HAL Université des Antilles
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Création des filières de FLE: et pendant ce temps là... Il se passait quoi?: Les langues en contact dans l’enseignement du FLE : entre héritage historique et perspectives didactiques
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Prognostic Value of MRI Anatomical Radiologic Scores for one-Year Neurological Outcome after Severe Traumatic Brain Injury
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HIV persistence in tissues on dolutegravir-based therapy is not associated with resistance mutations to dolutegravir
No full textInternational audienceBackgroundRelatively few studies have investigated HIV-1 persistence in tissues, especially in healthy people-living-with-HIV-1 (PLWH) on a successful antiretroviral regimen containing second generation integrase inhibitors.MethodsIn the ANRS EP64 DOLUVOIR, we explore HIV-1 persistence in five accessible anatomical sites in 20 PLWH on an efficient first-line ART regimen containing dolutegravir with virological load <50 copies/mL: PBMCs, rectum, adipose tissue, lymph node and sperm. We quantify total HIV-DNA and cell-associated HIV-1 RNA in different compartments. We sequence HIV-1 DNA for searching drug resistance mutations (DRM) (in RT and INT) and for studying HIV diversity within tissues (ENV). Intact proviral DNA is estimated in PBMCs with an adapted IPDA assay.ResultsBroad ranges of total HIV-DNA and transcripts levels are detected in lymph nodes, PBMCs, adipose tissue and rectum with the highest levels being found in lymph nodes (2.77 log copies HIV-1-DNA/106 cells and 1.50 log copies of HIV-1 cell-associated-RNA/µg RNA). HIV-1 DNA is undetected in all sperm samples (n = 19) except for one (1.52 log copies HIV-1-DNA/106 cells). No difference is noted between the diversity in the four compartments. DRMs to the current regimen are found archived in compartments of six participants. Only two major DRMs to dolutegravir (G118R and R263K) are found archived in two participants. They are the results of APOBEC hypermutations.ConclusionsDespite ongoing transcriptional activity, persistence of HIV-1 in deep tissues is not associated with the selection of DRMs to dolutegravir on intact proviruses. Our results suggest that the detectable transcriptional activity stems predominantly from defective proviral DNA
Diversification and biogeographic history of African dormice (genus Graphiurus) revealed by ultraconserved elements and mitochondrial data
No full textInternational audienceThe sub-Saharan Africa endemic dormouse genus Graphiurus is a morphologically diverse group of rodents that has lacked a genus-wide genetic framework, hindering inference of their evolution and biogeography. Here, we assembled the first comprehensive, range-wide genomic dataset for Graphiurus, including ultraconserved elements and the cytochrome b gene. We used phylogenetic reconstruction, divergence-time estimation, and ancestral area reconstruction to clarify biogeographic histories and evaluate how historical range dynamics may have influenced lineage diversification. Graphiurus is the earliest-diverging lineage within Gliridae sister to all other extant genera. Within Graphiurus, we recovered 24 molecular operational taxonomic units (MOTUs) forming two reciprocally monophyletic, deeply divergent clades: a West African lineage comprising three MOTUs and a pan-sub-Saharan Africa lineage comprising 21 MOTUs. Genetic distances between these clades are equal to or greater than those used to distinguish genera. Diversification within Graphiurus started in the middle Miocene, peaking in a rapid radiation during the Plio-Pleistocene. These diversification events coincided with increased climatic instability that fragmented forests into isolated refugia. Ancestral-area reconstructions suggest a Graphiurus origin in the Upper Guinean rainforest, followed by jump dispersal across the Afrotropics, with most subsequent divergences occurring in East Africa. As the first comprehensive phylogenetic analysis of Graphiurus, our study underscores the urgent need for an integrated taxonomic revision of the genus that couples genomic data with detailed morphology and critical re-examination of type material to resolve species limits and formally describe the recovered MOTUs. Many MOTUs appear range restricted, underscoring vulnerability to ongoing habitat loss within montane refugia
Perinatal challenges for mothers of Haitian origin and their newborns in French Guiana: a historical cohort from 2013 to 2021
