Bernier M.,University LavalQuebec |
Fournier V.,University LavalQuebec |
Eccles L.,Technology Transfer Team
Canadian Entomologist | Year: 2015
The small hive beetle (SHB), Aethina tumida Murray (Coleoptera: Nitidulidae), is a non-native pest of honey bees (Apis mellifera Linnaeus (Hymenoptera: Apidae)) newly introduced to Canada. The effectiveness of three in-hive traps was tested in springtime in West-Montérégie (southern Québec, Canada) and in late summer in Essex County (southern Ontario, Canada): AJ's Beetle Eater™ (AJ's Beetle Eater), Beetle Barn™ (Rossmann Apiaries), and Hood™ trap (Brushy Mountain Bee Farm). Traps were placed in the brood chamber of 12 colonies in West-Montérégie, and in 48 colonies in the top honey super in Essex County. In-hive traps were effective in reducing SHB populations without compromising the bee population or colony weight gain. In West-Montérégie, the Beetle Barn™ was the most effective trap during the first week, when SHB populations were high. It was less effective when honey bees sealed trap openings with propolis. In Essex County, the AJ's Beetle Eater™ was the most effective throughout the trial. There was no difference in efficacy between the various solutions used in the Hood™ trap (mineral oil versus mineral oil and apple cider vinegar). © Entomological Society of Canada 2014.
Celso F.,Sudan University of Science and Technology |
Mikhailenko S.D.,Sudan University of Science and Technology |
Mikhailenko S.D.,University LavalQuebec |
Rodrigues M.A.S.,Sudan University of Science and Technology |
And 2 more authors.
Journal of Power Sources | Year: 2016
Composite proton exchange membranes (PEMs) intended for fuel cell applications were prepared by embedding of various amounts of dispersed tri-sulfonic acid ethyl POSS (S-Et-POSS) and tri-sulfonic acid butyl POSS (S-Bu-POSS) in thin films of sulfonated poly ether-ether ketone. The electrical properties of the PEMs were studied by Impedance spectroscopy and it was found that their conductivity σ changes with the filler content following a curve with a maximum. The water uptake of these PEMs showed the same dependence. The investigation of initial isolated S-POSS substances revealed the properties of typical electrolytes, which however in both cases possessed low conductivities of 1. 17 × 10-5 S cm-1 (S-Et-POSS) and 3.52 × 10-5 S cm-1 (S-Bu-POSS). At the same time, the insoluble in water S-POSS was found forming highly conductive interface layer when wetted with liquid water and hence producing a strong positive impact on the conductivity of the composite PEM. Electrical properties of the composites were analysed within the frameworks of effective medium theory and bounding models, allowing to evaluate analytically the range of possible conductivity values. It was found that these approaches produced quite good approximation of the experimental data and constituted a fair basis for interpretation of the observed relationship. © 2015 Elsevier B.V.
Hashemi H.,University of KwaZulu - Natal |
Babaee S.,University of KwaZulu - Natal |
Mohammadi A.H.,University of KwaZulu - Natal |
Mohammadi A.H.,Institute Of Recherche En Genie Chimique Et Petrolier Irgcp |
And 3 more authors.
