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Taxonomical and functional changes in COVID-19 faecal microbiome are related to SARS-CoV-2 faecal load
No full textAbstract Since the beginning of the pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) the gastro-intestinal (GI) tract has emerged as an important organ influencing the propensity to and potentially severity of the related COVID-19 disease. However, the contribution of the SARS-CoV-2 intestinal infection on COVID-19 pathogenesis remains to be clarified. In this exploratory study, we evidenced that alterations in the composition of the gut microbiota depends on the levels of SARS-CoV-2 RNA in the gastrointestinal tract but not on the presence of SARS-CoV-2 in the respiratory tract, COVID-19 severity and GI symptoms. Altered molecular functions in the microbiota profiles of high SARS-CoV-2 RNA level faeces as established by metaproteomics highlight mechanisms that may contribute to vicious cycles. Uncovering the role of this gut microbiota dysbiosis could drive the investigation of alternative therapeutic strategies to favour the clearance of the virus and potentially mitigate the effect of SARS-CoV-2 infection
"Responsabilité du praticien en cas de non respect du cadre juridique de l'IVG, Commentaire sur CA Paris, 7 nov. 2024", Revue Droit de la famille, 1, 2025
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"Responsabilité du praticien en cas de non respect du cadre juridique de l'IVG, Commentaire sur CA Paris, 7 nov. 2024"
No full textInternational audienc
MLKAPS: Machine Learning and Adaptive Sampling for HPC Kernel Auto-tuning
No full textInternational audienceMany High-Performance Computing (HPC) libraries rely on decision trees to select the best kernel hyperparameters at runtime,depending on the input and environment. However, finding optimized configurations for each input and environment is challengingand requires significant manual effort and computational resources. This paper presents MLKAPS, a tool that automates this task usingmachine learning and adaptive sampling techniques. MLKAPS generates decision trees that tune HPC kernels’ design parameters toachieve efficient performance for any user input. MLKAPS scales to large input and design spaces, outperforming similar state-of-the-artauto-tuning tools in tuning time and mean speedup. We demonstrate the benefits of MLKAPS on the highly optimized Intel MKLdgetrf LU kernel and show that MLKAPS finds blindspots in the manual tuning of HPC experts. It improves over 85% of the inputswith a geomean speedup of ×1.30. On the Intel MKL dgeqrf QR kernel, MLKAPS improves performance on 85% of the inputs with ageomean speedup of ×1.18
SARS-CoV-2 epidemiology, kinetics, and evolution: A narrative review
No full textInternational audienceSince winter 2019, SARS-CoV-2 has emerged, spread, and evolved all around the globe. We explore 4 y of evolutionary epidemiology of this virus, ranging from the applied public health challenges to the more conceptual evolutionary biology perspectives. Through this review, we first present the spread and lethality of the infections it causes, starting from its emergence in Wuhan (China) from the initial epidemics all around the world, compare the virus to other betacoronaviruses, focus on its airborne transmission, compare containment strategies ("zero-COVID" vs. "herd immunity"), explain its phylogeographical tracking, underline the importance of natural selection on the epidemics, mention its within-host population dynamics. Finally, we discuss how the pandemic has transformed (or should transform) the surveillance and prevention of viral respiratory infections and identify perspectives for the research on epidemiology of COVID-19
Malnutrition and Climate in Niger: Findings from Climate Indices and Crop Yield Simulations
No full textInternational audienceMalnutrition, particularly its impact on child morbidity and mortality, is one of the top five health effects of climate change. However, quantifying the portion of malnutrition attributed to climate remains challenging due to various confounding factors. This study examines the relationship between climate and acute malnutrition in Niger, a country highly vulnerable to climate change and disasters. Since climate’s effect on malnutrition is indirect, mediated by crop production, we combine rainfall data from TAMSAT satellite estimates with the SARRA-O crop model, which simulates the impact of rainfall variability on crop yields. Our analysis reveals a significant correlation between malnutrition and both rainfall and crop production from the previous year, but not within the same year. The strongest correlation (R = −0.72) was found with the previous year’s crop production. No significant links were found with temperature or intra-seasonal rainfall indices, like the start or duration of the rainy season. Although national correlations between global malnutrition, rainfall, and crop yields were stronger, they were weaker or absent at the regional level and, for Severe Acute Malnutrition crises, are less likely driven by climate variability. However, the one-year lag in the correlation allows for the prediction of future food crises, providing an opportunity to implement early intervention measures
Pratiques agricoles et défis climatiques en Océanie : regards croisés entre sciences sociales et climatologie
