Archives of Virology, 2013)
Most Campylobacter bacteriophages isolated to date have long contractile tails and belong to the family Myoviridae. Based on their morphology, genome size and endonuclease restriction profile, Campylobacter phages were originally divided into three groups. The recent genome sequencing of seven virulent campylophages reveal further details of the relationships between these phages at the genome organization level. This article details the morphological and genomic features among the campylophages, investigates their taxonomic position, and proposes the creation of two new genera, the "Cp220likevirus and "Cp8unalikevirus" within a proposed subfamily, the "Eucampyvirinae"
Keywords: Myoviridae; virus protein; bacteriophage; Campylobacter; genetics; genome size; isolation and purification; molecular genetics; phylogeny; ultrastructure; virology; virus genome; Genome, Viral; Molecular Sequence Data; Viral Proteins

Molecular modeling of hydronium ion and water distribution in water-filled Pt nanochannels with corrugated walls - Nouri-Khorasani, Amin; Malek, Kourosh; Eikerling, Michael (Electrocatalysis, 2013)
Classical molecular dynamics was employed to study the impact of nanoconfinement and surface nanostructure on electrostatic phenomena and transport properties in catalyst layer pores of polymer electrolyte fuel cells. The porous structure of an ionomer-free ultrathin catalyst layer was represented by a water-filled nanochannel with corrugated and negatively charged Pt walls. The equilibrium hydronium ion distribution in the channel was used to assess local reaction conditions. We rationalized the effects of nanostructuring and metal surface charge on the electrostatic effectiveness factor of the channel. Furthermore, we investigated the water dynamics in the nanochannel, calculating the self-diffusion coefficients of surface and bulk-like water.
Keywords: Polymer electrolyte fuel cells; Molecular modeling; Electrostatic effects; Local reaction conditions; Catalyst layer effectiveness

Efficient algorithm for crack detection in sewer images from closed-circuit television inspections - Halfawy, Mahmoud R.; Hengmeechai, Jantira (Journal of Infrastructure Systems, 2013)
This paper presents a new algorithm for automated crack detection in sewer inspection closed-circuit television (CCTV) images. Cracks often have a long and thin rectangular shape with a darker appearance relative to other components in the image therefore, they typically manifest as edges. The proposed algorithm exploits previous information on the visual characteristics of crack features in typical CCTVimages to efficiently identify actual cracks and filter out background noise. The algorithm consists of three main steps. The first preprocessing step prepares the CCTV image for crack detection by identifying a set of candidate crack fragments using the Sobel method to detect horizontal and vertical edges separately. The Hough transform is then used to identify and remove the edges associated with information labels typically found in CCTV images. The second step applies a set of morphological operations to enhance candidate crack segments by filling the gaps between closely adjacent and aligned edges. The enhancement step results in merging crack fragments that potentially represent segments of the same crack curve. In the third step, two filters are defined based on previous knowledge of the visual characteristics of cracks, and then applied to remove noise edges and extract a set of real crack segments.We tested the proposed algorithm on a set of CCTV videos obtained from the cities of Regina and Calgary in Canada. The experimental results demonstrated the efficiency of the proposed algorithm, and showed its robustness in detecting various patterns of sewer cracks.
Keywords: Computer vision; Cracks; Defects; Feature extraction; Hough transforms; Image understanding; Mathematical morphology; Sewers; Automated defect detection; Background noise; Morphological operations; Pre-processing step; Rectangular shapes; Sewer inspection; Television inspection; Vertical edges; Crack detection; algorithm; computer vision; television; Alberta; Calgary; Regina; Saskatchewan

Blood-brain barrier transport of amyloid beta peptides in efflux pump knock-out animals evaluated by in vivo optical imaging - Zhang, Wandong; Xiong, Huaqi; Callaghan, Debbie; Liu, Hong; Jones, Aimee; Pei, Ke; Fatehi, Dorthy; Brunette, Eric; Stanimirovic, Danica (Fluids and barriers of the CNS, 2013)
Aβ transport (flux) across the blood-brain barrier (BBB) is thought to contribute to the pathogenesis of Alzheimer’s disease as well as to elimination of toxic amyloid from the brain by immunotherapy. Several BBB transporters have been implicated in Aβ exchange between brain parenchyma and the circulation, including efflux transporters P-glycoprotein/ABCB1 and BCRP/ABCG2. Here we describe an application of in vivo optical imaging methods to study Aβ transport across the BBB in wild-type or animals deficient in specific efflux transporters.
Keywords: Alzheimer’s disease; Aβ peptides; Blood-brain barrier; Mdr-1a/b P-glycoprotein; Abcb1a/b; Abcg2; Optical imaging

