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Asian geodynamics, climate and biodiversity
No full textInternational audienceThis book addresses the interplay between geodynamics, climate, and biodiversity, focusing on the India-Asia collision, the key abiotic parameter shaping the region's topography, climate, and ecosystems. Asia, with its unparalleled geological activity and rich biodiversity, is ideal for studying interactive processes of Earth System Science. Collision shaped the Himalayan and Tibetan Plateau regions, significantly influencing atmospheric circulation, precipitation patterns, and biotic evolution. Key questions revolve around the timing and mechanisms of these processes, which remain topics of debate. Fossil records highlight evolutionary patterns, such as plant and animal dispersals during tectonic shifts like the “Africa-India Floristic Interchange.” Climatic phenomena, including monsoons and glaciations, further influenced biodiversity by shaping habitats and driving speciation. High-altitude regions, like the Hengduan Mountains, became biodiversity cradles due to habitat heterogeneity and ecological niches. Advances in tools like palaeoaltimetry proxies, molecular phylogenetics, climate and landscape modelling clarify the complex interactions between tectonics, climate, and biodiversity. Asia's geological history offers vital insights into past climate-biodiversity dynamics, aiding predictions of current ecosystem responses to climate change. This region's unparalleled geological activity and biodiversity make it a focal point for Earth System Science, highlighting the need for interdisciplinary research to address global biodiversity and environmental challenges
La part du genre : genre et approches intersectionnelles dans les sciences sociales françaises au XXIe siècle
No full textInternational audienceQuand s'intéresse-t-on au genre dans les publications de sciences sociales françaises, et qui le fait ? Le fait-on davantage que par le passé, et la production de connaissance sur le genre a-t-elle remplacé l'exploration d'autres rapports de domination comme on l'entend parfois ? Parce qu'il est impossible de consulter l'ensemble de la production universitaire sur une longue période, les spéculations l'emportent souvent sur les analyses empiriques. Afin d'apporter une contribution à ces réflexions, ainsi qu'à l'histoire et à la sociologie des sciences sociales, cet article s'appuie sur des outils issus du traitement automatique des langues -des modèles de langage -pour repérer différentes façons d'explorer les rapports sociaux de sexe dans un vaste corpus. Appliqué aux articles scientifiques de 120 revues de sciences sociales françaises publiées depuis le début du siècle, il offre plusieurs résultats parlants. La part du genre dans les publications académiques a indéniablement progressé au cours des vingt-cinq dernières années, même si le point de départ était souvent bas, et qu'elle reste finalement limitée. Des différences marquées existent entre disciplines, tout comme diffèrent les formes d'institutionnalisation de cette approche. Les connaissances sur le genre sont, en outre, encore très majoritairement produites par des femmes. Enfin, la part des publications articulant le genre à l'exploration d'autres rapports sociaux augmente légèrement, tout en restant très minoritaire, et sans que le genre ne se substitue à la classe
MODELLING SHORELINE DYNAMICS IN COMPLEX MACROTIDAL ENVIRONMENTS USING NEURAL NETWORKS
No full textInternational audienceThe aim of this work is to test an artificial intelligence approach with basic hydrodynamic and morphological variables, in order to assess the effectiveness of such methods in modelling complex beach dynamics. A simple feedforward neural network is used to evaluate the impact of selected variables on the prediction of the dynamics of specific shoreline isocontour proxies extracted from beach profiles, and to build a predictive model that could simulate the position of the proxies. The model was trained on datasets from two sites from the French coastal monitoring program DYNALIT, Porsmilin and Vougot beaches, and their profile measurements, water levels and wave measurements over 20 years. These two sites were selected due to differences in their morphology and hydrodynamics, as a means to assess the performance of neural networks over a larger variety of situations. A range of temporalities encompassing 3 days, 7 days, 14 days, and 30 days of selected hydrodynamic and morphological variables were used to study the impact time scales can have on modelled shoreline positions. The shoreline proxies used for Porsmilin and Vougot beaches correspond respectively to the berm and the contact between the dune toe and the upper beach, which can be assessed and followed along each beach profile. The shallow feedforward network included 1 hidden layer and 5 nodes, and was ran 50 times in order to assess the models' performance. The models were generally successful, with a blind shoreline prediction R of 0.88 in Porsmilin and 0.72 in Vougot. This artificial neural network (ANN) approach showed all-around better performance than previous beach equilibrium models, which is very encouraging regarding the prediction of future beach morphodynamics and the use of Machine Learning algorithms therein.</div
