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Polygenic risk scores for severe psychiatric disorders in bipolar disorders: associations with the clinical and dimensional expression, interactions with childhood maltreatment and mediation models
No full textInternational audiencePolygenic risk scores (PRSs) for several psychiatric disorders have been associated with the clinical presentation of bipolar disorder (BD). PRSs have also been suggested to moderate the associations between childhood maltreatment and BD severity. In this study, we investigated how PRSs for BD, schizophrenia, major depressive disorders (MDD) and attention-deficit/hyperactivity disorder (ADHD) might disentangle the clinical and dimensional heterogeneity of BD in a sample of 852 affected individuals. We used logistic and linear regressions, moderation and mediation models to test the associations between PRSs, dimensions in childhood/adulthood and clinical indicators of severity of BD. All models were adjusted for age, sex, BD type and depressive symptoms. None of the PRSs were significantly associated with the clinical expression of BD when considered in terms of mode of onset, course, or psychiatric comorbidities. Nevertheless, the PRS-ADHD significantly and positively correlated with the levels of childhood maltreatment, childhood ADHD symptoms, and of some adulthood measures (affective lability, impulsivity and hostility) with p values ranging from 3.10-8-4.10-4. None of the PRSs moderated the effects of childhood maltreatment on the clinical or dimensional variables. Mediation model suggested paths from both PRS-ADHD and PRS-MDD to childhood ADHD symptoms and childhood maltreatment. The links between PRS-ADHD to all adulthood dimensions were mediated by childhood ADHD symptoms (p < 0.002). In turn, some adulthood dimensions (mainly affect intensity and affective lability) were associated with the clinical severity of BD, as defined by rapid cycling, suicide attempts and anxiety disorders. In conclusion, this study disentangles the associations between the genetic liability for four psychiatric disorders and the clinical/dimensional heterogeneity of BD. We suggest a continuum from the genetic risk for ADHD and MDD through dimensions in childhood/adulthood to a severe/complex clinical expression of BD
Exploring Bird Gut Microbiota Through Opportunistic Fecal Sampling: Ecological and Evolutionary Perspectives
No full textInternational audienceWetland ecosystems are facing alarming rates of destruction and degradation, posing significant challenges for avian populations reliant on these habitats. Bird health is closely linked to the composition of their intestinal microbiota, which is primarily influenced by local conditions, primarily through diet. Building on our previous work identifying dietary variations among bird populations in marshes within a Ramsar site along the Somme and Avre rivers (France), this pilot study aimed to assess the relevance of using fecal samples collected from the ground to characterize avian intestinal microbiota via 16S rRNA metabarcoding. We hypothesized that this noninvasive sampling method would capture how bird traits and environmental factors shape fecal microbiota composition. Sampling was conducted during the breeding season at seven locations (six within the Ramsar site and one on its outskirts) spanning rural or peri‐urban environments. A total of 52 fecal samples from nine bird species or families, predominantly waterbirds, were analyzed for bacterial composition. At the phylum level, Firmicutes and Proteobacteria were predominant, with the relative abundance of genera such as Clostridium , Rothia , Bacillus , Caldilinea and Pseudomonas varying among bird species. The potential enteropathogen Campylobacter was primarily detected in samples from peri‐urban sites. Multivariate analyses revealed significant variations in bacterial composition associated with bird trophic guild, ecology, body length, pond surface and habitat location. Additionally, a weak correlation was observed between host phylogeny and microbiota composition. Although the limited sample size, particularly for some species, constrains the robustness of these findings, the observed trends align with ecological expectations. This study highlights the potential of opportunistically collected fecal samples as a low‐impact tool for exploring the relationship between bird gut microbiota and their habitat
Evolutions des vulnérabilités face aux risques hydroclimatiques aux Antilles françaises : les cas de Saint-Martin et de la Guadeloupe, 2015-2025