Altitude scaling of ice crystal accretion - Currie, T.C.; Fuleki, D.; Knezevici, D.C.; MacLeod, J.D. (5th AIAA Atmospheric and Space Environments Conference, 2013)
This paper describes experiments performed in an altitude chamber at the National Research Council of Canada (NRC) as the first step towards developing altitude scaling laws and procedures that will possibly allow aero-engines to be certified for operation in ice crystal clouds at high altitude by testing in sea level facilities. The principal objective was to test the hypothesis that accretion within a compressor due to ice crystal ingestion occurs when the local ratio of freestream liquid water content (LWC) to total water content (TWC) lies within a critical range at an accretion-susceptible location. If this hypothesis is correct, the local LWC/TWC ratio is the key parameter that must be matched in tests at low and high pressures to match accretions. Experiments were conducted in a small wind tunnel with an axisymmetric test article, consisting of a hemispherical nose attached to a conical afterbody, at a fixed TWC over a range of LWC/TWC ratios at (absolute) pressures of 34.5 kPa and 69 kPa to test the hypothesis. The LWC/TWC ratio was varied by changing the wet bulb temperature. Accretion steady-state volumes and growth rates measured at the two pressures were compared at conditions which were analytically predicted to produce matched LWC/TWC ratios. Good agreement was achieved in all cases. Accretion growth was greatest for LWC/TWC ratios in the range 10-25%. Additional tests demonstrated that wet bulb temperature, which was identified as an important variable in earlier studies, had little influence on accretion growth beyond its effect on LWC/TWC (i.e. ice particle melting). Tests were also conducted to determine whether accretion growth scales linearly with TWC at constant LWC/TWC. Those tests confirmed that not only does the accretion growth rate in the early growth phase scale in direct proportion to TWC, but so does the final size of the accretion. A simple semi-empirical model for predicting this behavior is described. While most of the tests were conducted with an ice particle median volumetric diameter of 45μ, some of the scaling tests were repeated with larger particles, which produced smaller accretions. © 2013 by Her Majesty the Queen in Right of Canada. Published by the American Institute of Aeronautics and Astronautics.
Keywords: Ice crystal clouds; Ice particles; Liquid water content; National Research Council of Canada; Semi-empirical modeling; Total water content; Volumetric diameters; Wet bulb temperature; Experiments; Sea level; Testing; Wind tunnels; Ice

Particle size effects on ice crystal accretion - Part II - Knezevici, D.C.; Fuleki, D.; Currie, T.C.; Galeote, B.; Chalmers, J.; MacLeod, J. (5th AIAA Atmospheric and Space Environments Conference, 2013)
This paper describes ongoing research intended to simulate ice accretion in an inter-compressor duct bleed slot resulting from the ingestion of altitude ice crystals. The authors have previously shown that ice crystal particle size plays an important role in the ice crystal accretion phenomenon. It was also shown that ice crystal particle size affects the degree of natural melt that occurs for a given aerodynamic condition. The data presented herein decouples the effects of ice particle melt and particle size distribution to generate accretions with the same ratio of freestream liquid-to-total water fraction. The effects of wet bulb temperature and ice particle size on the natural melting of ice crystals are discussed. An ice preservation procedure is followed to allow tracings of the accretion to be taken along the test article. Ice crystal particle size distribution is characterized using a shadowgraphy imaging technique. Finally, the reduction in accretion rate relative to the theoretical maximum rate of surface accretion by ice crystal particles is discussed. The test article simulates a forward facing, inclined endwall bleed slot in a gas turbine compressor as a simplified two-dimensional representation. The geometry, having a surface inclined 20° to the incoming flow, proved to be susceptible to mixed phase ice crystal accretion. Particle size and particularly the large particle tail of the distribution had a significant impact on the magnitude of accretion under mixed phase test conditions for wet bulb temperatures above and below 0°C. The leading edge growth rates were found to be 1/4 to 1/9 of the theoretical growth rate suggesting that erosion, splashing, particle bounce and other loss mechanism rates are significant. The ice tracings were used to estimate an accretion mass for a hypothetical large bypass ratio gas turbine. It was found that approximately 4kg of ice could be generated should the inter-compressor duct be exposed to the conditions tested for 5 minutes. © 2013 by Her Majesty the Queen in Right of Canada. Published by the American Institute of Aeronautics and Astronautics.
Keywords: Accretion rate; Gas turbine compressors; Incoming flows; Large particles; Loss mechanisms; Particle size effect; Water fraction; Wet bulb temperature; Compressors; Ducts; Gas turbines; Imaging techniques; Particle size; Particle size analysis; Ice

Micromilled optical elements for edge-lit illumination panels - Ronny, Rahima Afrose; Knopf, George K.; Bordatchev, Evgueni; Nikumb, Suwas (Journal of Micro/Nanolithography, MEMS, and MOEMS, 2013)
Edge-lit light guide panels (LGPs) with micropatterned surfaces represent a new technology for developing small- and medium-sized illumination sources for application such as automotive, residential lighting, and advertising displays. The shape, density, and spatial distribution of the micro-optical structures (MOSs) imprinted on the transparent LGP must be selected to achieve high brightness and uniform luminance over the active surface. We examine how round-tip cylindrical MOSs fabricated by precision micromilling can be used to create patterned surfaces on low-cost transparent polymethyl-methacrylate substrates for high-intensity illumination applications. The impact of varying the number, pitch, spatial distribution, and depth of the optical microstructures on lighting performance is initially investigated using LightTools™ simulation software. To illustrate the microfabrication process, several 100×100×6 mm3 LGP prototypes are constructed and tested. The prototypes include an “optimized” array of MOSs that exhibit near-uniform illumination (approximately 89%) across its active light-emitting surface. Although the average illumination was 7.3% less than the value predicted from numerical simulation, it demonstrates how LGPs can be created using micromilling operations. Customized MOS arrays with a bright rectangular pattern near the center of the panel and a sequence of MOSs that illuminate a predefined logo are also presented.
Keywords: optical light guide panels; edge lighting; micro-optics; micromilling

Development of an inverse method for material characterization - Saboori, M.; Champliaud, H.; Gholipour, J.; Gakwaya, A.; Savoie, J.; Wanjara, P. (Proceedings of Advances in Hydroelectric Turbine Manufacturing and Repair, 2013)
Conventional engineering analysis involves the determination of material properties under uniaxial loading conditions. The true stress-true strain curves generated through this way have been used in finite element modeling (FEM) of various forming processes. However, this method is only valid up to the onset of necking; after this point the stress state is not uniaxial and the errors between FEM results and experimental data are significant. In this paper a new work hardening equation for predicting material behavior after the instability was used for stainless steel 321 (SS 321) and Inconel 718 IN 718). A finite element model based on an inverse method was devised with the aim of determining the properties of isotropic materials after instability. To facilitate the process of material characterization, an algorithm was developed using LS-DYNA and Matlab software. Verification of this methodology was carried out by comparing the experimental load-displacement data (obtained by tensile testing) with the simulation results.
A CD-only volume
Keywords: inverse method; finite-element simulation; material properties

