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Supercritical CO2 Sorption Within Polymers Used in Medical Devices and Their Packaging
No full textInternational audienceThermodynamic and kinetic aspects of CO 2 sorption and the resulting swelling are investigated in several commercial polymer‐based medical devices and packaging materials, using in situ FTIR spectroscopy under mild processing conditions (40°C–50°C and 8–20 MPa). At thermodynamic equilibrium, significant CO 2 uptake (up to 41% w/w) and volume swelling (up to 62%) are observed in silicones and poly(L‐lactide‐co‐ε‐caprolactone) copolymers, whereas limited sorption occurs in polyolefins (polypropylene, high‐density polyethylene) and in polyester films coated with low‐density polyethylene. These differences are attributed to intrinsic polymer properties; sorption and swelling are favored in polymers combining a highly amorphous structure with elevated chain mobility, and the presence of functional groups with chemical affinity for CO 2 . Among the studied materials, glycol‐modified polyethylene terephthalate exhibits a distinct behavior, characterized by initial CO 2 uptake followed by pressure‐induced crystallization after several hours of exposure
On the design and implementation of Modular Explicits
No full textInternational audienceWe present and discuss the design and implementation of modular explicits, an extension of OCaml first-class modules with module-dependent functions, i.e., functions taking first-class modules as arguments. We show some difficulties with the present use of first-class modules and how modular explicits solve them in a simpler, more direct way. Modular explicits are fully compatible with, and can be presented as an extension of first-class modules, which can be precisely formalized by elaboration of OCaml modules and mode-dependent functions into F ω . Interestingly, type inference for modular explicits reuses the mechanism designed to ensure principal types in the presence of semi-explicit first-class polymorphism, already used in OCaml for the typechecking of polymorphic methods and its recent extension with polymorphic parameters. Modular explicits are meant to be the underlying language in which modular implicits, i.e., module arguments left implicit from their signatures, should be elaborated.<
A safari across France: soil fauna insights from a nationwide soil quality monitoring program
No full textInternational audienceSoil biodiversity is fundamental to ecosystem functioning but remains underrepresented in conservation policies and large-scale monitoring. Here, we present RMQS-Biodiversity, a nationwide soil biodiversity survey integrated into the French Soil Quality Monitoring Network (RMQS), and illustrate its potential for soil ecology research. In this pioneer study, we examine three major ecological aspects: (i) how systematic grid-based sampling captures micro-food web patterns using nematode communities, (ii) the spatial turnover of detritivore communities (Collembola, Isopoda, Diplopoda) in response to environmental and geographic gradients, and (iii) the influence of macroecological drivers on predator (Carabidae) morphological traits. Across 69 sites, we identified a few widespread species coexisting with numerous rare taxa, underscoring the value of large-scale surveys for detecting cryptic biodiversity. Nematode indicators revealed high variability in food web structure across land uses, with increased facultative phytophagous nematodes in forests. Isopods and diplopods were strongly structured by dispersal constraints, while springtails exhibited weaker environmental responses, likely due to their higher dispersal capacity. Additionally, sexual size dimorphism in Carabidae varied by habitat, with female-biased dimorphism in closed habitats but no dimorphism in open environments, highlighting habitat stability's role in shaping morphological traits. This study demonstrates the value of multi-taxon, multi-trophic biodiversity assessments in long-term soil monitoring. RMQS-Biodiversity provides a robust framework for soil biodiversity monitoring and conservation, refining bioindicators of soil quality and informing policies such as the EU Soil Monitoring Law
Neuro-oscillatory models of cortical speech processing
No full textInternational audienceIn this review, we examine computational models that explore the role of neural oscillations in speech perception, spanning from early auditory processing to higher cognitive stages. We focus on models that use rhythmic brain activities, such as gamma, theta, and delta oscillations, to encode phonemes, segment speech into syllables and words, and integrate linguistic elements to infer meaning. We analyze the mechanisms underlying these models, their biological plausibility, and their potential applications in processing and understanding speech in real time, a computational feature that is achieved by the human brain but not yet implemented in speech recognition models. Real-time processing enables dynamic adaptation to incoming speech, allowing systems to handle the rapid and continuous flow of auditory information required for effective communication, interactive applications, and accurate speech recognition in a variety of real-world settings. While significant progress has been made in modeling the neural basis of speech perception, challenges remain, particularly in accounting for the complexity of semantic processing and the integration of contextual influences. Moreover, the high computational demands of biologically realistic models pose practical difficulties for their implementation and analysis. Despite these limitations, these models provide valuable insights into the neural mechanisms of speech perception. We conclude by identifying current limitations, proposing future research directions, and suggesting how these models can be further developed to achieve a more comprehensive understanding of speech processing in the human brain
