Éditeur(s) : HAL CCSD
Résumé : International audience
The aim was to identify patterns of work organization characteristics using data from epidemiological surveillance program of musculoskeletal disorders (MSD) implemented in the Pays de la Loire region between 2002 and 2005. A total of 3710 workers were included and completed a administered questionnaire including 16 organizational variables. Ascendant hierarchical clustering (AHC) of organizational variables and AHC of workers had identified five patterns of work organization characteristics: technical constraints and weak decision latitude; internal/external demand and mean decision latitude; weak pace constraints and mean decision latitude; internal/external demand and high decision latitude; weak pace constraints and high decision latitude. Relationships with MSD diagnosed by occupational physicians were then studied.
The specific health programs (SHP) are one of the four mechanisms of prevention planned by the Health and Safety at work Law in the province of Quebec. If the Law appoints only a responsible doctor, it is in reality Health at work teams (HWT) that develop these SHP. In this communication, based on the model of the working situation and the diagram of inter professional practices of collaboration, we study the practices of inter professional collaboration (CIP) in the HWT. The observed practices vary between independent practices, in parallel, of consultation, of dialogue and in shared services. Formalization of the teams, coordination of communication, leadership, respect and professional identities influence particularly the practices of CIP.
L’objectif était d’identifier des patterns de caractéristiques d'organisation du travail à partir des données du programme de surveillance épidémiologique des troubles musculo-squelettiques (TMS) mis en œuvre dans les Pays de la Loire entre 2002 et 2005. Au total, 3 710 salariés ont été inclus et ont répondu à un questionnaire comportant notamment 16 variables organisationnelles. Une classification ascendante hiérarchique (CAH) des variables organisationnelles puis une CAH des salariés ont permis d’identifier cinq patterns de caractéristiques d’organisation du travail : contraintes techniques et faible latitude décisionnelle ; demande interne/externe et latitude décisionnelle moyenne ; faibles contraintes de rythme et latitude décisionnelle moyenne ; demande externe/interne et forte latitude décisionnelle ; faibles contraintes de rythme et forte latitude décisionnelle. Les associations avec les TMS diagnostiqués par des médecins du travail ont ensuite été étudiées.
Actes du 50ème congrès de la Société d'Ergonomie de Langue Française
Paris, France

halshs-01307785
https://halshs.archives-ouvertes.fr/halshs-01307785

Éditeur(s) : HAL CCSD Springer-Verlag Berlin Heidelberg
Résumé : International audience
The main biological function of reaction wood is to act as " muscle " for trees, enabling them to control their posture. The key property to achieve this function is the development of high mechanical stress during the formation of reaction wood cells, called " maturation strains ". Actually, reaction wood formation is basically the asymmetric formation of wood around the tree circumference, with higher maturation strains on the side where reaction wood is formed than on the opposite side. This asymmetry enables stems to bend upward or to compensate for the downward bending induced by gravity. At the cross section level, the performance in this biological function is linked not only to the magnitude of this asymmetry but also to an effect of the cross-sectional size (diameter) of the stem. Eccentric growth and variations in wood mechanical stiffness are second order effects that can modify this performance. Differences in maturation strains between reaction and non-reaction woods are related to their specific cell wall structure and composition. The swelling of the cell wall matrix during maturation and the effect of microfibril angle explain the differences in maturation strains between normal and compression wood. However, this mechanism fails in explaining the high maturation shrinkage of tension wood, and several hypotheses at the molecular levels are still under debate. How trees perceive their gravitational disequilibrium is also an open question for physiologists. Integrative biomechanical modelling (from the polymer level to the cell wall, cross section and whole tree levels) enables defining key variables that explain the performance of reaction wood as a system that insures the stem motricity. Maturation strains can be precisely measured only in recently formed wood at the tree surface, but their changes during the whole tree life can also be estimated by retrospective dendrochronological analysis through structural markers of reaction wood. Lastly, wood in living trees ensures general storage, defence, vascular and skeletal functions, that ask general questions about synergies and trade-offs as the structural characteristics of reaction wood can affect all these functions.
The Biology of Reaction Wood

ISBN : 978-3-642-10813-6
hal-01452085
https://hal.archives-ouvertes.fr/hal-01452085
https://hal.archives-ouvertes.fr/hal-01452085/document
https://hal.archives-ouvertes.fr/hal-01452085/file/Chap_Gril_al_Biomechanical_action_biological_functions_2014.pdf