Mise au point d'une méthode moléculaire pour l'analyse de virucides

Les infections nosocomiales sont une cause majeure de complications dans les établissements de santé et représentent une grande partie des complications possibles chez les patients. Les norovirus ont été identifiés comme une source non négligeable d’infections nosocomiales. Cependant, il n’existe pas de traitement efficace pour ce type d’infection. Ainsi, la meilleure façon de combattre ces infections est la prévention de la transmission, souvent par le biais de désinfectants. Les méthodes actuelles d’analyse de désinfectants ne tirent pas avantage des avancées effectuées en biologie moléculaire. La plupart des analyses de désinfectants se basent sur une méthode permettant de calculer le titre viral par l’observation des effets cytopathiques sur une population de cellules hôtes nommée 50% Tissue Culture Infectious Dose (TCID50). Cependant, cette technique s’avère fastidieuse et des techniques plus récentes et sensibles de mesure du titre viral ont été développées. La méthode d’ICC (Integrated Cell Culture) qRTPCR est une méthode moléculaire par laquelle le matériel génétique viral est extrait d’une population de cellule hôte, pour ensuite être amplifié par qPCR en utilisant des amorces capables d’amplifier l’ARNm viral. Ce projet de maîtrise avait pour but de développer une méthode efficace d’analyse de désinfectants contre le norovirus en utilisant la méthode ICC qRT-PCR. Par la méthode TCID50, nous avons évalué l’efficacité d’une série de désinfectants dans le but de les comparer à la méthode moléculaire. Par conséquent, un protocole a été développé pour permettre l’amplification du matériel génétique du calicivirus félin, virus substitut du norovirus. Cependant, les désinfectants utilisés semblent avoir un effet sur la qualité de l’extraction de l’ARN viral, ce qui est un problème pour le développement de la méthode v ICC qRT-PCR. Des études utilisant différents désinfectants pourraient permettre de vérifier la validité de la méthode pour l’analyse de l’efficacité des virucides

A simple and efficient feedback control strategy for wastewater denitrification

Due to severe mathematical modeling and calibration difficulties open-loop feedforward control is mainly employed today for wastewater denitrification, which is a key ecological issue. In order to improve the resulting poor performances a new model-free control setting and its corresponding "intelligent" controller are introduced. The pitfall of regulating two output variables via a single input variable is overcome by introducing also an open-loop knowledge-based control deduced from the plant behavior. Several convincing computer simulations are presented and discussed.Comment: IFAC 2017 World Congress, Toulouse, Franc

Using Biofeedback while Immersed in a Stressful Videogame Increases the Effectiveness of Stress Management Skills in Soldiers

This study assessed the efficacy of using visual and auditory biofeedback while immersed in a tridimensional videogame to practice a stress management skill (tactical breathing). All 41 participants were soldiers who had previously received basic stress management training and first aid training in combat. On the first day, they received a 15-minute refresher briefing and were randomly assigned to either: (a) no additional stress management training (SMT) for three days, or (b) 30-minute sessions (one per day for three days) of biofeedback-assisted SMT while immersed in a horror/first-person shooter game. The training was performed in a dark and enclosed environment using a 50-inch television with active stereoscopic display and loudspeakers. On the last day, all participants underwent a live simulated ambush with an improvised explosive device, where they had to provide first aid to a wounded soldier. Stress levels were measured with salivary cortisol collected when waking-up, before and after the live simulation. Stress was also measured with heart rate at baseline, during an apprehension phase, and during the live simulation. Repeated-measure ANOVAs and ANCOVAs confirmed that practicing SMT was effective in reducing stress. Results are discussed in terms of the advantages of the proposed program for military personnel and the need to practice SMT

Développement et application de cas-tests dans le but de comparer des modèles d'échangeurs géothermiques verticaux

peer reviewedThe main objective of this paper is to establish a set of test cases for analytical verifications and intermodel comparisons of ground heat exchanger (GHX) models used in building simulation programs. Several test cases are suggested. They range from steady-state heat rejection in a single borehole to varying hourly loads with large yearly thermal imbalance in multiple borehole configurations. The usefulness of the proposed test cases is illustrated by running them with different GHX models. This comparison exercise has shown that 1-D models compare favourably well with the more elaborate 3-D models for relatively small simulation periods. The cyclic heat rejection/collection test has revealed some small deficiency in the load aggregation scheme of a particular model. Finally, the use of the asymmetric (cooling dominated) load profile test case for a bore field composed of 100 boreholes revealed that the borehole wall temperature predicted by two GHX models can differ by as much as 10oC after a 30 year simulation

Infrared supercontinuum generated in concatenated InF3 and As2Se3 fibers

We report on infrared supercontinuum (SC) generation through subsequent nonlinear propagation in concatenated step-index fluoride and As2Se3 fiber. These fibers were pumped by an all-fiber laser source based on an erbium amplifier followed by a thulium power amplifier. ZBLAN and InF3 fibers were compared for the concatenated scheme. The broadest SC produced was achieved by optimizing the length of the InF3 fiber. This arrangement allowed the generation of 200 mW infrared SC with high spectral flatness and spanning from 1.4 μm to 6.4 μm

292. Towards Large-Scale Manufacturing of Adeno-Associated Virus by Transient Transfection of HEK293 Suspension Cells in a Stirred Tank Bioreactor Using Serum-Free Medium

