[Whipple's disease: a curable encephalitis].

International audienceINTRODUCTION: Whipple's disease is a rare systemic infectious disorder. It may present with a wide range of clinical manifestations and therefore its diagnosis may be challenging. CASE REPORT: We report a 45-year-old man who presented with acute encephalitis related to Whipple's disease. Despite the negativity of the polymerase chain reaction (PCR) test in cerebrospinal fluid, diagnosis was obtained by histopathology, PCR tests and immunohistochemistry in multiple samples. The outcome with antibiotherapy was considered as "spectacular". CONCLUSION: Whipple's disease is a rare cause of encephalitis. Its diagnosis needs the confrontation of histology and PCR tests in multiple samples. The outcome with an adapted antibiotherapy may be very successful

Experimental investigation of the kinematics of post-impact ice fragments

International audienceHail is more hazardous for aircraft engines compared to rain and snow,mainly, because of its solid nature and high water content. In extreme cases it can lead to engine ame out. In order to avoid such situations, aero engines should be designed to withstand hail ingestion. For this purpose we have studied the post-impact characteristics of ice, such as particle velocity and directions of travel. To achieve this goal, a large experimental program has been undertaken, in which spherical ice specimens were projected against a rigid plate. Three specimen diameters (6.2, 12.9 and 27.5mm) and four impact angles (20, 45, 75 and 90 _) were considered, as well as a wide range of impact velocities (60-200m/s). From this experimental work, we can conclude that the ice fragments formed after impact do not bounce back and that the post-impact ice trajectory angle is lower than 2 _. This is in line with observations found in the literature. On the other hand, the ice fragments are mainly organised in a circular cloud, when observed in the Preprint submitted to International Journal of Impact Engineering February 21, 2011 target plane. The center of this cloud has the same velocity as the initial ice ball tangential impact velocity. Furthermore, the cloud radius expands with a rate proportional to the ice ball normal impact velocity. Finally, each fragment inside the cloud has a relative velocity which varies linearly with its distance from the cloud center. These experimental observations should be very helpful in developing models and simulations of hail ingestion by aircraft engines

Consequences of fluvial maintenance operations on the sediment morphodynamic and the associated BIOdiversity in the mosaic of Mareau-aux-prés islands

International audienc

Conséquences des travaux d'entretien du lit de la Loire sur la biodiversité au sein des iles de Mareau-aux-prés (Réserve Nationale de Saint-Mesmin) : principaux résultats après 5 années d’étude.

International audienc

Consequences of fluvial maintenance operations on the biodiversity and landscape in the Mareau-aux-Prés islands (National Reserve of Saint-Mesmin, Loire River, France)

International audienceThe Mareau-aux-Prés islands, along the Loire river are characterized by a multiple channel pattern, where natural limestone riffles influence the morphology and spatial distribution of vegetated islands and secondary channels. Within these islands, in september 2012, fluvial management operations (FMO) were launched. The vegetation of the central sandy-gravelly bar (3 ha area) was uprooted and the bar level lowered in order to maintain the flow capacity of the river. The FMO are equivalent to a natural important flood : a new bare mineral substrate has appeared and since spring 2013 followed the succession of geomorphic, pioneer and biogeomorphic phases in interactions between hydro-morphodynamics and Salicaceae vegetation.This sandy-gravelly bar is an ideal field support for studying long-term ecological issues. A multi-disciplinary research programme ('BioMareau' project) is currently being conducted from 2012 to 2019, focusing on interactions and feedbacks between biotic and abiotic components and, since 2017, on landscape evolution and perception

Five-year study of consequences of fluvial maintenance operations on the biodiversity in the Mareau-aux-Prés islands (National Reserve of Saint-Mesmin, Loire River, France)

