134 research outputs found

    La formation des intervenants en formation à distance peut-elle jouer un rôle dans la persévérance des apprenants? /

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    Comprend des références bibliographiques

    Étude de la distribution de Salmonella spp. dans les tissus chez le porc suite à une infection naturelle et expérimentale

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    Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal

    Caractérisation des impacts sur les écosystèmes, de l'utilisation des terres associées à la foresterie

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    Un système basé sur le concept de naturalité, qui évalue la similarité par rapport à la forêt naturelle, a été élaboré dans le but d'évaluer les impacts de la foresterie. Ce système repose sur l'identification d'indicateurs de naturalité sensibles aux enjeux d'aménagement forestier reconnus et utilise des mesures disponibles à partir des cartes écoforestières, des études sur la modélisation des écosystèmes et des données historiques. Ce système fournit une valeur unique permettant de représenter l'effet conjugué de diverses pratiques, incluant la protection, sur les principales caractéristiques de l'écosystème forestier. D'abord développé pour la pessière, puis adapté pour la sapinière, ce système fonctionne de manière bidirectionnelle, permettant d'évaluer aussi bien la dégradation, que l'amélioration de la qualité des écosystèmes résultant d'objectifs de restauration et de mesures de mitigation. Ce système a été utilisé pour comparer l'impact sur la qualité des écosystèmes à l'échelle du paysage de divers scénarios sylvicoles considérés simultanément, comme dans la sapinière, où l'effet combiné de coupes progressives irrégulières et d'une réduction de la révolution de 70 à 50 ans pour les scénarios équiennes (coupe avec protection de la régénération et des sols et plantation) a été examiné. Son utilisation permet également d'éclairer la réflexion pour la détermination d'objectifs de protection aptes à limiter les pertes de biodiversité, tout en tenant compte de l'intensité de l'aménagement pour la production de bois. Ainsi, pour trois unités d'aménagement forestier de la pessière, considérant la combinaison de scénarios sylvicoles actuellement utilisés pour régénérer les forêts productives, le niveau de protection devrait être doublé et atteindre 35% de la superficie forestière afin de limiter d'éventuelles pertes d'espèces. Aussi, les résultats montrent qu'il serait plus avantageux au plan environnemental d'intensifier la production de bois d'espèces indigènes sur une petite proportion du territoire forestier tout en assurant une protection stricte sur la portion non productive, plutôt qu'un aménagement extensif sur la vaste majorité du territoire forestier. Dans le cadre du développement de l'analyse de cycle de vie (ACV) chapeauté par le Programme des Nations Unies pour l'environnement et la Société de toxicologie et de chimie de l'environnement (UNEP-SETAC), les impacts de produits ou services sur la qualité des écosystèmes sont évalués par le biais des impacts de l'utilisation des terres sur la biodiversité. Pour l'intégration à l'ACV, une courbe provisoire reliant l'indice de naturalité à la perte potentielle de biodiversité exprimée sur la base de la richesse en espèces provenant de la base de données PREDICTS est proposée. L'application de cette courbe a permis l'obtention de scores d'impact cohérents avec la proportion d'espèces disparues (PDF) estimée à partir de la naturalité et conformes aux connaissances relatives aux impacts de l'aménagement forestier. Toutefois, les résultats s'avèrent sensibles au paramétrage de la courbe et l'analyse de sensibilité a montré qu'il existait des risques de distorsion, voire d'obtention de résultats erronés. L'évaluation des scores d'impact de l'ACV résultant de l'application de trois scénarios sylvicoles distincts évalués concomitamment à l'application d'un gradient de la proportion du territoire forestier en protection stricte, apporte un éclairage sur le comportement du modèle utilisé pour l'évaluation de la qualité des écosystèmes en ACV si l'on tient compte de l'intensité de l'aménagement. Le modèle ACV multiplie deux paramètres aux effets opposés et non-linéaires : le PDF qui augmente avec l'intensité de l'aménagement, alors que la superficie requise pour produire 1m3 de bois diminue. Étant donné les risques associés à la présence d'effets non-linéaires non contrôlés, le modèle ACV peut fournir des résultats erratiques ne reflétant pas toujours l'effet sur l'aspect à protéger qui correspond ici à la qualité des écosystèmes. Conséquemment, dans l'état actuel des choses, le modèle ACV ne devrait pas être utilisé pour la prise de décision en matière d'utilisation des terres. De plus amples recherches relatives aux propriétés mathématiques des relations en cause sont nécessaires afin de vérifier la possibilité de contrôler ces effets de manière à assurer l'obtention de résultats reflétant la qualité des écosystèmes plutôt que celui de la superficie requise, déterminée par la productivité, et ainsi respecter la hiérarchisation des impacts associés à la qualité des écosystèmes évaluée à l'échelle d'un territoire et éviter des recommandations qui conduiraient à occasionner davantage de dommages.An evaluation system based on the concept of naturalness, which measures the similarity against natural forests, has been developed to assess the impacts of forestry. This assessment system relies on naturalness indicators sensitive to recognized forest management issues, and uses measures from eco-forest maps, results from ecosystem modeling and historical data. The naturalness assessment model provides a unique index allowing to assess the combined effect of different forest management practices including protection, on the main characteristics of forest ecosystems. Initially developed for black spruce forests, then adapted for balsam fir forests, the naturalness assessment model performs bi-directional evaluations allowing the assessment not only of ecosystem degradation but also of its improvement with restoration or mitigation measures. Among potential applications of the naturalness assessment model, its usefulness has been demonstrated for comparing the impact at the landscape level of different silvicultural scenarios combinations. In the balsam fir forest, we examined the combined effect of irregular shelterwood cutting along with the rotation reduction form 70 to 50 years for the even-aged scenarios of careful logging and plantation. The naturalness assessment model can also be used to shed light on protection levels needed to limit biodiversity losses. In three forest management units of the black spruce forest, considering the current mix of silvicultural scenarios for wood production, the protection level should be doubled to attain 35% of the forest area, to limit species losses. Results indicate that it would be better for the environment to intensify forest management using indigenous species over a small proportion of the forest territory while insuring strict protection over the remaining portion, compared with an extensive forest management applied over most of the forested area. Life cycle analysis (LCA) development under the guidance of the United Nations Environment Program and Society of Environmental Toxicology and Chemistry (UNEP-SETAC), provides impact evaluation of products or services on ecosystem quality through impact of land use on biodiversity. In order to include naturalness results in LCA, a provisional curve relating naturalness index to potentially disappeared fraction of species (PDF) has been developed using species richness data from the PREDICTS database. The provisional curve application lead to LCA impact scores consistent with the PDF estimated from naturalness and the existing knowledge about the effects of forest management. However, the sensitivity analysis showed that results are sensitive to the curve parametrization and there are risks of distortion and even contradictory results. LCA impact scores related to the application of three different silvicultural scenarios each combined with a gradient of the proportion of forest area in strict protection shed a light on the LCA model behaviour when considering management intensity. The LCA model multiplies two parameters having opposite non-linear effects: the PDF, which is rising with the intensification of the management, while the area required to produce 1m3 of wood, is diminishing. Considering the risks related to the uncontrolled non-linear effects involved in the LCA model, this could lead to erratic results that do not reflect the effect on the safeguard subject corresponding here to the quality of ecosystems. Therefore, the LCA model should not be used for decision making related to land use decision. More research is required to investigate the mathematical relationships involved to verify if and how issues related to non-linear effects in LCA model could be properly addressed and insure that impact scores results reflect ecosystem quality instead of the area required for wood production, conserve the hierarchical structure of impacts and avoid recommendations that could produce more damage