Quebec Safety Code, Chapter VIII – Building, and National Fire Code of Canada 2010 (amended) - National Research Council of Canada and Régie du bâtiment du Québec (National Fire Code of Canada, 2013)
This document, published by NRC in collaboration with the Régie du bâtiment du Québec, includes the amendments to Chapter VIII, Building, of the Quebec Safety Code, as well as an amended National Fire Code of Canada 2010 (NFC). Its contents include more stringent Quebec-specific provisions to improve fire safety in sleeping rooms and care occupancies, as well as provisions regarding the inspection and maintenance of building façades, multi-storey garages and water-cooling towers. The amended NFC clearly indicates the changes adopted by Quebec, which apply to the construction and renovation of buildings in that province. As in the case of the NFC, an objective-based approach was used to prepare Chapter VII, Building. The majority of the Code provisions are linked to objectives that describe the overall goals that the provisions are intended to achieve and to functional statements that describe conditions that help satisfy the objectives. This new information allows for flexibility by helping users evaluate alternative solutions to acceptable solutions described in the Code.
Keywords: Codes and guides

Simulations of magnetic field gradients due to micro-magnets on a triple quantum dot circuit - Poulin-Lamarre, G.; Bureau-Oxton, C.; Kam, A.; Zawadzki, P.; Studenikin, S.; Aers, G.; Pioro-Ladrière, M.; Sachrajda, A.S. (THE PHYSICS OF SEMICONDUCTORS: Proceedings of the 31st International Conference on the Physics of Semiconductors (ICPS) 2012, 2013)
To quantify the effects of local magnetic fields on triple quantum dots, the Heisenberg Hamiltonian has been diagonalized for three electrons coupled via the exchange interaction. In particular, we have investigated different geometries of micro-magnets located on top of the triple dot in order to optimize the field gradient characteristics. In this paper, we focus on two geometries which are candidates for an addressable EDSR triple quantum dot device. © 2013 AIP Publishing LLC.
Keywords: Magnetic fields; Magnets; Different geometry; EDSR; Field gradient; Heisenberg; Local magnetic field; Magnetic field gradient; Micro-magnets; Triple quantum; Semiconductor quantum dots

Enhanced charge detection: Amplification factor, phase reversal and measurement time dependence - Thorgrimson, J.; Studenikin, S.A.; Aers, G.C.; Kam, A.; Zawadzki, P.; Wasilewski, Z.R.; Bogan, A.; Sachrajda, A.S. (THE PHYSICS OF SEMICONDUCTORS: Proceedings of the 31st International Conference on the Physics of Semiconductors (ICPS) 2012, 2013)
Studenikin et al.[1] recently demonstrated a significant enhancement of the fringe contrast of coherent Landau-Zener-Stückelberg (LZS) oscillations between singlet S and triplet T+ two-spin states using a modified charge detection technique called enhanced charge detection (ECD). In this paper we explain the amplitude phase reversal and confirm the magnitude of the effect is consistent with our calibrations. We also show that the enhancement cannot be explained by a T1 effect. © 2013 AIP Publishing LLC.
Keywords: Amplification factors; Charge detection; Fringe contrasts; Measurement time; Phase reversal; Spin-qubits; Semiconductor quantum dots

Coordinate metrology and the proposed E57.02 static pose determination standard - MacKinnon, David; Beraldin, Jean-Angelo; Hong, Tsai; Marvel, Jeremy (Journal of the CMSC, 2013)
We present the Proposed Standard ASTM E57.02 "Standard Test Method for Evaluating Static Pose Measurement Systems" (Work Item ASTM WK31638) and explain why it should be considered important by coordinate metrologists. The stated purpose of the standard is to provide metrics and procedures to evaluate how well a non-contact 3D imaging system is able to determine an object's pose relative to the 3D imaging system. Pose estimation is particularly important for 3D imaging systems that can be moved during the process of generating a digital surface model of a surface, such as arm-mounted 3D imaging systems. The quality of the digital surface model generated by merging multiple depth maps depends on how well the 3D imaging system, or systems, was able to determine their pose during acquisition. We provide a summary of the document to date, the proposed test methods, and the current status of the proposed standard.
Keywords: pose estimation; ASTM; E57; non-contact 3D imaging system; standard

Proposed E57.02 range measurement performance standard for medium-range 3D imaging systems - MacKinnon, David Kenneth; Cournoyer, Luc; Saidi, Kamel; Cheok, Geraldine; Bridges, Robert; Ingimarson, Darin (Journal of the CMSC, 2013)
In this article, we present the proposed standard ASTM E57.02 “Test Method to Evaluate the Range Measurement Performance of 3D Imaging Systems in the Medium Range” (Work Item ASTM WK12373). The stated purpose of the standard is to provide metrics and procedures to evaluate the range measurement performance of medium-range (2 m to 150 m working distance) noncontact three-dimensional (3D) imaging systems. We provide a summary of the document to date, the proposed test methods, and the current status of the proposed standard. As an example, we also present some preliminary results of experiments performed at the National Research Council Canada (NRCC).

