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Invariance Galoisienne des zéros centraux de fonctions L
No full textWe prove the invariance under the Galois group of the vanishing at 1/2 of standard and Rankin-Selberg L-functions for certain self-dual or conjugate self-dual algebraic cuspidal automorphic representations for general linear groups over an arbitrary number field. The proof uses Goresky-Harder-MacPherson weighted cohomology and the construction of certain discrete automorphic representations for classical groups as residues of Eisenstein series. New difficulties appear concerning certain intertwining operators. These are solved in the appendix by J.-L. Waldspurger and O. Taïbi proving the holomorphy and non-vanishing of these operators. We also prove the Galois invariance of epsilon factors, implying Galois invariance of the parity of the order at 1/2 of L-functions.Nous démontrons l'invariance Galoisienne de la propriété d'annulation en 1/2 des fonctions L standard ou de Rankin pour certaines représentations automorphes cuspidales algébriques régulières autoduales ou autoduales conjuguées de groupes linéaires sur un corps de nombres arbitraire. Il s'agit de l'analogue côté automorphe d'une conjecture de Deligne portant sur les fonctions L de motifs purs sur les corps de nombres. La démonstration repose sur l'utilisation de la cohomologie pondérée de Goresky-Harder-MacPherson et sur la construction de certaines représentations automorphes discrètes pour les groupes classiques comme résidus de séries d'Eisenstein, mais l'abandon de l'hypothèse "F totalement réel" introduit de nouvelles difficultés concernant certains opérateurs d'entrelacement. Celles-ci sont résolues grâce à l'appendice, rédigé par J.-L. Waldspurger et l'un d'entre nous, démontrant l'holomorphie et la non-annulation de certains opérateurs d'entrelacement normalisés. Nous démontrons également l'invariance Galoisienne des constantes des équations fonctionnelles ("root numbers") correspondantes, impliquant l'invariance Galoisienne de la parité de l'ordre d'annulation en 1/2 de ces fonctions
Quelle autonomie promise par les prothèses ? Réflexions à la croisée des disability studies et des STS sur ce qui constitue une prothèse « adaptée ».
No full textInternational audienc
RGE_scrapping
No full textCe repository met à disposition le code pour scrapper le [registre des groupes d'expert de la Commission Européenne](https://ec.europa.eu/transparency/expert-groups-register/screen/expert-groups?lang=en). Il permet de récupérer les informations au format .json afin de pouvoir rendre compte des interactions entre les acteurs du RGE
Investigation of lubricant flow in a planetary bearing cavity under stationary carrier condition
No full textPlanetary bearings are critical components in planetary transmission systems. As transmission systems evolve toward higher speeds, the lubrication of planetary bearings faces significant challenges. In this study, a specialized test rig was developed to visualize the oil flow in a planetary bearing cavity under a stationary carrier condition, a configuration featuring outer ring rotation and central oil supply. The experimental results reveal the oil flow patterns and distribution characteristics within the bearing cavity. Additionally, a dynamic-static fluid domain coupled numerical model was established to simulate the oil-air two-phase flow field in the rotating bearing domain. This model was used to analyze the variations in oil distribution inside the bearing cavity and the oil volume fraction(OVF) on component surfaces under different speeds. The research results indicate that the bearing cavity is fully filled with oil at low speeds. As the speed increases, the oil near the roller end faces on the inner ring side begins to decrease, and an arc-shaped oil film forms along the inner side of the cage. With further speed increase, this oil film expands radially outward. At 9000 r/min, only a small amount of oil remains distributed near the outer ring. Increasing the oil flow rate further enhances the OVF on these surfaces, which can alleviate oil starvation in the lubrication zone between the rollers and the inner ring under highspeed conditions. However, higher flow rates also lead to increased churning losses in the planetary bearing. The research results provide theoretical guidance for the lubrication design of planetary bearings in transmission systems
DataLAC : intelligence artificielle dans un lac de données pour valoriser les archives archéologiques