No full textInternational audienceThe French Antilles are territories with a high level of hydroclimatic risk (IPCC, 2023). This risk is the result of a combination of high exposure to hazards, which is increasing due to climate change, and multiple vulnerabilities rooted in socio-territorial systems. Despite this observation, most current prevention strategies do not explicitly take into account the specific socio-economic vulnerabilities of these territories and how they are changing (Moatty et al., 2021). This can be partly explained by the lack of quantitative tools adapted to the specific territorial characteristics of the French Caribbean overseas territories and capable of showing changes in vulnerabilities at different scales (Leone, 2007). In order to help fill this gap and characterize the risk more precisely, this research proposes to adapt a vulnerability index developed for the US Virgin Islands (Guannel et al., 2022) to the territories of Saint Martin and Guadeloupe. This index makes it possible to identify changes in vulnerabilities in territories at different scales, from islands to neighborhoods. The decision was made to focus on priority urban districts as they concentrate significant socio-economic vulnerabilities. Our study focuses more specifically on the period 2015-2025 in order to analyze the potential consequences of Hurricane Irma's passage through the Caribbean basin in 2017. The study of the evolution of vulnerabilities over this period shows an overall decrease in vulnerabilities in Guadeloupe and Saint Martin. However, a more detailed analysis shows that this trend is not linear across all types of vulnerabilities (demographic, economic, material, and socio-linguistic), nor is it homogeneous across all territories. Intergovernmental Panel on Climate Change (2023) Sixth Assessment Report. Guannel, G., Lohman, H. et Dwyer, J. (2022) ‘Social and Flooding Vulnerability in the U.S. Virgin Islands’, Natural Hazards Center Public Health Report Series.Leone, F. (2007) Caractérisation des vulnérabilités aux catastrophes ” naturelles ” : contribution à une évaluation géographique multirisque (mouvements de terrain, séismes, tsunamis, éruptions volcaniques, cyclones). Université Paul Valéry, Montpellier III.Moatty, A., Grancher, D. et Duvat, V. (2021) ‘Leverages and obstacles facing post-cyclone recovery in Saint-Martin, Caribbean: Between the “window of opportunity” and the “systemic risk”?’, International Journal of Disaster Risk Reduction, 63.Les Antilles françaises sont des territoires qui enregistrent un haut niveau de risque hydroclimatique (GIEC, 2023). Ce risque est le résultat d’une coprésence entre une forte exposition aux aléas, grandissante en raison des changements climatiques, et des vulnérabilités multiples enracinées dans les systèmes socio-territoriaux. Malgré ce constat, la plupart des stratégies de prévention actuelles ne prennent pas explicitement en compte les vulnérabilités socio-économiques spécifiques à ces territoires et leurs évolutions (Moatty et al., 2021). Cette lacune peut en partie s’expliquer par le manque d’outils quantitatifs adaptés aux spécificités territoriales des outre-mer caribéens français, et capables de donner à voir les évolutions à différentes échelles (Leone, 2007). Afin de contribuer à combler cette lacune et caractériser plus finement le risque, ce travail de recherche propose d’adapter un indice de vulnérabilité développé pour les Iles vierges américaines (Guannel et al., 2022) aux territoires de Saint-Martin et de la Guadeloupe. Cet indice permet de cerner les évolutions des vulnérabilités sur des territoires à différentes échelles, depuis celle de l’île, jusqu’à celle des quartiers. Le choix a été fait de se focaliser sur des quartiers prioritaires au titre de la politique de la ville (QPV) en ce qu’ils concentrent des vulnérabilités socio-économiques fortes. Notre étude porte plus spécifiquement sur la période 2015-2025 afin d’analyser les conséquences potentielles du passage du cyclone Irma dans le bassin caraïbe en 2017. L’étude de l’évolution des vulnérabilités sur cette période fait ressortir une diminution globale de ces dernières en Guadeloupe et à Saint-Martin. Cependant, l’analyse à une échelle plus fine montre que cette tendance n’est pas linéaire selon les types de vulnérabilités (démographiques, économiques, matérielles et socio-linguistiques), ni homogène sur l’ensemble des territoires. Groupement Intergouvernemental des Experts sur le Climat (2023) Sixième rapport d’évaluation.Guannel, G., Lohman, H. et Dwyer, J. (2022) ‘Social and Flooding Vulnerability in the U.S. Virgin Islands’, Natural Hazards Center Public Health Report Series.Leone, F. (2007) Caractérisation des vulnérabilités aux catastrophes ” naturelles ” : contribution à une évaluation géographique multirisque (mouvements de terrain, séismes, tsunamis, éruptions volcaniques, cyclones). Université Paul Valéry, Montpellier III.Moatty, A., Grancher, D. et Duvat, V. (2021) ‘Leverages and obstacles facing post-cyclone recovery in Saint-Martin, Caribbean: Between the “window of opportunity” and the “systemic risk”?’, International Journal of Disaster Risk Reduction, 63
