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Computing isogenies from modular equations in genus two
No full textInternational audienceWe present an algorithm solving the following problem: given two genus 2 curves over a field k with isogenous Jacobians, compute such an isogeny explicitly. This isogeny can be either an l-isogeny or, in the real multiplication case, an isogeny with cyclic kernel; we require that k have large enough characteristic and that the curves be sufficiently generic. Our algorithm uses modular equations for these isogeny types, and makes essential use of an explicit Kodaira--Spencer isomorphism in genus 2
Solid-state chemistry of inorganic fluorides: From tungsten-bronze types to functionalized nanofluorides: A review
No full textThe author dedicates this review to the memory of Paul Hagenmuller (1921–2017) and Neil Bartlett (1936–2008), pioneers in solid state chemistry and in fluorine chemistry. ICMCB's colleagues Alain Demourgues, Etienne Durand, Damien Dambournet, Nicolas Penin, and my great friend Jean Grannec (1940–2023), members of the ICMCB Fluorine Group, are deeply acknowledged for their strong and fruitful contributions in these studies. Many thanks also to Henri Groult (Sorbonne Univ., Paris) for electrochemical investigations, Marc Leblanc and Vincent Maisonneuve (Univ. Le Mans, France) for sharing their extensive knowledge of fluoride structural networks, and my “old” colleague and friend Jacques Darriet for outstanding structure determinations. Concerning the different topics presented in this review, scientific cooperations have been established with scientists worldwide, such as Igor N. Flerov and Kirill S. Aleksandrov (1931-2010) (Kirensky Institute of Physics, Krasnoyarsk, Russia), Larisa Demyanova (Russian Academy of Sciences, Blagoveshchensk, Russia), Pavel Fedorov, (Russian Academy of Sciences, General Physics Institute, Moscow, Russia), Erhard Kemnitz and Michael Feist (Humboldt University, Berlin, Germany), Dietrich Babel and Werner Massa (Philipps Univ., Marburg, Germany), Boris Žemva (1940–2023) and Karel (Drago) Lutar (1947–2000) (Jožef Stefan Institute, Ljubljana, Slovenia), Tsuyoshi Nakajima (Aichi Institute of Technology, Japan), Hidekazu Touhara (Shinshu Univ., Japan).International audienceSolid-state chemistry of inorganic fluorides has gained great importance in the second half of 20 th century. It aims at identifying the relationships between the structural networks and the physical properties resulting from interactions within these networks. One of the most significant results was the discovery in the 1960s of series of AxMF3 fluorides with structures similar to those of tungsten oxide bronzes. The investigation of other compounds mainly based on Al, Ga and transition metals with structures derived from ReO3 , hexagonal tungsten bronze (HTB), tetragonal tungsten bronzes (TTB), defect pyrochlore and perovskite was soon launched in relation, in a first step, to their magnetic properties. Such interest was further extended to various properties such as positive electrodes in Li-ion batteries, UV absorbers, multiferroic components. Today, solid-state inorganic fluorides are present at the nano-sized level as components in many advanced technologies, including Li batteries or all solidstate fluorine batteries, micro-or nano-photonics, up-or down-conversion fluorescent probes, solid-state lasers, nonlinear optics, nuclear cycle, superhydrophobic coatings, etc. It has been pointed out that most of these outstanding properties can be correlated to the exceptional electronic properties of elemental fluorine, F2 .The aim of this article is to review the solid-state chemistry of fluorides having the formula AxMF3 over several decades, from their discovery in the 1960s to the interesting physical-chemical properties more recently investigated on these phases that derive from the ReO3 , perovskite, defect-pyrochlore, hexagonal-and tetragonaltungsten bronze types.</div
Plasmonic photoconductive terahertz source array for multi-spectral imaging
No full textInternational audienceTo address the limitations of existing terahertz time-domain imaging systems, we present a new terahertz source array based on plasmonic nanoantenna arrays that offer efficient optical-to-terahertz conversion. As a first proof-of-concept, we use a terahertz time-domain spectroscopy system with the terahertz source array and a single pixel detector to capture multi-pixel hyperspectral terahertz images without requiring raster scanning. We demonstrate that the imaging system can capture both amplitude and phase information by acquiring far-field images of different phase and amplitude objects. The introduced terahertz source array has the potential to realize high-throughput, high-SNR and high-resolution imaging and inspection systems, benefiting from the unique features of terahertz waves