Journal of Chemical Thermodynamics | Year: 2015
Clathrate hydrate dissociation conditions were measured for four “alternative” refrigerants, viz. R404A, R406A, R408A and R427A. The experimental measurements were performed within the pressure range of (0.079 to 9.995) MPa and temperatures ranging from (272.7 to 288.7) K. An isochoric pressure-search method was used to perform the measurements. A thermodynamic model based on the van der Waals–Platteeuw (vdW–P) model was applied for the prediction of the dissociation conditions which were compared to the experimental measurements. The fluid phase was modeled using the MHV2 GE-EoS mixing rule along with the UNIFAC (original) activity model. The van der Waals–Platteeuw (vdW–P) model was used for the modeling of the hydrate phase. There was reasonable agreement between the experimental and predicted values. © 2015 Elsevier Ltd
PubMed | University LavalQuebec and Higher Institute of Aeronautics and Space
Type: | Journal: Frontiers in human neuroscience | Year: 2016
Given the important amount of visual and auditory linguistic information that pilots have to process, operating an aircraft generates a high working-memory load (WML). In this context, the ability to focus attention on relevant information and to remain responsive to concurrent stimuli might be altered. Consequently, understanding the effects of WML on the processing of both linguistic targets and distractors is of particular interest in the study of pilot performance. In the present work, participants performed a simplified piloting task in which they had to follow one of three colored aircraft, according to specific written instructions (i.e., the written word for the color corresponding to the color of one of the aircraft) and to ignore either congruent or incongruent concurrent auditory distractors (i.e., a spoken name of color). The WML was manipulated with an n-back sub-task. Participants were instructed to apply the current written instruction in the low WML condition, and the 2-back written instruction in the high WML condition. Electrophysiological results revealed a major effect of WML at behavioral (i.e., decline of piloting performance), electrophysiological, and autonomic levels (i.e., greater pupil diameter). Increased WML consumed resources that could not be allocated to the processing of the linguistic stimuli, as indexed by lower P300/P600 amplitudes. Also, significantly, lower P600 responses were measured in incongruent vs. congruent trials in the low WML condition, showing a higher difficulty reorienting attention toward the written instruction, but this effect was canceled in the high WML condition. This suppression of interference in the high load condition is in line with the engagement/distraction trade-off model. We propose that P300/P600 components could be reliable indicators of WML and that they allow an estimation of its impact on the processing of linguistic stimuli.
Giguere S.,Laval University |
Laviolette F.,Laval University |
Marchand M.,Laval University |
Tremblay D.,Laval University |
And 4 more authors.
PLoS Computational Biology | Year: 2015
The discovery of peptides possessing high biological activity is very challenging due to the enormous diversity for which only a minority have the desired properties. To lower cost and reduce the time to obtain promising peptides, machine learning approaches can greatly assist in the process and even partly replace expensive laboratory experiments by learning a predictor with existing data or with a smaller amount of data generation. Unfortunately, once the model is learned, selecting peptides having the greatest predicted bioactivity often requires a prohibitive amount of computational time. For this combinatorial problem, heuristics and stochastic optimization methods are not guaranteed to find adequate solutions. We focused on recent advances in kernel methods and machine learning to learn a predictive model with proven success. For this type of model, we propose an efficient algorithm based on graph theory, that is guaranteed to find the peptides for which the model predicts maximal bioactivity. We also present a second algorithm capable of sorting the peptides of maximal bioactivity. Extensive analyses demonstrate how these algorithms can be part of an iterative combinatorial chemistry procedure to speed up the discovery and the validation of peptide leads. Moreover, the proposed approach does not require the use of known ligands for the target protein since it can leverage recent multi-target machine learning predictors where ligands for similar targets can serve as initial training data. Finally, we validated the proposed approach in vitro with the discovery of new cationic antimicrobial peptides. Source code freely available at. © 2015 Giguère et al.
Renauld S.,University LavalQuebec |
Mohamed-Said L.,University LavalQuebec |
Macoir J.,University LavalQuebec |
Macoir J.,Institute University En Sante Mentale Of Quebecquebec
Multiple Sclerosis and Related Disorders | Year: 2016
Background Although cognitive impairments are common in patients with multiple sclerosis (MS), language impairments are not well defined. Objective The goal of this review was to examine the presence and nature of language disorders associated with MS. Method A search of PubMed and PsycINFO databases was conducted using combinations of the following terms: language disorders, language pathology, language impairment, multiple sclerosis, communication, language and speech. Studies were chosen based on the original language of the text, year of publication, peer-review status and specificity of the results regarding language and communication disorders. Results This review covers 30 articles from 13 countries. The studies involved patients with different types of MS. Various language impairments were reported in MS. However, since the methods used in the studies varied widely, it is difficult to draw any conclusions thus far. Conclusion Given the various cognitive deficits in MS, it is expected that higher language abilities would be affected. This aspect should be investigated in future studies. © 2016 Elsevier B.V.