Caution is Warranted When Applying Algorithms for Assessing Left Ventricular Diastolic Dysfunction and Filling Pressure in Critically Ill Patients
No full textInternational audienceNo abstract
High-pressure, high-temperature CALPHAD modelling of Ir–Os–Pt system
No full textInternational audienceIn this paper, we use the CALPHAD method to describe iridium at high pressure and high temperature, based on the Lu's model as revisited by Joubert et al. (Calphad: Comput. Coupling Phase Diagrams Thermochem., 74 (2021) 102304). A comprehensive literature review allowed us to obtain the equation of state for both the solid and liquid phases of Ir. We optimized the ambient-pressure phase diagrams of the Ir-Os and Ir-Pt systems with the experimental data from the literature and calculations performed in this study The successful reproduction of high-pressure experimental data for these alloys for the binary Ir-Os system, suggests a reliable description of both pure elements. Consequently, we can propose, for the first time, an extrapolation of the Ir-Os-Pt ternary diagram based on the descriptions of the binary systems
Introduction. Coproduire la ville « par le bas », perspectives franco-brésiliennes
No full textInternational audienceConcept très large, la coproduction est mobilisée tant dans le champ scientifique que dans celui des politiques publiques pour désigner des pratiques collaboratives impliquant une diversité d’acteurs dans la production de services ou de biens communs, souvent liés à des droits fondamentaux (santé, logement, éducation, etc.). Cet article propose de revisiter les usages divers du concept, depuis les théories de l’action collective ancrées dans la réalité des Suds jusqu’aux approches institutionnelles portées à l’échelle nationale ou globale. À partir de ce retour historique et critique sur le concept et ses usages, les auteurs proposent une définition du terme appliqué spécifiquement à la production de la ville. Le terme de co-production urbaine est ainsi proposé afin de rendre compte d’une diversité de pratiques collaboratives dans la ville, ancrées dans des mobilisations locales en faveur de la justice spatiale. Cet article introduit un dossier thématique de la revue Participations intitulé « Co-produire la ville par le bas : perspectives franco-brésiliennes ». Organisé par les trois auteurs de l’article, ce dossier inclut des travaux de chercheurs français et brésiliens témoignant de recherches collaboratives développées dans le cadre du projet ANR CoPolis, Co-production sociale de la ville et recherche citoyenne (2020-2024), associant universitaires, techniciens, professionnels et collectifs d’habitants dans des quartiers populaires de plusieurs villes au Brésil et en France
Wind Erosion Dynamics Associated With Land Use on Sandy Soils Under Heavy Anthropogenic Pressure (Southwestern Niger)
No full textInternational audienceABSTRACT Heavy anthropic pressures and rainfall crises have led to land degradation and increased the intensity of wind erosion in arid areas. This erosion transports soil particles and associated nutrients and contributes to the degradation of cultivated and grazed land. The aim of this study is to assess the intensity of wind flux in relation to land use on the Namaro dune ridge, with sandy soils representative of south‐western Niger in central Sahel. Its surface is essentially dominated by millet fields and rangelands. The methodological approach consisted in monitoring soil cover by vegetation on a rangeland and a millet field, meteorological parameters (rainfall, wind speed, and direction) and associated wind erosion flux over two annual cycles. Precise, concomitant measurements of saltation and wind speed were used to determine wind erosion threshold velocity for both land uses. Wind erosion flux was measured using sand traps (BSNE) and saltation detectors: sensit and saltiphone. The potential wind erosion flux was also determined. The two land uses show the lowest land cover at the end of the dry and the beginning of the rainy season when the winds are strongest. It appeared that the millet field is at all times more covered by vegetation than the rangeland. This difference can be explained by the high grazing pressure on the dune complex, which is maintained throughout the year. As a result, the threshold velocity, which is always lower on the