No full textInternational audienceObjectives: To describe the sociodemographic characteristics of mothers of Haitian origin and the obstetric and neonatal outcomes of their newborns born in French Guiana between 2013 and 2021 in order to identify specific vulnerabilities within this population.Design: A descriptive, population-based study using data from a comprehensive birth cohort including all deliveries in French Guiana from 2013 to 2021.Setting: All maternity units in French Guiana, a French overseas territory located in South America.Participants: A total of 66 485 live births were recorded during the study period, including 14 065 (21.2%) births to mothers of Haitian origin.Primary and secondary outcome measures: Sociodemographic characteristics, antenatal care indicators and neonatal outcomes were compared between mothers of Haitian origin and mothers of other origins. Adjusted odds ratios (aOR) and 95% CI were calculated for key outcomes.Results: Compared with mothers of other origins, Haitian mothers had higher odds of delivering a newborn small for gestational age (aOR=1.41, 95% CI 1.32 to 1.50), neonatal hospitalisation at birth (aOR=1.19, 95% CI 1.11 to 1.28), having an insufficient number of antenatal visits (aOR=1.32, 95% CI 1.26 to 1.38) and lacking health insurance coverage (aOR=2.83, 95% CI 2.52 to 3.17). Conversely, they had a lower risk of adolescent pregnancy (<20 years; aOR=0.24, 95% CI 0.21 to 0.26). The risk of preterm birth did not differ significantly between groups (p=0.24).Conclusion: Mothers of Haitian origin in French Guiana experience distinct social and perinatal vulnerabilities. Strengthening equitable access to healthcare and implementing targeted community-based interventions are essential to improve maternal and neonatal health outcomes in this population
Toward an understanding of microalgae EPS-based selectivity and binding mechanisms for trace metal ions using Love wave acoustic and voltammetric sensors in seawater
No full textInternational audienceA biosensor using microalgal extracellular polymeric substances (EPS) for real-time monitoring of six trace metals in seawater, combining acoustic and electrochemical signatures for high sensitivity
Mineralogical constraints on carbon deportment in phosphate ores: Implications for decarbonizing ore processing
No full textInternational audienceThe release of CO2 from carbon-bearing minerals during phosphate ore processing contributes to industrial emissions but remains poorly quantified. This study examines the Bouchane phosphate deposit, part of the Gantour Basin in Morocco, which consists of Upper Cretaceous–Paleogene sedimentary phosphates. The objective is to constrain the proportions and deportment of carbon within its mineral phases and assess their contribution to CO2 release during beneficiation and acidulation. For this purpose, 20 representative samples from a stratigraphic section of the deposit were analyzed for petrographic composition, bulk mineralogy by X-ray diffraction, bulk geochemistry by inductively coupled plasma optical emission spectroscopy (ICP-OES), and total carbon by induction furnace, complemented by in-situ microanalyses using an electron probe micro-analyzer (EPMA) and quantitative automated mineralogy with a TESCAN Integrated Mineral Analyzer (TIMA). Moreover, the modal composition of the studied samples was determined using various approaches such as quantitative X-ray diffraction (QXRD), quantitative automated mineralogy (QAM), element-to-mineral conversion (EMC), and total inversion (TI). The studied samples were predominantly composed of phosphatic coated grains, peloids, coprolites, and skeletal particles. The chemistry of these sediments varied along the stratigraphic section, marked by a dominance of inorganic carbon compared to organic carbon, with a mean content of 11.38 ± 4.58 wt% and 0.68 ± 0.03 wt%, respectively. The developed calculated mineralogy techniques (EMC, TI) proved successful in accurate quantification of the modal composition of the phosphate sediments. Automated mineralogy by TIMA provided a quantification of the percentage of problematic locked carbonates within phosphatic grains, with values below 3 %. These grains were predicted to hold 11 % of the CO2 in carbonate fluorapatite (CFA), and 0.3 % and 0.1 % in calcite and dolomite, respectively. The remaining carbonate phases are removed during washing and flotation. This study shows that adopting holistic approaches in phosphate mining is efficient for developing rapid, low-cost techniques for mineralogical characterization (EMC, TI) and indicates that phosphate rock processing results in limited in situ CO2 release from carbonate minerals
Étude exploratoire sur les usages, l’adoption de l’intelligence artificielle générative par les professionnels de l’éducation en formation initiale dans des territoires francophones du Québec (Canada), de l’Alsace (France) et des Antilles françaises (Martinique et Guadeloupe).
