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An active ensemble classifier for detecting animal sequences from global camera trap data
No full textInternational audienceAbstract Camera traps can generate huge amounts of images, and thus reliable methods for their automated processing are in high demand: in particular to find those images or image sequences that actually include animals. Automatically filtering out images that are empty or contain humans can be challenging, as images can be taken in different landscapes, habitats and light. Weather and seasonal conditions can vary greatly. Most of the images can be empty, because cameras using passive infrared sensors (PIR) trigger easily due to moving vegetation or rapidly varying shadows and sunny spots. Animals in images are often hiding behind vegetation, and camera traps will see them from previously unseen angles. Therefore, conventional animal image detection methods based on deep learning need huge training sets to achieve good accuracy. We present a novel background removal approach based on movement masked images computed using sequences of images. Our deep vision classifier uses these movement images for classification instead of the original images. Additionally, we apply a deep active learning (active learning for deep models) for collecting training samples to reduce the number of annotations required from the user. Our method performed well in singling out image sequences that actually include animals, thus filtering out the majority of images that were empty or contained humans. Most importantly, the method performed well also for backgrounds and animal species not seen in the training data. Active learning brought good separation between classes already with small training sets, without the need for laborious large‐scale pre‐annotation. We present a reliable and efficient method for filtering out empty image sequences and sequences containing humans. This greatly facilitates camera trapping research by enabling researchers to restrict the task of animal classification to only those image sequences that actually contain animals
The mitogenome of the Northern Hemisphere native terrestrial flatworm Rhynchodemus sylvaticus (Leidy, 1851) (Platyhelminthes, Geoplanidae)
No full textInternational audienceRhynchodemus sylvaticus (Leidy, 1851) is a tiny terrestrial flatworm of the subfamily Rhynchodeminae (Platyhelminthes, Geoplanidae) generally found in Europe and North America. Its mitogenome is 16,891 bp long, contains 12 protein-coding genes, two rRNA genes and 21 tRNA genes. No tRNA-Thr was found, ND6 starts with ATT, cob is longer at its 3’ ending. Unlike the other eight species of Rhynchodeminae with sequenced mitogenomes, there is a real stop codon for ND5. Also, the position of tRNA-Met differs. Multiprotein phylogeny shows R. sylvaticus within a clade including species of the tribe Rhynchodemini from Oceania, but distinguished by a long branch
One Spiking Neuron Classification Based on Kolmogorov Complexity
No full textInternational audienceThis paper investigates the potential of a minimalist spiking neural network for digit recognition tasks, using the MNIST dataset as a benchmark.The proposed model features a single spiking neuron utilizing the Izhikevich neuronal model, deliberately crafted without weights or a learning phase, embodying the minimalist approach of maximizing performance with minimal resources.Our approach integrates self-organizing maps with a novel optimization method for cluster selection, leveraging Kolmogorov complexity and prototype abstraction. The model achieves notable performance for digits with distinct visual structures, such as digit one (1), with 99% accuracy. We evaluated the model's generalization on a Roman numeral dataset from EMNIST, showing improved performance on simpler, angular patterns. This confirms the model's suitability for regular inputs and highlights the potential of minimalist spiking architectures for future neuromorphic models
Imagerie des structures internes d’un glissement de terrain par une approche couplée gravimétrie-tomographie de résistivité électrique.
