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The South Atlantic Meridional Overturning Circulation (SAMOC) observing system has evolved tremendously since 2007, and has substantially improved our understanding of the dynamics and variability of the upper, deep, and abyssal South Atlantic circulation from daily to interannual time-scales. However, the SAMOC daily time series derived from moored arrays are still relatively short and are only available at 11°S and 34.5°S. To expand the SAMOC time series in space and time, we derived monthly zonal trans-basin temperature (T) and salinity (S) sections since 1993 at four latitudes (20°S, 25°S, 30°S, and 34.5°S) based on historical relationships between T, S, and satellite sea level. The resulting meridional overturning circulation (MOC) and meridional heat transport (MHT) estimates at 20°S, 25°S, and 30°S are significantly correlated with each other at near zero lag, however correlations with the estimates at 34.5°S are somewhat lower. Although the overturning contribution dominates changes in the MHT at all four latitudes, the gyre contribution increases southward, reaching 30% of the explained MHT variability at 34.5°S. These 30-year monthly records indicate that the dominant mechanism controlling the MOC/MHT variability alternates between wind forcing and internal ocean dynamics. Therefore, both mechanisms must be monitored to fully capture changes in the MOC/MHT. These estimates demonstrate a linkage between the tropical Pacific forcing and heat content changes in the subtropical South Atlantic, as well as the impact of the MOC/MHT on extreme weather events, and provide context for measurements obtained from the SAMOC moored arrays., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The Taylor Energy Site is located in the vicinity of the Mississippi Delta region over the Northern Gulf of Mexico (NGoM). Surface oil patches have been persistently observed within this site since 2004, when an oil rig was destroyed by Hurricane Ivan. A multiplatform observational experiment was conducted in April 2017 to investigate, for the first time, the main hydrocarbon pathways from the Taylor Energy Site toward the NGoM continental shelves, and the Gulf interior, under the influence of local and regional physical processes. Results indicate that the Mississippi River (MR)‐induced fronts over the Taylor Energy Site, in combination with local circulation, prevailing winds and broader regional dynamics determine the hydrocarbon transport. The drifters deployed during the field experiment, in tandem with satellite data, drone imagery, wind measurements, and radar‐derived data, efficiently described three major hydrocarbon pathways, associated with MR plume dynamics (downstream/upstream coastal currents) and basin‐wide circulation (offshore pathway). Two different types of drifters, drogued and undrogued, showed clearly different pathways, which suggest potential differences in the expected advection of oil, depending on whether it forms a surface slick or whether it is partially mixed below the surface. The existence of multiple river fronts influenced the fate of oiled waters, preventing the hydrocarbons from reaching the Delta, like a natural boom barrier, trapping and directing the oil either westward or eastward. Thermohaline measurements showed that the MR plume near Taylor was 5–10 m deep, while the clearer ocean was characterized by a 40 m upper ocean homogenous layer.

International audience; Aims: The purpose of this study was to characterize OmpA, a major glycoprotein isolated from the membrane fraction of Flavobacterium psychrophilum, and to evaluate its potential as antigenic unit in a possible vaccine. Methods and Results: The expression product of ompA is a 465-amino-acid protein precursor that contains a 21-amino acid signal peptide and has overall homology (up to 60% identity) with similarly sized proteins of some bacteria belonging to the Flavobacteriaceae family. The carboxy-terminal region contains the ‘OmpA ⁄ MotB’ domain ⁄ signature and five putative ‘Thrombospondin type 3 repeats’ domains have been identified in the central region. OmpA was clearly detected in the outer membrane fraction and its surface exposure was demonstrated. OmpA is one of the immunodominant antigens and binding of specific anti-OmpA antibodies lead to cell lysis in the presence of complement. Fish immunized with OmpA emulsified with Freund’s adjuvant developed a high antibody titter. Conclusions: Collectively, the data obtained here indicate that OmpA may be involved in Fl. psychrophilum ⁄ host cell interactions and appears to be a potential immunogen for a vaccine. Significance and Impact of the Study: This study is one step in the direction of understanding pathogenesis of Fl. psychrophilum and development of future vaccine.

The amygdala involvement in fear processing has been reported in behavioral, electrophysiological, and functional imaging studies. However, the literature does not provide precise data on the temporal course of facial emotional processing. Intracranial event-related potentials to facial expressions were recorded in epileptic patients implanted with depth electrodes during a presurgical evaluation. Specific potentials to fear beginning 200 ms poststimulus were observed in amygdala, both individually in two patients and in a ten patient population study. These potentials occurred 100 ms earlier than potentials to disgust recorded in insula in a previous study. Potentials to fear were confined in amygdala during a first transient period and then, during a second period of sustained activity, spread to occipito-temporal, anterior temporal, and orbitofrontal cortex in two patients. This study clarifies the temporal course of the involvement of these structures known to be part of a neural network recruited to process emotional information.