VLTI status update: a decade of operations and beyond

We present the latest update of the European Southern Observatory's Very Large Telescope interferometer (VLTI). The operations of VLTI have greatly improved in the past years: reduction of the execution time; better offering of telescopes configurations; improvements on AMBER limiting magnitudes; study of polarization effects and control for single mode fibres; fringe tracking real time data, etc. We present some of these improvements and also quantify the operational improvements using a performance metric. We take the opportunity of the first decade of operations to reflect on the VLTI community which is analyzed quantitatively and qualitatively. Finally, we present briefly the preparatory work for the arrival of the second generation instruments GRAVITY and MATISSE.Comment: 10 pages, 7 figures, Proceedings of the SPIE, 9146-1

Mice Doubly-Deficient in Lysosomal Hexosaminidase A and Neuraminidase 4 Show Epileptic Crises and Rapid Neuronal Loss

Tay-Sachs disease is a severe lysosomal disorder caused by mutations in the HexA gene coding for the α-subunit of lysosomal β-hexosaminidase A, which converts GM2 to GM3 ganglioside. Hexa−/− mice, depleted of β-hexosaminidase A, remain asymptomatic to 1 year of age, because they catabolise GM2 ganglioside via a lysosomal sialidase into glycolipid GA2, which is further processed by β-hexosaminidase B to lactosyl-ceramide, thereby bypassing the β-hexosaminidase A defect. Since this bypass is not effective in humans, infantile Tay-Sachs disease is fatal in the first years of life. Previously, we identified a novel ganglioside metabolizing sialidase, Neu4, abundantly expressed in mouse brain neurons. Now we demonstrate that mice with targeted disruption of both Neu4 and Hexa genes (Neu4−/−;Hexa−/−) show epileptic seizures with 40% penetrance correlating with polyspike discharges on the cortical electrodes of the electroencephalogram. Single knockout Hexa−/− or Neu4−/− siblings do not show such symptoms. Further, double-knockout but not single-knockout mice have multiple degenerating neurons in the cortex and hippocampus and multiple layers of cortical neurons accumulating GM2 ganglioside. Together, our data suggest that the Neu4 block exacerbates the disease in Hexa−/− mice, indicating that Neu4 is a modifier gene in the mouse model of Tay-Sachs disease, reducing the disease severity through the metabolic bypass. However, while disease severity in the double mutant is increased, it is not profound suggesting that Neu4 is not the only sialidase contributing to the metabolic bypass in Hexa−/− mice

Actualités thérapeutiques dans le traitement du Syndrome de Détresse Respiratoire Aiguë

National audienceLa connaissance physiopathologique et épidémiologique du SDRA a progressé ces dernières années. Différentes pistes thérapeutiques ont été évaluées par des essais cliniques récents.Les médicaments supposés limiter l'inflammation pulmonaire et favoriser la résorption de l'œdème alvéolaire se sont montrés décevants. La corticothérapie (méthylprédnisolone) peut être intéressante à la phase aiguë du SDRA mais ne doit pas être utilisée au-delà des deux premières semaines. Les béta-2 mimétiques, malgré des données préliminaires prometteuses, se sont révélés inefficaces, voire délétères, sur les études prospectives randomisées. La limitation des apports liquidiens semble réduire la formation d'œdème et permet une amélioration des échanges gazeux et un moindre recours à la ventilation artificelle.Les progrès les plus probants ont été réalisés en développant des stratégies de ventilation protectrice réduisant le barotraumatisme et optimisant le recrutement alvéolaire. La ventilation non invasive au masque est peu recommandée en dehors des formes précoces peu hypoxiques. Les thérapeutiques complexes comme le décubitus ventral, la ventilation haute fréquence, le NO, ou les échanges gazeux extra-corporels restent des thérapeutiques d'exception dont l'efficacité et la place sont à préciser

Shape Optimization of a Compact Dual-mode Filter Using Bézier Curves Parametrization

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The Newborn Infant's Thermal Environment in the Delivery Room When Skin-to-Skin Care Has to Be Interrupted.

International audienceOBJECTIVE: Newborns are prone to hypothermia immediately following birth. Hypothermia is associated with increased morbidity and mortality rates. We sought to assess the thermal environment and metabolic costs associated with exposure to various situations in the delivery room when skin-to-skin care (SSC) has to be curtailed. METHODS: Environmental variables (air temperature: T(a); relative humidity: RH; radiative temperature: T(r); and air convection velocity) were recorded during sequences reproducing SSC, in the maternity unit's various rooms ("passive environments") and in incubators ("active environments"). Analytical calorimetry was then used to calculate the body heat loss (BHL) from these data. RESULTS: The analysis of 1280 measurements of T(a,) RH, T(r), and air convection velocity in SSC, passive and active environments revealed that (i) the thermohygrometric environment during SSC was optimal (T(a): 32.7\,±\,3.2\,° C; RH: 50.9\,±\,5.6%), (ii) BHL rose when SSC had to be interrupted, and (iii) the use of a radiant incubator prevented hypothermia and reduced dry BHL but not humid BHL (9.4\,±\,1.5\,kcal/kg/h; p\,<\,.001), relative to SSC (5.8\,±\,2.0\,kcal/kg/h; p\,<\,.001). CONCLUSION: The newborn infant's thermohygrometric environment is optimal during SSC in the delivery room. When SSC was interrupted, T(a) and RH always decreased, and BHL increased in all passive environments

alpha,omega-Bis(trialkoxysilyl) Telechelic Polyolefin/Polyether Copolymers for Adhesive Applications Using Ring-Opening Insertion Metathesis Polymerization Combined with a Chain-Transfer Agent

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MsrQ, the membrane bound flavocytochrome component of the methionine sulfoxide reductase system MsrPQ

International audienc

MsrQ, the membrane bound flavocytochrome component of the methionine sulfoxide reductase system MsrPQ

International audienc