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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
Promesses et limites des big data pour l’étude des pratiques sportives : le cas des applications de course à pied
No full textInternational audienceFor the past decade, editors of running apps have been exploiting the activity data generated by these digital devices, enriching it with questionnaires and publishing surveys on their users' practices. Based on enormous amounts of diverse data, the ambition is legitimate at first glance. However, several questions arise regarding the authority that tends to emanate from massive amounts of information, the volume of which does not guarantee its relevance. Combining documentary analysis and interviews, we examined the methodological validity of these studies, as well as the subsidiary contribution of this big data in relation to socio-demographic surveys on sports practices. This empirical work highlights significant weaknesses in terms of rigor and representativeness, as well as limited revelatory effects in relation to pre-existing knowledge. This does little to alter the belief in the informative potential of big data, which is considered meaningful by virtue of its massive scale. They allow for an overinterpretation marked by performativity, revealing the informational and communicational facet of data, which becomes a medium for narrative processes emphasizing rupture and novelty. Positioning oneself as a resource, or even a reference in terms of studies, statistics, and market data on running and its (r)evolutions takes precedence over the reliability of analyses and interpretive caution. Therefore, having access to large amounts of data, emphasizing its robustness, and then backing it up with descriptions that amplify real developments leads to taking on the elegant role of a pioneering descriptor of major trends of change.Résumé Depuis une dizaine d’années, des créateurs d’applications de course à pied exploitent les données d’activité générées par ces dispositifs numériques, les enrichissent de questionnaires et publient des enquêtes sur les pratiques de leurs utilisateurs. S’appuyant sur d’énormes quantités de données plurielles, l’ambition semble de prime abord légitime. Plusieurs questions se posent néanmoins quant au caractère d’autorité qui tend à émaner d’informations massives dont le volume ne garantit pas la pertinence. En combinant analyse documentaire et entretiens, nous nous sommes penchés sur la validité méthodologique de ces études, ainsi que sur l’apport subsidiaire de ces big data par rapport aux enquêtes socio-démographiques sur les pratiques sportives. Ce travail empirique met en évidence d’importantes fragilités en termes de rigueur et de représentativité, ainsi que des effets de révélation limités au regard des connaissances préexistantes. Cela n’altère guère la croyance dans le potentiel informatif des big data , considérées comme parlantes en vertu de leur dimension massive. Elles permettent une surinterprétation empreinte de performativité, révélant la facette info-communicationnelle de data devenant support de processus narratifs soulignant la rupture et la nouveauté. Se positionner comme une ressource, voire une référence en termes d’études, de statistiques et de données de marché sur la course à pied et ses (r)évolutions prend le dessus sur la fiabilité des analyses et la prudence interprétative. Dès lors, disposer de chiffres volumineux, asséner leur robustesse, puis y adosser des descriptions amplifiant les évolutions réelles conduisent à endosser l’élégant costume de descripteur pionnier de tendances lourdes de changement
Search for planetary-mass ultra-compact binaries using data from the first part of the LIGO--Virgo--KAGRA fourth observing run
No full textInternational audienceWe present a search for gravitational waves from inspiraling, planetary-mass ultra-compact binaries using data from the first part of the fourth observing run of LIGO, Virgo and KAGRA. Finding no evidence of such systems, we determine the maximum distance reach for such objects and their merger rate densities, independently of how they could have formed. Then, we identify classes of primordial black-hole mass distributions for which these rate limits can be translated into relevant constraints on the mass distribution of primordial black holes, assuming that they compose all of dark matter, in the mass range . Our constraints are consistent with existing microlensing results in the planetary-mass range, and provide a complementary probe to sub-solar mass objects
Reversible Strong Metal‐Support Interactions in Co/TiO 2 Catalysts Driven by CO 2
No full textInternational audienceStrong metal–support interactions can significantly influence catalytic performance. On titania supports, these interactions often involve the formation of a substoichiometric TiO X overlayer during high‐temperature reduction, which can be reversed by treatments under dioxygen. Under CO 2 hydrogenation conditions, where water is produced, complete removal of the TiO X overlayer has been reported, raising questions about its stability in the presence of a mild oxidant such as CO 2 . In this study, in situ and operando techniques were employed to examine the effect of varying conditions on both the titania overlayer and cobalt species in a Co/TiO 2 catalyst. After reduction at 350 °C, the overlayer consisted of stoichiometric anatase TiO 2 , while cobalt remained partially reduced. Exposure to CO 2 /H 2 at 220 °C enabled complete cobalt reduction without affecting the TiO 2 overlayer. In contrast, pure CO 2 at 220 °C caused overlayer removal and full cobalt oxidation. The impact of this CO 2 ‐mediated reversibility on CO 2 hydrogenation was also evaluated. Although steady‐state activity was largely unaffected, the transient regime showed substantial changes in selectivity and behavior. These results demonstrate that different treatments can strongly influence both the stability and reactivity of Co/TiO 2 catalysts, highlighting the importance of dynamic SMSI effects in CO 2 hydrogenation