Brochu P.,University LavalQuebec |
Sevigny S.,University LavalQuebec |
Giroux I.,University LavalQuebec
Journal of Gambling Issues | Year: 2015
Although the practice of online poker is associated with high rates of gambling problems, little is yet known about what distinguishes online poker players with different levels of gambling problems. Three groups of Texas Hold’em online poker players (low-risk (n = 7), at-risk (n = 7) and problematic (n = 3)), were compared in terms of their motivations to play, their emotions experienced during play and their perceptions about chance and skill. Thematic analysis from focus groups conducted reveals that the motivations to play and emotions reported in the groups are similar. The at-risk and problematic groups distinguish themselves from the low-risk group in their overestimation of their personal skill. The beliefs gathered through this study will contribute to the development or adaptation of erroneous beliefs’ questionnaires used with online poker players. © 2015, Centre for Addiction and Mental Health. All rights reserved.
Caron C.,University LavalQuebec |
Boudreau D.,University LavalQuebec |
Ritcey A.M.,University LavalQuebec
Journal of Materials Chemistry C | Year: 2015
Low-polydispersity europium-doped (H3O)Y3F10·xH2O single-crystal nanoparticles can be prepared via a simple reverse microemulsion method. The doping level of the particles can be varied by changing the relative concentration of europium to yttrium in the initial precursor mixture. Doping levels of up to 14 ± 2 at% can be attained without loss of the host crystal structure. Final europium concentrations, however, fall below those of the precursor solutions, suggesting that europium ions are less readily incorporated into the (H3O)Y3F10·xH2O crystal lattice than are yttrium ions. Emission spectra of the doped nanoparticles show sharp well-defined lines, which can be assigned to known europium transitions. The emission intensity increases linearly with increasing europium content. Europium ions within the nanocrystals exhibit excited-state lifetimes of 3-5 ms. These values are an order of magnitude greater than those of free ions in solution, indicating that ion incorporation in the yttrium fluoride matrix efficiently reduces non-radiative energy losses. Finally, data from time-resolved phosphorescence measurements suggests that europium ions within the particles are located in spectroscopically different environments which can be tentatively assigned to surface and core sites. © The Royal Society of Chemistry.
Juneau P.-M.,University LavalQuebec |
Garnier A.,University LavalQuebec |
Duchesne C.,University LavalQuebec
Biotechnology and Bioengineering | Year: 2016
Cell morphology is an important macroscopic indicator of cellular physiology and is increasingly used as a mean of probing culture state in vitro. Phase contrast microscopy (PCM) is a valuable tool for observing live cells morphology over long periods of time with minimal culture artifact. Two general approaches are commonly used to analyze images: individual object segmentation and characterization by pattern recognition. Single-cell segmentation is difficult to achieve in PCM images of adherent cells since their contour is often irregular and blurry, and the cells bundle together when the culture reaches confluence. Alternatively, pattern recognition approaches such as the undecimated wavelet transform multivariate image analysis (UWT-MIA), allow extracting textural features from PCM images that are correlated with cellular morphology. A partial least squares (PLS) regression model built using textural features from a set of 200 ground truth images was shown to predict the distribution of cellular morphological features (major and minor axes length, orientation, and roundness) with good accuracy for most images. The PLS models were then applied on a large dataset of 631,136 images collected from live myoblast cell cultures acquired under different conditions and grown in two different culture media. The method was found sensitive to morphological changes due to cell growth (culture time) and those introduced by the use of different culture media, and was able to distinguish both sources of variations. The proposed approach is promising for application on large datasets of PCM live-cell images to assess cellular morphology and growth kinetics in real-time which could be beneficial for high-throughput screening as well as automated cell culture kinetics assessment and control applications. © 2016 Wiley Periodicals, Inc.
PubMed | University LavalQuebec
Type: | Journal: Frontiers in physiology | Year: 2017
Prior peripheral hypoxia induced via remote ischemic preconditioning (IPC) can improve physical performance in male athletes through improved O