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A review of the applications of natural FRCM composites
No full textInternational audienceThe vulnerability of structures remains a major concern for various stakeholders, from engineers to users. High strength composite materials have been developed to improve the mechanical performance of existing and new structures. Initially, Fibre Reinforced Polymers (FRP), generally based on carbon fibres, were used. However, due to their many limitations, fabric reinforced mineral matrix composites, also known as Textile Reinforced Mortars (TRM), were developed. These materials, also known as Textile Reinforced Concrete (TRC) or Fabric Reinforced Cementitious Matrix (FRCM), have been investigated as a promising alternative to FRP for the reinforcement of substrates such as concrete and masonry. Mineral matrix composites offer improved substrate compatibility, enhanced mechanical performance at elevated temperatures and reduced construction material costs compared to FRP. In addition, the use of natural fibres (flax, hemp, jute, sisal) in mineral matrices has grown rapidly due to their mechanical properties and lower environmental impact. This paper reviews the use of natural FRCM in the strengthening of structures and in new construction projects, focusing on their mechanical response, bonding to substrates and different strengthening techniques (flexural, shear, confinement). Key parameters influencing the effectiveness of these systems are described in order to optimise future work. The article also compares the advantages of synthetic and natural FRCM and highlights their limitations. While the scientific literature contains studies on the development of natural FRCM, further research is needed to better understand the impact of various parameters on their effectiveness, the durability of the strengthening system and the influence of high temperatures
Altérations des cellules hôtes et multiplication des agents pathogènes dans un modèle d’épithélium intestinal in vitro de co-infection par la microsporidie Encephalitozoon intestinalis et l’entérovirus A71.
No full textInternational audienceLes agents pathogènes intracellulaires sont impliqués dans plusieurs infections intestinales symptomatiques et asymptomatiques. En réorganisant les compartiments de la cellule hôte, ils établissent un microenvironnement qui favorise leur survie et leur réplication. La plupart des études menées jusqu’à présent se sont concentrées sur des modèles de monoinfection, qui ne reflètent pas pleinement la réalité biologique dans laquelle plusieurs agents pathogènes peuvent coexister et interagir au sein de l’environnement intestinal. Cette étude visait à évaluer la pertinence d’un modèle in vitro de barrière intestinale constitué de cellules épithéliales Caco-2 différenciées pour examiner les effets d’une co-infection combinant le microsporidie Encephalitozoon intestinalis et l’entérovirus A71.Un modèle épithélial intestinal commun, permissif pour les deux agents pathogènes, a été développé afin d’optimiser les conditions d’infection. Les infections individuelles par l’un ou l’autre agent ont induit une relocalisation de la protéine des jonctions serrées ZO-1, ainsi qu’une désorganisation du réseau d’actine associée à l’extrusion des cellules infectées hors du monocouche, indiquant une perturbation de l’intégrité épithéliale. Dans des conditions de co-infection séquentielle, cette altération est survenue plus tôt, suggérant une perte synergique de l’intégrité de la barrière résultant de l’action combinée des deux agents.Une diminution du nombre de copies du génome d’EV a été observée lors de la co-infection, suggérant une possible compétition pour la niche intracellulaire. La réponse précoce de l’hôte, évaluée par la production d’interleukine-8, a été détectée pour chaque agent pathogène, sans effet significatif d’une infection microsporidienne préalable sur la réponse à l’infection virale.Dans l’ensemble, ces résultats mettent en évidence une possible compétition entre les deux agents pathogènes pour les ressources cellulaires de l’hôte, influençant en fin de compte la dynamique et l’intégrité de la barrière intestinale
Diversité et dynamique temporelle à long terme des microsporidies dans le lac d'Aydat par une approche de paléogénomique
No full textNational audienceContexte : Les microsporidies sont des parasites intracellulaires obligatoires affiliés aux champignons. Elles infectent une large gamme d'hôtes, allant des protistes aux vertébrés. Malgré leur présence ubiquitaire, une grande partie de leur diversité environnementale et de leurs associations avec les hôtes reste encore méconnue (Chauvet et al. 2022, 2023). Objectif : Explorer la diversité et la dynamique temporelle des microsporidies dans un lac soumis à des pressions anthropiques en utilisant une approche de paléogénomique
A neighborhood for Pickup and Delivery Problem withCooperative Robots
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Origin of the mass-dependent germanium isotopic continuum in the early Solar System
