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Arctic seabirds exposed to acute stress display state- and environment-dependent patterns of surface temperature change, independent of mercury contamination
No full textInternational audienc
Mercury concentrations, habitat and trophic position of Antimora rostrata and Macrourus holotrachys from South Georgia (Southern Ocean)
No full textInternational audienceMercury (Hg) is a neurotoxic element that can harm marine wildlife. Hg can reach the Southern Ocean through atmospheric and oceanic currents. However, data on Hg in Southern Ocean deep-sea fishes remain scarce. Our study assessed the influence of biological and ecological factors on Hg bioaccumulation in two deep-sea species, blue antimora (Antimora rostrata) and bigeye grenadier (Macrourus holotrachys), inhabiting the South Georgia region. Specifically, we aimed to: 1) analyse the habitat and trophic position of both species; 2) understand how Hg concentrations vary between tissues (muscle, brain, liver and gills); 3) evaluate how biological (length and weight) and ecological characteristics (trophic position (δ15N) and habitat (δ13C)) influence Hg concentrations. Muscle tissue had the highest Hg concentrations in both species, while the liver in A. rostrata and gills in M. holotrachys had the lowest. Overall, A. rostrata exhibited lower Hg concentrations (51.0 ± 9.0) than M. holotrachys (62.0 ± 11.0). No significant relationships were found between Hg concentrations and length, weight nor trophic position of A. rostrata. In contrast, M. holotrachys showed a positive relationship between Hg concentrations and habitat in all tissues, whereas for length and weight this positive relationship was observed in most tissues except the brain. A. rostrata is a pelagic feeder, whereas M. holotrachys mostly feeds near the sea bottom, highlighting how feeding strategy and habitat influence Hg bioaccumulation. It also reveals unexpectedpatterns of Hg distribution among tissues, particularly in the brain, where M. holotrachys exhibited one of thehighest Hg concentrations
Navigating unpredictable oceans: Mapping fine-scale temporal and spatial variability in little penguin foraging areas
No full textInternational audienceFaced with unpredictable prey in dynamic ecosystems, seabirds have developed strategies to efficiently locate food, particularly during breeding when time and space are constrained. Using 13 yr of GPS data from 422 little penguins Eudyptula minor, we tested whether they rely on consistent foraging areas to reduce search times or respond to dynamic environmental cues. Our results suggest a combination of these strategies, depending on the spatial scale.Little penguins used only 32% of the potential foraging range, concentrating in shallow waters within 70 km and mostly east of their colony, as confirmed by our spatial density models. However, finer-scale analyses using kriging maps showed no recurring foraging hotspots over 13 yr, suggesting high inter-annual variability in prey availability. Despite this variability, penguins consistently spent more time in the most productive areas and also exploited more areas with favourable environmental conditions to access prey (thermocline, current, waves), even as these conditions shifted within and across breeding seasons. In years of poor conditions, they foraged farther from the colony, resulting in lower breeding success. These results emphasise the adaptability of little penguins to dynamic environmental conditions, but underscore the vulnerability of their foraging and breeding success to oceanographic variability in a climate-impacted ecosystem
Aux origines de la sinologie française : étudier le chinois aux XVIIe et XVIIIe siècles en France
No full textActes de Colloque : The 5th International Symposium of the European Association of Chinese Teaching in celebration of the 10th Anniversary of the EAC
Object Recognition Using Deep Learning‐Powered Glove With Flex and MPU Sensors Fusion
No full textInternational audienceThe integration of multimodal sensor data is critical for developing intelligent systems capable of extracting complex, insightful information. We introduce a robust platform for high‐fidelity and real‐time hand posture replication, as well as object classification, centered on a novel tactile‐sensing glove. The glove design incorporates 10 flex sensors spanning the PIP and MCP joints, complemented by two MPU6050 IMUs strategically mounted on the thumb’s TM and the hand’s dorsal CMC bones for comprehensive motion capture. We leverage this rich sensory data to drive a digital twin—constructed in Blender and visualized in the Unity3D engine—achieving precise real‐time hand posture reproduction, necessary for visual feedback and sensor anomaly detection during sensor calibration and data collection by the operator. Furthermore, we evaluate the glove’s classification capability on a custom dataset of 15 objects. Through a grid search optimization, we trained One‐dimensional Convolutional Neural Network (CNN‐1D), Long‐Short Term Memory (LSTM), and Temporal Convolutional Network (TCN) architectures. The models achieved classification testing accuracies confidence intervals of [95.40%, 96.50%], [92.55%, 93.84%], and [93.47%, 94.76%], respectively, validating the high‐performance and utility of our multimodal sensing approach
HYPA-dao: Une lexico-didactique gestuelle pour apprendre toutes les syllabes du chinois mandarin
No full textInternational audienceCe manuel propose une lexico-didactique pour apprendre toutes les syllabes du chinois mandarin en s'aidant de la suite applicative des applications claviers HYPAkeyboard et du transcripteur HYPA proposé sur l'onglet "Lire" du site www.hypacosmos.com
Une modernisation longtemps ajournée : la construction du dock-entrepôt bordelais au XIXe siècle
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Les Voyageurs français en Chine aux XVIIe et XVIIIe siècles
No full textLes voyageurs français en Chineaux XVIIe et XVIIIe siècles, éditions l'Harmattan, collection Recherches Asiatiques, Paris, 2007Contrairement aux idées reçues, la rencontre de la France avecla Chine remonte à plus loin que ce qu’on imaginait. En effet,dès 1685, Louis XIV envoie en Chine six missionnaires jésuites,tous parés du titre ‘’Mathématiciens du Roi’’. Ceux-cis’introduisent à la Cour Impériale et découvrent peu à peu lalangue et la civilisation chinoises. Ils transmettent ainsi lestechniques et le savoir entre Versailles et le Palais Impérial. Cependant,si leur prosélytisme sous couvert d’aide scientifiquen’atteint pas les buts espérés, ces Pères deviennent les ‘’médiateursculturels’’ entre la France et la Chine. Si leurs connaissancessur l’Empire Céleste accumulées au fil des ans, puis transmises en France, éclaireront, au Siècle des Lumières, Montesquieu, Voltaire et bien d’autres, en revanche, il y avait assurément un fossé entre la Chine vue par les missionnaires et la Chine telle qu’elle était réellement. Découvrons donc, sans prétention à l’exhaustivité, à travers lestémoignages des Français du Siècle des Lumières, les caractéristiquespropres à nos deux civilisations au cours d’une époque charnière pour chacune d’elle. En Chine, comme en France, on assiste pendant cette époque aux derniers feux de l’Ancien Régime où jaillissent les premières étincelles d’un monde nouveau, qui, à travers un siècle et demi de bouleversements, allait devenir celui que nous connaissons actuellement
