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Déploiement et Maillage de stations instrumentées en IoT sur le territoire pour diverses études_AG AnaEE 2026 "ECOLOGGING"
No full textInternational audienceIn this poster, we present the deployments of the different types of instrumented stations developed within the framework of the "ECOLOGGING” project, carried out during the year 2024/2025, as well as the main developments, the results obtained, and the conclusions. The “ECOLOGGING” stations are deployed according to the nature of the studies conducted and the associated specific scientific needs.Dans ce poster, nous présentons les déploiements des différents types de stations instrumentées développées dans le cadre du projet "ECOLOGGING", réalisés au cours de l’année 2024/2025, ainsi que les principales évolutions, les résultats obtenus et les conclusions. Les stations ECOLOGGING sont déployées en fonction de la nature des études menées et des besoins scientifiques spécifiques associés
Separated determinantal point processes and generalized Fock spaces
No full textWe study conditions so that the determinantal point process associated to a generalized Fock space defined by a doubling subharmonic weight is almost surely a separated sequence in . Under a natural assumption on , we provide a characterization of such processes. Additionally, we emphasize the role of intrinsic repulsion in determinantal processes by comparing with the Poisson process of the same first intensity. As an application, we show that the determinantal process associated to the canonical weight , α>0, is almost surely separated if and only if α<4/3. In contrast, the Poisson process having the same first intensity as is almost surely separated if and only if α<1
Should Mycoplasma penetrans be considered a pathogen in anal specimens from men who have sex with men?
No full textInternational audienceObjectives: This study was performed to assess the prevalence of Mycoplasma penetrans in anal samples collected from men who have sex with men (MSM) undergoing screening for Chlamydia trachomatis and Neisseria gonorrhoeae and to identify factors associated with the presence of M. penetrans . Methods: From July to November 2022, all anal specimens from MSM submitted for C. trachomatis and N. gonorrhoeae detection as part of routine care were prospectively collected. M. penetrans was detected using a real-time PCR. Demographic, clinical, and biological data were obtained from the patients' medical records.Results: The prevalence of M. penetrans was 6.8% (23/338). No individuals reported anal symptoms. Having had a previous sexually transmitted infection within the past 12 months or a history of treated syphilis was associated with M. penetrans positivity ( P = 0.003). The prevalence of M. penetrans was 8.2% (18/220) among MSM living with HIV and 4.2% (5/118) among HIV-negative MSM ( P = 0.26). Conclusion: There is a strong association between behavioral factors in MSM and the detection of M. penetrans in anal samples. However, the findings suggest colonization rather than infection, indicating that this microorganism should not be regarded as a pathogen in anal specimens.</div
Carcinogenicity of atrazine, alachlor, and vinclozolin
No full textInternational audienceFrom October to November, 2025, a Working Group of 22 scientists from 12 countries met at the International Agency for Research on Cancer (IARC) in Lyon, France, to finalise their evaluation of the carcinogenicity of atrazine, alachlor, and vinclozolin
Kantorovich Distance via Spanning Trees: Properties and Algorithms
No full textWe study optimal transport between probability measures supported on the same finite metric space, where the ground cost is a distance induced by a weighted connected graph. Building on recent work showing that the resulting Kantorovich distance can be expressed as a minimization problem over the set of spanning trees of this underlying graph, we investigate the implications of this reformulation on the construction of an optimal transport plan and a dual potential based on the solution of such an optimization problem. In this setting, we derive an explicit formula for the Kantorovich potential in terms of the imbalanced cumulative mass (a generalization of the cumulative distribution in R) along an optimal spanning tree solving such a minimization problem, under a weak non-degeneracy condition on the pair of measures that guarantees the uniqueness of a dual potential. Our second contribution establishes the existence of an optimal transport plan that can be computed efficiently by a dynamic programming procedure once an optimal spanning tree is known. Finally, we propose a stochastic algorithm based on simulated annealing on the space of spanning trees to compute such an optimal spanning tree. Numerical experiments illustrate the theoretical results and demonstrate the practical relevance of the proposed approach for optimal transport on finite metric spaces.We study optimal transport between probability measures supported on the same finite metric space, where the ground cost is a distance induced by a weighted connected graph. Building on recent work showing that the resulting Kantorovich distance can be expressed as a minimization problem over the set of spanning trees of this underlying graph, we investigate the implications of this reformulation on the construction of an optimal transport plan and a dual potential based on the solution of such an optimization problem. In this setting, we derive an explicit formula for the Kantorovich potential in terms of the imbalanced cumulative mass (a generalization of the cumulative distribution in R) along an optimal spanning tree solving such a minimization problem, under a weak non-degeneracy condition on the pair of measures that guarantees the uniqueness of a dual potential. Our second contribution establishes the existence of an optimal transport plan that can be computed efficiently by a dynamic programming procedure once an optimal spanning tree is known. Finally, we propose a stochastic algorithm based on simulated annealing on the space of spanning trees to compute such an optimal spanning tree. Numerical experiments illustrate the theoretical results and demonstrate the practical relevance of the proposed approach for optimal transport on finite metric spaces
