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Les petites mains des pieds : un atelier de chaussures dans les années 1950
No full textNational audienc
Euclid preparation: Extracting physical parameters from galaxies with machine learning
No full textInternational audienceThe Euclid mission is generating a vast amount of imaging data in four broadband filters at high angular resolution. This will allow the detailed study of mass, metallicity, and stellar populations across galaxies, which will constrain their formation and evolutionary pathways. Transforming the Euclid imaging for large samples of galaxies into maps of physical parameters in an efficient and reliable manner is an outstanding challenge. We investigate the power and reliability of machine learning techniques to extract the distribution of physical parameters within well-resolved galaxies. We focus on estimating stellar mass surface density, mass-averaged stellar metallicity and age. We generate noise-free, synthetic high-resolution imaging data in the Euclid photometric bands for a set of 1154 galaxies from the TNG50 cosmological simulation. The images are generated with the SKIRT radiative transfer code, taking into account the complex 3D distribution of stellar populations and interstellar dust attenuation. We use a machine learning framework to map the idealised mock observational data to the physical parameters on a pixel-by-pixel basis. We find that stellar mass surface density can be accurately recovered with a scatter. Conversely, stellar metallicity and age estimates are, as expected, less robust, but still contain significant information which originates from underlying correlations at a sub-kpc scale between stellar mass surface density and stellar population properties
Extracellular Optogenetics to Interrogate Unmodified Primary Cell Functions
No full textInternational audienc
Zuckerberg vs European Union : que peut faire l’UE après les déclarations chocs du patron de Meta ?
No full textL’arrivée de Donald Trump à la tête des États-Unis entraîne un revirement brutal de la politique de modération des grandes plateformes. Ce changement, conforme au droit états-unien, se heurte aux exigences de l’Union européenne en matière de sécurité et de lutte contre la désinformation. Une confrontation juridique et géopolitique se profile entre ces deux approches
Rev@ntiq, Compte-rendu de projet
No full textEn réponse à l'appel à projets 2021-2022 lancé par le dispositif national CollEx-Persée, la Maison de l'Orient et de la Méditerranée (MOM) a soumis une candidature pour le projet Rev@ntiq, visant à améliorer l'accès aux revues scientifiques en archéologie et en sciences de l’Antiquité. Lauréate de cet appel à projets en 2022, la MOM a reçu une bourse du dispositif CollEx-Persée pour mener à bien le projet Rev@ntiq sur deux ans. Ce compte-rendu présente un bilan des objectifs atteints, des ressources mobilisées, des résultats obtenus, ainsi que la méthodologie employée. Il pourra ainsi servir de support pour d’autres projets similaires
Multiple orthoflaviviruses secrete sfRNA in mosquito saliva to promote transmission by inhibiting MDA5-mediated early interferon response
No full textNumerous orthoflaviviruses transmitted through the bites of different mosquito species infect more than 500 million people annually. Bite-initiated skin infection represents a critical and conserved step in transmission and a deeper understanding of this process will promote the design of broad-spectrum interventions to address diverse orthoflavivirus health threats. Here, we identify and characterize a transmission-enhancing viral factor in mosquito saliva that is shared across orthoflaviviruses. Saliva of West Nile virus-infected Culex and Zika virus-infected Aedes contains a viral non-coding RNA, subgenomic orthoflaviviral RNA (sfRNA), within lipid vesicles distinct from virions. Higher concentration of sfRNA in infectious saliva positively correlates with infection intensity in human cells and skin explants. Early sfRNA delivery into transmission-relevant skin cell types and human skin explant demonstrate that sfRNA is responsible for the infection enhancement. Co-inoculation of sfRNA in a mouse model of transmission enhanced skin infection and worsened disease severity, evidencing the role of salivary sfRNA as a transmission-enhancer. Mechanistically, salivary sfRNA attenuates early interferon response in human skin cells and skin explants by altering MDA5-mediated signaling. Our results, derived from two distinct orthoflaviviruses and supported by prior studies, establish salivary sfRNA as a pan-orthoflavivirus transmission-enhancing factor driven by a conserved viral non-coding RNA
Lanternfish as bioindicator of microplastics in the deep sea: A spatiotemporal analysis using museum specimens
No full textInternational audienc
Télépathie, problème des autres esprits, et erreurs de catégorie
No full textVersion française de l'article paru ici : http://doi.org/10.1111/ejop.13045Trad-ejop.13045J'articule dans ce texte quelques considérations autour de ce que l'on appelle la « télépathie » dans le contexte du problème dit « des autres esprits ». J'examine rapidement les conditions d'apparition de cette notion, et les difficultés qu'elle rencontre dès son introduction. Cet examen me permet de distinguer, après avoir montré que la télépathie ne saurait constituer un espoir de solution au problème, deux niveaux de discours : un niveau épistémologique ou ontologique d'une part, et un niveau sémantique ou logique d'autre part. Je mets en avant qu'il y a à ce second niveau des difficultés plus profondes et plus embarrassantes touchant aux « pouvoirs de l'esprit ».Ces difficultés sont très souvent le point aveugle des discussions mobilisant la notion de télépathie (Alan Turing me sert alors d'illustration saillante). Je suggère enfin que cette pseudo-solution (la télépathie) est au fond une réponse à un pseudo-problème (l'inaccessibilité des autres) car les difficultés liées à l'intelligibilité de la télépathie sont parallèles aux difficultés qui grèvent le problème des « autres esprits »
Negative gas adsorption transitions and pressure amplification phenomena in porous frameworks
No full textInternational audienceNanoporous solids offer a wide range of functionality for industrial, environmental, and energy applications. However, only a limited number of porous materials is responsive, i.e. the nanopore size dynamically alters its size and shape as a response to external stimuli such as temperature, pressure, light or the presence of specific molecular stimuli adsorbed inside the voids deforming the framework. Adsorption-induced structural deformation of porous solids can result in unique counterintuitive phenomena. Negative Gas adsorption (NGA) is such a phenomenon which describes the spontaneous release of gas from an “overloaded” nanoporous solid via adsorption-induced structural contraction leading to a total pressure amplification (PA) in a closed system. Such pressure amplifying materials may open new avenues for pneumatic system engineering, robotics, damping, or micromechanical actuators. In this review we illustrate the discovery of NGA in DUT-49, a mesoporous metal-organic framework (MOF), and the subsequent examination of conditions for its observation leading to a rationalization of the phenomenon. We outline the decisive experimental and theoretical methods development required to establish the mechanism of NGA and derive key criteria for observing NGA in other porous solids. We demonstrate the application of these design principles in a series of DUT-49-related model compounds of which several also exhibit NGA. Furthermore, we provide an outlook towards applying NGA as a pressure amplification material and discuss possibilities to discover novel NGA materials and other counterintuitive adsorption phenomena in porous solids in future