rangeland, was 6.1 m s −1 compared with 7.3 m s −1 on the millet field. From July to December, as vegetation developed, threshold velocities increased, reaching 9.6 and 11.1 m s −1 , respectively, on the grazing land and the field. In agreement with the vegetation cover, dust uplift potential and threshold velocities, horizontal erosion flux and saltation were at least two times greater on the rangeland than on the millet field. This is the first time in the Sahel that measurements have shown that rangelands can be more erodible than cultivated fields for the same weather conditions. For better rangeland soil management, it will be necessary to control grazing pressure with an implication of local people. It is also important to minimize grazing pressure during the rainy season. During this period, high grazing pressure will result in poor vegetation cover and soils that are more susceptible to wind erosion from the start of the dry season
A systematic benchmark of bioinformatics methods for single-cell and spatial RNA-seq Nanopore long-read data
No full textAlternative splicing plays a crucial role in transcriptomic complexity, yet remains difficult to resolve at the singlecell level due to the limitations of short-read technologies. Coupling single-cell with long-read sequencing offers fulllength transcript coverage, enabling more accurate isoform detection. Multiple specialized computational tools tailored for single-cell and spatial long-read transcriptomics have been developed, with diverse strategies. To compare the effectiveness of these approaches, we generated paired shortread and Nanopore long-read single-cell datasets, tailored for benchmarking bioinformatics tools. We evaluated ten state-ofthe-art methods, spanning four analytical dimensions: barcodes and UMI detection, demultiplexing and UMI clustering, gene-level expression profiling, and isoform detection and quantification.Using real and simulated datasets across different protocols, sequencing depths and chemistries, we assessed the accuracy, robustness, and scalability of each tool. Our results revealed method-specific trade-offs, and highlight the importance of sequencing quality and UMI correction strategies. This benchmark provides a practical resource for optimizing isoform analysis and accurate gene expression profiling in single-cell and spatial transcriptomics using longread sequencing. Our benchmarking workflow is designed to be reusable, thereby enabling method developers to compare their own approaches against the set of reference methods evaluated in this work. single-cell | long-read | spatial transcriptomics | isoforms | benchmark</div
Noninvasive respiratory supports in ICU
No full textInternational audienceBackground: Noninvasive respiratory supports are routinely applied in critically ill patients with acute respiratory failure to avoid intubation and invasive mechanical ventilation, thereby reducing the risk of related complications, and to facilitate successful weaning from mechanical ventilation after extubation. They are also applied during the intubation procedure for preoxygenation with the aim of enhancing oxygenation and ensuring the safety of the procedure.Main body: High-flow nasal oxygen decreases airway dead space, provides a stable concentration of inspired oxygen, generates low level of flow-dependent positive airway pressure, and optimizes comfort. Positive-pressure noninvasive supports include continuous positive-airway pressure and noninvasive ventilation and enable providing higher end-expiratory pressure, thereby further improving oxygenation. Noninvasive ventilation, but not continuous positive-airway pressure, better decreases inspiratory effort, and increases tidal volume and transpulmonary driving pressure.Conclusion: High-flow nasal oxygen has become the first-line therapy in acute hypoxemic respiratory failure, while noninvasive ventilation remains the reference treatment during exacerbations of chronic obstructive pulmonary disease, in patients with respiratory acidosis. In patients requiring intubation, noninvasive ventilation is the optimal technique for preoxygenation to decrease the risk of hypoxemia, while high-flow nasal oxygen is an alternative option for non-hypoxemic patients or those with contraindications to noninvasive ventilation. After extubation in patients at high risk of reintubation, prophylactic noninvasive ventilation, eventually alternating with high-flow nasal oxygen, improves weaning outcome compared to other strategies; high-flow nasal oxygen alone outperforms conventional oxygen in low-risk patients
La plaine alluviale de la Bassée : comment re-penser les solidarités au travers de l’eau et de la biodiversité?