On the quality of residential ventilation systems in Canada - MacDonald, Iain; Magee, R.; Fugler, D. (2013)
The residential ventilation market in Canada is defined by the country’s geography and its relationship with the USA. Codes and standards have been developed in Canada to unify the approach across the country and coordinate with the USA market, however due to regional variations (partially a result of the political structure) the “model” building code developed at the national level is implemented at the provincial/territorial level and can subsequently be modified at the municipal level. This can lead to regional variations in code requirements, e.g. the predominant use of exhaust-only systems in Ontario. The long heating season and cold winters have driven construction standards in Canada to produce air-tight buildings as a matter of course. The current energy code (2012) states that the worst case air change rate at 50 Pa for new build is 3.2 and if the air barrier system has been constructed to a higher standard (prescriptively defined) 2.5 air changes per hour, or the tested value can be used. Given these levels of air tightness were being achieved in the 1980’s it became apparent that deliberate mechanical ventilation was required. This need had been introduced into the building code 1980 but was refined and expanded through 1995 (the code is updated on a five year cycle). In 1991 the mechanical ventilation standard (CSA F-326-M91) was published covering design, installation and commissioning. The rate of new construction in Canada is such that almost 25% of single family homes have been constructed since 1990. Combining this with the code requirements for mechanical ventilation systems it can be concluded that the residential ventilation industry is well developed and mature. Future refinements will be made as our understanding of health and ventilation is further developed and as energy constraints become more pertinent.

Integrated rapid 3D mapping and laser additive repair of gas turbine engine components - Xue, Lijue; Donovan, Matt; Li, Yangsheng; Chen, Jianyin; Wang, Shaodong; Campbell, Glen (2013 ICALEO Conference Proceedings, 2013)
National Research Council Canada (NRC) has developed precision laser additive repair of worn gas turbine components. The repair system uses integrated 3D mapping and laser additive deposition. The integrated inspection and repair system is capable of inspecting and repairing a worn gas turbine injector in less than one hour. This innovative system dramatically improves repair time and cost of high value gas turbine components. In this paper, a case study will be presented as a joint effort by NRC and UTC Aerospace Systems to evaluate the feasibility of repair of worn fuel injectors from a land based gas turbine engine. The project evaluated the use of laser cladding of cobolt alloy L-605 for repair of worn engine components on a Rolls Royce 501K engine. Test results reveals that laser clad L-605 on wrought L-605 substrate demonstrates comparable or even substantially improved fatigue life as compared to the baseline L-605 specimens at elevated temperature. Laser clad L-605 also shows comparable wear resistance. The paper will demonstrate the improved repair of the fuel injectors via laser cladding repair and the metallurgical evaluation of the repair. The paper documents the improvement of the repair from several weeks and fabrication of several placement componenets to a matter of only a few hours to inspect and repair using the NRC laser additive manufacturing system.
On CD-ROM

5-axis in-line measurement system for laser materials processing - Li, Yangsheng; Xue, Lijue; Wang, Shaodong (ASME 2013 International Mechanical Engineering Congress and Exposition, Volume 2A: Advanced Manufacturing, 2013)
The dimensional and positional information is very important for laser materials processing of components, especially for laser cladding-based additive manufacturing. Therefore, inspection of the component based on its original CAD model is essential to ensure the component meeting the geometrical requirements. In general, the processed component has to be dismounted from the laser fabrication system before it can be inspected, which is time-consuming and may introduce alignment error from datum. In this paper, a 5-axis in-line measurement system is introduced, in which a non-contact laser measuring method along with CAD/CAM software is integrated to a laser materials processing system. An algorithm has been developed to automatically generate NC programs for measurement and comparison for outside features of components. Therefore, the inspection can be performed just after the component has been fabricated on the same system. Comparing to a 3-axis measuring system we reported before, the developed 5-axis inline measurement system provides much more flexibility, accessibility and accuracy for performing measurement on site. The developed in-line measuring capability can extend the functionality of conventional laser materials processing system and significantly shorten inspection time.

Methods and role of embryo rescue technique in alien gene transfer - Lulsdorf, Monika M.; Ferrie, Alison; Slater, Susan M. H.; Yuan, Hai Ying (Alien Gene Transfer in Crop Plants, Volume 1, 2013)
Embryo abortion occurs frequently in wide crosses, and thus embryo rescue is required for survival of the next generation. Rescues are performed by either directly transferring the excised embryo to an artificial medium or indirectly through flower (ovary), immature seed (fertilized ovule), or pod (silique) culture. Various techniques used for oil crops, cereals, legumes, and horticultural crops are presented. Altering medium components were the major routes for developing protocols for each species with adaptations to the base medium, sucrose concentration, or vitamin and growth regulator content. Monocot culture tended to be more direct than dicot culture, where many protocols required a multi-step approach from pod to ovule culture to embryo rescue, shoot regeneration, and root induction. Each step required a specific medium and growth conditions. Hybrid embryos as young as 2 days after pollination have been recovered. However, many species such as soybean and chickpea still need procedures for rescue of very young embryos. In other species hurdles such as poor rooting have been overcome by using grafting techniques. Embryo rescue remains a useful component in any breeding program where wide or interspecific crosses are preformed, where rapid cycling through generations is used, and where germplasm preservation is required.
Keywords: Embryo rescue; Protocols; Oil crops; Cereals; Legumes; Horticulture crops

A generic model of transcriptional regulatory networks : application to plants under abiotic stress - Tchagang, Alain B.; Phan, Sieu; Famili, Fazel; Pan, Youlian; Cutler, Adrian J.; Zou, Jitao (IEEE, 2013)
Understanding the relationships between transcription factors (TFs) and genes in plants under abiotic stress responses, tolerance and adaptation to adverse environments is very important in developing resilient crop varieties. While experimental methods to characterize stress responsive TFs and their targets are highly accurate, identification and characterization of the role of a given gene in a given stress response event are often laborious and time consuming. Computational approaches, on the other hand, offer a platform to identify new knowledge by integrating high throughput omics data and mathematical methods/models. In this research, we have developed a generic linear model of transcriptional regulatory networks (TRNs) and a companion algorithm to identify and to characterize stress responsive genes and their roles in a given stress response event. The proposed methodology was applied to plants, by using Arabidopsis thaliana as an example, under abiotic stress. Well known interactions were inferred as well as putative novel ones that may play important roles in plants under abiotic stress conditions as confirmed by statistical and literature evidences.
Keywords: Abiotic-stress response; Adverse environment; Arabidopsis thaliana; Computational approach; Experimental methods; Mathematical method; Stress-responsive gene; Transcriptional regulatory networks