Dire ou ne pas dire son nom en ligne : l'anonymat des journalistes à l'ère numérique
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Palatini Gauss-Bonnet theory
No full textInternational audienceWe consider a class of models in even spacetime dimensions which share many similarities with Chern-Simons theories in odd spacetime dimensions . The independent dynamical variables of these models are a -connection and a metric in internal space. The action is a polynomial of degree in the curvature of the connection, with indices saturated by means of the metric and the Levi-Civita tensor. We show that the theory has no local degree of freedom in spacetime dimensions (), where it can be reformulated as a constrained model, but that its dynamics is more intrincate in higher dimensions (n>1), where local degrees of freedom are present. We treat in detail the cases of and spacetime dimensions
Non-local aspects of cognition
No full textInternational audienceThis article explores the non-local aspects of cognition in two main directions, respectively contradicting the idea that 1) it exclusively refers to the cognitive subject's intrinsic mental aptitudes and that 2) it is exclusively centred on the subject’s spatial and temporal localisation. Following 4E cognition, the first direction mentions quite reasonable externalist and multiscale aspects of cognition by successively referring to Clark’s and Chalmers’ concept of extended mind, to social cognition, to Hutchins’ concept of distributed cognition and to Laurent’s multiscale enaction model. The second direction the concept of non-local cognition will be explored puts into question the spatio-temporal locality of cognition since it refers to the possibility of extra-sensory perception. The reality of extra-sensory perception is suggested by the non-reductive solutions to the problem of consciousness, and it is supported by very significant experimental results. The millenary interest in extra-sensory perception will be mentioned, with a special focus on Hinduism for its explicit reference in Pantanjali’s Yoga Sutra. Some of the significant experimental tests aimed to show its existence and some hints for building a theoretical modelling of it will then be presented. The reasons why the reality of extra-sensory perception is generally rejected by the scientific community despite numerous significant experimental results, as well as philosophical justifications and theoretical advances, will be discussed. This article pays particular attention to the second sense of ‘non-local’, based on the possibility of extra-sensory perception, insofar as this disturbing but rigorous scientific field of research is almost not at all considered by the current studies in cognitive science
Migration Law and Politics in Contemporary France. Under the Eyes of the Far-Right
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Self-interacting approximation to McKean-Vlasov long-time limit: a Markov chain Monte Carlo method
No full textInternational audienceFor a certain class of McKean-Vlasov processes, we introduce proxy processes that substitute the mean-field interaction with self-interaction, employing a weighted occupation measure. Our study encompasses two key achievements. First, we demonstrate the ergodicity of the self-interacting dynamics, under broad conditions, by applying the reflection coupling method. Second, in scenarios where the drifts are negative intrinsic gradients of convex mean-field potential functionals, we use entropy and functional inequalities to demonstrate that the stationary measures of the self-interacting processes approximate the invariant measures of the corresponding McKean-Vlasov processes. As an application, we show how to learn the optimal weights of a two-layer neural network by training a single neuron
Combined dark matter search towards dwarf spheroidal galaxies with Fermi-LAT, HAWC, H.E.S.S., MAGIC, and VERITAS
No full textInternational audienceDwarf spheroidal galaxies (dSphs) are excellent targets for indirect dark matter (DM) searches using gamma-ray telescopes because they are thought to have high DM content and a low astrophysical background. The sensitivity of these searches is improved by combining the observations of dSphs made by different gamma-ray telescopes. We present the results of a combined search by the most sensitive currently operating gamma-ray telescopes, namely: the satellite-borne Fermi-LAT telescope; the ground-based imaging atmospheric Cherenkov telescope arrays H.E.S.S., MAGIC, and VERITAS; and the HAWC water Cherenkov detector. Individual datasets were analyzed using a common statistical approach. Results were subsequently combined via a global joint likelihood analysis. We obtain constraints on the velocity-weighted cross section for DM self-annihilation as a function of the DM particle mass. This five-instrument combination allows the derivation of up to 2-3 times more constraining upper limits on than the individual results over a wide mass range spanning from 5 GeV to 100 TeV. Depending on the DM content modeling, the 95% confidence level observed limits reach 10 cms and 10 cms, respectively, in the annihilation channel for a DM mass of 2 TeV