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Imagerie CARS multiplexée pour la discrimination sans marquage des protéines musculaires
No full textNational audienceDepuis les années 80, de nombreuses stratégies d’optiques non linéaire ont été développées pour imager des cibles issues du vivant. On peut notamment citer la fluorescence biphotonique [Denk 1990, Denk 1995, Hamzeh 2015, Fischer 2016, Delmon 2023] basée sur un marquage externe des protéines d’intérêt, ou la génération de seconde harmonique (SHG) qui permet la détection sans marquage de protéines uniquement non centrosymétriques [Freund 1986, Aghigh 2023]
Impact of chlordecone pollution on biodiversity: The blind spot of 15 years of public policy in the French West Indies
No full textInternational audienceFor many years, there has been an unprecedented decline in biodiversity on a global scale, triggered largely by the use of plant protection products. In this context, a collective scientific assessment was conducted to identify current consensus knowledge and further needs regarding the impacts of plant protection products on biodiversity and ecosystem services in France, including its overseas territories. A particular focus was placed on chlordecone, a highly persistent organochlorine insecticide used extensively in the French West Indies (FWI) for more than 20 years (1972-1993) to control the banana root borer, but also in Eastern Europe, the USA, South America and Africa for various uses. The FWI support biodiversity hotspots, with many endemic and endangered species, and include marine and terrestrial protected areas. Such an environmental context is therefore highly relevant for studying the links between chlordecone contamination and potential effects on biodiversity. Thus, the objective of this work was to review the contamination of the FWI environment by chlordecone, its transfer through ecosystems, and its effects on biodiversity and ecosystem services. Literature analysis emphasized valuable knowledge of chlordecone ecodynamics in terrestrial, freshwater, and marine ecosystems. A wide diversity of terrestrial and aquatic organisms is chronically exposed to chlordecone. However, despite 15 years of public policy dedicated to developing knowledge on chlordecone’s fate and impacts, the knowledge gap remains critical regarding its effects on biodiversity and on ecosystem services. As the local environment is often contaminated for tens or even hundreds of years, future research is needed to characterize the effects of legacy pollution by chlordecone and its transformation products on organisms and ecosystems
Effects of host sex, age and behaviour on co-infection patterns in a wild ungulate
No full textInternational audienceRecent zoonotic disease emergences emphasize the importance of studying wildlife parasite communities. As wild hosts frequently harbour diverse parasite species, understanding the drivers of multiple infection patterns in free-ranging hosts is critical for elucidating the ecological and epidemiological dynamics of parasite communities. In this study, we analysed co-infection patterns in European roe deer (Capreolus capreolus) inhabiting a fragmented rural landscape in southwestern France. Using data from 130 samples of GPS-tracked deer, we examined the influence of proximity to livestock, host activity levels, age, sex, and between-parasite interactions on the presence of 11 parasitic taxa. Hierarchical modelling of species communities (HMSC) revealed that proximity to livestock significantly increased the likelihood of infection with orofecally transmitted parasites (Toxoplasma gondii, gastrointestinal parasites). Sex and age were other key predictors, with males and juveniles exhibiting a higher frequency of parasite presence, likely influenced by hormonal and immune system differences. Activity levels showed distinct age-related effects, with higher activity levels being positively associated with increased parasite prevalence in yearlings, but not in adults. In contrast, parasite association patterns within individual hosts were weak, suggesting minimal interactions between parasite species. Our findings highlight the interplay between exposure and susceptibility in shaping co-infection patterns and underscore the value of hierarchical modelling approaches in multi-parasite systems
Animation scientifique