Conductivity control of as-grown branched indium tin oxide nanowire networks - LaForge, J. M.; Cocker, T. L.; Beaudry, A. L.; Cui, K.; Tucker, R. T.; Taschuk, M. T.; Hegmann, F. A.; Brett, M. J. (Nanotechnology, 2013)
Branched indium tin oxide (ITO) nanowire networks are promising candidates for transparent conductive oxide applications, such as optoelectronic electrodes, due to their high porosity. However, these branched networks also present new challenges in assessing conductivity. Conventional four-point probe techniques cannot separate the effect of porosity on the long-range conductivity from the intrinsic material conductivity. Here we compare the average nanoscale conductivity within the film measured by terahertz time-domain spectroscopy (THz-TDS) to the film conductivity measured by four-point probe in a branched ITO nanowire network. Both techniques report conductivity increases with deposition flux rate from 0.5 to 3.0 nm s-1, achieving a maximum of ∼10 (Ω cm)-1. Modeling the THz-TDS conductivity data using the Drude-Smith model allows us to distinguish between conductivity increases resulting from morphological changes and those resulting from the intrinsic properties of the ITO. In particular, the intrinsic material conductivity within the nanowires can be extracted, and is found to reach a maximum of ∼3000 (Ω cm)-1, comparable to bulk ITO. To determine the mechanism responsible for increasing conductivity with flux rate, we characterize dopant concentration and morphological changes (i.e., to branching behavior, nanowire diameter and nucleation layers). We propose that changes in the electron density, primarily due to changes in O-vacancy concentration at different flux rates, are responsible for the observed conductivity increase. This understanding will assist balancing structural and conductivity requirements in applications of transparent conductive oxide networks.
Keywords: branched nanowires; nanowires; indium tin oxide; Hz time-domain spectroscopy; conductivity

Spatially resolved LMC star formation history - I. Outside in evolution of the outer LMC disc - Meschin, I.; Gallart, C.; Aparicio, A.; Hidalgo, S. L.; Monelli, M.; Stetson, P. B.; Carrera, R. (Monthly Notices of the Royal Astronomical Society, 2013)
We study the evolution of three fields in the outer Large Magellanic Cloud (LMC) disc (Rgc = 3.5-6.2 kpc). Their star formation history indicates a stellar population gradient such that younger stellar populations are more centrally concentrated. We identify two main starforming epochs, separated by a period of lower activity between ≃7 and ≃4Gyr ago. Their relative importance varies from a similar amount of stars formed in the two epochs in the innermost field to only 40 per cent of the stars formed in the more recent epoch in the outermost field. The young star-forming epoch continues to the present time in the innermost field, but lasted only till ≃ 0.8 and 1.3Gyr ago at Rgc = 5°.5 and 7°.1, respectively. This gradient is correlated with the measured HI column density and implies an outside-in quenching of the star formation, possibly related to a variation of the size of the HI disc. This could either result from gas depletion due to star formation or ram-pressure stripping, or from to the compression of the gas disc as ram pressure from the MilkyWay halo acted on the LMCinterstellarmedium. The latter two situations may have occurred when the LMC first approached the Milky Way.
Keywords: Hertzsprung–Russell and colour–magnitude diagram; galaxies: evolution; Magellanic Clouds; galaxies: stellar content; galaxies: structure

The Dominion astrophysical observatory magnetic field survey (DMFS) - Bohlender, David A.; Monin, Dmitry (Magnetic Fields throughout Stellar Evolution, 2013)
In this paper we present a few results from the first three years of an ongoing survey of globally-ordered magnetic fields in relatively faint (down to V ≈ 9) upper main sequence peculiar stars that we are conducting on the Dominion Astrophysical Observatory (DAO) Plaskett telescope. The DMFS uses the inexpensive DAO polarimeter module, dimaPol, mounted at the Cassegrain focus of the 1.8 m telescope to detect new magnetic stars and determine rotation periods and longitudinal magnetic field curves using medium-resolution (R ≈ 10,000) circular spectropolarimetry of both the Hβ line and metal lines in an approximately 280 Å wide wavelength region centered on Hβ. By concentrating on the mid-B to A-type peculiar stars, the DMFS provides an extension to the 'Magnetism in Massive Stars' (MIMES) Large Program which concentrated on similar field detections in more massive stars.
Keywords: magnetic fields; instrumentation: polarimeteres; stars: magnetic fields

A nuclear forensic method for determining the age of radioactive cobalt sources - Charbonneau, Luc; Benoit, Jean-Michel; Jovanovic, Slobodan; St-Amant, Nadereh; Kiser, Stephen; Cooke, Michael W.; Mercier, Jean-François; Nielsen, Kathy; Kelly, David; Samuleev, Pavel; Galea, Raphael; Moore, Kimberly; et al. (Analytical Methods, 2013)
An analytical procedure for determining the relative amounts of ⁶⁰Co and its ⁶⁰Ni daughter in a radioactive cobalt source by means of chromatographic separation and radiometric and mass spectrometric detection was developed, optimized and assessed through two round robin exercises for nuclear forensic investigations. Solid phase extraction (EXC) using Ni resin (Eichrom) and ion exchange (IEC) using Dowex-1X8 (Acros Organics) chromatographic approaches were considered for separating Co and Ni. Decontamination factors of 25 and 2.8 × 10&#8310 were measured for EXC and IEC, respectively. Based on those results, only the IEC option was pursued. The effects of particle size, mass of resin, and degree of cross-linkage for decontamination performance were assessed, and the loading/eluting conditions were optimized. Canadian (CNSC, RPB, UL, RMC, AECL) and American (ANL) laboratories participated in two round robin exercises designed by the National Research Council of Canada to determine the suitability and limitations of the proposed methods. Age determination for freshly irradiated sources (<1 a) and for sources with high Ni content was challenging for the laboratories. Nevertheless, age estimates were obtained with sufficient accuracy for nuclear forensic purposes.
Keywords: Analytical procedure; Chromatographic separations; Decontamination factors; Mass spectrometric detection; Nuclear forensics; Radioactive cobalt; Solid-phase extraction; Cobalt; Liquid chromatography; Nickel; Optimization; Radioactivity; Resins; Radiation decontamination

