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Faire lien, faire lieu : ethnographie des subjectivités féministes à Chengdu, Chine
No full textThis thesis presents an ethnography of feminist spaces in Chengdu, a city in Southwest China. Through fieldwork with women involved in the management of activist spaces, it explores how feminist engagement reshapes relationships with others, individual life paths, and ways of inhabiting space. The aim is to understand how some women redefine their relationships (with themselves and with others) and invest in certain places to experiment with new modes of existence and resistance. These feminist spaces emerge as sites of identity formation and political mobilization in a Chinese context where minority expressions are closely under surveillance.Ce mémoire propose une ethnographie des espaces féministes de Chengdu, ville du Sud-Ouest de la Chine. À travers une enquête auprès de femmes engagées dans la gestion de lieux militants, ce travail explore la manière dont les engagements féministes transforment les rapports à autrui, les trajectoires individuelles et les manières de s’approprier l’espace. Il s'agit de comprendre comment certaines femmes redéfinissent leurs relations (à elle et aux autres) et investissent des lieux pour expérimenter de nouveaux modes d’existence et de résistance. Ces espaces féministes apparaissent comme des moyens de définition identitaire et de mobilisation politique, dans un environnement chinois où les expressions minoritaires sont surveillées
Mechanical behaviour of porous alumina under quasi-static and dynamic loading
No full textInternational audienceThe sensitivity of porous ceramics' mechanical behavior to strain rate is often attributed, in micromechanical models, to a competition between the loading rate and the crack propagation speed initiated at microstructural defects. However, direct experimental evidence for this phenomenon remains limited. In this study, this competition was investigated by conducting compression and tensile tests across a range of strain rates using Split Hopkinson Pressure Bar set-up on alumina ceramics with precisely controlled microstructures. Porosity was introduced into the alumina matrix with well-defined pore size, morphology, and volume fraction.Three porosity levels (1%, 20%, and 60%) and two pore types (microscopic tortuous and mesoscopic isolated spherical) were used to assess the influence of microstructure on mechanical response under dynamic loading.Results indicate that strain rate sensitivity increases with porosity. However, due to the wide dispersion of results, it is challenging to conclude precisely on the specific effect of pore size. The size of the fragments was then used an indicator of the fragmentation mechanisms occurring during sample fracture. The increase in strain rate leads to an overall reduction in fragment size, reflecting the competition between strain rate and crack propagation velocity introduced by micromechanical models. </p
Entretiens pharmaceutiques auprès de patients diabétiques de type 2, hors insulinothérapies
No full textType 2 diabetes is one of the most at risk for cardiovascular complications in metabolic diseases. The French population is particularly at risk of diabetes due to its life expectancy lengthening, sedentary settling, and overweight banalized. For some, it is the disease of the century. However, it could be avoided with early detection, or following basic dietary hygiene rules (RHD). The quality of life as well as associated comorbidities would greatly be reduced by discussion with patients diagnosed about their daily lives and on the impact of this disease. This project of creating a pharmaceutical interview for diabetic patients was born to help patients improve their daily lives. The questionnaire for this interview addresses patients' knowledge about their disease, their medications and treatment patterns and dietary and sedentary lifestyle.Le diabète, notamment celui de type 2, compte parmi les maladies métaboliques les plus à risques de complications cardio-vasculaires. La population française, voyant son espérance de vie s'allonger, la sédentarité s'installer, et le surpoids banalisé, est une cible de choix pour cette pathologie. Pour certains, il s'agit de la maladie du siècle. Pourtant, dépistée à temps, ou en suivant des règles hygiéno-diététiques (RHD) de bases, elle pourrait être évitée. Échanger avec les patients diagnostiqués sur leur quotidien et leur partager des informations permettraient de diminuer fortement l'impact de cette maladie sur leur qualité de vie ainsi que sur les comorbidités associées. C'est ainsi qu'est né le projet d'entretiens pharmaceutiques à destination de patients diabétiques, afin de les aider au mieux dans leur quotidien. Le questionnaire relatif à cet entretien aborde les connaissances des patients sur leur pathologies, leurs médicaments ainsi que leur moment de prise ; et s'intéresse à leur vie quotidienne en évoquant l'alimentation et la sédentarité
Synthesis of new functional mixed anion fluorides by high pressure synthesis
No full textInternational audienc
Super-efficient estimation of future conditional hazards based on time-homogeneous high-quality marker information
No full textInternational audienceWe introduce a new concept for forecasting future events based on marker information. The model is developed in the nonparametric counting process setting under the assumptions that the marker is of so-called high quality and with a time-homogeneous conditional distribution. Despite the model having nonparametric parts, it is established herein that it attains a parametric rate of uniform consistency and uniform asymptotic normality. In usual nonparametric scenarios, reaching such a fast convergence rate is not possible, so one can say that the proposed approach is super-efficient. These theoretical results are employed in the construction of simultaneous confidence bands directly for the hazard rate. Extensive simulation studies validate and compare the proposed methodology with the joint modelling approach and illustrate its robustness for mild violations of the assumptions. Its use in practice is illustrated in the computation of individual dynamic predictions in the context of primary biliary cirrhosis of the liver. © 2025 Biometrika Trust
Pulsar+escape: the recipe for LHAASO sources ?
