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Leptospira prevalence and lineages vary across land-use types due to shifts in small mammal communities
No full textInternational audienceHuman-induced land-use change can affect the composition of small mammal communities and the ecology of their zoonotic pathogens -yet questions remain on the direction and generality of these changes, which can have opposite effects on disease prevalence depending on the ecological context and pathogen involved. These contrasting patterns highlight the need to investigate how specific host-pathogen assemblages respond to local anthropogenic land-use mosaics. To address this need, we studied terrestrial and bat species composition, Leptospira infection prevalence, and Leptospira species composition across a mosaic of land-use types in northeastern Madagascar. We found differences in host communities between forested, agricultural, and village land-use types for both bat (n = 400) and terrestrial (n = 2,053) small mammal communities. Leptospira infection prevalence was higher in bats (37.7%) than in terrestrial small mammals (13.8%), and bats were infected with Leptospira strains that were molecularly distinct from those shed by terrestrial small mammals. Non-native mice and rats were almost exclusively infected with cosmopolitan L. kirschneri and L. interrogans, respectively, while some native terrestrial small mammals sheltered L. mayottensis, and bats hosted a more diverse set of Leptospira species. Leptospira prevalence across land-use types varied in terrestrial small mammals, but not in bats. Altogether, the highest prevalence occurred in mice in flooded rice fields. Our data show that land use predominantly impacts Leptospira infecting terrestrial mammals, likely due to habitat disturbance favoring replacement of endemic hosts and pathogens with Muridae rodents and their associated pathogens, many of which are zoonotic. IMPORTANCE Leptospirosis, a globally distributed, environmentally transmitted zoonosis, causes 2.9 million disability-adjusted life years annually, primarily among rural farmers in tropical regions. Infected animals' urine contaminates soils and water with Leptospira bacteria, where other individuals are then exposed. Understanding the impact of land use on the transmission of this disease is of considerable importance. In Madagascar, infection dynamics are impacted by the combined effects of converting forests to agricultural fields and colonization of these areas by non-native mammal species, which carry molecularly distinct lineages of Leptospira. We show that land use corresponds to the replacement of native species and endemic Leptospira lineages with non-native species and their cosmopolitan L. interrogans and L. kirschneri. Together, this contributes to higher infection prevalence in more disturbed habitats like flooded rice fields, where >50% of mice captured were infected, highlighting the important effects of land use on Leptospira prevalence and presence, which together impact zoonotic risk
First report of cassava mosaic disease in association with East African cassava mosaic Cameroon virus and East African cassava mosaic virus Ugandan strain in cassava in Senegal
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616574/) * Autres projets (id;sigle;titre): ;TSARA;(FRA) Transformer les systèmes alimentaires et l'agriculture par la recherche en partenariat avec l'Afrique//International audienc
Sweat sodium composition and sweat loss estimation through wearable sensors and predictive equations in dry and humid hot conditions
No full textInternational audienceIntroduction: Individualized sweat testing is essential for tailoring hydration and nutrition strategies, as water and sodium losses during exercise vary greatly across athletes. The validity of a wearable sweat sensor (S1, Flowbio) and a handheld analyzer (LAQUAtwin, Horiba Advanced Techno) for measuring sweat sodium concentration ([Na + ]) was tested against flame photometry (FP). Additionally, whole body sweat loss (WBSL) estimated by the S1 and by a sweat rate calculator (SRC) was compared to the scale-based method. Methods: Twenty-three recreationally active participants (11 males, 12 females) completed two sessions in hot and dry (40 °C, 36% rh) and hot and humid (30 °C, 81% rh) controlled environmental conditions on a cycling ergometer (74 ± 12 min, 1.9 ± 0.4 W/kg). Participants were instrumented with two S1 sensors and absorbent patches placed on each upper arm. Sweat was extracted from patches to measure [Na + ] with LAQUAtwin and FP. Nude body mass was measured to the nearest 0.005 kg before and after exercise, with fluid intake monitored to determine WBSL. The influence of the method and the condition on the measure of sweat [Na + ] and WBSL was investigated with linear mixed-effects models. Results: The estimated marginal means of sweat [Na + ] in dry conditions for S1 and LAQUAtwin were equivalent (both 53 mmol/L, p = 0.952) and significantly lower than FP (63 mmol, both -10 mmol, p < 0.001). No significant interaction effects were observed between methods and conditions. For WBSL, the S1 estimation (1.479 kg) was not different than the scale measure (1.432 kg, 0.047, p = 0.624) while the SRC estimation (1.202 kg) was significantly lower than the scale and S1 (both p < 0.001), without interactions effects. Conclusion: S1 offers equivalent and more practical collection of sweat [Na + ] compared to the LAQUAtwin during indoor cycling ergometer exercise. However, measurements from both devices should currently be interpreted Frontiers in Physiology 01 frontiersin.org Bandiera et al. 10.3389/fphys.2025.1717275with caution and not considered equivalent to laboratory-grade analyses. Furthermore, S1 is an adequate tool during indoor cycling ergometer exercise to estimate WBSL when scale measurements are impractical, while SRC was found to underestimate fluid loss.</p