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multistrap: boosting phylogenetic analyses with structural information
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Le faaapu : prendre soin de sa terre, prendre soin de soi.: Le jardinage comme stratégie de « résistance par la subsistance »
No full textInternational audienceLes îles du Pacifique et notamment la Polynésie française ont régulièrement été confrontées à des perturbations environnementales causées par des événements météorologiques parfois violents. Les agriculteurs et habitants qui cultivent des produits alimentaires sont particulièrement exposés à ces évènements et ont déployé une « culture du risque » (David 2004; Magnan, Duvat, et Garnier 2012). Par exemple, ils ont développé certains pratiques d’adaptation aux effets du changement climatique (paillage, variation des types de cultures et de plantation…), notamment par l’hybridation des savoirs (savoirs transmis, savoirs institutionnels, savoirs enseignés…). Ce sont particulièrement ces savoirs locaux et leur hybridation et circulation que nous étudions dans le cadre du projet CLIPSSA (Climat du Pacifique, Savoirs locaux et Stratégies d’Adaptation). A cette fin, notre équipe composée d’anthropologues, ethnoécologues, géographes et agronomes (chercheurs et stagiaires) a mené 57 entretiens avec des agriculteurs de Tahiti et de Moorea entre 2024 et 2025, dont une trentaine cultivent à une petite échelle (quelques dizaines de m2).Les adaptations au changement climatique sont largement répandues mais diffèrent grandement d’un type de production à un autre. Les problématiques météorologiques rencontrées (vents, sécheresse, fortes pluies…), les enjeux de la production (produire pour se nourrir, pour avoir un revenu…) ou encore les ressources mobilisées (réseau familial, professionnel, niveau d’équipement, capacité d’investissement…) ne sont pas les mêmes pour une personne qui cultive du vivrier et du maraichage sur quelques dizaines de m2 que pour un agriculteur qui combine maraichage, arboriculture et élevage sur plusieurs hectares. Nous proposons dans le cadre du colloque « l’alimentation en Océanie » d'interroger les différentes fonctions nourricières des faaapu (jardins potagers) de Tahiti et de Moorea, en considérant tant les dimensions alimentaires, que celles sociales, culturelles et spirituelles. Le faaapu est en effet au cœur de stratégies économiques de sobriété des habitants, visant d’abord à réduire les dépenses alimentaires. Mais nous verrons également que les faaapu occupent de nombreuses fonctions : sociale (créer du lien, échanger avec sa famille, ses amis), esthétique (embellir son environnement domestique), de loisir voire de soin ((s’)occuper (de) son corps et son esprit, estime de soi…). Ainsi, cultiver des produits alimentaires dans son faaapu est une forme de « Résistance par la subsistance » (Rainville 2025), il ne s’agit pas seulement de « faire sans » (avec des ressources limitées, un foncier réduit…), mais de « faire avec » (avec ce qu’on possède, ou ce qu’on peut mobiliser). Il s’agit d’une forme de « résistance ordinaire » ancrée dans la vie quotidienne (Dobré 2002), qui peut, dans une certaine mesure, être assimilée à une forme de mobilisation écologique (Pruvost 2025)
CONSTRUIR A PAZ COM O VIVO: UMA PERSPECTIVA JURÍDICO-ANTROPOLÓGICA DA JUSTIÇA TRANSICIONAL
No full textAlice BRITES OSORIO. Faire la paix avec le vivant: une perspective juridico-anthropologique de la justice transitionnelle. Università degli Studi di Trento. Grandi transizioni, vulnerabilità e ruolo del diritto = Les grandes transitions, vulnérabilités et rôle du droit, IRIS, 2025, 978-88-5541-123-3. ⟨10.15168/11572_463217⟩. ⟨hal-05304557
EPR Dating of Clay Minerals Formation Through Geological Times: Benchmarking From the Quaternary to the Neoproterozoic Era
No full textInternational audienceRevealing the environment and timing of clay formation in the geosphere is of major importance to understand and model the evolution of geological systems at the surface or near-surface of the continents, such as weathering covers, sedimentary basins or hydrothermal systems. Dating clay minerals by electron paramagnetic resonance spectroscopy (EPR) is a promising method that relies on the measurement of stable radiation-induced defects (RIDs) accumulating in their structure over time due to natural radioactivity. This approach has not yet been challenged by the inter-comparison with other geochronological methods, mostly because clay minerals accurately dated with methods independent from the EPR approach and also suitable for the EPR dating remain scarce in the geological record. Herein, an up-to-date protocol for the EPR dating and benchmarking are provided and developed by analyzing selected clay samples. The series includes a Mesoproterozoic illite (Thelon Basin, Canada), two paleosol kaolinites (Ukraine, Estonia) from at least late Ediacaran period, an Ypresian sedimentary kaolinite from the Aquitan Basin (France) and two Miocene and Pliocene kaolinites from lateritic duricrusts (Amazonia, Brazil). Despite some discussed uncertainties mainly related to the Th distribution in the samples, the time variation of dose rate and the thermal history of some clay samples, the EPR ages show a trend close to the 1/1 line with ages determined by other dating methods. These results bring promising support to the EPR dating methodology of clay minerals and extend its potential application field over a time-range spanning from Quaternary to Proterozoic