No full textInternational audienceObservations of our Galaxy at very-high and ultra-high photon energies have revealed a rich population of sources, many of which have significant angular extension and/or are positionally coincident with energetic pulsars. We assessed whether the properties of these gamma-ray emitters are consistent with the predictions of a model for the non-thermal leptonic emission of a pulsar wind nebula expanding within a supernova remnant, including the possibility of particle escape across the different components of the system up to the ambient medium. We used a multi-zone model framework that describes the transport and radiation of a population of ultra-relativistic electron-positron pairs. The dynamics of the system is retrieved from numerical hydrodynamics simulations, which allows to follow the evolution through advanced stages. Model predictions for typical parameter setups are compared to source catalogs issued by the H.E.S.S. and LHAASO collaborations. If particles remain confined in the nebula, 1-100TeV emission is only partially consistent with the properties of observed sources in terms of surface brightness, angular extent, and photon index. In particular, the systems spend a long time in a bright and soft state that has no equivalent in observations. Conversely, including the possibility of energy-dependent particle escape across the object results in a much better agreement, both in the 1-10TeV range explored with H.E.S.S. or LHAASO-WCDA, and in the 20-100TeV range explored by LHAASO-KM2A. Emission components with intermediate to low brightnesses and large to very large sizes result from particles trapped in the remnant or escaped in the surrounding medium. Particle escape, clearly seen in the form of misaligned jets or halos around middle-aged pulsars, is a very important process in much younger systems with 1-100kyr ages, and shapes their appearance as TeV/PeV sources
Donner aux étudiants les moyens d'expérimenter pratiquement les ondes THz térahertz : Travaux pratiques avec des radars FMCW
No full textInternational audienceThis article introduces an innovative pedagogical approach designed to facilitate hands-on teaching of terahertz (THz) waves using compact FMCW radar systems operating at 122 GHz. Traditionally, practical THz education involves expensive, bulky, and complex equipment, limiting accessibility for many educational institutions. To overcome these barriers, the authors propose a radar setup based on affordable SiliconRadar SiGe modules mounted on a 3D-printed support, complemented by two PTFE lenses for adjustable beam focusing. The compact and portable design allows easy deployment on standard classroom tables without specialized infrastructure.Educational activities revolve around the LabVIEW software platform, enabling students to independently acquire and process radar signals. Practical exercises include time-domain processing, Fast Fourier Transform (FFT), spectral analysis, calibration procedures, precise distance and thickness measurements, and beam characterization using the "knife-edge" method. Highly motivated students further extended their experiments by spontaneously developing a sound generation system linked directly to radar signal feedback.This pedagogical methodology emphasizes kinesthetic and interactive learning, with students physically manipulating radar components to tangibly visualize theoretical concepts associated with millimeter waves. The authors highlight significant improvements in student engagement, autonomy, and intrinsic motivation.Future developments aim to integrate advanced data processing techniques, including artificial intelligence, and establish an open-source collaborative platform for educators and researchers to share educational resources, experimental protocols, and software tools, thus democratizing and enhancing THz wave education.Cet article présente une nouvelle approche pédagogique visant à faciliter l'enseignement pratique des ondes térahertz (THz) en utilisant des radars FMCW compacts opérant à 122 GHz. L'objectif principal est de rendre accessibles, abordables et interactifs les travaux pratiques en THz, traditionnellement coûteux et complexes. Les auteurs introduisent un dispositif radar basé sur des modules SiliconRadar SiGe, montés sur un support imprimé en 3D, associé à deux lentilles en PTFE pour un ajustement flexible du faisceau. Ce dispositif est compatible avec une utilisation sur table sans nécessiter une infrastructure complexe.Les activités pédagogiques sont centrées sur l’utilisation du logiciel LabVIEW, permettant aux étudiants d’acquérir et traiter des signaux radar de manière autonome. Les exercices incluent des traitements temporels, la transformée de Fourier rapide (FFT), l’analyse spectrale, la calibration, la mesure précise des distances et épaisseurs, ainsi que l’utilisation de la méthode "knife-edge" pour