Teukolsky on slowly-rotating Kerr-de Sitter in the vanishing limit
No full textWe prove energy, Morawetz and rp-weighted estimates for solutions to the Teukolsky equation set on a slowly-rotating Kerr-de Sitter background. The main feature of our estimates is their uniformity with respect to the cosmological constant Λ>0 (thus allowed to tend to 0), while they hold on the whole domain of outer communications, extending up to r∼Λ−12. As an application of our result, we recover well-known corresponding estimates for solutions to Teukolsky on a slowly-rotating Kerr background in the limit Λ→0
Smartphone light-driven electrocatalytic polymerization of thiophenes
No full textInternational audienceHerein we take advantage of the photoelectric effect produced on light-emitting diodes to induce a kinetically controlled electrocatalytic polymerization of 3,4-alkoxythiophenes. Wireless polymerization was achieved by fine-tuning the irradiation time, the power density and the molecular structure of the thiophenes. A smartphone based light-driven system is introduced as a simple and low cost polymerization approach of π-conjugated films
On the performance of radiocarbon and quartz OSL dating in macrotidal estuarine environments: Four case studies from Western France
No full textInternational audienceThe study of estuarine sedimentary archives provides valuable insights into their geomorphological evolution over the past two centuries, enhancing our understanding of estuarine responses to climate change. Establishing a reliable and precise geochronological framework is therefore essential for monitoring these changes. This study evaluates the performance of quartz Single-Aliquot Regenerative (SAR) OSL and AMS 14C dating in four estuaries along the western coast of France. The results are compared with cartographic data, serving as an independent age control. Of the 14 OSL dated samples, 10 yield depositional ages consistent with cartographic data, whereas the remaining 4 appear to overestimate ages by 20–100 years. In contrast, AMS 14C dating reveals numerous stratigraphic inversions, with at least 12 out of the 16 measured samples overestimating the depositional age in some cases by up to 5000 years, in total disagreement with cartographic data. The discrepancy between the OSL and radiocarbon ages reflects the constant reworking of allochthonous material, to which is added the further uncertainty associated with the local reservoir age. These factors fundamentally limit the reliability of 14C dating regardless of the material analyzed. By contrast, the OSL signal displays remarkable resilience, with any age overestimation linked to partial bleaching remaining minor (on the order of decades) compared with the errors affecting 14C ages. This underscores the capacity of OSL dating to resolve short-term environmental changes and positions it as the most reliable tool for constructing high-resolution chronologies of the last centuries in macrotidal estuarine settings
Delayed Dental Development in Children With Non‐Syndromic Hypodontia: A Cross‐Sectional Study Using a Machine Learning Approach to Dental Age Estimation
No full textInternational audienceObjectives: To investigate the influence of non-syndromic hypodontia on radiographic dental development and to estimate dental age in children with bilateral mandibular agenesis using a machine learning approach.Materials and Methods: This retrospective cross-sectional study included 626 children aged 6–15 years (311 with dental agenesis, 315 matched controls). Dental age (DA) was assessed using the original Demirjian method. In cases with bilateral congenitally missing teeth in the mandible, DA was estimated using supervised machine learning models based on specific random forests, following a secondary-diagnosis approach. Dental developmental delay was calculated as the difference between dental and chronological age (DA–CA) and compared across groups defined by agenesis status, severity and pattern. Multiple linear regression was applied to evaluate the effects of hypodontia, sex, chronological age and their interactions on DA–CA.Results: Eight random-forest models were trained, achieving good age-prediction accuracy (MAE = 0.08–0.28 years, R2 > 0.95). A 0.77-year difference in dental development (95% CI 0.61–0.94) separated children with hypodontia from controls (p < 0.001). The regression model confirmed that agenesis status, sex and CA were significant predictors of DA–CA, with an interaction between sex and agenesis. Unilateral or bilateral agenesis of mandibular second premolars was associated with a dental developmental delay compared with controls (padj < 0.05).Conclusion: Our results were consistent with broader evidence linking hypodontia to altered developmental timing. Machine learning imputation offers a robust approach for missing teeth and can be implemented for age estimation in larger cohorts for orthodontic or forensic purposes