HAL Université de Toulouse, et Toulouse INP
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Hétérogénéité spatiale et traits de vie associés aux déclins piscicoles en France
No full textInternational audienceUnderstanding the population dynamics of aquatic species and how inter-specific variation in demographic and life history traits influence population dynamics is crucial to define their conservation status and design appropriate protection measures. The abundance and biomass growth rates for 18 common European freshwater fish species were estimated using data spanning 1990–2011 for 546 sites across France. Spatial heterogeneity in abundance and biomass trends across France were assessed and correlations with life history traits were investigated.Amongst the 18 species, eleven of them have exhibited a significant decline in abundance and 14 species declined in biomass, seven remained stable or exhibited positive abundance growth rates; for four species, biomass was stable or increased. The main declines were observed in the Adour-Garonne and Loire-Bretagne RBDs, where management and conservation measures are urgently needed to halt the erosion of freshwater fish populations. In each of the 5 investigated RBDs, our results highlight areas where most of the common species we studied exhibited negative population growth rates. Of the demographic and ecological traits investigated, life-history strategy and maximum length were significantly correlated with species’ population growth rates, revealing that the decline mainly concerned large-bodied species with slow life-histories. These results focus on 18 common European species representing 94% of fish captured during the study period within the French national monitoring programme and underline that more attention should be paid to the decline in common species.La compréhension des dynamiques démographiques des espèces aquatiques et la compréhension des variations interspécifiques en fonction des traits écologiques et démographiques est crucial pour définir leur statut de conservation et élaborer des mesures de protection appropriées. Les taux de croissance en abondance et de biomasse pour 18 espèces de poissons d'eau douce communes en France ont été estimés à l'aide de données de pêches électriques issues des programmes de biosurveillance depuis 1990. L'hétérogénéité spatiale des tendances temporelles d'abondance et de biomasse à travers les différents bassins hydrographiques français a été évaluée pour les 18 espèces, ainsi que les corrélations avec les traits démographiques des espèces. Onze des 18 espèces étudiées ont montré une baisse significative de l'abondance et 14 ont décliné en termes de biomasse ; sept sont restées stables ou ont connu une croissance positive de l'abondance. Les principaux déclins ont été observés dans les bassins Adour-Garonne et Loire-Bretagne, où des mesures de gestion et de conservation sont nécessaires urgemment pour stopper l'érosion des populations piscicoles. Dans chacun des 5 bassins hydrographiques, nos résultats mettent en évidence des zones où la plupart des espèces communes étudiées ont montré des déclins significatifs. Parmi les traits démographiques et écologiques examinés, la stratégie de vie et la longueur maximale étaient significativement corrélées aux taux de croissance démographique des espèces, révélant que la baisse concernait principalement les espèces de grande taille à faible renouvellement des générations
Improving Near-Field Probe Calibration Technique for Immunity Tests at PCB Level
No full textInternational audienceNear-field scan immunity (NFSI) enables localised and controlled field injection, making it a powerful technique for assessing the vulnerability of electronic components to radio frequency directed energy weapons (RF DEW). However, the lack of rigorous probe calibration methods currently limits its use to qualitative analysis. This paper introduces a complete calibration workflow for electric and magnetic near-field (NF) injection probes, based on the equivalent dipole assumption. The method quantifies both the main and parasitic field components and establishes the spatial and frequency range over which the dipole model remains valid. This characterisation enables the quantitative prediction of field-to-line coupling, through simulation or analytical models, when the properties of the trace and the component impedance are known. The proposed approach provides a necessary foundation for making NFSI a quantitative tool for immunity analysis. Experimental validations on various probes and PCB traces support the methodology and demonstrate its practical relevance
Quasiparticle band picture bridging topology and strong correlations across energy scales