No full textInternational audienceIn a context of marked climate change, agricultural practices and knowledge in the Pacific are undergoing profound transformations. Increasing climate variability, particularly concerning water resources, presents major challenges for local agri-food systems, raising questions of adaptation, resilience, and knowledge transmission. What strategies are local communities developing to adapt to these environmental changes? What are the current limitations and future challenges for agriculture in the face of these new water-related constraints?To explore these issues, IRD and Météo-France organized a scientific mediation event open to the general public. This event offered a cross-perspective between social sciences and climatology through several key moments:A visual presentation of how New Caledonian children perceive climate change, illustrating intergenerational perspectives on these transformations;A showcase of public speaking performances by young individuals engaged in defending their territories, highlighting the dynamics of social mobilization in response to environmental challenges;A discussion with a panel of researchers in social sciences and climate sciences, sharing their latest findings;A screening of the documentary Paradise in Peril, which examines the understanding of climatic phenomena in New Caledonia and the adaptation of lifestyles in response to these disruptions.Dans un contexte de changements climatiques marqués, les pratiques et savoirs agricoles du Pacifique font face à des mutations profondes. La variabilité climatique accrue, notamment en lien avec la ressource en eau, impose des défis majeurs aux systèmes agroalimentaires locaux, soulevant des questions d’adaptation, de résilience et de transmission des savoirs. Quelles sont les stratégies développées par les communautés locales pour s’adapter à ces transformations environnementales ? Quels sont les limites et les défis futurs pour l’agriculture face à ces nouvelles contraintes hydriques ?Afin d’explorer ces enjeux, l’IRD et Météo-France organisent une soirée de médiation scientifique ouverte au grand public. Cet événement a proposé un regard croisé entre sciences sociales et climatologie à travers plusieurs temps forts :Une restitution visuelle du ressenti des enfants calédoniens face au changement climatique, illustrant la perception intergénérationnelle de ces transformations ;Une mise en lumière des performances oratoires de jeunes engagés pour leur territoire, témoignant des dynamiques de mobilisation sociale face aux enjeux environnementaux ;Une discussion avec un panel de chercheurs en sciences sociales et en sciences du climat, partageant leurs résultats récents ;La projection du documentaire Paradis en péril, qui analyse la compréhension des phénomènes climatiques en Nouvelle-Calédonie et l’évolution des modes de vie face à ces bouleversements
Impact des chatbots sur l'expérience utilisateur et la qualité des données sur les plateformes de sciences citoyennes
No full textInternational audienceCitizen science (CS) projects, which engage the general public in scientific research, often face challenges in ensuring high-quality data collection and maintaining user engagement. Recent advancements in Large Language Models (LLMs) present a promising solution by providing automated, real-time assistance to users, reducing the need for extensive human intervention, and offering instant support. The CS project Les Herbonautes, dedicated to mass digitization of the French National Herbarium, serves as a case study for this paper, which details the development and evaluation of a network of open source LLM agents to assist users during data collection. The research involved the review of related work, stakeholder meetings with the Muséum National d’Histoire Naturelle, and user and context analyses to formalize system requirements. With these, a prototype with a user interface in the form of a chatbot was designed and implemented using LangGraph, and afterward evaluated through expert evaluation to assess its effect on usability and user experience (UX). The findings indicate that such a chatbot can enhance UX and improve data quality by guiding users and providing immediate feedback. However, limitations due to the non-deterministic nature of LLMs exist, suggesting that workflows must be carefully designed to mitigate potential errors and ensure reliable performance
No-regret and low-regret controls of space-time fractionalparabolic Sturm-Liouville equations in a star graph
No full textInternational audienceWe are concerned with a space-time fractional parabolic initial-boundary value problemof Sturm-Liouville type in a general star graph with mixedDirichlet and Neumannboundary controls. We first give several existence, uniqueness and regularity resultsof weak and very-weak solutions. Using the notion of no-regret control introducedby Lions, we prove the existence, uniqueness, and characterize the low regret controlof a quadratic boundary optimal control problem, then we prove that this low regretcontrol converges to the no-regret control and we provide the associated optimalitysystems and conditions that characterize that no-regret control
Assessing the invasion risk of the cnidaria Blackfordia virginica Mayer, 1910: a threat to the Baltic Sea ecosystem?
No full textInternational audienceThe ecological role, bloom extent and long-term dynamics of jellyfishes are mostly overlooked due to sampling limitations, leading to the lack of continuous long-term datasets. A rise in frequency and magnitude of jellyfish invasion around the world is shedding new light on these organisms. In this study, we estimate the current and future distribution of the introduced jellyfish Blackfordia virginica in the Baltic Sea. We determine the combination of favorable levels of temperature and salinity for this species by analyzing presence/absence data from areas outside the Baltic Sea and project the distribution of suitable habitat in the Baltic Sea across different scenarios with variable climate forcing and eutrophication levels. Our results show that suitability increases with rising temperature and optimal salinity range from 13 to 20 for this species. In addition, a relatively large area of the Baltic Sea represents favorable abiotic conditions for B. virginica , enhancing the concerns on its potential range expansion. Spatial analysis illustrates that the coastal areas of the southern Baltic Sea are particularly at risk for the invasion of the species. The observation of the projection of habitat suitability across time highlights that future Baltic Sea environmental conditions increase suitability levels for B. virginica and suggest a potential expansion of its distribution in the future