Stress en milieu de travail : une intervention individuelle, organisationnelle et communautaire

Près de 9 000 personnes travaillent et vivent de 9 à 5 dans des tours climatisées. Tout est en place pour produire et consommer davantage. Lorsqu'il fait froid, l'air climatisé est là pour nous dégeler, et lorsqu'il fait chaud, il est toujours là pour garder l'air ambiant à 20° C afin de nous faire oublier qu'à l'extérieur la température pourrait nous inciter à faire une sieste. De plus, le décor aseptique et impersonnel des petits bureaux nous fait souvent penser au « rat maze » de Skinner. Dans cet article, notre intention n'est pas de vous endormir en vous racontant l'histoire des tours à bureaux, mais plutôt de vous livrer les résultats d'une expérience dans le domaine de la santé communautaire qui se vit dans cet édifice depuis près de deux ans. Il s'agit du programme Prévention-Santé en milieu de travail du CLSC Centre-Ville à Montréal qui met l'accent sur un phénomène communément appelé le stress. L'originalité de ce programme réside dans le fait que l'intervention menée par une équipe multidisciplinaire s'est centrée sur une population du secteur tertiaire de l'industrie.This article result from a reflection on the intervention of a multidisciplinary group which worked for almost two years on a preventive health program in a work setting. The milieu chosen comprises offices workers in a downtown Montréal building. The program's originality stems from its intervention at the individual, organizational and community levels* The results of the intervention described in this article will lead to the assumption of responsability for such a program by the employees and employers in the setting

Le rapport à l’école et au travail pendant l’adolescence. Travailler pendant les études permet-il de « construire des certitudes »?

L’adolescence est à la fois une étape de transition et de construction de l’identité au cours de laquelle se présentent aujourd’hui de nombreuses incertitudes face à l’insertion professionnelle future. En examinant le rapport à l’école et au travail pendant l’adolescence au moyen d’une étude exploratoire menée par entretiens semi-dirigés, cet article montre comment le fait de travailler permet de construire des certitudes pour les jeunes en regard de l’acquisition d’expériences de travail et de la construction de l’autonomie tant sur le plan social que financier et professionnel. Cependant, ce rapport généralement positif au travail ne trouve pas d’équivalence dans le rapport des jeunes à l’école, davantage marqué par la nécessité, l’obligation et la contrainte. De plus, le fait de travailler pendant les études semble avoir des effets plutôt négatifs sur les dimensions relationnelles de la vie des jeunes interviewés et les conséquences des rapports opposés à l’école et au travail ne sont pas négligeables. Quelques pistes de réflexion pour la recherche et l’intervention sont soulevées en guise de conclusion

Computational framework for fracture of graphite bricks in an AGR core

Life-extension of EDF Energy's existing nuclear fleet is based on an assumption of continued safe operation. Potential fracture of graphite bricks in the nuclear reactor core of a power station represents an unknown variable in the equation. An understanding of the nature of this phenomenon and the impact on operation of the power station is desired. This work prepares the way for the future study of fracture in graphite bricks in a reactor core subject to dynamic excitation. Methodology to couple a multi-body finite element contact code to a crack propagation code is thus developed. Three important scientific contributions have been made: (i) An optimisation problem formulated on a smooth manifold to yield the rotation responsible for infinitesimal rigid body motion. This involves an iterative scheme in the form of Newton's method that takes into account the geometry of the underlying parameter space. There are no issues with singularities or additional computations in each iteration to scale the solution onto the manifold. (ii) An energy consistent crack initiation criterion for brittle material where nucleation is treated as a sudden and discrete rupture event at the macroscopic level. At the heart of the criterion is the finite difference form of the energy release rate; an expression for the characteristic length is derived and the change in total potential energy is obtained from an asymptotic argument involving the topological derivative. The criterion can predict crack onset at a sharp or blunt notch. Fracture toughness and material strength are the only input requirements. (iii) Algorithms related to the detection of sharp notches in a tetrahedral finite element mesh and a general computational procedure for evaluation of non-local crack initiation criteria. The only tool in the implementation of these algorithms is C++11. There is no need for a complex data structure storing all incidence information. Unordered associative containers in the standard library are exploited in the design of these rather efficient algorithms, which cover surface extraction and provide connectivity of the edges representing a sharp notch tip. A mesh re-generation routine for purposes of refinement at the sharp notch tips has also been developed

Accounting for the Effects of Power System Controllers and Stability on Power Dispatch and Electricity Market Prices

