Database of pleistocene periglacial featuresin France: description of the online version

A database of Pleistocene periglacial features in France has been compiled from a review of academic literature and reports of rescue archaeology, the analysis of aerial photographs and new field surveys. Polygons, soil stripes, ice-wedge pseudomorphs, sand wedges and composite wedge pseudomorphs are included in the database together with their geographic coordinates, geological context, description and associated references. It is hoped that this database, which aim is to be integrated in broader studies, will stimulate further work on past permafrost reconstruction and will favour greater understanding of the climatic events that lead to the formation of the periglacial features. The database is available online on the AFEQ-CNF INQUA website (https://afeqeng.hypotheses.org/487). A folder that contains photographs and sketches of the features is also available on request.Une base de données des structures périglaciaires pléistocènes de France a été créée à partir d’une revue de la littérature scientifique, de rapports d’archéologie préventive, de l’analyse de photographies aériennes et de nouvelles prospections de terrain. Les polygones, les sols striés, les pseudomorphoses de coin de glace, les coins de sable et les pseudomorphoses de coin composite ont été répertoriés dans la base de données avec leurs coordonnées géographiques, le contexte géologique, leur description et les références bibliographiques associées. Nous espérons que cette base de données, dont le but est d’être intégrée dans des études plus larges, stimulera de prochains travaux sur la reconstitution du pergélisol pléistocène et favorisera une plus grande compréhension des événements climatiques qui ont conduit à la formation de ces structures périglaciaires. La base de données est disponible en ligne sur le site de l’AFEQ-CNF INQUA (https://afeqeng.hypotheses.org/487). Un dossier contenant les photographies et dessins des structures périglaciaires est également disponible sur demande

Integration of the End Cap TEC+ of the CMS Silicon Strip Tracker

The silicon strip tracker of the CMS experiment has been completed and inserted into the CMS detector in late 2007. The largest sub-system of the tracker is its end cap system, comprising two large end caps (TEC) each containing 3200 silicon strip modules. To ease construction, the end caps feature a modular design: groups of about 20 silicon modules are placed on sub-assemblies called petals and these self-contained elements are then mounted into the TEC support structures. Each end cap consists of 144 petals, and the insertion of these petals into the end cap structure is referred to as TEC integration. The two end caps were integrated independently in Aachen (TEC+) and at CERN (TEC--). This note deals with the integration of TEC+, describing procedures for end cap integration and for quality control during testing of integrated sections of the end cap and presenting results from the testing

Reception Test of Petals for the End Cap TEC+ of the CMS Silicon Strip Tracker

The silicon strip tracker of the CMS experiment has been completed and was inserted into the CMS detector in late 2007. The largest sub system of the tracker are its end caps, comprising two large end caps (TEC) each containing 3200 silicon strip modules. To ease construction, the end caps feature a modular design: groups of about 20 silicon modules are placed on sub-assemblies called petals and these self-contained elements are then mounted onto the TEC support structures. Each end cap consists of 144 such petals, which were built and fully qualified by several institutes across Europe. Fro

De Narbonne à León, les singularités d’un trajet de l’Itinéraire d’Antonin

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La voie romaine "directe" de Dax à Bordeaux : nouvelles recherches

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Routes protohistoriques, romaines et médiévales d’Aquitaine : nouvelles approches, nouveaux résultats

Using the world in ancient societies : processes and forms of appropriation of space in Long Tim

High-power diode-pumped Q-switched Er3+:YAG single-crystal fiber laser

We describe an efficient laser emission from a directly grown Er3+:YAG single-crystal fiber that is resonantly pumped using a continuous-wave (CW) laser diode at 1532 nm. In a longitudinal pumping, it emits 12.5 W at 1645 nm with a slope efficiency of 32%, which is the highest ever reported for a directly grown Er:YAG single-crystal fiber laser. Using an off-axis pumping scheme, CW output powers up to 7.3 W can be reached and in Q-switched operation, the laser produces 2 mJ pulses with a duration of 38 ns at the repetition rate of 1 kHz with an M² factor below 1.8. To our knowledge this is the first directly grown Er3+:YAG single-crystal fiber Q-switched laser.Igor Martial, Julien Didierjean, Nicolas Aubry, François Balembois, and Patrick George

Guide archéologique de l’Aquitaine. De l’Aquitaine celtique à l’Aquitaine romane (VIe siècle av. J.-C. – XIe siècle ap. J.-C.)

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Adenine Binding Mode Is a Key Factor in Triggering the Early Release of NADH in Coenzyme A-dependent Methylmalonate Semialdehyde Dehydrogenase

International audienceStructural dynamics associated with cofactor binding have been shown to play key roles in the catalytic mechanism of hydrolytic NAD(P)-dependent aldehyde dehydrogenases (ALDH). By contrast, no information is available for their CoA-dependent counterparts. We present here the first crystal structure of a CoA-dependent ALDH. The structure of the methylmalonate semialdehyde dehydrogenase (MSDH) from Bacillus subtilis in binary complex with NAD+ shows that, in contrast to what is observed for hydrolytic ALDHs, the nicotinamide ring is well defined in the electron density due to direct and H2O-mediated hydrogen bonds with the carboxamide. The structure also reveals that a conformational isomerization of the NMNH is possible in MSDH, as shown for hydrolytic ALDHs. Finally, the adenine ring is substantially more solvent-exposed, a result that could be explained by the presence of a Val residue at position 229 in helix αF that reduces the depth of the binding pocket and the absence of Gly-225 at the N-terminal end of helix αF. Substitution of glycine for Val-229 and/or insertion of a glycine residue at position 225 resulted in a significant decrease of the rate constant associated with the dissociation of NADH from the NADH/thioacylenzyme complex, thus demonstrating that the weaker stabilization of the adenine ring is a key factor in triggering the early NADH release in the MSDH-catalyzed reaction. This study provides for the first time structural insights into the mechanism whereby the cofactor binding mode is responsible at least in part for the different kinetic behaviors of the hydrolytic and CoA-dependent ALDHs