A mutant Brassica napus (canola) population for the identification of new genetic diversity via TILLING and next generation sequencing - Gilchrist, Erin J.; Sidebottom, Christine H. D.; Koh, Chu Shin; MacInnes, Tanya; Sharpe, Andrew G.; Haughn, George W. (PLoS One, 2013)
We have generated a Brassica napus (canola) population of 3,158 EMS-mutagenised lines and used TILLING to demonstrate that the population has a high enough mutation density that it will be useful for identification of mutations in genes of interest in this important crop species. TILLING is a reverse genetics technique that has been successfully used in many plant and animal species. Classical TILLING involves the generation of a mutagenised population, followed by screening of DNA samples using a mismatch-specific endonuclease that cleaves only those PCR products that carry a mutation. Polyacrylamide gel detection is then used to visualise the mutations in any gene of interest. We have used this TILLING technique to identify 432 unique mutations in 26 different genes in B. napus (canola cv. DH12075). This reflects a mutation density ranging from 1/56 kb to 1/308 kb (depending on the locus) with an average of 1/109 kb. We have also successfully verified the utility of next generation sequencing technology as a powerful approach for the identification of rare mutations in a population of plants, even in polyploid species such as B. napus. Most of the mutants we have identified are publically available.
Keywords: endonuclease; mesylic acid ethyl ester; plant DNA

An activated form of UFO alters leaf development and produces ectopic floral and inflorescence meristems - Risseeuw, Eddy; Venglat, Prakash; Xiang, Daoquan; Komendant, Kristina; Daskalchuk, Tim; Babic, Vivijan; Crosby, William; Datla, Raju (PLoS One, 2013)
Plants are unique in their ability to continuously produce new meristems and organ primordia. In Arabidopsis, the transcription factor LEAFY (LFY) functions as a master regulator of a gene network that is important for floral meristem and organ specification. UNUSUAL FLORAL ORGANS (UFO) is a co-activator of LEAFY and is required for proper activation of APETALA3 in the floral meristem during the specification of stamens and petals. The ufo mutants display defects in other parts of the flower and the inflorescence, suggestive of additional roles. Here we show that the normal determinacy of the developing Arabidopsis leaves is affected by the expression of a gain-of-function UFO fusion protein with the VP16 transcriptional activator domain. In these lines, the rosette and cauline leaf primordia exhibit reiterated serration, and upon flowering produce ectopic meristems that develop into flowers, bract leaves and inflorescences. These striking phenotypes reveal that developing leaves maintain the competency to initiate flower and inflorescence programs. Furthermore, the gain-of-function phenotypes are dependent on LFY and the SEPALLATA (SEP) MADS-box transcription factors, indicative of their functional interactions with UFO. The findings of this study also suggest that UFO promotes the establishment of the lateral meristems and primordia in the peripheral zone of the apical and floral meristems by enhancing the activity of LFY. These novel phenotypes along with the mutant phenotypes of UFO orthologs in other plant species suggest a broader function for UFO in plants.

Generation of stable engineered chromosomes in soybean - Zhang, Yunfang; Itaya, Asuka; Fu, Ping; Zheng, Suqin; Hulm, Jacquie; Blahut-Beatty, Laureen; Marillia, Elizabeth-France; Lindenbaum, Michael; Fabijanski, Steven; Simmonds, Daina (Plant biotechnology, 2013)
A system for engineering plant chromosomes has been developed to facilitate the introduction of novel genes into the plant genome. The system is based on the establishment of a unique genetic locus within the ribosomal DNA (rDNA) region of the host chromosome to provide a permissive environment for expression of the introduced genes of interest (GOI). The genetic locus can exist within an independent, fully functional "minichromosome" (MC) or as a segment of a modified host chromosome (termed Engineered Trait Locus or ETL). The site-specific integration of transgenes to the rDNA locus isolates them from other endogenous genes, an advantage over conventional transformation in which foreign genes are inserted randomly into the host genome. Furthermore, MCs or ETLs can confer stability and high expression of the transgenes, as demonstrated in mammalian systems. To evaluate this system in plants, several MC and ETL lines have been generated in soybean, an important crop used worldwide for protein and oil consumption. The characterization of a soybean line containing an MC demonstrates that 1) the MC is stable over multiple generations as well as in field conditions, 2) maintaining the MC has no adverse phenotypic consequences, and 3) the MC can provide high-level expression of the introduced GOI.
Keywords: Engineered chromosomes; artificial chromosomes; traits; stacking; soybean; field trial

Guest editorial: 3D imaging, processing and modelling - Godin, Guy; Goesele, Michael; Matsushita, Yasuyuki; Sagawa, Ryusuke; Yang, Ruigang (International Journal of Computer Vision, 2013)

