Buttock pressure management of able-bodied people seated on a rigid surface for two hours.

International audienceIt is now well known that deep pressure ulcers are due to excessive pressure intensity (leading to soft tissues internal strains above 50 % for some minutes) and prolonged compression (leading to internal strains above 20 % for about two hours). This paper aims at better understanding why able-bodied individuals put in quite extreme conditions (i.e seated for 2 hours long on a rigid surface) do not get pressure ulcers. Thirty young healthy subjects agreed to stay seated on a rigid surface during two hours while watching a movie. The buttocks/seat interface pressures were recorded by a pressure mapping system

Regularity of BSDEs with a convex constraint on the gains-process

Abstract We consider the minimal super-solution of a backward stochastic differential equation with constraint on the gains-process. The terminal condition is given by a function of the terminal value of a forward stochastic differential equation. Under boundedness assumptions on the coefficients, we show that the first component of the solution is Lipschitz in space and 1 2 -Hölder in time with respect to the initial data of the forward process. Its path is continuous before the time horizon at which its left-limit is given by a face-lifted version of its natural boundary condition. This first component is actually equal to its own face-lift. We only use probabilistic arguments. In particular, our results can be extended to certain non-Markovian settings

Feeding ecology of Southern Ocean seastars inferred from stable isotopes ratios

The Southern Ocean is currently subjected to strong and contrasted impacts of climate change. The Western Antarctic Peninsula is one of the most rapidly warming regions of the world, resulting in sea ice cover decreases. Increasing seawater temperature and sea ice cover reduction in Western Antarctic Peninsula and associated regions will likely impact food web functioning through temperature-related changes in consumer physiology, modifications of benthic community structure (e.g. expansion of exogenous species such as predatory crabs), modifications of benthic-pelagic coupling intensity or disruption of benthic production. Asteroids (Echinoderms) are an important group of southern benthos. This group also has a great trophic variability and is potentially more resistant than other organisms to temperature changes (Peck et al. 2008). Consequently, they will be likely impacted by modifications in food webs functioning rather by direct warming and investigating their trophic ecology is necessary to infer how climate change will impact them. In this context, the aim of this study is to use stable isotopes ratios of C, N and S to infer sea stars trophic ecology. 16 species of sea stars spanning 10 different families sampled in multiple and contrasted habitats across Subantarctic (South Georgia, South Sandwich Islands, Falkland Islands) and Antarctic (South Shetland Islands, South Orkney Islands, Western Antarctic Peninsula) locations. In total, tegument samples from 213 specimens was analysed. Diversity and plasticity of asteroid diet along Southern Ocean coasts were explored through isotopic niche parametrisation (e.g. niche width and overlap between species and/or populations; Jackson et al. 2011). The data will also be used in a larger scale research project on the trophic ecology of Antarctic sea stars. This project will notably compare trophic resources supporting asteroid communities in Western Antarctic Peninsula, where sea ice cover is decreasing, and in Terre Adélie, where sea ice cover is increasing (Parkinson & Cavalieri 2012). Ultimately, this project will help understanding which ecological processes determine how an animal group copes with environmental modifications linked to climate change

The genotype 3-specific hepatitis C virus core protein residue phenylalanine 164 increases steatosis in an in vitro cellular model.: HCV genotype 3-specific steatosis

International audienceBackground and aims: The prevalence and severity of liver steatosis are higher in patients infected with genotype 3 hepatitis C virus (HCV) than in patients infected with other genotypes. HCV core protein is known to affect lipid metabolism, inducing lipid droplet accumulation both in vitro and in vivo. We used an in vitro cellular model to investigate whether an HCV core protein with residues specific to genotype 3 increased this phenomenon. Methods: Sequence comparisons for HCV core protein domain II, which is known to interact with lipid droplets, identified the phenylalanine (F) residue at position 164 as the only residue specific to genotype 3. We compared the area covered by lipid droplets in sections of cells producing a wild-type genotype 1a HCV core protein with that in cells producing a Y164F mutant protein. Results: Cumulative lipid droplet area was significantly greater in sections of cells producing the Y164F mutant HCV core protein than in cells producing the wild-type protein (p<0.001). The frequency of cell sections containing more than 3 μm2 of lipid droplets, in particular, was higher for the mutant than for the wild-type protein. Conclusion: Our data provide a molecular explanation for HCV genotype 3-specific lipid accumulation. This difference between genotypes may be due to phenylalanine having a higher affinity for lipids than tyrosine (Y). These observations provide useful information for further studies of the mechanisms involved in HCV-induced steatosis

Identification, simulation et effets des dépenses de transport dans une politique urbaine. Première phase : élaboration d'une grille fonctionnelle d'analyse des dépenses de transport urbain

Dans la réponse à l'appel d'idées du Secrétariat Permanent du Plan Urbain, les participants à cette recherche, à savoir l'INRETS, le LET et la ville de Mâcon, ont proposé l'élaboration d'un outil de suivi et d'évaluation des dépenses qu'une collectivité locale consacre à la fonction transport public. La réalisation d'un tel outil suppose que l'on est mesure de préciser la nature des flux de dépenses et leurs relations, mais aussi que l'on puisse caractériser les efforts d'amélioration du système de transport urbains, afin de définir les critères par rapport auxquels une évaluation peut être conduite. De telles évaluations ne peuvent se faire sur une seule année, non seulement du fait du phasage des réalisations, mais aussi du fait de l'induction de certaines dépenses (notamment en fonctionnement) sur les années suivant la réalisation. Ce premier rapport concerne la première phase de la recherche. Il présentera successivement l'intérêt d'un tel suivi et la structure du cadre proposé, les difficultés méthodologiques rencontrées au niveau de la connaissance des coûts, de la caractérisation des aménagements et de réalisation d'une telle base de données. Enfin seront discutées les limites du travail réalisé et les orientations retenues pour la deuxième phase.transport urbain ; gestion de la voirie urbaine ; infrastructure de transport ; évaluation des dépenses ; analyse des coûts ; dépenses collectivité locale ; Mâcon (Fr.) ; grille d'analyse des dépenses