La Toxicologie des pesticides : une recherche engagée par essence
No full textInternational audiencePesticides : entre savoirs inconfortables, règlementation et démocratie sanitaire, l'impossible équation
sRNA-mediated crosstalk between cell wall stress and galactose metabolism in Staphylococcus aureus
No full textInternational audienceStaphylococcus aureus is an opportunistic pathogen responsible for a wide range of diseases in humans. During infections, this bacterium is exposed to various stresses that target its cell wall, such as oxidative or acid environments as well as various cell wall-acting antimicrobials. Staphylococcus aureus has effective regulatory systems for responding to environmental stresses, enabling the expression of factors necessary for its survival. Bacterial small RNAs (sRNAs) play a crucial role in this adaptation process. In this study, we show that RsaOI, an S. aureus sRNA, accumulates under acid stress conditions. This response is mediated via the two-component system VraSR, which is associated with the cell wall damage response. As a component of the VraSR regulon, RsaOI contributes to the survival of S. aureus under acid stress and affects its susceptibility to glycopeptide antibiotics. Our findings reveal that RsaOI targets the lacABCDFEG operon, which encodes components of tagatose pathway, a unique mechanism responsible for galactose metabolism in S. aureus. By antisense base pairing near the ribosome binding site of lacD, RsaOI inhibits the expression of this gene, encoding tagatose-6-phosphate aldolase. This regulation disrupts the tagatose pathway, impairing galactose utilization in S. aureus. These findings highlight the role of RsaOI in the mediation between cell wall stress responses and a specific metabolic pathway
The Impact of Fat Graft Reconstructive Surgery on Prognosis in Young Women with Breast Cancer: A Study from the French Insurance Databases
No full textInternational audienceBackground: Fat grafting (FG) is widely used in breast reconstructive surgery (RS) after mastectomy or lumpectomy for breast cancer (BC); however, concerns persist about its oncologic safety. This study evaluated the impact of FG reconstruction compared with other techniques on BC survival in young women. Methods: The authors identified patients aged 18 to 45 years treated for nonmetastatic BC in the French National Healthcare System Database between January 1, 2010, and December 31, 2018. Patients undergoing FG were matched with patients undergoing other RS on the basis of BC subtype, chemotherapy, radiotherapy, and RS timing after BC surgery. Analyses were stratified on breast surgery (mastectomy or lumpectomy). Results: A total of 50,178 patients were included: 28,260 with luminal tumors, 7982 with triple-negative BC, 7087 with HER2-positive tumors, and 6849 with undefined tumors. In the mastectomy and lumpectomy group, 7333 and 883 patients, respectively, received FG. In the mastectomy group, after matching, FG was associated with better disease-free survival (DFS) (hazard ratio, 0.76 [95% CI, 0.65 to 0.88]) and overall survival compared with patients with other RS. FG also showed improved DFS (hazard ratio, 0.59 [95% CI, 0.51 to 0.69]) compared with patients without any RS. No significant differences in DFS or overall survival were found in the lumpectomy group. Conclusions: FG appears to improve survival outcomes in young women undergoing mastectomy with or without additional RS. In contrast, no significant impact was observed in the lumpectomy group. These findings suggest that FG can be a safe reconstructive option, particularly after mastectomy. Further research is needed to confirm these results and understand the underlying mechanisms. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III
Facial Expressions in Conversational AI: the Hot Trend that Boosts Empathy but Flops on Trust
No full textInternational audienceDynamic facial expressions in AI conversational agents are a rising trend, enhancing emotional engagement and user satisfaction by making interactions feel more personal and engaging. An experimental design comparing two chatbots—one with dynamic expressions and one without—showed that while expressions enhance emotional connection, they fall short in improving trust or advice quality. Absence of expressions fits contexts requiring objectivity and transparency. These findings stress the growing importance of a context-sensitive design in conversational AI, where emotional cues are carefully balanced to match user expectations
Attenuation and polarization of longitudinal critically refracted acoustic wave for residual stress assessment
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Spectacle vivant et territoires
No full textInternational audienceAu travers des métaphores de l'ancrage, de l'encastrement et de l'empreinte, cette communication avait pour objectif de proposer une analyse des réalités complexes qui lient spectacle vivant et territoires, afin d'éclairer les enjeux auxquels est confronté le secteur et d'identifier des leviers et des perspectives faisant sens du point de vue artistique, culturel, social et écologique