Les ombres de Pétersbourg

Et lentement nous abandonnent les ombres que nous n’appelons plus, dont le retour nous aurait même été effrayant.Anna Akhmatova, Les élégies du nord 3 janvier Le samedi 3 janvier 2009, les trottoirs gelés de Saint-Pétersbourg lancent de brefs éclats sous le soleil matinal. La température a chuté de dix degrés dans la nuit. Tout est figé, glacial, désert. Les avenues dessinent de vastes perspectives impeccable­ment vides, comme sur les photos de Gabriele Basilico, ou certaines rues de Kyôto l’..

Défamiliarisation

Tout cela, au fond, pourrait n’être qu’une affaire de généalogie : deux arrière-grands- pères navigateurs, l’un des deux fils de paysan, jeté en pleine mer comme par hasard, et pour fort peu de temps car mort à moins de quarante ans, l’autre rejeton d’une longue lignée de marins, mousse parti en Patagonie à douze ans, puis commandant dans la Marine Marchande, ayant fait plusieurs fois le tour du monde, du Chili au Japon, de Singapour à Panama, deux ancêtres ayant vu du pays, comme on dit, fig..

International Olympic Committee consensus statement on pain management in elite athletes

Pain is a common problem among elite athletes and is frequently associated with sport injury. Both pain and injury interfere with the performance of elite athletes. There are currently no evidence-based or consensus-based guidelines for the management of pain in elite athletes. Typically, pain management consists of the provision of analgesics, rest and physical therapy. More appropriately, a treatment strategy should address all contributors to pain including underlying pathophysiology, biomechanical abnormalities and psychosocial issues, and should employ therapies providing optimal benefit and minimal harm. To advance the development of a more standardised, evidence-informed approach to pain management in elite athletes, an IOC Consensus Group critically evaluated the current state of the science and practice of pain management in sport and prepared recommendations for a more unified approach to this important topic

Caractéristiques des malformations artérioveineuses cérébrales révélées par des crises d'épilepsie

PARIS7-Xavier Bichat (751182101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Biopolymer hydrolysis and bacterial production under ambient hydrostatic pressure through a 2000 m water column in the NW Mediterranean

International audienceKinetic parameters for aminopeptidase, phosphatase, and bacterial production rates were studied during spring and fall through a 2000 m water column in the NW Mediterranean. Bacterial production ranged from 60.4 ng at 30 m to 0.2 ng C l -1 h -1 at 2000 m. For both ectoenzymatic activities, the Km values ranged from 0.44 to 1.13 μM for aminopeptidase activity and from 0.05 to 1.23 μM for phosphatase activity. Depth profiles of the potential activity of aminopeptidase and phosphatase activity drastically decreased below depths of 100 m. At 1000 m, hydrolytic activities were one order of magnitude lower than the maximal rate measured in the surface layer. Despite this decrease, depth-integrated rates through the thickness of different water masses showed that the potential hydrolysis fluxes within the productive surface layer (10-200 m), through the twilight zone (200-1000 m depth), and through the deep water mass (1000-2000 m) were roughly the same order of magnitude. This study used the first assay for measuring ectoenzymatic activities of deep-sea microbial populations where pressure stresses were eliminated during sampling and incubation. The results showed that prokaryotic induced ectoenzymatic activities are affected by pressure conditions. Generally, aminopeptidase and phosphatase rates measured in samples maintained under in situ pressure conditions were 2.3 times higher than those measured in their decompressed counterparts

Pressure effects on surface Mediterranean prokaryotes and biogenic silica dissolution during a diatom sinking experiment

International audienceThis study examined the effect of increasing pressure on biogenic silica dissolution and on prokaryotic assemblages associated with diatom detritus. Experiments were carried out in hyperbaric bottles subjected to a gradual increase in pressure and compared to incubations at atmospheric pressure. To examine only pressure effects and to simulate detritus degradation in the Mediterranean Sea, the incubation temperature was kept constant (13°C), while pressure was increased by 1.5 MPa d-1, simulating a fall of particles at a sinking rate of 150 m d-1 over 8 d. Aminopeptidase activity was significantly lower (nearly 5-fold) under increasing pressure than under atmospheric pressure conditions. Lower aminopeptidase activity under increasing pressure affected biogenic silica dissolution, at least at the beginning of the incubation, corresponding to a simulated depth of the first 800 m of the water column. Silicic acid regeneration rates were very low (0.07 ± 0.02 μmol l-1 h-1) under increasing pressure conditions during the first 4 d (i.e. between 200 and 800 m), while rates were much higher under atmospheric pressure (0.32 ± 0.05 μmol l-1 h-1). However, orthosilicic acid concentrations in the incubations under increasing pressure approached those of the atmospheric pressure incubations by the end of the experiment. In contrast, the taxonomic composition of prokaryotic communities was not affected by increasing pressure, but the input of fresh diatom detritus led to an increase in the relative abundance of the Cytophago-Flavobacter cluster and γ-Proteobacteria. These results suggest that hydrostatic pressure affects the function rather than the broad taxonomic structure of prokaryotic communities associated with sinking detrital particles

Chapitre VIII. Dynamique fluviale holocène de la Loire moyenne (val d’Orléans, France)

Introduction La gestion du risque fluvial actuel et futur nécessite une bonne compréhension de la complexité de la réponse fluviale aux changements du climat et de l’occupation du bassin-versant par les sociétés. Dans le contexte actuel de changement global, les reconstitutions des dynamiques fluviales, survenues durant le passé en réponse aux changements climatiques et sociaux, constituent des clés pour une meilleure perception des dynamiques actuelles et futures (Gregory et al., 2006). Les ..

Chapter 8. Holocene fluvial dynamics of the middle Loire River (Val d’Orléans, France)

Introduction Current and future fluvial risk management requires a good understanding of the complexity of fluvial responses to climate and societal changes. In the current context of global change, the reconstruction of fluvial dynamics in response to climate and societal changes during the past, are key for a better perception of current and future dynamics (Gregory et al., 2006). During the last few decades, several works on European catchments have revealed important variability in fluvia..