Recommended moderate to vigorous physical activity levels for people in the chronic phase of stroke can be achieved in outpatient physiotherapy: a multicentre observational study
No full textInternational audienceBACKGROUND: Rehabilitation in the chronic phase of stroke should include 20 minutes of moderate to vigorous physical activity (MVPA). However, the level of compliance with MVPA guidelines in outpatient physiotherapy is unknown. OBJECTIVES: To investigate (1) whether people in the chronic phase of stroke perform the recommended 20 minutes of MVPA during outpatient physiotherapy sessions in France, (2) whether the person's clinical characteristics influence MVPA time and (3) which interventions contribute to achievement of recommended MVPA time. METHODS: This was a multicentre, cross-sectional observational study of routine outpatient physiotherapy sessions in France in people in the chronic phase of stroke. The main measures included MVPA time (determined using a heart rate monitor), clinical tests and types of physiotherapy interventions (recorded by external investigator during 2 sessions for each participant). RESULTS: 84 people in the chronic phase of stroke and 152 outpatient physiotherapy sessions in 29 outpatient clinics were included (2021-2022). Median (interquartile range) MVPA time was 25 (7-45) minutes across all sessions. Fifty-nine percent of the sessions fulfilled MVPA guidelines. Among clinical tests, only the Mini-Mental Scale Examination was significantly associated with MVPA time. Endurance, balance, and functional lower limb training were associated with the achievement of MVPA guidelines. CONCLUSION: Outpatient physiotherapy sessions have the potential to meet the MVPA guidelines. Further research is needed to understand the variability of compliance with MVPA guidelines and to develop strategies to increase the integration of MVPA into outpatient physiotherapy sessions
Is pressure necessary to solve incompressible Navier-Stokes equations?
No full textThe three components of the Navier-Stokes equations in their incompressible formulation are subject to a constraint on the divergence of velocity. The idea proposed here is to replace the pressure gradient in these equations with the dual curl of another function, the vector potential of acceleration. Since the divergence of the dual curl is intrinsically zero, the search for a solution on the velocity does not require the application of the associated incompressibility constraint. Discrete mechanics is the appropriate framework because the law of motion based on the conservation of acceleration takes the form of a Helmholtz-Hodge decomposition, the sum of a divergence-free component and a curl-free component. The form of the inertia terms, also expressed in the form of this decomposition, reveals the possibility of including the solenoidal term in the dual curl, which paves the way for an extended treatment of incompressible inertial flows. The essential consequence is the abandonment of pressure and the resolution of a specific equation to maintain the incompressibility constraint over time. This formalism leads to an extension of the principle of relativity, which becomes a local principle. Two simple examples illustrate the behavior of the proposed formulation
Yercaud. Trajectoire d’une Hill Station. Des plantations coloniales au tourisme
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It's yours or you've got it? Inter-observer variability in typo-technology analysis
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Évaluation des besoins des pharmaciens en termes de collaboration et coordination avec les autres professionnels de santé au sein du territoire de la Communauté Professionnelle Territoriale de santé Entre-deux-Mers
No full textIntroduction: the French healthcare system faces growing challenges: an aging population, an increase in chronic diseases, technological advancements, financial constraints, and an unfavorable medical demographic evolution. To address these challenges, the "Ma santé 2022" plan was launched in 2019, aiming to reform the healthcare system by promoting the creation of territorial care teams, the Territorial Professional Health Communities (CPTS in french). Their objective is to establish an organizational and coordination space for healthcare professionals (HCPs) within the same territory. They bring together medical, social, and medico-social professionals around a shared health project, meeting the needs of the local population. Materials and Methods: a qualitative study using semi-structured interviews was conducted with 18 pharmacists in the territory. The collected data was analyzed thematically, allowing for the identification of the main needs and expectations of the pharmacists. Results: eighteen pharmacists from the twenty-five pharmacies in the territory were