Evaluating the NASA MPLNET Rain Masking Algorithm at Goddard Space Flight Center and Barcelona sites: Relevance to EarthCARE Cloud Profiling Radar Validation
No full textInternational audienceWe analyze the volcanic plume from the April 2015 Calbuco eruption over a 35‐day period using simulations from Meso‐NH, a non‐hydrostatic mesoscale atmospheric model. A dedicated parameterization of the deep injection of the plume into the stratosphere ensures a realistic representation when compared to Infrared Atmospheric Sounding Interferometer satellite observations. During the first 12 hr of the eruption, on 22 April 2015, SO 2 mixing ratio reached 29 ppmv between 15 and 18 km for the first eruption pulse, and 38 ppmv between 12 and 16 km for the second. Most SO 2 was injected directly into the stratosphere, with a stratospheric load reaching 308 ktS (kilotons of atomic sulfur, i.e. 616 kilotons of SO 2 ) after the eruption. After 1 month, both stratospheric and tropospheric SO 2 loads returned to near‐background levels. During analysis, the chemical conversion of SO 2 into H 2 SO 4 removed a part of SO 2 from the stratosphere. During the long‐range advection, the co‐location between the subtropical jet stream and the Calbuco plume led to three significant stratospheric intrusions on 24, 26 and 28 April 2015. These events transferred stratospheric SO 2 into the troposphere, SO 2 mixing ratios in the upper troposphere reaching 15 ppmv, 26 and 15 ppbv, respectively. SO 2 is gradually oxidized into H 2 SO 4 , with up to 5 ktS of gaseous H 2 SO 4 in the stratosphere on 30 April, but dynamical processes dominate the SO 2 atmospheric budget over chemical transformations. This study demonstrates that stratospheric intrusions can play a critical role in the removal of volcanic material from the stratosphere following a major eruption
Characterizing the magnetic signal generated in the magnetosphere from 1996 to 2024 using ground geomagnetic data
No full textInternational audienceThe geomagnetic field, as observed at the Earth’s surface or LEO satellite altitudes (between 300 km and 800 km), is the combination of signals generated by various internal and external sources. The internal sources are mainly associated with the liquid outer core flow, magnetized rocks in the lithosphere and induced electric currents in the crust and mantle. External sources are electric currents flowing in the ionosphere and magnetosphere. We focus on the contributions from the magnetospheric fields and describe a modeling approach in Spherical Harmonics (SH) based on magnetic observatory vector field measurements. The aim of this study is to model the magnetospheric field contributions observed during geomagnetically quiet time up to SH degree 6, with a 1-h temporal resolution for the period covering years 1996.0–2024.8. The adopted modeling approach is based on the Kalman filter and the correlation-based technique, which leads to series of hourly snapshot models together with robust error estimates. The series of models in time compare well with the global magnetospheric Ring Current index (RC). We observed and described various magnetospheric field structures, including local time asymmetries and contributions from ring and magnetotail currents. We also examined annual, semi-annual, monthly and daily variations in magnetospheric field Gauss coefficients in the Fourier domain
Earth’s rotation perturbation by gravitational waves from compact binaries
No full textInternational audienceGravitational waves (GWs) are ripples in space-time that propagate deformations caused by compact bodies throughout the Universe. As an elastic body, the Earth responds to passing GWs much like a resonant sphere. This interaction produces a redistribution of mass, which results in perturbations of the Earth’s tensor of inertia. By conservation of angular momentum, such perturbations lead to a displacement of the rotation axis within the mantle (polar motion) and to changes in the spin rate, directly linked to variations in the length of day (LOD). In this work, we compute for the first time the perturbations of the Earth’s rotation induced by GWs emitted by compact white-dwarf binaries, using a normal mode summation approach applied to an elliptical, rotating, radially stratified Earth model. Our results indicate maximal amplitudes of approximately 10-15μs in the LOD and 10-15 mas for the polar motion—values that remain far below current instrumental sensitivities. These findings highlight the extreme difficulty of detecting GWs through their rotational effects on the Earth, yet the methodology developed here offers a framework that could be extended to other astrophysical bodies
