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Usefulness of 18F-FDG PET-CT in detecting subclinical arteritis and cancer associated with polymyalgia rheumatica
No full textInternational audienceTo assess the prevalence of giant cell arteritis (GCA) or cancer detected via 18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) in patients with polymyalgia rheumatica (PMR) without clinical signs suggestive of GCA
The Online Data Filter for the KM3NeT Neutrino Telescopes
No full textInternational audienceThe KM3NeT research infrastructure comprises two neutrino telescopes located in the deep waters of the Mediterranean Sea, namely ORCA and ARCA. KM3NeT/ORCA is designed for the measurement of neutrino properties and KM3NeT/ARCA for the detection of high\nobreakdashes-energy neutrinos from the cosmos. Neutrinos are indirectly detected using three\nobreakdashes-dimensional arrays of photo\nobreakdashes-sensors which detect the Cherenkov light that is produced when relativistic charged particles emerge from a neutrino interaction. The analogue pulses from the photo\nobreakdashes-sensors are digitised offshore and all digital data are sent to a station on shore where they are processed in real time using a farm of commodity servers and custom software. In this paper, the design and performance of the software that is used to filter the data are presented. The performance of the data filter is evaluated in terms of its purity, capacity and efficiency. The purity is measured by a comparison of the event rate caused by muons produced by cosmic ray interactions in the Earth's atmosphere with the event rate caused by the background from decays of radioactive elements in the sea water and bioluminescence. The capacity is measured by the minimal number of servers that is needed to sustain the rate of incoming data. The efficiency is measured by the effective volumes of the sensor arrays
An “orthorexic society”: The role of psychological flexibility in responding to healthy eating pressures
No full textInternational audienceIn some countries, public health policies and social networks are contributing to making people more responsible for their own health by promoting healthy eating. This context of "healthism" has witnessed the development of orthorexia nervosa. Described as an eating disorder based on an obsession with healthy eating, orthorexia nervosa is not yet included in diagnostic manuals. A central issue in the study of orthorexia is how it differentiates from other eating disorders and how to identify it among the growing number of healthy diets. Flexibility seems to be relevant for distinguishing between the adaptive and pathological forms of adherence to eating habits perceived as healthy. In this respect, psychotherapeutic interventions linked to flexibility are a promising path to support people with orthorexic symptoms, regardless of disorder categorization. Flexibility could also be integrated into the way dietary recommendations are devised, in order to promote the overall physical, psychological and social health
Spatial Distribution of European Grayling Reflects Longitudinal Temperature Patterns in a Swiss River
No full textInternational audienceMost salmonid populations are declining across their entire habitat range, partly because of large‐scale loss of crucial physical habitats. Alterations in river flow and temperature resulting from climate change are likely to further degrade habitat quality, particularly summer thermal conditions experienced by temperature‐sensitive fish species. Understanding how summer thermal conditions control the spatial distribution of ectotherms is thus central to helping project the consequences of climate change and develop management solutions. This study uses snorkelling fish surveys collected over 10 years and airborne thermal infrared (TIR) mapping of surface temperature acquired in 2022 to assess the relationship between European grayling distribution and thermal habitats along a 9‐km long reach of the Allondon River, Switzerland. Results show that all 3 grayling life stages (adults, sub‐adults and juveniles) respond negatively to elevated summer temperature, with distribution patterns highlighting thermal structuring effects on fish populations. The presence of two cooler reaches appears critical to the survival of the Allondon's declining grayling population, while the warmest reach that separates these habitats potentially acts as a thermal barrier during critical summer conditions. These results were used to guide local stakeholders towards short‐term and longer‐term actions to be taken on the river, which include: concerted trans‐national management to protect key upstream tributaries, tree planting to limit summer peak temperature and strategic protection of cold‐water patches that may act as thermal refuges during critical periods