Types listes pour les langages conscient des ressources : une approche implicite
No full textA novel formalisation of variable control in languages with implicit names based on de Bruijn indices is presented.We design and implement three languages: first, a restricted language with implicit names; then, a restricted calculus with implicit names and explicit substitution, and finally, an extended calculus with implicit names, implicit substitution and resource control. We propose a novel concept of list types, which are used to give a simple and manageable definition of linearity. We develop an implementation in Haskell
From Show Programmes to Data: Designing a Workflow to Make Performing Arts Ephemera Accessible Through Language Models
No full textMany heritage institutions hold extensive collections of theatre programmes, which remain largely underused due to their complex layouts and lack of structured metadata. In this paper, we present a workflow for transforming such documents into structured data using a combination of multimodal large language models (LLMs), an ontology-based reasoning model, and a custom extension of the Linked Art framework. We show how vision-language models can accurately parse and transcribe born-digital and digitised programmes, achieving over 98% of correct extraction. To overcome the challenges of semantic annotation, we train a reasoning model (POntAvignon) using reinforcement learning with both formal and semantic rewards. This approach enables automated RDF triple generation and supports alignment with existing knowledge graphs. Through a case study based on the Festival d'Avignon corpus, we demonstrate the potential for large-scale, ontology-driven analysis of performing arts data. Our results open new possibilities for interoperable, explainable, and sustainable computational theatre historiography
Are There Differences in Ankle Mechanics After Total Ankle Arthroplasty in Patients Suffering From Post-fracture vs Post-sprain End-Stage Ankle Osteoarthritis?
No full textInternational audienceBackground: To our knowledge, no study is available comparing the change in ankle mechanics during gait after total ankle arthroplasty (TAA) based on the origin of the osteoarthritis. As the nature of trauma is different in patients sustaining post-fracture ankle osteoarthritis (PFOA) from those sustaining post-sprain ankle osteoarthritis (PSOA), it could be expected that the outcomes of TAA, in terms of ankle mechanics during gait, would be different in the 2 groups. A prospective matched comparative study was therefore performed to investigate whether patients sustaining PFOA had different outcomes in terms of changes to ankle mechanics during gait (before surgery vs 1 year after surgery), compared with patients sustaining PSOA. Methods: Fifteen patients with PFOA and 15 patients with PSOA scheduled for primary TAA for pain relief were recruited and peer-matched based on their demographic and spatiotemporal data. All patients underwent a 3D gait analysis before and after surgery, during which a kinematic and kinetic multi-segment foot model was used to quantify inter-segmental joint kinematics and kinetics. Results: The PFOA group exhibited significantly lesser pre- vs postoperative increases in ankle (Shank-Calcaneus) joint peak power, and ankle (Shank-Calcaneus) joint work after TAA compared with the PSOA group. Furthermore, the results demonstrated a trend toward greater increases in peak ankle (Shank-Calcaneus) joint plantarflexion moment and in negative ankle (Shank-Calcaneus) joint work for the PSOA group compared with the PFOA group. Conclusion: This study suggests that patients sustaining PFOA have smaller pre- to postoperative gains in ankle (Shank-Calcaneus) joint power and ankle (Shank-Calcaneus) joint work during gait after TAA compared with patients sustaining PSOA, with modest between-group effects. Although evidence in TAA is lacking, insights from knee replacement suggest prehabilitation and nutritional support may mitigate deficits, representing a potentially essential strategy for PFOA patients requiring further validation
Renaming in distributed certification
No full textInternational audienceLocal certification is the area of distributed network computing asking the following question: How to certify to the nodes of a network that a global property holds, if they are limited to a local verification? In this area, it is often essential to have identifiers, that is, unique integers assigned to the nodes. In this short paper, we show how to reduce the range of the identifiers, in three different settings. More precisely, we show how to rename identifiers in the classical local certification setting, when we can (resp. cannot) choose the new identifiers, and we show how a global certificate can help to encode very compactly a new identifier assignment that is not injective in general, but still useful. We conclude with a number of applications of these three results
Measurement of the p correlation function in pp collisions at TeV
No full textInternational audienceIn this letter, the first measurement of the femtoscopic correlation of protons and hyperons is presented and used to study the p interaction. The measurement is performed with the ALICE detector in high-multiplicity triggered pp collisions at TeV. The hyperons are reconstructed using a missing-mass approach in the decay channel to with , while both and protons are identified using a machine learning approach. These techniques result in a high reconstruction efficiency and purity, which allows the measurement of the p correlation function for the first time. Thanks to the high significance achieved in the p correlation signal, it is possible to discriminate between the predictions of different models of the N interaction and to accomplish a first determination of the p scattering parameters