No full textInternational audienceCe séminaire a permis à 9 auteur.e.s de dialoguer autour de leurs contributions. 4ème de couverture du livre : La médiation artistique est à l’origine de multiples expériences thérapeutiques. Dans un espace éducatif, toute rencontre esthétique, démarche pédagogique ou pratique créative transforme le rapport à soi, à l’autre, et l’appartenance au monde. La mise en perspective de regards multiples et croisés est nécessaire pour répondre à une question déterminante : la relation à l’art bénéficie-t-elle au bien-être personnel ? En matière de santé holistique, tout rétablissement dépend de l’impact existentiel de la souffrance. Aussi, est-il nécessaire de repenser l’expérience thérapeutique à la lumière de la subjectivité, des valeurs, des projets de vie des personnes dans les interactions humaines. Cet ouvrage scientifique participe de divers champs et contextes spécifiques aux sciences de l’éducation et de la formation. Il offre des approches contrastées autour du rétablissement, de l’expérimentation artistique et d’une meilleure vie sensible. Il s’inscrit dans le cadre de travaux de recherche menés par des chercheur.es pour la plupart membres de différents laboratoires (CIREL-Proféor et Ceped-IRD pour la coordination de l’ouvrage). Corinne Baujard est professeure des universités en sciences de l’éducation et de la formation (université de Lille, équipe Proféor du laboratoire CIREL EA), docteure de Paris-Dauphine, HDR de Paris Saclay, responsable pédagogique du master Recherche travail éducatif et formation. Carole Baeza est professeure en sciences de l’éducation et de la formation à l’université Sorbonne Paris-Nord et membre du Centre population et développement (CEPED) UMR 196. Francis Danvers est professeur émérite des universités en psychologie et sciences de l’éducation et de la formation à l’université de Lille SHS. Il est membre de l’équipe Proféor du laboratoire CIREL EA. Ont contribué : Marjan Abadie, Carole Baeza, Corinne Baujard, Ingrid Berger, Rémi Casanova, Léa Chabanel-Kahlik, Sylvie Condette, Francis Danvers, Christine Delory-Momberger, Claire Delporte, Christophe Ducrocq, Pierre Johan Laffitte, Nelly Logez-Deschamps, Marie-Lise Lorthiois, Valérie Melin, Luciana Mendes Velloso, Catherine Négroni, Michel Rival, Marie Stoecklin Burr, Cécile Tréton. Illustration de couverture : ©Pexels. ISBN : 978-2-336-52344-6 38 € Sous la direction de Corinne Baujard, Carole Baeza et Francis Danver
Overview of GeoLifeCLEF 2025: Plant Species Presence Prediction with Environmental and High-resolution Remote Sensing Data
No full textInternational audienceGeoLifeCLEF 2025 competition, organized as part of the LifeCLEF and FGVC workshops, challenges participants to predict plant species composition at high spatial resolution across Europe using multimodal environmental data. The task builds on a large-scale dataset that combines 5 million Presence-Only (PO) observations and approximately 100,000 standardized Presence-Absence (PA) surveys, paired with Sentinel-2 imagery, Landsat time series, climate rasters, and soil descriptors. This year's edition introduced two major challenges: a geographically shifted test set with plots from previously unseen regions with different species distribution, thereby including many rare species that are under-reported by citizen scientists. These changes increased the modeling difficulty and emphasized the need for generalization under spatial shift and class imbalance. In this paper, we summarize the task design, dataset characteristics, evaluation protocol, participant approaches, and competition results, and discuss implications for scalable species distribution modeling and biodiversity monitoring
Comparative study of agricultural parcel delineation deep learning methods using satellite images: Validation through parcels complexity
No full textInternational audienceAccurate delineation of agricultural parcels is crucial for applications ranging from resource management to policy decisions, with a direct impact on agricultural productivity and sustainability. Parcel delineation is the subject of numerous studies, most of which focus on the development of more efficient methods or ones better adapted to specific cases. In addition, various methods exist in the literature for delineating agricultural fields from satellite images. Deep learning, in particular, has revolutionized the field. Many state-of-the-art methods now utilize deep learning, often incorporating segmentation and classification techniques to define agricultural parcel boundaries. While recent research has led to a surge in deep learning methods for this task, evaluating their effectiveness goes beyond simply comparing outputs. This paper emphasizes the critical role of parcel complexity as a powerful lens for assessing the performance of deep learning methods in agricultural parcel delineation. We categorize 14 evaluation metrics into three main groups, global, boundary, and structure metrics, respectively. Global metrics assess the overall accuracy of the delineated parcels, boundary metrics focus on the precision of the parcel boundaries, and structure metrics examine the topological relationships between the parcels. Our goal is to compare these deep learning methods based on these metrics and their performance across varying levels of parcel complexity. We systematically evaluate nine state-of-the-art methods using a public database, explicitly analyzing how their strengths and weaknesses are affected by different levels of parcel complexity. This approach ensures that future deep learning techniques are robust and accurate enough to meet the demands of accurately defining the agricultural landscape and provides important insights for the development and refinement of future deep learning techniques