Survey of variable stability helicopter applications in handling qualities research - Fletcher, J.; Alexander, Marc; Hoefinger, Marc (69th American Helicopter Society International Annual Forum 2013 : Vertical Flight Technical Society, Phoenix, Arizona, USA, 21-23 May 2013., 2013)
Applications of Variable Stability Systems (VSS) rotorcraft are motivated by client requirements. Areas may include vehicle and technology development, concept demonstration, regulatory standards investigations, and training programs. A survey of civilian Canadian and European full-authority VSS rotorcraft (NRC Bell 205A Airborne Simulator, NRC Bell 412 Advanced Systems Research Aircraft, and DLR EC 135 Active Control Technology/Flying Helicopter Simulator) presents an overview of facilities, applications, operational challenges, and lessons learned. The breadth of scientific capability highlights the potential of these modern facilities to support development of next generation aeronautical and aerospace products. Copyright © 2013 by the American Helicopter Society International, Inc. All rights reserved.
Keywords: Active control technologies; Aerospace products; Client requirement; Concept demonstration; Operational challenges; Regulatory standards; Technology development; Variable stability systems; Bells; Helicopter rotors; Research aircraft; Rotors; Surveys; Helicopters

Substrate integrated waveguide couplers for tapered slot antennas in adaptive receiver applications - Locke, Lisa; Kordiboroujeni, Zamzam; Bornemann, Jens; Claude, Stéphane (2013 7th European Conference on Antennas and Propagation (EuCAP), 2013)
The design of substrate integrated waveguide couplers for adaptive receiver applications employing tapered slot antennas is presented. Two different 20 dB couplers are designed on low-permittivity substrate, and their performances are verified by commercially available field solvers. For an incident plane wave, the systems of antenna and couplers are demonstrated to provide the desired operation between 18 GHz and 28 GHz in terms of both received E-field levels and propagation through the components. Antenna radiation patterns are provided. Two different SIW coupler designs are compared with measurements and are found in good agreement, thus validating the design procedure. © 2013 EurAAP.
Keywords: Adaptive receivers; Coupler design; Design procedure; E-field; Plane wave; Tapered slot antennas; Antenna radiation; Design; Directional couplers; Microwave circuits; Slot antennas; Waveguide couplers; Substrate integrated waveguides

Near-field cavity optomechanical probing of nanomechanics - Hryciw, Aaron C.; Khanaliloo, Behzad; Wu, Marcelo; Healey, Chris J.; Barclay, Paul (CLEO: QELS_Fundamental Science, CLEO:QELS FS 2013, 2013)
An optical fiber taper placed in the near field of a "split-beam" photonic crystal nanobeam cavity with a physical gap at the cavity center breaks the system's vertical dielectric symmetry, enabling selective optomechanical coupling to multiple cantilever resonances using a single optical nanocavity mode. © 2013 Optical Society of America.

Optomechanical torsional sensing in photonic crystal split-beam nanocavities - Wu, Marcelo; Hryciw, Aaron C.; Freeman, Mark R.; Davis, John P.; Barclay, Paul E. (CLEO: Science and Innovations, CLEO_SI 2013, 2013)
Photonic crystal split-beam nanocavities are proposed and fabricated for optomechanical detection of torsional motion. Large optomechanical transduction around 20 GHz/nm allows for predicted torsional sensitivities down to 10-20 Nm=pHz. © 2013 Optical Society of America.
Keywords: Nano-cavities; Optomechanical; Torsional motion; Photonic crystals

Characterization of detector modulation-transfer function with noise, edge, and holographic methods - McLeod, Robert A.; Malac, Marek (Ultramicroscopy, 2013)
We developed a new method for characterization of detector performance used in the transmission electron microscope (TEM) based on the measured contrast of holographic fringes. The new method changes spatial frequency of the measured holographic fringes, generated by an electrostatic biprism and Schottky or cold field-emission gun, to sample the modulation-transfer function (MTF) of the detector. The MTF of a Gatan Ultrascan™ 1000 charged-coupled detector (CCD) is evaluated using the new method and the results are compared to the established noise and slanted-edge method results. Requirements for accuracy of the edge and noise MTF methods are discussed. We consider issues surrounding incomplete read-out and how it affects the gain reference normalization of the detector. We evaluate how the MTF affects optimization of experimental parameters in the TEM. © 2013 Elsevier B.V.
Keywords: Slow-scan CCD detector; CCD camera; Electron detection; Scintillator; Modulation transfer function (MTF); Point spread function (PSF); Noise transfer function (NTF); Noise power spectrum (NPS); Incomplete read-out; Detector quantum efficiency (DQE); Detector noise; Electron holography; Transmission electron microscopy (TEM); Gain reference; Reference images

Characterization of biopharmaceuticals by NMR spectroscopy - Wishart, David S. (TrAC - Trends in Analytical Chemistry, 2013)
Recent improvements in nuclear magnetic resonance (NMR) - automation, sensitivity, resolution, pulse-sequence design and spectral processing - are giving novel insights into a wide range of biotech drugs. Real-world applications and emerging trends in biopharmaceutical NMR are being used to help in discovery, design, and characterization of these drugs and to improve assessment of their efficacy, quality and similarity. © 2013 Elsevier Ltd.
Keywords: Biopharmaceuticals; Biosimilar; Characterization; Formulation; Nuclear magnetic resonance (NMR); Oligonucleotide; Peptide; Polysaccharide; Protein; Quality control