No full textUnderstanding the interplay between electronic correlations and band topology remains a central challenge in condensed matter physics, primarily hindered by a language mismatch problem. While band topology is naturally formulated within a single-particle band theory, strong correlations typically elude such an effective one-body description. In this work, we bridge this gap leveraging the ghost Gutzwiller (gGut) variational embedding framework, which introduces auxiliary quasiparticle degrees of freedom to recover an effective band structure description of strongly correlated systems. This approach enables an interpretable and computationally efficient treatment of correlated topological phases, resulting in energy- and momentum-resolved topological features that are directly comparable with experimental spectra. We exemplify the advantages of this framework through a detailed study of the interacting Bernevig-Hughes-Zhang model. Not only does the gGut description reproduce established results, but it also reveals previously inaccessible aspects: most notably, the emergence of topologically nontrivial Hubbard bands hosting their own edge states, as well as possible ways to manipulate these through a finite magnetization. These results position the gGut framework as a promising tool for the predictive modeling of correlated topological materials
From beams to plates: a new Macro-Element for the simplified analysis of bonded joints
No full textInternational audienc
A comprehensive review and benchmark of differential analysis tools for Hi-C data
No full textInternational audienceThe three-dimensional conformation of the genome has a key role in multiple biological processes such as gene expression regulation. Hi-C is a sequencing technique used to profile 3D chromosomal conformation. The data are summarized in a symmetric matrix, where each pixel (i,j) (or (j,i)) represents the interaction frequency between genomic positions i and j, estimating their spatial proximity. The objective of Hi-C data differential analysis is to identify genomic regions that display significant changes of interactions between two biological conditions. Several tools have been proposed to address this question and most propose to test each pixel of the matrix independently. Here, we present a review and a thorough statistical benchmark of these tools. We first focused on describing the tools on multiple aspects. First, we gave a technical description of the tools' implementations, specifically of their usability. Then, we focused on a statistical description, highlighting the different preprocessings, modelling choices (replicates and covariates, spatial dependency awareness, etc.) and multiple testing corrections proposed. In a second part, we performed an evaluation of the tools on simulations based on real data (mimicking a H0 and a H1 settings with no and controlled signal respectively), which led us to assess proper control of the Type-I error and power of the tools. Then, we evaluated tools to recover biological signal on a auxin/no auxin dataset validated through CTCF external data.Our experiments highlighted the strong impact of data preprocessings, the fact that tools did not control the FDR, and showed the superiority of diffHic
Development of in-house ELISA for Scedosporium/Lomentospora serodiagnosis
No full textInternational audienceScedosporium/Lomentospora species are ubiquitous molds that can cause deep-seated infections and allergic bronchopulmonary mycoses (ABPM). Serodiagnosis is currently performed by immunoprecipitation techniques (IP), which are time-consuming and lack reproducibility. In addition, as antigenic extracts for these fungi are not commercially available, many centers stopped performing this analysis. Therefore, there is a need for automated quantitative alternatives, such as ELISA. The aim of this study was to develop an ELISA for serodiagnosis of Scedosporium/Lomentospora infections. All sera received for Scedosporium/Lomentospora serodiagnosis expertise from April 2022 to February 2024 were tested in parallel using IP and an in-house ELISA with antigenic extracts from both S. apiospermum and L. prolificans. Clinical and biological data such as positive culture, total IgE level and final diagnosis retained were also collected prospectively. The concordance between techniques was calculated, with chi² tests performed to investigate the correlation between ELISA and culture results or final diagnosis. We tested 58 serum samples from 41 different patients. The concordance between IP and ELISA was 64% for S. apiospermum and 62% for L. prolificans. ELISA results obtained with S. apiospermum antigen extract were significantly correlated with culture results (p < 0.001, chi² test). ELISA was also more effective than IP to diagnose ABPM. The Scedosporium/Lomentospora ELISA gave satisfactory results, particularly for S. apiospermum. Further validation on a larger cohort is required implementing this ELISA for routine practice instead of IP. In addition, studies should be conducted on purified native proteins or combination with recombinant antigens to improve standardization