    Use of Serology to evaluate the impact of clinical salmonellosis in swine on the herd status and on the contamination of pig carcasses from affected herds.

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    Clinical episodes of salmonellosis, often associated with high levels of herd contamination and caused by serotypes other that Choleraesuis, are now observed in Canada. We were thus particularly interested, in this study, to examine the impact of clinical salmonellosis on the serological status of the affected herds and to determine if clinical salmonellosis can be related with an increased level of contamination of carcasses of animals from these herds, after the slaughter process. The Diakit was used as screening test for the detection of Salmonella antibodies in finishing pigs from affected (n=15) and non affected (n=15) herds. The percentage of animal serologically positive to Salmonella in herds that experienced clinical salmonellosis was significantly higher than in herds without clinical sign of salmonellosis (30.0% vs 11.1%, p=0.003). Furthermore, a higher level of contamination of carcasses by Salmonella was found in carcasses from animals from those herds (13.6% vs 2.9%, p=0.048) at slaughterhouse. Herds that were found infected by various serovars from serogroups B (Typhimurium, Derby, Agona, Brandenburg, Heidelberg), C (Ohio, Infantis, Manhattan), E (Senftenberg, Anatum) and N (Urbana) were detected by the ELISA

    Relationship between Adherence Level to Statins, Clinical Issues and Health-Care Costs in Real-Life Clinical Setting