DIA entachée d'une « erreur substantielle ». Conséquences sur le délai d'exercice du droit de préemption urbain
No full textInternational audienceConseil d'État, 7 novembre 2025, no 500233, Société Financière Stratégie et Développement, Lebon T. ; AJDA 2025. 206
Bounded Sort Polymorphism with Elimination Constraints
No full textInternational audienceProof assistants based on dependent type theory-such as Agda, Lean, and Rocq-employ different universes to classify types, typically combining a predicative tower for computationally relevant types with a possibly impredicative universe for proof-irrelevant propositions. Several other universes with specific logical and computational principles have been explored in the literature. In general, a universe is characterized by its sort (e.g., Type, Prop, or SProp) and, in the predicative case, by its level. To improve modularity and better avoid code duplication, sort polymorphism has recently been introduced and integrated in the Rocq prover.However, we observe that, due to its unbounded formulation, sort polymorphism is currently insufficiently expressive to abstract over valid definitions with a single polymorphic schema. Indeed, to ensure soundness of a multi-sorted type theory, the interaction between different sorts must be carefully controlled, as exemplified by the forbidden elimination of irrelevant terms to produce relevant ones. As a result, generic functions that eliminate values of inductive types from one sort to another cannot be made polymorphic; dually, polymorphic records that encapsulate attributes of different sorts cannot be defined. This lack of expressiveness also breaks the possibility to infer principal types, which is highly desirable for both metatheoretical and practical reasons. To address these issues, we extend sort polymorphism with bounds that reflect the required elimination constraints on sort variables. We present the metatheory of bounded sort polymorphism, paying particular attention to the consistency of the resulting constraint graph. We implement bounded sort polymorphism in Rocq and illustrate its benefits through concrete examples. Bounded sort polymorphism with elimination constraints is a natural and general solution that effectively addresses current limitations and fosters the development of, and practical experimentation with, multi-sorted type theories.</p
GATE 10 Monte Carlo particle transport simulation: I. Development and new features
No full textInternational audienceWe present GATE version 10, a major evolution of the open-source Monte Carlo simulation application for medical physics, built on Geant4. This release marks a transformative evolution, featuring a modern Python-based user interface, enhanced multithreading and multiprocessing capabilities, the ability to be embedded as a library within other software, and a streamlined framework for collaborative development. In this Part 1 paper, we outline GATE’s position among other Monte Carlo codes, the core principles driving this evolution, and the robust development cycle employed. We also detail the new features and improvements. Part 2 will focus on the architectural innovations and technical challenges. By combining an open, collaborative framework with cutting-edge features, such a Monte Carlo platform supports a wide range of academic and industrial research, solidifying its role as a critical tool for innovation in medical physics
Organizational learning for exploring Generative AI: CORE-sandbox experiments
No full textInternational audienceGenerative AI (GenAI) holds potential for organizations, offering transformative opportunities while simultaneously raising concerns about its associated risks. Like many emerging technologies, GenAI presents organizations with a significant challenge: navigating uncertainty before making large-scale decisions about which systems to adopt and how to implement and leverage them. Managers cannot rely solely on general knowledge of GenAI; they require insights tailored to their specific organizational context. Drawing on an 18-month study of sandbox experiments conducted within a large international service organization, this paper presents CORE-sandbox experiments as a structured framework for systematically learning about the critical dimensions of uncertainty surrounding GenAI. The framework organizes learning into four key domains: Capabilities, Opportunities, Risks, and Ecosystem. The paper also advances the discourse on organizational learning and dynamic capabilities by demonstrating how in-situ and ex-situ learning cycles reinforce one another and how second and third-order organizational learning emerge under conditions of high uncertainty before GenAI rollout decisions are made
Les artisans sur la colline. Les céramiques achromes et les pithoi à Incoronata : échanges de techniques et de fonctions.