Towards viscous debris flow simulation using DualSPHysics v5.2: internal behaviour of viscous flows and mixtures
No full textInternational audienceAbstract. This paper investigates the accuracy of a solid–fluid model using the smoothed-particle hydrodynamics (SPH) software DualSPHysics v5.2 coupled with ProjectChrono for viscous debris flow modelling. It focuses on different validation steps of the method, both for pure fluid and a mixture of fluid and boulders, to build the reliability of the model in order to prepare for the simulation of a simplified debris flow. First, velocity profiles, the free-surface shape and the velocity of surges of a viscous fluid are validated against well-documented experimental data. This is, to the best of our knowledge, one of the few validations of the SPH approach for very viscous flows near the creeping threshold (Re ≈ 1). Second, the influence on the macroscopic viscosity of the introduction of granular elements in a viscous fluid is studied against a semiempirical formula. Finally, the method is applied to simplified 2D debris flow surges with field-like features. Surges modelled in this paper are composed of a viscous Newtonian fluid and polydisperse boulders. The flow of surges of different concentrations is studied, and Froude numbers of real field measurements are retrieved. Such complex models are shown to be relevant to the study of debris flow dynamics
"Nomad" and "Surface – Air Gas Exchanges" SAGE All-Terrain Chambers Open Access Instrumentation
No full textInternational audienceScientific studies require appropriate instrumentation, and many laboratories build their own instruments. At CESBIO, we have developed both manual and automated accumulation chambers that cater to a wide range of needs. We share these designs with the scientific community
Rockfall Forecasting using Ensemble Deep Learning and Temporal Gradient-Based Explanations
No full textInternational audienceRockfalls pose a significant risk for infrastructures and human activities. Accurate forecasting is therefore crucial for prevention. While current methods rely on expert hypotheses, AI models, particularly explainable ones, offer a promising way to improve the accuracy of forecasts and provide transparent, trustworthy results. In this paper, an ensemble of multisource neural networks based on InceptionTime modules whose forecasts are explained using a temporal Grad-CAM approach is being developed for the Mont Saint-Eynard cliff, showcasing the potential of AI in this area
An Initial Assessment of the Collembola (Hexapoda) Fauna of the Bula Hyrcanian Forest (Iran) at the Interface of Two Biodiversity Hotspots
No full textInternational audienceThe Hyrcanian Forests of northern Iran, a UNESCO World Heritage Site, are renowned for their exceptional biodiversity, hosting numerous relict, threatened, and endemic species. Located at the intersection of the Caucasus and Irano-Anatolian biodiversity hotspots, these forests have been extensively studied for vascular plants, but soil arthropods like springtails (Collembola) remain largely understudied. This study aims to fill this gap by conducting a comprehensive survey of the Collembola fauna in the Bula Forest, Mazandaran Province. Sampling covered various substrates (decaying wood, moss, soil and leaf litter) in three forest types: a UNESCO-listed natural forest, a preserved planted forest, and an unpreserved natural forest. 73 Collembola species, belonging to 39 genera and 12 families were recorded. Pseudachorutes vasylii Kaprus’ & Weiner, 2009, Paranura Axelson, 1902 (Neanuridae) and Pseudanurophorus Stach 1922 (Isotomidae) were documented for the first time in Iran. Drepanura Schött 1891 (Entomobryidae), Pachyotoma Bagnall, 1949 (Isotomidae), Mesaphorura hylophila Rusek, 1982, and Mesaphorura macrochaeta Rusek, 1976 (Tullbergiidae) represent first records for the Hyrcanian Forests. To provide a comprehensive overview of Collembola biodiversity in the Hyrcanian forests, the present analysis of samples collected in Bula Forest was integrated with a thorough review of published records from the provinces of Mazandaran, Gilan and Golestan - all of which encompass significant portions of this ancient forest. This study offers one of the most comprehensive inventories of Collembola in the Bula Forest, providing insights into species distribution across microhabitats. The remarkable Collembola diversity underscores the importance of this region for biodiversity conservation