No full textDémoNational audienceThe DataLAC project focus on the use of artificial intelligence for the alignment, annotation and interpretation of heterogeneous documents enriched with semantic metadata and aggregated within a data lake. This project seeks to digitize, unify and make accessible over thirty years of field notes (1947–1977), scientific publications, and archives related to the Iberian archaeological site of Ullastret. These diverse materials are integrated into an interoperable data lake designed to manage the heterogeneity of sources and to support complex research queries. The DataLAC project thus constitutes a generalizable proof of concept, demonstrating the potential of data lake architectures and AI-driven methodologies for the exploitation and interpretation of archaeological archives.Notre travail dans le cadre du projet DataLAC explore comment l'extraction automatisée de métadonnées depuis des carnets de fouille manuscrits, au sein d'un lac de données intégrant des sources de données hétérogènes, peut transformer l'exploitation d'archives archéologiques. En s'appuyant sur le cas du site ibérique d'Ullastret en Catalogne et ses trente années de documentation de terrain (1947-1977), le projet vise à démontrer l'apport d'un lac de données dont l'architecture comprend quatre phases : (a) numérisation des carnets manuscrits et de la documentation scientifique ; (b) transcription automatique par apprentissage automatique ; (c) extraction et modélisation des métadonnées enrichies sémantiquement ; (d) interrogation sémantique des documents et métadonnées. L'enjeu central réside dans la capacité du lac de données à réunir des sources documentaires dispersées et à en extraire automatiquement des informations structurées permettant de nouvelles formes d'analyse. DataLAC constitue ainsi une preuve de concept sur la manière dont l'intelligence artificielle appliquée à l'extraction de métadonnées peut renouveler les pratiques de recherche en archéologie, en rendant exploitables et interrogeables des corpus jusqu'alors difficiles d'accès
Boundary-layer parameterization for assessing temperature and evaporation in floating photovoltaics at the utility-scale
No full textInternational audienceA precursor model for parameterizing the effects of photovoltaic powerplants on the atmospheric boundary layer is developed using computational fluid dynamics. The method allows one to compute the surface roughness lengths, aerodynamical resistances of covered surfaces and convective heat transfer coefficients, adapted for any photovoltaic module layouts and wind directions. It has been applied for two setups: a wind tunnel system and a utility-scale floating photovoltaic installation. In these cases, the altitude-based velocity profiles was reproduced over the arrays; and we found that the turbulence generated by the photovoltaic/atmosphere interaction is greater for head-and tailwinds than sidewinds, therefore affecting the environment and the photovoltaic system. Constructing a digital twin of the floating array using large-scale meteorological fields and the parameters of the precursor model, the temperature of a monitored module was calculated and a spatial variation of 1.3 °C∕km and 5.8 °C∕km was estimated at the utility scale. Moreover, the waterbody evaporation was reduced by 40%-50% due to the photovoltaic panels blocking the vapour removal processes. This result decreased to 14%-20% when considering the flow spatial variations across the waterbody. Further research is necessary to adapt the parameterization to scenarios with low wind velocity
Mind wandering and its relationship with sustained attention and executive functions in preschoolers
No full textInternational audienceMind wandering (MW) is a phenomenon that has been largely described in adults, during which thoughts do not stay on the current tasks or goals. Considering its negative impact on educational outcomes, measuring and understanding MW in children is essential. MW has been associated with attentional and executive performance in children above 8 years old. Given the huge changes in attention and executive functions organization before 6 years old, our study aimed at exploring how mind wandering interacts with these processes in preschoolers.Sixty children aged 4 to 6 years old were asked to evaluate their mind wandering propensity in the classroom using an adapted daydreaming questionnaire. They were also administered neuropsychological tests and questionnaires evaluating sustained attention, processing speed, cognitive flexibility, inhibition and a selection of individual traits.Preschoolers’ self-evaluation strongly correlated with their teacher’s evaluation, showing the feasibility of assessing MW in young children. The MW scores also correlated with the children’s performance in several tests assessing sustained attention, processing speed, cognitive flexibility and inhibition, as well as some individual traits. A latent variable modeling revealed that MW is best modeled by a latent factor independent from attention, speed and inhibition, but highly correlated with attention.Our results thus reveal the central role of attention in child development, suggesting that mind wandering in preschoolers could be linked to attention immaturity
An overview of the preparation methods and applications of liposomes. A focus on membrane stability
No full textInternational audienc
Alignement d'ontologies frugal pour servients WoT