Technologie des capteurs de gaz à semi-conducteurs
No full textGas microsensors are of great industrial interest due to their small size, low consumption, low cost and therefore deployable in a distributed network. Semiconductor gas sensors, although having limited performance compared to analyzers, are among the most commercialized sensors along with electrochemical and optical sensors.This article covers the operation of these sensors, the main materials used (metal oxides) with their detection mechanism as well as the design, manufacturing, characterization and calibration techniques. Current avenues of research around electronic noses and associated perspectives are also discussed.Les microcapteurs de gaz ont un très gros intérêt industriel de par leur faible encombrement, leur faible consommation, leur faible coût, ce qui permet de les déployer en réseau distribué. Les capteurs de gaz à oxydes métalliques semiconducteurs, bien qu’ayant des performances limitées par rapport à des analyseurs, font partie des capteurs les plus commercialisés avec les capteurs électrochimiques et optiques.Cet article couvre le fonctionnement de ces capteurs, les principaux matériaux utilisés avec leur mécanisme de détection, ainsi que les techniques de conception, de fabrication, de caractérisation et d'étalonnage. Sont également abordées les pistes de recherche actuelles autour des nez électroniques, ainsi que les perspectives associées
AN INNOVATIVE ENERGY METHOD TO INFORM SURGICAL PLANNING OF ADOLESCENT IDIOPATHIC SCOLIOSIS
No full textThis abstract was accepted and published in the CMBBE 2025 abstract book. Copyright for this version is held by CMBBE 2025.International audienceDespite the critical role of surgery in managing adolescent idiopathic scoliosis (AIS), the choice of instrumented levels and the sagittal balance remains challenging. We proposed an image-driven energetic model to reduce empiricism. The objective is to simulate the impact of the instrumentation length, ie. the choice of lower and upper instrumented vertebra (LIV and UIV), on the spine response
Observing the Yardang unit at Gale crater on Mars with ChemCam’s RMI
No full textInternational audienceThe Remote Microscopic Imager (RMI) of the ChemCam instrument onboard Curiosity rover provides high-resolution imaging capabilities [1,2]. RMI was first designed to document the LIBS analysis on rocks and soils located at few meters from the rover. RMI progressively proved also to be a powerful long distance imaging reconnaissance tool, thanks to its 700mm focal length. In particular, a new software was uploaded in 2015 to automatically focus up to infinity, a capability which was not implemented in the original design [3]. Since then, RMI has been regularly used to investigate distant various landscapes. Among these, the so-called « Light-toned Yardang unit » [4] was first observed beginning sol 1183 (Figure 1). Several RMI image mosaics acquired up to Sol 1998 helped to identify successive sequences of aeolian deposition-erosion. This is among the youngest sedimentary layers that can be observed in Gale crater with Curiosity cameras. It is interpreted as a succession of fossil aeolian dunes and deflation surfaces [4, 5]. The Yardang unit could result from cyclic changes from semi-arid to arid conditions, including wind regime changes. No hydrated mineral has been detected from orbital imaging spectroscopy. Still, there is interest in finding out the role that water may have played in the induration and diagenesis of the rocks that make up this Yardang unit[5].Between Sols 3671 and 4389, several new long distance RMI mosaics have been acquired while pointing at the base of the Yardang unit. The closer vantage point helps to identify multiple morphologies such as fine-scale layering, wind erosion patterns, or scallops. These features were not accessible nor resolved from orbital imagery only. They could shed light on the formation process of this massive unit. Figure 2 shows an example of a 10800x3200 pixels mosaic corresponding to an assemblage of 60 individual RMI frames which were acquired during three 20x1 sequences between Sols 4384 and 4389.Curiosity has already driven 34 km since the landing in 2012. If Curiosity ever reaches the base of the Yardang unit [6], it would provide the opportunity to sample it directly and reveal its bulk composition, in addition to deriving information from distant geomorphological investigations