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The southwestern Atlantic Ocean has one of the largest and most productive continental shelves of the southern hemisphere. Despite its relevance, its circulation patterns have been largely inferred from hydrographic observations and numerical models. Here we describe the variability of the shelf circulation based on the analysis of 11 months of multilevel currents measured by two bottom‐mounted acoustic Doppler current profilers deployed over the continental shelf at 39°S. The record‐length mean is 12 and 13 cm/s in the upper layer and decreases to 6 and 8 cm/s near the bottom, at the deployment nearer and further from the coast, respectively. The mean flow direction is toward the NE, following the orientation of the isobaths. Measurements at both sites show that the alongshore barotropic component accounts for 83% of the variability observed and are well correlated (0.86), suggesting a relatively uniform flow, which is presumably driven by large‐scale forcing. Indeed, large‐scale wind stress patterns dominate the temporal variability of the in situ currents and the passage of atmospheric fronts induces significant changes in the observed currents at all depths. We found that for 12% of the measurements the currents reverse the direction to the SW in response to these atmospheric patterns. Furthermore, the analysis of sea surface height reconstructed from bottom pressure measurements at both sites and from a coastal tide gauge reveals that the variability of the alongshore currents is driven by the cross‐shore pressure gradients generated by the alongshore wind stress. Eleven months of in situ velocities at two sites of the Argentine continental shelf are analyzedThe barotropic component explains 83% of the total variance and the alongshore velocities at the two sites are highly correlated (0.86)Alongshore wind stress causes across‐shore pressure gradients that modify the alongshore currents

An up‐to‐date map of the Antarctic Circumpolar Current (ACC) fronts is constructed from the latest version of mean dynamic topography (MDT) from satellite altimetry and reveals the narrowest ACC width in the Udintsev Fracture Zone (UFZ), with the strongest concentration of the three major ACC fronts within a limited distance as short as 170 km, about 40% narrower than that at Drake Passage. At 144°W, at the entrance of the UFZ, which lies between the Pacific‐Antarctic Ridge (PAR) and its eastwardly offset segment (offset PAR segment), there is a triple confluence of the Subantarctic Front, Polar Front, and Southern ACC Front . Downstream of this longitude, the Subantarctic Front progressively meanders northward over the relatively shallow offset PAR segment before channeling through the Eltanin Fracture Zone, thus diverging from the Polar Front which proceeds through the UFZ. In situ observations from two recent cruises at 144°W confirm the satellite altimetry‐derived frontal circulation in the UFZ region and yield a baroclinic transport relative to the bottom of 113 × 106m3/s, comparable to that through Drake Passage. The hydrographic sections show no Antarctic bottom water colder than 0.2 °C. Characteristics of major water masses are described, and the implications for their potential downstream modifications at Drake Passage are discussed in terms of the meridional overturning circulation across the ACC. Mesoscale eddy activity with periods shorter than 90 days is predominantly concentrated in the immediate downstream area of the offset PAR segment, suggesting a substantial poleward eddy heat flux there. The Antarctic Circumpolar Current is only 170 km wide in the Udintsev Fracture Zone, forming the narrowest circumpolar choke pointFirst observations of high‐quality hydrography in the Udintsev Fracture Zone show no Antarctic bottom water colder than 0.2 °CThe Udintsev Fracture Zone is a suitable site for a long‐term monitoring of the Antarctic Circumpolar Current

AbstractThe tarnished plant bug, Lygus lineolaris(Palisot de Beauvois) (Hemiptera: Miridae), causes severe damages in strawberry (Fragaria× ananassaDuchesne exRozier; Rosaceae) fields in Québec, Canada. Currently, only chemical insecticides successfully control that major pest. Lygus lineolarisaggregate in trap crops such as buckwheat (Fagopyrum esculentumMoench; Polygonaceae) and white mustard (Sinapis albaLinnaeus; Brassicaceae) but do not remain long enough on these plants to significantly reduce damages on strawberries. However, the attractiveness of the trap crop gives the opportunity to gather L. lineolarisin an area of the field where chemical treatments could be applied more efficiently. The aim of this study was to test the effectiveness of the combination of trap crop (buckwheat and white mustard) and chemical treatments to control L. lineolaris. Randomised complete-block design included treatment with either no trap crop, buckwheat, or white mustard row planted close to strawberry plants. Half blocks were treated with insecticide (cypermethrin) sprayed on strawberry plants (in treatment without trap crop) or directly on trap crop. We found that L. lineolariswas more abundant on buckwheat than on white mustard or strawberry plants. Insecticide application on trap crops reduced the population on these hosts, but did not reduce L. lineolarison adjacent strawberry plants. Behavioural avoidance and physiological pesticide resistance could explain this result.

Évaluer les indications du scanner dans la pratique médico-légale en 2021 et 2022 à l’Institut médico-légal de Paris (IMLP).

Les études antérieures sur la mucormycose du système nerveux central (SNC) sont basées sur des cas rapportés ou des cohortes de petits effectifs. Elles manquent de données cliniques et biologiques précises. Des études supplémentaires sont nécessaires pour guider les cliniciens, car la mucormycose du SNC nécessite un diagnostic rapide.

Current knowledge of the Earth's gravity field and its geoid, as derived from various observing techniques and sources, is incomplete. Within a reasonable time, substantial improvement will come by exploiting new approaches based on spaceborne gravity observation. Among these, the European Space Agency (ESA) Gravity field and steady-state Ocean Circulation Explorer (GOCE) satellite mission concept has been conceived and designed taking into account multi-disciplinary research objectives in solid Earth physics, oceanography and geodesy. Based on the unique capability of a gravity gradiometer combined with satellite-to-satellite high-low tracking techniques, an accurate and detailed global model of the Earth's gravity field and its corresponding geoid will be recovered. The importance of this is demonstrated by a series of realistic simulation experiments. In particular, the quantitative impact of the new and accurate gravity field and geoid is examined in studies of tectonic composition and motion, Glaciological Isostatic Adjustment, ocean mesoscale variability, water mass transport, and unification of height systems. Improved knowledge in each of these fields will also ensure the accumulation of new understanding of past and present sea-level changes.