déterminer la forme et la taille du faisceau radar. Certains étudiants, poussés par une forte motivation intrinsèque, ont même étendu leurs travaux en développant spontanément un système de génération sonore basé sur les signaux radar.Cette méthodologie pédagogique promeut un apprentissage kinesthésique et interactif, où les étudiants manipulent directement les composants du radar pour visualiser concrètement les concepts théoriques associés aux ondes millimétriques. Les auteurs soulignent les bénéfices importants en termes d'engagement, d'autonomie et de motivation des étudiants.Les développements futurs incluent l’intégration d’outils avancés tels que l’intelligence artificielle pour le traitement des données et la création d’une plateforme collaborative open-source permettant aux enseignants et chercheurs de partager ressources et protocoles pédagogiques liés à l’enseignement des ondes THz
Suppression of long-range weberite-type ordering in high temperature processed Gd<sub>3+x</sub>Nb<sub>1-x</sub>O<sub>7-x</sub> (x = 0 and 0.25) synthesised by co-precipitation and direct crystallization of the melt
No full textInternational audienceThe synthesis of cubic derivatives of rare-earth pyrochlores such as Gd3NbO7 is of interest for the development of new optical ceramics with high transparency (low birefringence) in visible to mid-IR wavelengths and high refractive index. At ambient temperature, Gd3NbO7 adopts an orthorhombic weberite-type structure with long range ordering of Nb and Gd on a fluorite-type sublattice. Here, we explore ways of suppressing this long-range ordering to achieve a cubic phase, by (i) using co-precipitation and direct crystallization of the undercooled melt as nonequilibrium synthesis routes, and (ii) tuning the gadolinium content to disrupt the local cation ordering directly, according to the formula Gd3+xNb1-xO7-x. PXRD analysis confirmed the orthorhombic weberite-type structure of Gd3NbO7 (x = 0) prepared by co-precipitation, but the long-range weberite-type ordering was absent in Gd3.25Nb0.75O6.75 (x = 0.25) even after a high temperature heat-treatment. Strikingly, weberite-type superstructure peaks were absent from both compositions prepared by melt-quenching, with both indexed to cubic defect-fluorite structures. The melt-quenched Gd-rich (x = 0.25) fully-crystallised beads had a transparent appearance. The local environment of the RE3+ ion was probed by spectroscopic characterizations including second harmonic generation measurements which confirmed at the microscale the centric symmetry and the associated disordered RE environment obtained at high temperatures. These results open new pathways to visible and IR-transparent optical ceramics based on Gd3+xNb1-xO7-x
Marshall-Plan Ablation Strategy Versus Pulmonary Vein Isolation in Persistent AF: A Randomized Controlled Trial
No full textInternational audienceBACKGROUND: Beyond pulmonary vein (PV) isolation, the optimal ablation strategy for persistent atrial fibrillation (AF) remains poorly defined. The purpose of this study was to compare 2 ablation strategies in the treatment of patients with persistent AF: a comprehensive ablation strategy based on anatomic considerations versus PV isolation alone. METHODS: The Marshall-Plan trial is a prospective, randomized, parallel-group, controlled clinical trial of superiority conducted at the Bordeaux University Hospital. Consecutive patients with symptomatic, documented persistent AF were included and randomized into 2 arms: Marshall-Plan consisting of PV isolation with additional ablation including vein of Marshall ethanol infusion, and lines of block at the mitral, dome, and cavotricuspid isthmuses versus PV isolation alone. The main outcome was the 1-year freedom from any arrhythmia (atrial fibrillation/atrial tachycardia >30 seconds) after a single ablation procedure with or without any antiarrhythmic medication at 12 months. RESULTS A total of 120 patients were included (age 65 +/- 8 years; 21 women). Two patients were excluded from analysis. All PVs were successfully isolated in both groups. In the Marshall-Plan group, vein of Marshall ethanol infusion was completed in 57 (97%) patients. Conduction block across linear lesions was obtained in 93%, 92%, and 93% of the mitral, dome, and cavotricuspid isthmuses, respectively. The full lesion set was successfully completed in 52 (88%) patients in the Marshall-Plan group and 59 (100%) patients in the PV isolation group. At 12 months, freedom from recurrence of atrial arrhythmia >30 seconds after 1 ablation procedure, with or without antiarrhythmic medication, had occurred in 51 of the 59 (86.4%) patients assigned to the Marshall-Plan approach, and 39 of the 59 (66.1%) patients assigned to PV isolation only (P=0.012). CONCLUSIONS: In this prospective randomized controlled trial, the Marshall-Plan strategy was significantly superior to a PV isolation strategy at 12 months