No full textFace à l’essor rapide de l’intelligence artificielle générative (IAG), cette étude exploratoire s’intéresse à la manière dont les futurs professionnels de l’éducation perçoivent et anticipent les transformations pédagogiques et professionnelles qu’elle engendre. Conduite dans trois contextes francophones contrastés (le Canada, la Haute-Alsace et les Antilles françaises), cette recherche vise à comprendre comment les modalités d’usage, d’adoption et de représentation de l’IA varient selon les ancrages culturels et institutionnels. Ancrée dans la théorie de l’activité (Engeström, 1999, 2014), notre démarche s’appuie sur un design qualitatif de type exploratoire, intégrant un questionnaire à visée compréhensive. L’analyse des données a été réalisée en deux temps : d’abord à l’aide d’outils d’IA générative (ChatGPT et Claude.ai), puis par triangulation humaine. Cette double lecture thématique a permis d’identifier cinq représentations majeures de l’IA chez les professionnels de l’éducation en formation initiale : outil technologique, assistant, système algorithmique, intelligence non humaine, et automate de tâches. Les résultats révèlent des variations significatives selon les contextes : les participants antillais valorisent fortement l’IA comme outil ou assistant, tandis que d’autres perçoivent une redéfinition des rôles enseignants vers des fonctions plus stratégiques. La division du travail avec l’IAG est ainsi anticipée comme évolutive, mais non conflictuelle, mettant en lumière le besoin d’une formation ciblée et contextualisée sur les responsabilités partagées entre humains et IAG. Ces résultats soulignent l’importance d’ancrer les stratégies de formation dans une compréhension fine des représentations et des dynamiques territoriales
Une nouvelle distance multi-experte pour le partitionnement automatique des paramètres climatiques : une étude de cas sur les précipitations dans les Caraïbes
No full textInternational audienceThis study investigates precipitation patterns in the Caribbean region using a novel Multi-Expert Distance (MED) metric for clustering analysis. MED integrates multiple climate parameters, including Sea Surface Temperature (SST), wind components at 925 hPa, and Outgoing Longwave Radiation (OLR), with the objective of enhancing spatiotemporal precipitation analysis. This approach offers an alternative to conventional methods that rely on single datasets and Euclidean distances. It combines physical parameters during clustering to enhance accuracy and insights. The analysis encompasses a 43-year period (1979-2021), extending from the Gulf of Mexico to the Caribbean, with a spatial extent that covers the entire region. The MED metric incorporates zone-specific his-tograms and Kullback-Leibler divergence, enabling dynamic comparisons of atmospheric configurations. The analysis yielded six distinct clusters, each exhibiting unique seasonal and inter-annual precipitation patterns, influenced by regional atmospheric dynamics. The analysis revealed significant transitions and associations between clusters, precipitation levels, and atmospheric conditions. Clusters representing dry conditions exhibited negative SST anomalies, reflecting reduced moisture production. Conversely, clusters exhibiting high precipitation exhibited positive SST anomalies, which are conducive to moisture accumulation. Furthermore, tropical storms and hurricanes were predominantly observed in wetter clusters, underscoring the utility of MED in linking atmospheric phenomena with climatic impacts. The results highlight the effectiveness of the MED in improving both the accuracy and interpretability of clustering algorithms. Beyond its methodological contributions, this work highlights the MED's potential to advance the understanding and forecasting of precipitation regimes, thereby contributing to more robust climate analyses. Such insights are particularly relevant for informing climate adaptation strategies in vulnerable regions, notably the Caribbean. Future research could investigate automated domain segmentation as a means of further refining and optimizing this approach.Cette étude examine les régimes de précipitations dans la région des Caraïbes en utilisant une nouvelle métrique appelée Distance Multi-Expert (MED) pour l’analyse par regroupement. La MED intègre plusieurs paramètres climatiques, notamment la température de surface de la mer (SST), les composantes du vent à 925 hPa et le rayonnement infrarouge sortant (OLR), dans le but d’améliorer l’analyse spatio-temporelle des précipitations. Cette approche constitue une alternative aux méthodes conventionnelles reposant sur des ensembles de données uniques et des distances euclidiennes. Elle combine des paramètres physiques lors du regroupement afin d’accroître la précision et la pertinence des résultats.L’analyse couvre une période de 43 ans (1979–2021), s’étendant du golfe du Mexique aux Caraïbes, avec une couverture spatiale englobant toute la région. La métrique MED intègre des histogrammes spécifiques à chaque zone ainsi que la divergence de Kullback-Leibler, permettant des comparaisons dynamiques des configurations atmosphériques. L’étude a permis d’identifier six groupes distincts, chacun présentant des régimes de précipitations saisonniers et interannuels uniques, influencés par les dynamiques atmosphériques régionales. Elle a révélé des transitions significatives et des associations entre les groupes, les niveaux de précipitations et les conditions atmosphériques. Les groupes représentant des conditions sèches présentaient des anomalies négatives de SST, traduisant une production d’humidité réduite. À l’inverse, les groupes caractérisés par de fortes précipitations affichaient des anomalies positives de SST, favorables à l’accumulation d’humidité. De plus, les tempêtes tropicales et les ouragans ont été principalement observés dans les groupes les plus humides, soulignant l’utilité de la MED pour relier les phénomènes atmosphériques aux impacts climatiques. Les résultats mettent en évidence l’efficacité de la MED pour améliorer à la fois la précision et l’interprétabilité des algorithmes de regroupement. Au-delà de ses contributions méthodologiques, ce travail souligne le potentiel de la MED pour faire progresser la compréhension et la prévision des régimes de précipitations, contribuant ainsi à des analyses climatiques plus robustes. Ces connaissances sont particulièrement pertinentes pour orienter les stratégies d’adaptation climatique dans les régions vulnérables, notamment les Caraïbes. Des recherches futures pourraient explorer la segmentation automatisée des domaines comme moyen d’affiner et d’optimiser davantage cette approche
Identity and the Self. How Archaeology Creates Protohistoric Identities
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