Adeno-Associated Virus (AAV) vectors showing safety profile in phase I clinical trials and its ability to transduce gene expression in various tissues have made it a vector of choice for gene delivery. There are different modes of AAV vector production and each has advantages and disadvantages. Here we demonstrated that the production of AAV by transient transfection in a serum-free medium using NRC's patented cGMP compliant human embryonic kidney HEK293 cell line (clone HEK293SF-3F6) adapted for growth in suspension can be readily scaled-up in stirred tank bioreactors. We employed triple-plasmid / polyethylenimine (PEI) based transient transfection technique. As a proof of concept, we demonstrated that nine serotypes of AAV (AAV-1 to AAV-9) encoding GFP can be produced by our cell line HEK293SF with yields of about 1E+13 genome-containing particles per liter (Vg/L). Depending on the serotypes 4-30% of AAV is present in the supernatant of the cell culture at 48hpt. The presence of plasmids and plasmid polyplexes that were not taken up by the cells or were not brought into the cell nucleus were removed by Iodixanol-ultracentrifugation method and Benzonase treatment before analyzing by real-time PCR. About 25% loss in genome containing viral particle counts were observed by Iodixanol purification method based on infectivity assay. Productions of AAV2 and AAV6 encoding GFP were demonstrated in 3L stirred tank bioreactors. Purification scheme was based on column chromatography - a scalable process. Different chromatography media, such as cation exchanger, anion exchanger and hydrophobic interaction chromatography, were tested with each AAV serotypes for their ability to adsorb and elute efficiently. The purification scheme was then adopted by integrating best chromatography medium and sequence dependent upon the AAV serotype in use. We demonstrated the purification scheme for AAV2 based on ion-exchange and hydrophobic interaction chromatography steps. The SDS-PAGE showed the purity of the final product and the presence of three capsid proteins VP1, VP2 and VP3 on Western blot corresponding to the only three bands present in the final product on SDS-PAGE. To extend the storage life of AAV we explored lyophilization technique to study the stability of AAV2 and AAV6 under lyophilized conditions. The AAV2 and AAV6 were stable for over 40 weeks based on infectivity assay. We demonstrated the scalability of the process up to 45L. Productions tested in 20 and 500 mL cultures in shake flasks were scaled up in 2 and 45L cultures (in 3- and 60-L stirred tank bioreactors, respectively). The volumetric yields and purification recoveries were comparable at all of these production scale levels demonstrating scalability of transient transfection at even larger scale is possible to generate material necessary for dosages required for gene therapy application

Attentes du personnel infirmier de la relève envers l’employeur pour favoriser l’engagement professionnel : un premier jalon pour la conception d’interventions organisationnelles au Québec (Canada)

Introduction: Poor work conditions jeopardize the quality of nursing jobs and increase turnover and attrition rates, especially for early career nurses and licensed practical nurses. Understanding perspectives of the nursing staff on work engagement is essential to develop innovative and responsive organizational interventions. Objectives: 1- Define the expectations of early career nursing staff with respect to their workplace in order to support work engagement 2- Identify priority actions to support work engagement at organizational level. Methods: A mixed-methods research design based on a conceptual mapping approach was used. Early career nurses and licensed practical nurses (N=14) working in a semi-urban integrated health and social services center in Quebec (Canada) were asked the following question: “What can the workplace do to promote work engagement?” Multidimensional scaling and cluster analysis were used to organize the 49 statements provided by the nursing staff. At the same time, participants prioritized actions by rating the “importance” and “probability of a successful implementation” of each statement. Results: Nursing staffs’ expectations toward their workplace in order to support work engagement were: attractive working conditions, positive leadership, safe working conditions, professional development opportunities, and personalized career path. More specifically, the priority actions identified were: showing respect, providing a healthy environment and avoiding transfer to unwanted departments. Discussion and conclusion: The results suggest several actions to promote work engagement of early career nursing staff working in semi-urban settings in Quebec, including providing human and material resources, implementing a positive organizational culture, and exercising benevolent leadership. Introduction : Les conditions de travail difficiles compromettent la qualité des emplois infirmiers, accentuent le roulement ainsi que l’attrition, et ce, particulièrement pour le personnel infirmier de la relève. La compréhension des perspectives du personnel infirmier sur l’engagement professionnel est essentielle pour élaborer des interventions organisationnelles innovantes et adaptées en ce sens. Objectifs : L’étude vise à 1- définir les attentes du personnel infirmier de la relève face à l’employeur pour favoriser l’engagement professionnel et 2- identifier les actions organisationnelles prioritaires pour favoriser l’engagement professionnel. Méthodes : Suivant un devis de recherche mixte selon une démarche de cartographie conceptuelle, des infirmières et infirmières auxiliaires de la relève (N=14) dans un centre intégré de santé et de services sociaux (CISSS) semi-urbain du Québec (Canada) ont été invitées à répondre à la question : « Que peut faire l’employeur pour favoriser l’engagement professionnel? ». Des analyses statistiques d’échelonnement multidimensionnel et en grappe ont permis d’organiser les 49 énoncés formulés par le personnel infirmier. Parallèlement, les participantes ont établi les actions prioritaires en cotant « l’importance » et « la probabilité de succès d’implantation » de chaque énoncé. Résultats : Les attentes du personnel infirmier envers leur employeur sont : des conditions de travail attractives, un leadership positif, des conditions de pratique sécuritaires, le soutien au développement professionnel et un cheminement personnalisé. Plus précisément, les actions prioritaires pour l’employeur consistent à : démontrer du respect, offrir un environnement sain et éviter les déplacements dans des départements non souhaités. Discussion et conclusion : Les résultats suggèrent plusieurs pistes d’actions pour favoriser l’engagement professionnel du personnel infirmier de la relève, en contexte semi-urbain au Québec, notamment : l’offre de ressources humaines et matérielles, l’implantation d’une culture organisationnelle positive et l’exercice d’un leadership bienveillant.  &nbsp