No full textInternational audienceLa Bassée is a flood plain of the Seine River located in two départements (Aube and Seine-et-Marne), comprising several conurbations and stretching from the Aube-Seine confluence upstream (Romilly sur Seine) to the Seine-Yonne confluence downstream (near Montereau-Fault-sur-Yonne). This area, where the hydrogeological functioning of the river’s major bed has been heavily impacted by the development projects, is at the crossroads of a number of issues (alluvial deposits exploitation, drinking water supply of the Paris metropolitan area, flood prevention for downstream areas, etc.). La Bassée is therefore an area contributing to the resilience of other areas downstream.This independency raises questions about the capacity of this territory and the related stakeholders to develop their own strategy and to build a a territorial project that could be more autonomous. The aim of our research was therefore to explore the logics of solidarity and negotiation between stakeholders and their vision of the desired biodiversity (through different objects: water, preservation of species, creation of a new nature reserve). The question of solidarity within the Bassée-Voulzie area, and between it and downstream areas (particularly the Paris metropolis), has long been a source of frustration linked to the exploitation of water and sediment resources and the subsequent development of aquatic environments. In this paper, we examine some of the scenes in which a variety of stakeholders meet and compare their visions of the territory. We highlight how projects are negotiated at scales ranging from the upstream Seine basin to river branches or water reservoirs, and to what extent these multiple negotiations offer a perspective for joint and environmental management of the river.La Bassée est une vaste plaine alluviale de la Seine à cheval sur deux départements (Aube et Seine-et-Marne), comptant plusieurs intercommunalités et qui s’étend de la confluence Aube-Seine en amont (Romilly sur Seine) et la confluence Seine-Yonne en aval (à la hauteur de Montereau-Fault-sur-Yonne). Ce territoire dont le fonctionnement hydrogéologique du lit majeur a été très fortement impacté par les aménagements du fleuve est à l’intersection de plusieurs enjeux (prélèvements d’alluvions et d’eau potable pour l’approvisionnement de la métropole parisienne, prévention des inondations des territoires situés à l’aval…). La Bassée est donc un territoire qui participe à la résilience d’autres territoires à l’aval. Se posent ainsi des questions sur la capacité de cet espace à construire une logique d’action propre et à repenser ses (inter)dépendances pour ne pas être seulement le réceptacle de projets venus d’ailleurs. L’objectif de notre recherche était donc d’explorer les logiques de solidarité, de négociations entre les acteurs et les visions et la place accordées à la biodiversité (via différents objets : eau, préservation des espèces, constitution d’une nouvelle réserve naturelle). La question des solidarités au sein du territoire de la Bassée-Voulzie, ainsi qu’entre celui-ci et les territoires aval (et particulièrement la métropole parisienne), nourrit depuis longtemps des frustrations liées à l’exploitation des ressources en eau et en sédiments et à l’aménagement consécutif des milieux aquatiques. En analysant quelques unes des scènes au sein desquelles des acteurs pluriels se rencontrent et confrontent leur vision du territoire, nous mettons en lumière la manière se négocient des projets à des échelles allant du bassin amont de la Seine au bras de rivière ou au plan d’eau et jusqu’à quel point ces négociations multiples offrent une perspective de gestion commune et environnementale du fleuve