interviewed. The main points raised are as follows: - Knowledge and perception of CPTSs: Pharmacists have varying levels of knowledge about CPTSs, some are well-informed and actively involved, while others are completely unfamiliar with the concept. - Integration and recognition of the pharmacist’s expertise: Some pharmacists feel that they are not sufficiently consulted in the overall management of patients and are relegated to the role of mere medication dispensers. - Preferred collaboration with nearby professionals: Many pharmacists have an effective local professional network, especially with nearby physicians and nurses. - Identified needs: Pharmacists expressed the need for better coordination between community and hospital care, simplification of administrative and communication procedures, and continuing education adapted to the evolving nature of their profession. - Drawbacks encountered: The main obstacles to pharmacists’ engagement in the CPTS include lack of time, lack of clarity regarding their role, and difficulty in perceiving real benefits from their participation. Discussion: this study highlights the key issues concerning the integration of pharmacists into the care coordination dynamics in the Entre-Deux-Mers CPTS. The main points raised are: - Lack of recognition of the pharmacist's role - Difficulties in communication with other healthcare professionals - Limited access to information and tools of the CPTS - Interest in continuing education - and the organizational constraints Conclusion: this study emphasizes the importance of better integrating pharmacists into CPTS, taking into account their specific needs and expectations. Areas for improvement have been identified: - Clarification of roles and responsibilities - Development of interprofessional IT equipment - Involvement of a pharmacist in the management of the CPTS - Training adapted to the pharmacists’ obligations - Promotion of shared protocols and task delegation - Improvement in financial status of participating pharmacists. - In conclusion, the active participation of pharmacists in CPTS is essential to the improvement of care coordination and patient management in the Entre-Deux-Mers territory.Introduction : le système de santé français fait face à des défis croissants : vieillissement de la population, augmentation des maladies chroniques, progrès technologiques, contraintes financières et évolution démographique médicale défavorable. Pour y répondre, le plan « Ma santé 2022 » a été lancé en 2019, visant à réformer le système de santé en favorisant la création de collectifs de soins territoriaux, les Communautés Professionnelles Territoriales de Santé (CPTS). Elles ont pour objectif de constituer un espace d’organisation et de coordination des professionnels de santé (PDS) d'un même territoire. Elles regroupent des professionnels médicaux, sociaux et médico-sociaux autour d'un projet de santé commun, répondant aux besoins de la population locale. Matériels et méthodes : une étude qualitative par entretiens semi-dirigés a été menée auprès de 18 pharmaciens du territoire entre avril et juin 2024. Les données recueillies ont été analysées de manière thématique, permettant d'identifier les principaux besoins et attentes des pharmaciens du territoire de l’Entre-Deux-Mers. Résultats : 18 pharmaciens sur les 25 pharmacies du territoire ont été interrogés. Les principaux points soulevés sont : - Connaissance et perception des CPTS : les pharmaciens ont une connaissance variable des CPTS, certains étant bien informés et impliqués, tandis que d'autres ne connaissent pas du tout la CPTS. - Intégration et reconnaissance de l'expertise du pharmacien : certains pharmaciens estiment être peu consultés dans la prise en charge globale des patients et relégués à un rôle de simples dispensateurs de médicaments. - Collaboration privilégiée avec les professionnels de proximité : de nombreux pharmaciens ont un réseau de travail local efficace, en particulier avec les médecins et infirmiers proches. - Besoins identifiés : les pharmaciens ont exprimé le besoin d'une meilleure coordination ville-hôpital, d'une simplification des procédures administratives et de communication, et d'une formation continue adaptée à l'évolution de leur métier. - Freins à l’engagement : Le manque de temps, le manque de clarté quant à leur rôle et les difficultés à percevoir les bénéfices concrets de leur engagement sont les principaux freins à l'implication des pharmaciens dans la CPTS Discussion : cette étude met en évidence les enjeux clés concernant l'intégration des pharmaciens dans la dynamique de coordination des soins au sein de la CPTS de l'Entre-Deux-Mers. Les principaux points soulevés sont : - Le manque de reconnaissance du rôle du pharmacien - Les difficultés de communication avec les autres professionnels de santé - L'accès limité à l'information