Histamine diffusion from various o/w creams containing different emulsifiers was studied. To confirm the diffusion study, possible drug-emulsifier interactions were studied by dialysis of their aqueous solutions. Interaction between histamine and anionic sodium laurylsulphate resulted in the absence of free diffusible histamine. No interaction was observed with the non-ionic cetomacrogol. Repulsion by the cationic cetrimide increased histamine diffusion rate and total diffusing amount because distribution occurred in accordance with the Donnan membrane equilibrium.

The finite element ocean tide model of Le Provost and Vincent (1986) has been applied to the simulation of the M2 and K1 components over the South Atlantic Ocean. The discretisation of the domain, of the order of 200 km over the deep ocean, is refined down to 15 km along the coasts, such refinement enables wave propagation and damping over the continental shelves to be correctly solved. The marine boundary conditions, from Dakar to Natal, through the Drake passage and from South Africa to Antarctica, are deduced from in situ data and from Schwiderski’s solution and then optimised following a procedure previously developed by the authors. The solutions presented are in very good agreement with in situ data: the root mean square deviations from a standard subset of 13 pelagic stations are 1.4 cm for M2 and 0.45 cm for K1, which is significantly better overall than solutions published to date in the literature. Zooms of the M2 solution are presented for the Falkland Archipelago, the Weddell Sea and the Patagonian Shelf. The first zoom allows detailing of the tidal structure around the Falklands and its interpretation in terms of a stationary trapped Kelvin wave system. The second zoom, over the Weddell Sea, reveals for the first time what must be the tidal signal under the permanent ice shelf and gives a solution over that sea which is generally in agreement with observations. The third zoom is over the complex Patagonian Shelf. This zoom illustrates the ability of the model to simulate the tides, even over this area, with a surprising level of realism, following purely hydrodynamic modelling procedures, within a global ocean tide model. Maps of maximum associated tidal currents are also given, as a first illustration of a by-product of these simulations.

An upgraded version of the tidal solutions (FES94.1) is presented, obtained by assimilating an altimeter‐derived data set in the finite element hydrodynamic model, following the representer approach. The assimilated data are drawn from the CSR2.0 Texas solutions sampled on a 5° × 5° grid. The assimilation is applied over the Atlantic, Indian, and Pacific Oceans. The standard release of the new FES95.2 solutions is a 0.5° × 0.5° gridded version of the full finite element solutions. The associated tidal prediction model includes 26 constituents. The eight major constituents are drawn directly from the hydrodynamic model: K1, O1, Q1, M2, S2, N2, K2, and 2N2, corrected by assimilation except K2and 2N2. The other 18 constituents are derived by admittance. Among them are μ2, ν2, L2, T2, M1, P1, J1, and OO1. The quality of these solutions is evaluated by reference to a standard sea truth data set of 95 stations. This quality is significantly improved after the assimilation process is applied: the root‐sum‐square (RSS) of the differences between solutions and observations, for the eight major constituents, is reduced from 3.8 cm for FES94.1 to 2.8 cm for FES95.2, i.e., a gain of 1 cm. The performances of the prediction model are evaluated by comparing tidal predictions with observations at 59 sites distributed over the world ocean and by looking at the level of variance of the sea surface variability observed by the T/P altimeter at its cross‐over track points after tidal correction. These evaluations lead to the same conclusion: this new prediction model performs much better than the one based on FES94.1, because of correction of the major constituents by T/P data assimilation and because of the increase in the number of constituents from 13 to 26. The tidal predictions are at the level of accuracy of those produced by the best recent T/P empirical models.

La vasculopathie cérébrale drépanocytaire se caractérise par une occlusion progressive des artères cérébrales et le développement de collatérales pour maintenir le débit sanguin cérébral. Nous avons évalué la prévalence et la signification des hyperintensités vasculaires en 3D T1 écho de spin rapide (FSE) après injection de chélates de gadolinium dans la vasculopathie cérébrale drépanocytaire.

La perfusion par marquage de spins artériel (ASL) est une technique d’IRM de perfusion non invasive prometteuse. Son application dans la vasculopathie cérébrale drépanocytaire reste néanmoins limité du fait de temps de transit artériel (TTA) allongés par le développement de nombreuses collatérales. L’ASL avec délais post-marquage multiples (ASL multi-délais) semble prometteuse dans cette indication. Notre objectif était de valider la technique d’ASL multi-délais pour la mesure du débit sanguin cérébral chez des patients drépanocytaires avec vasculopathie cérébrale.

Le traitement du cancer médullaire de la thyroïde (CMT) présente des difficultés. Seuls 40 à 60 % des patients atteints sont guéris après thyroïdectomie. Après on a le choix entre la surveillance et des traitements avec effets indésirables parfois graves sans bénéfice démontré sur la survie des patients. Nous avons montré que deux anti-inflammatoires non stéroïdiens (AINS), le célécoxib et l’indométacine d’usage courant et pouvant être utilisé sur de longue périodes ralentissent significativement la division cellulaire dans un modèle de CMT induit par injection de cellules TT humaines chez la souris nude. L’objectif du travail était d’amplifier l’effet anti-tumoral par adjonction de monoxyde d’azote (NO) à ces deux AINS.