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Ineffective Right and Undone Science: the case of the access to administrative algorithms in France
No full textInternational audienceSpecification of administrative algorithms, and tools for making them accountable to the public, represent both an undone science and an ineffective right. We aim at developping knowledge in this twin field -both in computer science, by studying the possible definitions, and in law science, by studying the extent to which such an accountability exists-by the way of the methodology of strategic litigation
An elementary approach to the pressureless Euler-Navier-Stokes system
No full textThe pressureless Euler-Navier-Stokes system can be obtained formally from the Vlasov-Navier-Stokes system, under the assumption that the distribution function describing the density of particles is monokinetic. Its study has been the subject of several recent papers, which have established the global existence of solutions with high enough regularity, for small initial data. In this work, we demonstrate the global existence of strong solutions in the whole space case, without assuming the initial density to be small and regular: it suffices for it to be bounded and for the total mass to be finite. In passing, we obtain optimal decay estimates for the energy and dissipation functionals. As a corollary, we get a long-time description of the density. All these results are based on an elementary energy method, with no need of sophisticated Fourier analysis tools
Étudier une œuvre littéraire avec le jeu de rôle sur table Babel
No full textNational audienceDans le cadre du projet pédagogique et de recherche en ludopédagogie, nous avons mené une recherche de 24 mois sur l'usage du jeu de rôle sur table Babel (Les XII Singes). Notre objectif était de savoir si la proposition ludique du jeu (voyager dans les livres) permettait aux joueurs-apprenants de découvrir ou d'approfondir une œuvre littéraire. Cette conférence présente les résultats de ce travail de recherche sur la pratique du jeu de rôle sur table Babel pour découvrir ou approfondir une œuvre littéraire. Nous abordons également la méthodologie expérimentale déployée ainsi que le dispositif ludopédagogique final pouvant être dupliqué
Adaptive Dirichlet Process mixture model with unknown concentration parameter and variance: Scaling high dimensional clustering via collapsed variational inference
No full textWe propose a novel method that performs adaptive clustering with DPMM using collapsed VI, while incorporating weakly-informative priors for DP concentration parameter alpha and base distribution G0. We illustrate the importance of G0 covariance structure and prior choice by considering different parameterisations of the data covariance matrix. On high-dimensional Gaussian simulations, our model demonstrates substantially faster convergence than a state-of-the-art MCMC splice sampler. We further evaluate performances on Negative Binomial simulations and conduct sensitivity analyses to assess robustness on realistic data conditions. Application to a publicly available leukemia transcriptomic data set comprising 72 samples and 2,194 gene expression successfully recovers every known sub-type, all while identifying additional gene expression-based sub-clusters with meaningful biological interpretation
Les animateurs parlent mal aux enfants
No full textInternational audience« Ils parlent mal aux élèves ! ». Voilà une parole souvent entendue dans les salles des maîtres des école primaires lorsqu’une enseignante, fatiguée de sa matinée de classe, vient s’installer auprès de ses collègues après avoir traversé le réfectoire ou la cour et qu’elle déplore machinalement l’atmosphère qui y règne. Comment comprendre ce jugement et quels enjeux dissimulés pourraient expliquer son caractère trop commun
Repenser la responsabilité sociétale des marques à l'ère de la souveraineté stratégique : une approche intégrative par l'indicateur STAR
No full textInternational audienceThis article proposes an integrated analytical framework for assessing the territorial performance of brands across four key dimensions: Sovereignty, Ecological Transition, Social Autonomy, and Organizational Resilience (acronym STAR). The STAR indicator aims to objectify concepts that have, until now, been difficult to operationalize, in order to facilitate their integration into corporate strategic management. From an academic perspective, it bridges domains that are often treated separately—strategy, CSR, sustainable development, and territorialization. From a managerial perspective, it serves as a structuring self-assessment tool to guide brands toward more sustainable and sovereign trajectories.Cet article propose une grille intégrée d'analyse de la performance territoriale des marques autour de quatre dimensions clés : Souveraineté, Transition écologique, Autonomie sociale et Résilience organisationnelle (acronyme STAR). L'indicateur STAR vise à objectiver des concepts jusque-là peu opérationnalisés, afin de faciliter leur intégration dans le pilotage stratégique des entreprises. Sur le plan académique, il articule des champs souvent disjointsstratégie, RSE, développement durable et territorialisation. Sur le plan managérial, il constitue un outil d'autoévaluation structurant pour engager les marques dans des trajectoires plus durables et souveraines
Convergence of a Control Volume Finite Element scheme for a cross-diffusion system modeling ion transport
No full textAn approximation of a system coupling the cross-diffusion of chemical species within a solvent, subjected to an electric field, is obtained through a control volume finite element (CVFE) scheme on general simplicial meshes in two or three space dimensions. The discrete unknowns of the numerical scheme are derived from the chemical potential of the species. The scheme is designed in order to fulfill entropy inequalities, yielding compactness properties for the discrete solutions and convergence to a weak solution of the continuous problem. Numerical illustrations of the convergence properties are provided in situations where diffusion of ionic species degenerates
Long-term outcomes and temporal trends following liver transplantation for chronic liver disease in intensive care unit.
No full textInternational audienceBackground and Aims: Liver transplantation (LT) remains the definitive treatment for patients with end-stage chronic liver disease (CLD). However, those transplanted while in intensive care unit (ICU) represent a high-risk population. Large-scale data on long-term prognosis in this group are limited. We aimed to assess long-term outcomes in CLD patients undergoing LT from the ICU and to compare outcomes over time.Methods: This retrospective cohort study used the French national transplant registry (CRISTAL). Adults with CLD who underwent LT from the ICU between 2008 and 2018 were included. Organ failures were defined according to EASL CLIF-OF criteria. Five-year survival and associated risk factors were analyzed and compared across four time periods (2008–2010, 2011–2013, 2014–2016, 2017–2018).Results: Among 13,372 LTs performed in France during the study period, 9,686 were for CLD, of whom 1,287 (13.2%) were in the ICU at the time of LT. Alcohol-related liver disease (50%) and viral hepatitis (16.1%) were the leading etiologies. Five-year survival was significantly lower in CLD-ICU patients compared to non-ICU patients (69.2% vs. 79.1%, p<0.0001). Among 1-year survivors, 5-year survival exceeded 83% and was not different to that of CLD patients transplanted outside ICU. Survival by era showed no significant improvement (p=0.28). Age (HR 1.03, p<0.0001), mechanical ventilation (HR 1.57, p=0.0001) and French Donor Risk Score (HR 1.05, 95%CI [1.02-1.09], p<0.001) were independent predictors of mortality.ConclusionPatients transplanted from the ICU have significantly lower long-term survival, primarily due to elevated early post-transplant mortality, with no observed improvement over time. Careful candidate evaluation and donor selection remain critical to improving outcomes in this high-risk population.Impact and Implications: This large national cohort study provides a comprehensive evaluation of long-term outcomes in critically ill cirrhotic patients undergoing liver transplantation while in the ICU. Despite advances in transplant care over the past decade, we observed a persistent survival gap in this high-risk population, primarily driven by increased mortality within the first year after transplantation. Age, the need for mechanical ventilation, and donor-related factors were independently associated with this excess risk. We also found no significant improvement in outcomes over time. These results underscore the continued need for refined candidate selection and donor allocation strategies, taking into account age, pre-transplant clinical stability, and graft quality to optimize post-transplant survival.Trial Registration: ClinicalTrials.gov number NCT0663640