Spray coated high-conductivity PEDOT:PSS transparent electrodes for stretchable and mechanically-robust organic solar cells - Tait, Jeffrey G.; Worfolk, Brian J.; Maloney, Samuel A.; Hauger, Tate C.; Elias, Anastasia L.; Buriak, Jillian M.; Harris, Kenneth D. (Solar Energy Materials and Solar Cells, 2013)
High conductivity poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) was spray cast to form highly flexible transparent electrodes for forward- and inverted-mode organic solar cells (OSCs). A multiple solvent ink containing ethylene glycol was developed, and a post-deposition annealing step contributed to a high conductivity of 1070±50 S cm-¹. Sheet resistance and transmission at a wavelength of 550 nm were controlled within 24-259 Ω □-¹ and 71-95%, respectively, which are amongst the best-reported combined characteristics. Forward-mode OSCs with spray coated PEDOT:PSS anodes yielded a power conversion efficiency of 3.2%. Mechanical bending and stretching tests demonstrated that the flexibility of these PEDOT:PSS layers were far superior to that of ITO: elastic moduli were reduced by more than an order of magnitude, and the resistance increased far more slowly under both uniaxial stretching and bending to progressively smaller radii of curvature. With these experiments, the minimum radii of curvature and maximum uniaxial strains at which acceptable performance is maintained were investigated. Collectively, our results illustrate a promising future for the scalable printing of low-cost PEDOT:PSS-based flexible transparent electrodes. © 2012 Crown All rights reserved.
Keywords: ITO-free; PEDOT:PSS; Polymer Solar Cells; Spray coating; Stretchable electronics; Bending tests; Conversion efficiency; Electrodes; Ethylene glycol; Flexible electronics; Organic solvents; Solar cells; Conducting polymers

Tuning iron pyrite thin film microstructure by sulfurization of columnar iron precursors - LaForge, Joshua M.; Gyenes, Balazs; Xu, Sijia; Haynes, Landon K.; Titova, Lyubov V.; Hegmann, Frank A.; Brett, Michael J. (Solar Energy Materials and Solar Cells, 2013)
Iron pyrite is a promising material for photovoltaic power production due to low material extraction and processing costs and high optical absorption. Reliable production of photovoltaic grade iron pyrite thin films has, however, been challenging. One potential fabrication route is the direct conversion of iron-to-iron pyrite by sulfur annealing (sulfurization). Bulk iron thin films are used typically but they can suffer from cracking or delamination. Herein we report the sulfurization of porous, columnar Fe films deposited with Glancing Angle Deposition (GLAD), which allows us to control the inter-column spacing (void-fraction) of the precursor film. We show that the morphology and microstructure of the iron pyrite films are strongly affected by the void-fraction. By precisely tuning the void-fraction of the precursor film at 82 oblique angle incidence deposition we can produce iron pyrite films with increased crystallite sizes >100 nm with a uniform, crack-free, facetted granular microstructure. Large crystallites may reduce carrier recombination at grain boundaries, which is attractive for photovoltaic devices. Further increasing the void-fraction produces a columnar iron pyrite structure. We also report composition, electrical and optical characterization including a 27 ps lifetime of photocarriers measured with ultrafast optical-pump/THz-probe. Structured, porous precursors offer an alternate route to control microstructure and film stress during fabrication of iron pyrite thin films. © 2013 Elsevier B.V.
Keywords: Carrier recombination; Fabrication routes; Glancing Angle Deposition; Granular microstructure; Optical characterization; Photovoltaic devices; Photovoltaic power; Sulfurization; Cracks; Deposition; Electrooptical materials; Failure (mechanical); Grain boundaries; Microstructure; Photovoltaic cells; Pyrites; Semiconductor materials; Thin films; Void fraction; Iron

Selective room temperature nanostructured thin film alcohol sensor as a virtual sensor array - Beckers, N. A.; Taschuk, M. T.; Brett, M. J. (Sensors and Actuators, B: Chemical, 2013)
Nanostructured SiO2 thin films fabricated via glancing angle deposition on interdigitated electrodes were used as room temperature alcohol sensors. Both frequency dependent capacitance and impedance were used to analyze sensor response to methanol, ethanol, 1-propanol, 2-propanol, and 1-butanol. Sensor responsivity was examined across the entire percent vapour saturation range for the same set of alcohols and the detection limit for ethanol, as an example, was derived. The response and recovery times for ethanol were determined from a pulse test and the responsivity curves, giving values of 66 s and 76 s, respectively. Sensor lifetime was examined for the same set of alcohols with and without irradiation from a UV-LED. We observed that sensor aging for the detection of ethanol and 1-butanol was greatly reduced under irradiation from the UV-LED whereas the UV-LED had little effect on aging for methanol, 1-propanol and 2-propanol. Using the frequency dependent responsivity curves of our sensors, we developed an algorithm that enables a single sensor to distinguish between methanol, ethanol and 2-propanol in a blind protocol test. In five out of seven trials, the algorithm successfully identified both the alcohol and concentration thereby demonstrating room temperature single sensor selectivity. © 2012 Elsevier B.V. All rights reserved.
Keywords: Detection limits; Frequency dependent; Frequency-dependent capacitance; Glancing Angle Deposition; Inter-digitated electrodes; Nanostructured thin film; Saturation range; Virtual sensor; Algorithms; Chemical sensors; Deposition; Ethanol; Irradiation; Methanol; Propanol; Thin films; Vapor deposition

Quantitative magneto-mechanical detection and control of the Barkhausen effect - Burgess, J. A. J.; Fraser, A. E.; Fani Sani, F.; Vick, D.; Hauer, B. D.; Davis, J. P.; Freeman, M. R. (Science, 2013)
Quantitative characterization of intrinsic and artificial defects in ferromagnetic structures is critical to future magnetic storage based on vortices or domain walls moving through nanostructured devices. Using torsional magnetometry, we observe finite size modifications to the Barkhausen effect in the limiting case of a single vortex core interacting with individual pointlike pinning sites in a magnetic thin film. The Barkhausen effect in this limit becomes a quantitative two-dimensional nanoscale probe of local energetics in the film. Tailoring the pinning potential using single-point focused ion beam implantation demonstrates control of the effect and points the way to integrated magneto-mechanical devices incorporating quantum pinning effects.
Keywords: ferromagnetic material; magnetic nanoparticle; magnetic method; mechanical theory; quantitative analysis; quantum mechanics; torsion; Barkhausen effect; energy transfer; film; ion therapy; magnetism; magnetometry