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    AbstractObjectiveStatins have been shown to reduce the risk of major cardiovascular disease. We recognize that there is a major gap between the use of statins in actual practice and treatment guidelines for dyslipidemia. Low adherence to statins may have a significant impact on clinical issues and health-care costs. The objective is to evaluate the impact of low adherence to statins on clinical issues and direct health-care costs.MethodsA cohort of 55,134 patients newly treated with statins was reconstructed from the Régie de l'Assurance Maladie du Québec and Med-Echo databases. Subjects included were aged between 45 and 85, initially free of cardiovascular disease, newly treated with statins between 1999 and 2002, and followed-up for a minimum of 3 years. Adherence to statins was measured in terms of the proportion of days' supply of medication dispensed over a defined period, and categorized as ≥80% or <80%. The adjusted odds ratio (OR) of cardiovascular events between the two adherence groups was estimated using a polytomous logistic analysis. The mean costs of direct health-care services were evaluated. A two-part model was applied for hospitalization costs.ResultsThe mean high adherence level to statins was around to 96% during follow-up; and this value was at 42% for the low adherence level. The patients with low adherence to statins were more likely to have coronary artery disease (OR 1.07; 95% confidence interval [CI], 1.01–1.13), cerebrovascular disease (OR 1.13; 95% CI 1.03–1.25), and chronic heart failure within 3-year period of follow-up (OR 1.13; 95% CI 1.01–1.26). Low adherence to statins was also associated with an increased risk of hospitalization by 4% (OR 1.04; 95% CI 1.01–1.09). Among patients who were hospitalized, low adherence to statins was significantly associated with increase of hospitalization costs by approximately $1060/patient for a 3-year period.ConclusionLow adherence to statins was correlated with a higher risk of cardiovascular disease, hospitalization rate, and hospitalization costs. An increased level of adherence to statins agents should provide a better health status for individuals and a net economic gain

    Achieving carbon neutrality for a future large greenhouse gas emitter in Quebec, Canada: a case study

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    To reach the Paris Agreement targets of holding the global temperature increase below 2 °C above the preindustrial levels, every human activity will need to be carbon neutral by 2050. Feasible means for industries to achieve carbon neutrality must be developed and assessed economically. Herein we present a case study on available solutions to achieve net-zero carbon from the get-go for a planned liquefied natural gas (LNG) plant in Quebec, which would classify as a large Canadian greenhouse gas (GHG) emitter. From a literature review, available options were prioritized with the promoter. Each prioritized potential solution is discussed in light of its feasibility and the associated economic opportunities and challenges. Although net-zero carbon is feasible from the get-go, results show that the promoter should identify opportunities to reduce as much as possible emissions at source, cooperate with other industries for CO2 capture and utilization, replace natural gas from fossil sources by renewable sources and offset the remaining emissions by planting trees and/or buying offsets on the compliance and voluntary markets. As some of these solutions are still to be developed, to ensure timely net-zero pledge for the lifespan of the LNG plant, a portfolio and progressive approach to combine offsets and other options is preferable

    Longitudinal and sex measurement invariance of the affective neuroscience personality scales

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    The Affective Neuroscience Personality Scales (ANPS) is a personality instrument based on six evolutionary-related brain systems that are at the foundation of human emotions and behaviors: SEEKING, CARING, PLAYFULNESS, FEAR, ANGER, and SADNESS. We sought to assess for the short and long versions of the ANPS: (a) the longitudinal measurement invariance and long-term (4-year) stability and (b) the sex measurement invariance. Using data from a Canadian cohort (N = 518), we used single-group confirmatory factor analysis to assess longitudinal invariance and multiple-group confirmatory factor analysis to assess sex invariance, according to a five-step approach evaluating five invariance levels (configural, metric, scalar, residual, and complete). Results supported full longitudinal invariance for both versions for all invariance levels. Partial residual invariance was supported for sex invariance. The long-term stability of both versions was good to excellent. Implications for personality assessment and ANPS development are discussed

    The development of the MENTOR_D nursing intervention : supporting family involvement in delirium management

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    Background Although families are increasingly seen as allies to improve delirium management and reduce its consequences, their involvement in the postcardiac surgery setting is challenging considering patients' critical state and short hospital stay. To our knowledge, no theory-based nursing intervention exists that optimally supports the involvement of families in delirium management in the context of postcardiac surgery. Objectives We aimed to develop MENTOR_D, a nursing intervention to support the involvement of families in delirium management. Methods MENTOR_D was developed based on Sidani and Braden's (2011) intervention development framework. Narrative literature reviews paired with the clinical experience of an expert committee were used to inform these three steps: (1) develop an understanding of the problem under study; (2) define the objectives of the intervention and identify a theoretical framework for highlighting strategies to be used in the intervention; and (3) operationalize the intervention and identify its anticipated outcomes. Results As a result of the three steps, the MENTOR_D nursing intervention relies on a caring–mentoring relationship between a nurse and the family. The aim of MENTOR_D is to increase the presence of the family at their relative's bedside and their involvement in delirium management. MENTOR_D's content is delivered over three phases that are organised around the visits of the family at the patient's bedside. During these phases, families used their knowledge of the patient to tailor the delirium management actions. These actions include orientation and reminiscence and were aimed at diminishing anxiety and increasing sense of self-efficacy in families and diminishing delirium severity and improving recovery in patients. Conclusions A deep understanding of the underlying mechanisms of an intervention is key in its success to reach the targeted goals of effectiveness in practice. This understanding can be achieved through the careful development of a theory of the intervention before the operationalisation of its components and its testing. The proposed paper presents the theory of the MENTOR_D intervention, that is, its conceptualization and proposed mechanisms of action. Implications for practice As delirium continues to be a major complication, this intervention is a promising solution to increase families' involvement in delirium management and highlights the support that nurses can offer to facilitate this involvement. With its use in future studies and practice, it can be further refined
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