No full textInternational audienceIn distributed and constrained Web of Things (WoT) infrastructures, servients exchange RDF messages that can rely on compact formats to reduce both bandwidth and memory footprint. To this end, in the context of the CoSWoT project, we adapted the CBOR-LD specification. As servients can connect or appear in these infrastructures, each using a different dialect, there is a need for off-the-shelf interoperability during message exchanges at runtime. This paper presents a frugal workflow to detect semantic similarity among messages encoded in CBOR-LD using heterogeneous vocabularies. We experimented different ML-based approaches: a lightweight neural network, a decision tree-based model and a transformer-based architecture. We present a end-to-end pipeline able to integrate each of these algorithms and provide alignment predictions. We ran our experiments on a catalogue of more than 700 production payloads curated to train the models. Our results show various levels of prediction accuracy regarding approaches and model sizes, leading to appropriate choices depending on available resources on targeted platforms.Dans une infrastructure Web des Objets (WoT) distribuée et contrainte, des servients échangent des messages RDF pouvant s’appuyer sur des formats compacts afin de réduire à la fois la bande passante et l’empreinte mémoire. À cette fin, dans le cadre du projet CoSWoT, nous avons adapté la spécification CBOR-LD. Comme les servients peuvent se connecter ou apparaître au sein de ces infrastructures, chacun utilisant un dialecte différent, il est nécessaire d’assurer à l'exécution et de manière automatique une interopérabilité entre les servients à partir des messages qu'ils échangent. Cet article présente une méthodologie permettant de détecter de manière frugale la similarité sémantique entre des messages encodés en CBOR-LD utilisant des vocabulaires hétérogènes. Nous avons expérimenté différentes approches basée sur l’apprentissage automatique : un réseau de neurones léger, un modèle basé sur des arbres de décision et une architecture transformeur. Nous présentons un pipeline capable d’intégrer chacun de ces algorithmes et de fournir des prédictions d’alignement. Nous avons mené nos expériences sur un catalogue de plus de 700 messages produits par des servients, sélectionnés pour entraîner les modèles. Nos résultats montrent divers niveaux de précision des prédictions selon les approches et la taille des modèles, permettant de choisir une approche en fonction des ressources disponibles sur les plateformes visées
Catheter Ablation of Ventricular Arrhythmias in Patients With Congenital Heart Diseases
No full textInternational audienceBackground: Sudden death and ventricular arrhythmias (VAs) remain a significant concern among patients with congenital heart disease (CHD). Although catheter ablation techniques have improved dramatically over the last decade, current evidence in this specific population is primarily derived from small retrospectvie studies.Objectives: The aim of this study was to describe the burden and characteristics of VAs targeted by catheter ablation in CHDs, as well as associated outcomes and emerging preventive ablative strategies.Methods: This prospective nationwide study included all patients with CHD referred for catheter ablation of a VA from 2020 to 2024 in France. The primary outcome was the rate of per-procedural acute success. Secondary outcomes included complications as well as freedom from arrhythmia recurrence.Results: Among a total of 1,192 consecutive catheter ablation procedures, 210 (17.6%) VA catheter ablations were performed in 190 patients (mean age 43.8 ± 15.5 years; 63.8% male): ventricular tachycardia (VT) was targeted in 164 (78.1%) procedures and premature ventricular complex in 53 (25.2%) (both VT and premature ventricular complex were targeted in 7). Fourteen (6.7%) patients had a simple CHD, 161 (76.7%) a moderate CHD, and 35 (16.7%) a complex CHD. In patients with tetralogy of Fallot (n = 126), catheter ablation was performed without clinically documented VA in 46 (36.5%), mainly before transcatheter or surgical intervention. Overall, the clinical arrhythmia was successfully ablated in 182 (86.7%) patients. An acute complication was reported in 6 (2.9%) procedures, with no related death. The overall 1- and 2-year rates of freedom from recurrence were 81.5% (95% CI: 75.3%-88.4%) and 78.2% (95% CI: 71.2%-85.8%), respectively. The presence of anatomical isthmuses related to prior cardiac surgeries was associated with lower recurrence rates (HR: 0.30; 95% CI: 0.14-0.64; P < 0.001).Conclusions: VAs represent approximately 20% of catheter ablation procedures performed in patients with CHD. This large cohort provides key insights into the effectiveness of catheter ablation and the main mechanisms of VAs in patients with CHD. The significant differences in outcomes reported depending on underlying substrate are important to consider to inform the benefit/risk assessment