No full textInternational audienc
Verres aluminoborosilicatés dopés au bismuth synthétisés sous haute pression : rôle du bismuth sur la solubilité de l'iode
No full textInternational audienceBismuth-aluminoborosilicate glasses have gained interest as a possible matrix for nuclear waste immobilisation, as bismuth-based sorbents have enhanced affinity for volatile radioisotopes removal. Conjointly, it has been recently demonstrated that using high-pressure conditions is an interesting tool to improve volatile elements retention during glass synthesis. This study tries to combine these two fields showing significant improvement in 129-iodine incorporation into the structure of Bi-bearing glasses synthesised under high-pressure conditions (1 GPa and 1250°C) by comparison with Bi-free glasses or Bi-containing glasses obtained at ambient pressure. Two series of glasses have been investigated in the SiO2-Al2O3-B2O3-Na2O-CaO-Bi2O3 system, either with high (~13 mol.% Al2O3) or low (~5mol.% Al2O3) Al2O3 and Bi2O3 content ranging from 0.5 to 16 mol.%. We show that I incorporation increases with increasing Bi2O3 and can reach up to 2.8 mol.%, which is much higher than Bi-free comparable glasses synthesised under the same conditions. The 11 B NMR analysis demonstrated a drastic decrease in the proportion of tetrahedral BO4 with increasing Bi2O3 content regardless of the alumina content. 27 Al displayed a large majority of IV Al, with a steady increase of CN Al for the Al-rich series, and nearly constant CN Al for the Al-poor series as we increase Bi2O3 content. O 1s XPS spectra demonstrates a clear change towards a general depolymerisation of the glass structure with increasing Bi2O3 content. It confirms the network-modifier role of Bi 3+ in such a glass system and explains the increase in I content. This work paves the way for new glass composition to be synthesised using high-pressure to address the worldwide issue of the volatile nuclear wastes.Les verres à base aluminoborosilicatés dopés en bismuth ont suscité un intérêt croissant en tant que matrice potentielle pour l'immobilisation des déchets nucléaires, notamment car les sorbants à base de bismuth présentent une affinité accrue pour l'adsorption des radio-isotopes volatils. Parallèlement, il a récemment été démontré que l'utilisation de conditions de haute pression constituait un outil intéressant pour améliorer la rétention des éléments volatils lors de la synthèse du verre. Cette étude tente de combiner ces deux domaines en montrant une amélioration significative de l'incorporation de l'iode dans la structure des verres contenant du Bi; synthétisés dans des conditions de haute pression (1 GPa et 1250 °C) par rapport aux verres sans Bi ou aux verres contenant du Bi obtenus à pression ambiante. Deux séries de verres ont été étudiées dans un système a base silicaté, avec une teneur élevée (~13 mol.% Al2O3) ou faible (~5mol.% Al2O3) en Al2O3 et une teneur en Bi2O3 comprise entre 0,5 et 16 mol.%. Nous montrons que l'incorporation d'I augmente avec l'augmentation de Bi2O3 et peut atteindre jusqu'à 2,8 mol.%, ce qui est beaucoup plus élevé que les verres comparables sans Bi synthétisés dans les mêmes conditions. L'analyse RMN 11B a démontré une diminution drastique de la proportion de BO4 tétraédrique avec l'augmentation de la teneur en Bi2O3, quelle que soit la teneur en alumine. Le 27Al a montré une grande majorité d'Al IV, avec une augmentation régulière de CN Al pour la série riche en Al, et un CN Al presque constant pour la série pauvre en Al à mesure que nous augmentons la teneur en Bi2O3. Les spectres XPS O 1s montrent un changement clair vers une dépolymérisation générale de la structure du verre avec l'augmentation de la teneur en Bi2O3 . Cela confirme le rôle de modificateur de réseau du Bi 3+ dans un tel système de verre et explique l'augmentation de la teneur en I. Ces travaux ouvrent la voie à la synthèse d'une nouvelle composition de verre à haute pression pour répondre au problème mondial des déchets nucléaires volatils