No full textInternational audienceThe warm, reduced, volatile-poor inner Solar System and cold, oxidized, volatile-rich outer Solar System are characterized by neutron-poor and neutron-rich isotopic anomalies, respectively. Nucleosynthetic isotopic anomalies recorded in meteorites, asteroidal bodies, and planets are thus indicative of their regions of formation. However, whether these reservoirs evolved as closed systems or underwent some degree of intermixing remains uncertain. Here, we report new high-precision mass-dependent germanium isotopic compositions revealing that carbonaceous chondrites exhibit higher and more variable d74/70 Ge values than ordinary chondrites, defining a strong continuous trend in both Ge concentrations and isotopic compositions. We highlight that similar strong correlations with matrix mass fraction occur across all chondrite groups, but that the non-carbonaceous (NCC, inner Solar System)-carbonaceous (CC, outer Solar System) dichotomy observed in e 48 Ca, e 54 Cr, e 50 Ti, and e64 Ni nucleosynthetic anomalies is maintained. In the d 74/70 Ge vs. e 48 Ca, e54 Cr, e 50 Ti, and e 64 Ni spaces, two distinct mixing lines are resolved within both the NCC and CC reservoirs, between NCC and CC-type chondrules and CI-type matrix. Extending the NCC-CI chondrite correlation to primitive achondrites, main-group pallasites, and the mantles of Mars and Earth reveals that these silicate reservoirs plot away from the OC-CI mixing lines, highlighting the possible existence of a neutron-poor matrix component in the inner Solar System. Overall, the Ge isotopic systematics of the Solar System suggest that chondrules and their matrices did not form exclusively in a single reservoir, but rather formed throughout the inner and outer Solar System
"Chronique des entreprises et participations publiques (octobre 2024 à octobre 2025)"
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Autisme et droit(s)
No full textInternational audienceSept cent mille personnes touchées par l’autisme en France, et autant de familles concernées : la question peine pourtant à émerger dans le débat public et juridique.Handicap protéiforme et évolutif, les troubles du spectre autistique constituent un défi pour le droit. Quelle éthique exprimer ? Comment concevoir et interpréter la règle ? Comment adapter la société à des formes si particulières d’être au monde ? Que nous dit le quotidien des barrières existantes ?Au-delà des textes en vigueur ou à inventer, juristes, scientifiques et philosophes interrogent ici la présence des droits et libertés ainsi que leur effectivité.Cet ouvrage, centré sur l’enfance et l’éducation, dresse un bilan de plusieurs décennies d’évolution du droit vis-à-vis de l’autisme. Cette approche est d’autant plus utile qu’elle est rare
The ANUBIS detector and its sensitivity to neutral long-lived particles
No full textInternational audienceLong-lived particles (LLPs), i.e., particles with macroscopic lifetimes τ>10~ns, appear in various extensions of the Standard Model (SM) that address fundamental questions like the particulate nature of dark matter or baryogenesis. The ANUBIS detector will achieve unprecedented sensitivity to such models compared to existing and approved experiments by instrumenting a large decay volume adjacent to the ATLAS experiment at the High-Luminosity LHC with tracking detectors. This paper outlines the proposed detector layouts for ANUBIS, explores their physics potential with a scalar LLP model, and identifies the preferred layout, comparing it to other experiments. The potential background contributions to ANUBIS are estimated using a data-driven method, and the topology of potential background events is studied using Monte Carlo simulations. Overall, ANUBIS is expected to probe branching ratios down to (10 for exotic decays of the Higgs boson to scalar long-lived particles with masses of 10, 15, 40, and 60 GeV and proper lifetimes of , and 18 m, respectively. Moreover, for branching ratios of 0.1% of the Higgs boson into long-lived scalars with a mass of 15 GeV, ANUBIS can probe a range between ~m and ~m
Esquilache y el gobierno de la Hacienda real provincial. ¿Una nueva visión de la administración?
No full textInternational audienceThe instruction given on November 10th, 1760, by the Marquis of Esquilache to provincial intendants and administrators has been little studied, although for contemporaries it expressed a novel conception of the role of the provincial administration of the Treasury. I study its genesis, based on a mitigated evaluation of the previous policy of the Marquis of Ensenada, and the meaning its promoters gave to the new ‘method’.La instrucción dada a 10 de noviembre de 1760 por el marqués de Esquilache a intendentes y administradores de provincias ha sido poco estudiada, aunque para los contemporáneos reflejaba una novedosa concepción del papel de la administración provincial de la Hacienda. Estudio su génesis, basada en una evaluación ambivalentede la política previa del marqués de Ensenada, y el significado dado por sus promotores al nuevo «método»
The Viscosity of Albitic Melt at High Pressures and Implications for the Mobility of Crust‐Forming Magmas
No full textco-auteur étrangerInternational audienceThe earliest form of continental crust was produced by tonalite‐trondhjemite‐granodiorite (TTG) magmas. Molten albite (NaAlSi 3 O 8 ) is representative of TTGs and also a major component of modern crust‐forming magma. The viscosity of the melt controls the magma ascent rate and hence influences the production of new continental crust. It is well known that the viscosity ( η ) of albitic melt exhibits an anomalous pressure ( P ) dependence. However, prior results on the melt η at high‐ P differ significantly which limits our ability to predict the movement of crust‐forming magma at depth. In this study, we more tightly constrained the P ‐effect on η in anhydrous albitic melt via high‐ P and high‐temperature ( T ) falling sphere experiments. We limited undesirable drag effects by using small sphere‐to‐capsule diameter ratios ( d / D ) such that d / D ≤ 0.12, and evaluated uncertainties due to such drag using a Monte Carlo approach. Our results show that melt η first decreases with P (i.e., ∂ η /∂ P < 0) and then increases with continued compression (∂ η /∂ P > 0) with a well‐defined η minimum ( η min ) at ∼6 GPa along a ∼2,000 K isotherm. We find that the viscosity of the melt can be described by an Arrhenius formalism with an activation volume that varies with P and T . The results indicate that η of aluminosilicate magmas decrease with depth and temperature in the crust, thereby mobilizing the magmas to promote rapid volcanic eruptions. The results also suggest that TTG magmas relevant for the early Earth could pond during ascent due to the anomalous P ‐effect on η