Trace anomaly of the conformal gauge field

The proposed by Bastianelli and van Nieuwenhuizen new method of calculations of trace anomalies is applied in the conformal gauge field case. The result is then reproduced by the heat equation method. An error in previous calculation is corrected. It is pointed out that the introducing gauge symmetries into a given system by a field-enlarging transformation can result in unexpected quantum effects even for trivial configurations.Comment: 9 pages, LaTeX file, BI-TP 93/3

Plouhinec – Site de Menez-Dregan I

La fouille du gisement de Menez-Dregan 1 à Plouhinec (29) s’est poursuivie cette année sous la direction de Jean-Laurent Monnier (UMR 6566 du CNRS) et sous la conduite de Stéphan Hinguant (Afan). Rappelons ici qu’il s’agit d’un habitat en grotte attribué au Paléolithique inférieur dont la fouille depuis 1991 a montré toute l’importance sur le plan chronostratigraphique et paléoenvironnemental ainsi que sur l’étude techno-typologique des industries lithiques. La stratigraphie présente trois ni..

Intérêts d'une supplémentation en acide docosahexaénoïque dans la neuropathie diabétique

AIX-MARSEILLE2-BU Méd/Odontol. (130552103) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Evaluation du statut nutritionnel post-sleeve gastrectomie sur une cohorte de 161 patients (résultats à 12 et 24 mois)

AIX-MARSEILLE2-BU Méd/Odontol. (130552103) / SudocSudocFranceF

Le « colombanien » : un faciès régional du paléolithique inférieur sur le littoral armoricano-atlantique

ABSTRACT During the second part of the Middle Pleistocene, two distinct groups, belonging to the Lower Palaeolithic, are present in the western armorican region : a rather classic Acheulean and the archaic Colomba- nian, which contacts are still badly known. The Colombanian is characterized by "heavy stone tools" mainly composed of choppers, associated to "thin tools" with dominant notches and denticulates. Key-words: Middle Pleistocene, Lower Palaeolithic, Colombanian, choppers.RÉSUMÉ Au cours de la seconde moitié du Pleistocene moyen se sont développés, dans l'ouest armoricain, deux groupes distincts appartenant au Paléolithique inférieur, dont les rapports sont encore mal connus : un acheu- léen assez classique et le Colomba- nien à caractères archaïques. Le Co- lombanien est caractérisé par un « outillage lourd » composé principalement de choppers, associé à un « outillage léger » dominé par les encoches et les denticulés. Mots-clés : Pleistocene moyen, Paléolithique inférieur, Colombanien, choppers.Monnier Jean-Laurent, Molines Nathalie. Le « colombanien » : un faciès régional du paléolithique inférieur sur le littoral armoricano-atlantique. In: Bulletin de la Société préhistorique française, tome 90, n°4, 1993. pp. 283-294

Le site paléolithique inférieur de Raguénés (Névez, Finistère). Cadre géologique et industrie

An industry, only made from quartz, was found at Névez (Finistère), at several points of the cliff along the beach and small island of Raguénés. The preservation of the archaeological site could be associated with a fossil bay filled with sédiments, which is pronounced behind the coast by a topographie basin and an old cliff. The archaeological layer is associated with pleistocene beach remains and with a head covering the bedrock. The homogeneity of the flaked tools, as for their external aspect, and like their techno-typological characteristics, supposes one only human occupation attributed to the Lower Palaeolithic. As an hypothesis and referring to the south-armoricain stratigraphie context, an age corresponding to the isotopic stages 9 ou 11 is proposed.Une industrie exclusivement en quartz a été découverte sur la commune de Névez (Finistère) en plusieurs points de la falaise bordant la plage et l'îlot de Raguénés. La conservation du gisement pourrait être liée à une ancienne anse colmatée qui se marque dans l 'arrière-côte par une dépression topographique et une petite falaise morte. Le niveau archéologique est associé à des restes de plage ancienne et à un head recouvrant le substratum de micaschistes. L'homogénéité des pièces taillées, quant à leur état de surface, comme à leurs caractères techno-typologiques, plaide en faveur d'une unique occupation attribuée au Paléolithique inférieur. A titre d'hypothèse et par référence au contexte stratigraphique sud armoricain, un âge correspondant aux stades isotopiques 9 ou 11 est proposé.Molines Nathalie, Gageonnet Robert, Monnier Jean Laurent. Le site paléolithique inférieur de Raguénés (Névez, Finistère). Cadre géologique et industrie. In: Revue archéologique de l'ouest, tome 15, 1998. pp. 5-14

Stability constraints for oceanic numerical models: implications for the formulation of space-time discretizations

International audienceThanks to advances in computational power, global climate models are now configured with increasingly higher horizontal/vertical resolution. The extension of the range of application of this type of model, originally developed for low-resolution large-scale configurations, raises some new challenges of numerical nature. Indeed, depending on the target application, the numerics must be adapted based on accuracy, stability and efficiency considerations. To help rationalizing the appropriate choices for a given horizontal/vertical resolution, we developed offline diagnostics to predict stability limits associated with internal gravity waves, advection, diffusion, Coriolis, and bottom drag. This suite of diagnostics is applied to a set of numerical simulations with several horizontal/vertical resolutions and different numerical models including the global NEMO ORCA 1/2◦, 1/4◦ and 1/12◦, and the regional North-East Atlantic 1/36◦ MARS3D and NEMO configurations. Based on those results, we review the stability and accuracy of existing numerical kernels in vogue in the ocean community for advective processes and the dynamics of internal waves. We emphasize the additional value of studying the numerical kernel of ocean models in the light of coupled space-time approaches (e.g.; Daru & Tenaud 2004) instead of studying the time schemes independently from spatial discretizations, as usually done (e.g.; Shchepetkin & McWilliams, 2005), to get a more accurate measure of the stability and numerical diffusion of a given model

Comparing surface atmospheric variables from ERA40 and CORE as drivers of OGCMs for the period 1958 to 2004

International audienc

Intrinsic and Atmospherically Forced Variability of the AMOC: Insights from a Large-Ensemble Ocean Hindcast

International audienc

The mesoscale variability in the Caribbean Sea. Part I: Simulations and characteristics with an embedded model

International audienceThe variability in the Caribbean Sea is investigated using high resolution (1/15°) general circulation model experiments. For the first time in this region, simulations were carried out with a 2-way nested configuration of the NEMO primitive equation model. A coarse North Atlantic grid (1/3°) reproduces the main features of the North Atlantic and Equatorial circulation capable of influencing ocean dynamics in the Caribbean Sea. This numerical study highlights strong dynamical differences among basins and modifies the view that dynamics are homogeneous over the whole Caribbean Basin. The Caribbean mean flow is shown to organize in two intense jets flowing westward along the northern and southern boundaries of the Venezuela Basin, which merge in the center of the Colombia Basin. Diagnostics of model outputs show that width, depth and strength of baroclinic eddies increase westward from the Lesser Antilles to the Colombia Basin. The widening and strengthening to the west is consistent with altimetry data and drifter observations. Although influenced by the circulation in the Colombia Basin, the variability in the Cayman Basin (which also presents a westward growth from the Chibcha Channel) is deeper and less energetic than the variability in the Colombia/Venezuela Basins. Main frequency peaks for the mesoscale variability present a westward shift, from roughly 50 days near the Lesser Antilles to 100 days in the Cayman Basin, which is associated with growth and merging of eddies