L'IRRESPONSABILITÉ DU BANQUIER DÉCLARANT DE BONNE FOI EN ZONE CEMAC
No full textInternational audienceThe responsibility of bankers in the fight against money laundering and terrorist financing (AML/CFT) is well established, given the challenges posed by globalisation and the ever-increasing diversification of banking transactions. Faced with this situation, bankers must, at the risk of incurring the penalties provided for by regulations, adopt a set of behaviours and habits aimed at preserving not only the interests of their customers but also their image as banking agents and the image of the bank as an institution. That said, there are cases where bankers will not be held liable, particularly when it can be shown that they acted in good faith. It is in this context that the concept of non-liability for bankers acting in good faith has been established. This non-liability is reflected in a set of legal and regulatory mechanisms that have been put in place, but it also has a number of significant consequences that could disrupt the relationship between the bank and its customer. Keywords: Irresponsibility – Regulation – banker – money laundering – terrorist financing.La responsabilité du banquier en matière de lutte contre le blanchiment des capitaux le financement du terrorisme LBC/FT n'est plus à démontrer au regard des enjeux liés à la mondialisation et à l'évolution sans cesse croissante des transactions bancaires de plus en plus diversifiées. Face à cette situation, le banquier se doit, au risque de subir les sanctions prévues par la réglementation, d'adopter un ensemble de comportements et d'habitudes qui auraient pour but de préserver non seulement l'intérêt de sa clientèle mais aussi son image en tant qu'agent d'opération de banque et l'image de la banque en tant qu'Institution. Ceci dit, il existe des cas où le banquier ne verra pas sa responsabilité engagée notamment lorsqu'il est démontré que ce dernier a agi de bonne foi. Cette dans cette perspective que la notion d'irresponsabilité du banquier déclarant de bonne foi est consacrée. Cette irresponsabilité se matérialise par un ensemble de mécanisme juridiques et règlementaire mis en place mais aussi abouti à un ensemble de conséquences non négligeables qui pourraient perturber la relation qui existe entre la banque et son client.</div
Le passage à l'an 2026
No full textInternational audienceGueule de bois pour la fin des gobelets en plastiqu
MiCoReCa (Microbiome Community Resource Catalogue) - Towards Centralized Curation And Integration Of Microbiome Bioinformatics Resources
No full textThe rapid growth of microbiome research has led to the development of numerous bioinformatics tools and databases, but information about them remains fragmented across disparate, often outdated cataloging efforts, hindering resource discovery and utilization. To address this critical gap, the ELIXIR Microbiome Community proposes the development of MiCoReCa (Microbiome Community Resource Catalogue), a comprehensive, dynamic, open-access catalogue of microbiome-related bioinformatics resources (tools, workflows, training, standards, and databases). Leveraging our community's expertise, this initiative will utilize standardized ontologies like EDAM and cross-reference established platforms like bio.tools and WorkflowHub to create a centralized, findable inventory. A key feature is the community-driven process for identifying and curating missing ontological terms and metadata, ensuring MiCoReCa's accuracy and relevance in collaboration with partner platforms. Furthermore, the catalogue will integrate links to training materials from TeSS to support appropriate tool usage, and connect with OpenEBench for benchmarking capabilities. This project will not only provide a vital resource for the microbiome field, enhancing research efficiency and reproducibility, but will also establish a sustainable, adaptable infrastructure potentially applicable to other ELIXIR Communities. This effort represents a significant contribution by the ELIXIR Microbiome Community to streamline microbiome bioinformatics
Zero-inflated binary Tree Pólya splitting regression for multivariate count data
No full textSpecies distribution models (SDMs) are widely used to assess the effects of environmental factors on speciesdistributions. However, classical SDMs ignore inter-species dependencies. Multivariate SDMs (MSDMs), especially those basedon latent Gaussian fields such as the multivariate Poisson log-normal (MPLN), address this limitation but face challengesrelated to computation, dimensionality, and interpretability. Pólya-splitting (PS) distributions offer an alternative, combininga model for total abundance with a multivariate allocation structure, and have natural interpretations from ecological processmodels. Yet, they lack flexibility in modeling correlation structures. Tree Pólya-splitting (TPS) distributions overcome thisby introducing hierarchical structure such as a phylogenetic tree. In this paper, we extend TPS to account for zero-inflation,leading to the zero-inflated tree Pólya-splitting (Z-TPS) family. We detail its statistical properties, show how standard softwareenables efficient inference, and illustrate its ecological relevance using tree abundance data from over 180 genera across theCongo Basin tropical rainfores