et aux outils de la CPTS - L'intérêt pour la formation continue - et les contraintes organisationnelles Conclusion : cette étude souligne l'importance d'une meilleure intégration des pharmaciens dans les CPTS, en tenant compte de leurs besoins et attentes spécifiques. Des pistes d'amélioration ont été identifiées : - Clarification des rôles et responsabilités - Développement d'outils numériques interprofessionnels - Implication d'un pharmacien dans la gouvernance de la CPTS - Adaptation des formations aux contraintes des officines - Promotion des protocoles partagés et de la délégation de tâches - Valorisation financière de l'engagement des pharmaciens En conclusion, la participation active des pharmaciens aux CPTS est essentielle pour améliorer la coordination des soins et la prise en charge des patients sur le territoire de l'Entre-Deux-Mers
Screening Mammography and Breast Cancer: Variation in Risk with Rare Deleterious or Predicted Deleterious Variants in DNA Repair Genes
No full textInternational audienceBackground: Women with a familial predisposition to breast cancer (BC) are offered screening at earlier ages and more frequently than women from the general population. Methods: We evaluated the effect of screening mammography in 1552 BC cases with a hereditary predisposition to BC unexplained by BRCA1 or BRCA2 and 1363 unrelated controls. Participants reported their lifetime mammography exposures in a detailed questionnaire. Germline rare deleterious or predicted deleterious variants (D-PDVs) in 113 DNA repair genes were investigated in 82.5% of the women and classified according to the strength of their association with BC. Genes with an odds ratio (OR) < 0.9 was assigned to the Gene Group “Reduced”, those with OR ≥ 0.9 and ≤1.1 to Group “Independent”, and those with OR > 1.1 to Group “Increased”. Results: Overall, having been exposed to mammograms (never vs. ever) was not associated with BC risk. However, an increase in BC risk of 4% (95% CI: 1–6%) per additional exposure was found under the assumption of linearity. When grouped according to D-PDV carrier status, mammograms doubled the BC risk of women carrying a D-PDV in Group “Reduced”, as compared to those carrying a D-PDV in Group “Increased”. Conclusions: Our study is the first to investigate the joint effect of mammogram exposure and variants in DNA repair genes other than BRCA1 and BRCA2 in women at high risk of BC; therefore, further studies are needed to verify our findings. Even though mammographic screening reduces the risk of mortality from BC, the identification of populations that are more or less susceptible to ionizing radiation may be clinically relevant
Optimizing CFD Configuration for Accurate Prediction of Wind Pressure Coefficients on Circular Arched Roof Structures
No full textInternational audienceThis study evaluates the influence of Computational Fluid Dynamics (CFD) configurations, including domain size, mesh resolution, and turbulence model, on the prediction of c_p (mean wind pressure coefficients) on circular arched roof structures, and determines the optimal configuration for accurate and efficient simulations. A parametric study was conducted using RANS-based CFD simulations for six different arched roof geometries. The downstream, lateral and upper sides of the computational domain were varied as geometry-based distances in order to assess flow stabilization and blockage effects. Four mesh densities proportional to the structure dimensions were assessed to obtain high accuracy with low-cost computational demand. Finally, five turbulence models were compared for their ability to predict wind pressure coefficients on six circular-arched roof geometries using statistical metrics. The results indicate that domain dimensions and mesh resolution have a slight impact on the accuracy of CFD predictions for arched roof geometries. A downstream domain length of 12S (where S is the greater of the total height and half the span) and a 3.45% blockage ratio provide a good compromise between accuracy and computational efficiency. A mesh resolution of 0.0125W (W is the average of the total height and half the span) based on the structure dimensions was found sufficient to meet the requirements of precision and low computational cost. Among the turbulence models, the Realizable model produced the most accurate results across all geometries, obtaining an average of 0.9 for R^2 and 0.25 for RSR, followed by the RNG model, whereas the Standard and SST models provide a good distribution but underestimate suction magnitude. Overall, the findings provide a guideline for efficient and accurate CFD simulations for arched roof structures, offering recommendations for domain size, mesh resolution, and turbulence model selection. These guidelines can improve the efficiency of future aerodynamic analyses of similar structural configurations