European mammal turnover driven by a global rapid warming event preceding the Paleocene–Eocene Thermal Maximum
No full textInternational audienceA brief global warming event known as the Pre-Onset Excursion (POE) occurred just before the Paleocene–Eocene Thermal Maximum (PETM, 56 Mya). The deconvolution of the evolutionary consequences of these two hyperthermal events is puzzling because of their close temporal proximity and the lack of comprehensive, well-calibrated paleontological records, especially in terrestrial environments. As a consequence, the impact of the POE on mammalian evolution and its role in shaping PETM faunas remains unclear. Here, we report from France a mammalian fauna, named Albas, which is interpreted to postdate the POE and predate the PETM. The absence of artiodactyls, perissodactyls, and euprimates at Albas lends support to the controversial hypothesis that these “modern” mammal groups appeared in the European fossil record during the PETM. In contrast, Albas yielded the European first definitive Paleocene record of metatherians, paromomyid primates, “creodonts,” and rodents, challenging the assumption that these groups migrated into Europe during the PETM. Because the majority of them originated from North American pre-POE species, we tentatively suggest that these “precursor” dispersers entered Europe during the POE. Similar to the modern orders during the PETM, these “precursor” dispersers likely entered Europe through corridors in the continuous evergreen forest belt at high latitudes. Our findings highlight how a brief warming event in the Arctic during the latest Paleocene, such as the POE (which could result in a release of carbon into the atmosphere similar to cumulative ongoing anthropogenic emissions), significantly influenced the evolutionary dynamics of European mammals
Papillomavirus humains (HPV) et dépistage du cancer du col de l’utérus : état des lieux des connaissances des femmes guadeloupéennes en 2025
No full textIntroduction: Currently in France, there are two ways to prevent cervical cancer: vaccination against human papillomavirus (HPV) and screening through Pap smears. Guadeloupe is among the regions with the lowest cervical cancer screening coverage (44.5%). This low participation may be explained by a lack of awareness and information. Objectives: To assess the level of knowledge among Guadeloupean women regarding cervical cancer screening and HPV. Materials and Methods: A quantitative, observational, descriptive, multicenter study was conducted in 7 general practice clinics in Guadeloupe. Data were collected using an anonymous self-administered questionnaire distributed to patients. Knowledge of CCU screening and HPV was evaluated using a scoring system. Results: Most patients had a moderate knowledge score, 11% had a low score, and 19% had a high score. 23% mistakenly believed HPV infection is rare, and 45% thought condoms offer full protection. Only 19% knew HPV could also cause throat or penile cancer. Many confused Pap smears with vaginal swabs for STIs (54%), yeast infections, or bacterial vaginosis (48%). Conclusion: This study highlights a lack of knowledge about HPV and cervical cancer screening in the Guadeloupean population. It emphasizes the key role of general practitioners and calls for concrete actions to improve prevention.Introduction : Actuellement en France, il existe deux moyens de prévention contre le cancer du col de l’utérus : la vaccination contre le papillomavirus et le dépistage par frottis cervico-utérin. La Guadeloupe fait partie des régions avec le taux de couverture de dépistage du CCU le plus faible (44,5%). Cette non-participation pourrait s’expliquer par un manque de sensibilisation et d’information. Objectifs : Réaliser un état des lieux des connaissances des femmes guadeloupéennes sur le dépistage du cancer du col de l’utérus et le papillomavirus. Matériel et méthodes : Étude quantitative, observationnelle, descriptive, multicentrique dans 7 cabinets de médecine générale en Guadeloupe. Le recueil des données s’est fait par auto-questionnaire anonyme distribué aux patientes. Les connaissances sur le dépistage du CCU et le virus HPV ont été évaluées à l’aide d’un score. Résultats : La majorité des patientes ont obtenu un score de connaissance modéré, 11 % un score faible et 19 % un bon score. 23 % pensent à tort que l’infection à HPV est rare, et 45 % que le préservatif protège totalement. 19 % savent que le HPV peut aussi provoquer un cancer de la gorge ou du pénis. Beaucoup confondent le frottis avec un prélèvement pour IST (54 %), mycose ou vaginose (48 %). Conclusion : L’étude met en évidence un manque de connaissances sur le HPV et le dépistage du CCU. Elle souligne le rôle clé des généralistes et appelle à des actions concrètes