Recently, the widespread use of power system controllers, such as PSS and FACTS controllers, has led to the analysis of their effect on the overall stability of power systems. Many studies have been conducted to allocate FACTS controllers so that they achieve optimal power flow conditions in the context of Optimal Power Flow (OPF) analysis. However, these studies usually do not examine the effect of these controllers on the voltage and angle stability of the entire system, considering that the types of these controllers and their control signals, such as reactive power, current, or voltage, have significant effect on the entire system stability. Due to the recent transition from government controlled to deregulated electricity markets, the relationship between power system controllers and electricity markets has added a new dimension, as the effect of these controllers on the overall power system stability has to be seen from an economic point of view. Studying the effect of adding and tuning these controllers on the pricing of electricity within the context of electricity markets is a significant and novel research area. Specifically, the link among stability, FACTS controllers and electricity pricing should be appropriately studied and modelled. Consequently, in this thesis, the focus is on proposing and describing of a novel OPF technique which includes a new stability constraint. This technique is compared with respect to existent OPF techniques, demonstrating that it provides an appropriate modelling of system controllers, and thus a better understanding of their effects on system stability and energy pricing. The proposed OPF technique offers a new methodology for pricing the dynamic services provided by the system's controllers. Moreover, the new OPF technique can be used to develop a novel tuning methodology for PSS and FACTS controllers to optimize power dispatch and price levels, as guaranteeing an adequate level of system security. All tests and comparisons are illustrated using 3-bus and 14-bus benchmark systems

Class 3 obesity in a multidisciplinary metabolic weight management program : the effect of preexisting Type 2 diabetes on 6-month weight loss

Introduction. Class 3 obesity (BMI ≥ 40 kg/m2) is a growing health problem worldwide associated with considerable comorbidity including Type 2 diabetes mellitus (T2DM). The multidisciplinary medical management of obesity can be difficult in T2DM due to potential weight gain from medications including sulphonylureas and insulin. However, newer weight-neutral/losing diabetes medications can aid additional weight loss. The aim of this study was to compare weight loss outcomes of patients with and without T2DM, and in patients with T2DM, to compare diabetes outcomes and change in medications at 6 months. Methods. All patients entering a multidisciplinary weight management metabolic program in a publicly funded hospital clinic in Sydney between March 2018 and March 2019, with BMI ≥ 40 kg/m2 and aged ≥18 years were included. Data was collected from patient clinical and electronic notes at baseline and 6 months. Results. Of the 180 patients who entered the program, 53.3% had T2DM at baseline. There was no difference in percentage weight loss in those with or without T2DM (4:2±4:9% vs. 3:6±4:7%, p = 0:35). Additionally, T2DM patients benefited from a 0.47% reduction in HbA1c (p < 0:01) and a reduction in the number of medications from baseline to 6 months (1:8±1:0/patient vs. 1:0±1:2/patient, p < 0:001). T2DM patients who started on weigh-neutral/losing medications in the program lost more weight than those started on weight-gaining medications (7:7±5:3% vs. 2:4±3:8%, p = 0:015). Conclusions. Patients with class 3 obesity had significant weight loss at 6 months in this program. Patients with T2DM at baseline had comparable weight loss at 6 months, a significant improvement in glycaemic control, and a reduction in diabetes medication load. Additionally, patients with T2DM who were started on weight-neutral/losing medications lost significantly more weight than those started on weight-gaining medications, and these medications should be preferentially used in class 3 obesity and comorbid T2DM

Brief Report: Sensorimotor Gating in Idiopathic Autism and Autism Associated with Fragile X Syndrome

Prepulse inhibition (PPI) may useful for exploring the proposed shared neurobiology between idiopathic autism and autism caused by FXS. We compared PPI in four groups: typically developing controls (n = 18), FXS and autism (FXS+A; n = 15), FXS without autism spectrum disorder (FXS−A; n = 17), and idiopathic autism (IA; n = 15). Relative to controls, the FXS+A (p < 0.002) and FXS−A (p < 0.003) groups had impaired PPI. The FXS+A (p < 0.01) and FXS−A (p < 0.03) groups had lower PPI than the IA group. Prolonged startle latency was seen in the IA group. The differing PPI profiles seen in the FXS+A and IA indicates these groups may not share a common neurobiological abnormality of sensorimotor gating

Scaling Up Sustainable Land Management and Restoration of Degraded Land

With current rates of land degradation reaching ten to twelve million ha per year, there is an urgent need to scale up and out successful, profitable and resource-efficient sustainable land management practices to maintain the health and resilience of the land that humans depend on. As much as 500 million out of two billion ha of degraded land, mainly in developing countries, have restoration potential, offering an immediate target for restoration and rehabilitation initiatives.1 In the past, piecemeal approaches to achieving sustainable land management have had limited impact. To achieve the ambitious goals of alleviating poverty, securing food and water supplies, and protecting the natural resource base, we need to recognize the inter-connectedness of the factors driving land degradation, so that solutions can be taken to scale, transforming management practices for millions of land users. An analysis of the critical barriers and incentives to achieve scaling up suggests that the most appropriate options should be selected through the involvement of stakeholders at all levels, from local to national and international. New incentives for land managers as well as the public and private sectors are required to achieve a land degradation-neutral world