National audienceThe Mareau-aux-Prés islands, along the Loire river, are characterized by a multiple channel pattern, where natural limestone riffles influence the morphology and spatial distribution of vegetated islands, secondary channels and alluvial bars. In September 2012, within these islands, the vegetation of the central 3 ha sandy-gravelly bar was uprooted and the bar level lowered in order to maintain the flow capacity of the river. A new sandy-gravelly bar appeared in spring 2013, ideal field support to study long-term ecological issues. A multidisciplinary research programme (‘BioMareau’ project) is currently being conducted from 2012 to 2019, focusing on physical and biological compartments. Field measurements on annual basis were performed on hydrosedimentary processes. Biotic components focus on colonization dynamics by Populus nigra seedlings (studying small-scale DNA spatial genetic structure and through plot survey), by native and invasive flora (through seed bank and summer inventories), by community assemblages of ground beetles Coleoptera Carabidae, by gravel nesting birds and on the consequence of the modification of the feeding habitat by the European beaver (as the island constituted the main source of wood). We will present 5 years of results after fluvial maintenance operations. The applied objectives of such study are to guide river managers in order to perform optimal useful management operations with a minimum loss of biodiversity.L’objectif de ce projet de recherche est d’étudier les conséquences des travaux d’entretien du lit de la Loire sur plusieurs composantes de la biodiversité d’un ilot au sein des 13 hectares des iles de Mareau-aux-prés (Loiret). Dans l’optique de maintenir la capacité d’écoulement du fleuve, le Pôle Loire (DDT du Loiret) a dévégétalisé et arasé cet ilot en septembre 2012. La biodiversité présente sur cet ilot a été ainsi remise à zéro. Mais la dynamique naturelle du fleuve a apporté de nouveaux sédiments lors de l’hiver suivant et une nouvelle biodiversité et un nouvel assemblage de communautés se sont installés de novo, à partir de flux de populations provenant des autres ilots et berges. Ce projet multidisciplinaire est centré sur cette nouvelle dynamique de recolonisation. Nous présentons ici les résultats 5 ans après travaux, sur la biodiversité intra et interspécifique (via l’acquisition de données in situ et d’analyses génétiques et spatialisées) autour de quatre communautés : végétation herbacée, arbustive et arborescente, autochtone et exotique ; avifaune nicheuse des grèves ; castor et entomofaune coléoptère Carabidae en couplant ces données avec celles de la morphodynamique fluviale, variable chaque année

Five years study of consequences of fluvial maintenance operations on the biodiversity in the Mareau-aux-Prés islands (Loire river, France)

International audienceThe Mareau-aux-Prés islands, along the Loire river are characterized by a multiple channel pattern, where natural limestone riffles influence the morphology and spatial distribution of vegetated islands, secondary channels and alluvial bars. Within these islands, in september 2012, the vegetation of the central 3 ha sandy-gravelly bar was uprooted and the bar level lowered in order to maintain the flow capacity of the river. A new sandy-gravelly bar appeared in spring 2013, ideal field support for studying long-term ecological issues. A multi-disciplinary research programme ('BioMareau'project) is currently being conducted from 2012 to 2019, focusing on biodiversity recolonization and on interactions and feedbacks between biotic and abiotic components

Conséquences des travaux d’entretien du lit de la Loire sur la biodiversité au sein des iles de Mareau-aux-prés (Réserve Naturelle Nationale de St-Mesmin) : principaux résultats après 5 années d’étude

L’objectif de ce projet de recherche est d’étudier les conséquences des travaux d’entretien du lit de la Loire sur plusieurs composantes de la biodiversité d’un ilot au sein des 13 hectares des iles de Mareau-aux-prés (Loiret). Dans l’optique de maintenir la capacité d’écoulement du fleuve, le Pôle Loire (DDT du Loiret) a dévégétalisé et arasé cet ilot en septembre 2012. La biodiversité présente sur cet ilot a été ainsi remise à zéro. Mais la dynamique naturelle du fleuve a apporté de nouveaux sédiments lors de l’hiver suivant et une nouvelle biodiversité et un nouvel assemblage de communautés se sont installés de novo, à partir de flux de populations provenant des autres ilots et berges. Ce projet multidisciplinaire est centré sur cette nouvelle dynamique de recolonisation. Nous présentons ici les résultats 5 ans après travaux, sur la biodiversité intra et interspécifique (via l’acquisition de données in situ et d’analyses génétiques et spatialisées) autour de quatre communautés : végétation herbacée, arbustive et arborescente, autochtone et exotique ; avifaune nicheuse des grèves ; castor et entomofaune coléoptère Carabidae en couplant ces données avec celles de la morphodynamique fluviale, variable chaque année.The Mareau-aux-Prés islands, along the Loire river, are characterized by a multiple channel pattern, where natural limestone riffles influence the morphology and spatial distribution of vegetated islands, secondary channels and alluvial bars. In September 2012, within these islands, the vegetation of the central 3 ha sandy-gravelly bar was uprooted and the bar level lowered in order to maintain the flow capacity of the river. A new sandy-gravelly bar appeared in spring 2013, ideal field support to study long-term ecological issues. A multidisciplinary research programme (‘BioMareau’ project) is currently being conducted from 2012 to 2019, focusing on physical and biological compartments. Field measurements on annual basis were performed on hydrosedimentary processes. Biotic components focus on colonization dynamics by Populus nigra seedlings (studying small-scale DNA spatial genetic structure and through plot survey), by native and invasive flora (through seed bank and summer inventories), by community assemblages of ground beetles Coleoptera Carabidae, by gravel nesting birds and on the consequence of the modification of the feeding habitat by the European beaver (as the island constituted the main source of wood). We will present 5 years of results after fluvial maintenance operations. The applied objectives of such study are to guide river managers in order to perform optimal useful management operations with a minimum loss of biodiversity