Portail HAL UPEC
Not a member yet
55480 research outputs found
Sort by
Surface tension enhancement in nanoconfined water: The role of confinement and excluded volume effects
No full textInternational audienc
Uncovering hidden sensitivity: Inter-individual growth variation in earthworms under fungicide exposure
No full textInternational audienceEnvironmental risk assessments (ERAs) of chemicals typically rely on standardized ecotoxicological tests that overlook inter-individual variability, despite its importance in ecological resilience and evolutionary success. Contaminants can disrupt individual differences by altering life-history traits, amplifying fitness disparities, favoring certain phenotypes, and reducing genetic diversity, ultimately impacting population dynamics and adaptability. However, the extent to which pollutants influence inter-individual variability and its population-level consequences remains poorly understood. To address this, our study examines the inter-individual variability of growth trajectories in the earthworm Aporrectodea caliginosa in response to sublethal exposure to the two active substances of Swing® Gold fungicide. Using a longitudinal design with 30 exposed and 30 unexposed individuals, we compared mean and inter-individual growth rate variability. While the fungicide had a weak effect on the cohort’s mean growth rate, we observed a three-fold increase in inter-individual variability in the exposed group. This increase highlighted a subset of highly sensitive individuals, whose growth was reduced by up to 10% compared to the average response. Our results suggest that focusing solely on population mean effects could overlook impacts on sensitive individuals, who could serve as early indicators of environmental stress. Incorporating individual variability into ecotoxicological studies is challenging due to the labor-intensive nature of individual monitoring and the need for larger datasets. Nonetheless, these efforts are essential for refining higher-tier ERA frameworks, improving safety factors for intraspecies variability, and defining regulatory thresholds. A better understanding of how contaminants affect inter-individual variation will enhance the accuracy and ecological relevance of risk assessments, ultimately capturing the long-term implications for population and ecosystem dynamics
Enhanced lithium storage of LiTi(HPO3)2 anode probed by in-situ X-ray diffraction and ex-situ X-ray photoelectron spectroscopy
No full textInternational audienceIn this study, the electrochemical behavior of LiTi(HPO3)2 is investigated through in situ XRD and ex-situ XPS. The results indicate that, in the first lithiation, LiTi(HPO3)2 undergoes an irreversible amorphization accompanied by a partial conversion reaction, with Ti3+/Ti2+ and P3+ as active redox centers. Besides, to enhance its performance, LiTi(HPO3)2 material was coated by rGO via a simple two-step hydrothermal method. Electrochemical evaluation revealed a notable improvement in capacity, cycling stability, and rate capability, with the optimized material delivering a reversible capacity of 450 mAh/g at 0.2C. This constitutes a pioneering advancement in the understanding of lithium storage mechanisms in lithium titanium phosphite-based anode materials, offering valuable insights into their electrochemical behavior and structural evolution
Le coeur du capital: Ces travailleuses de l’ombre qui font tourner le monde
No full textInternational audienceOn croise certaines d’entre elles sans les voir : tôt le matin dans le métro, tard le soir à la sortie d’un hôtel, d’un hôpital ou de bureaux.Qui sont ces femmes qui portent à bout de bras l’économie capitaliste, depuis ses coulisses ?Elles prennent en charge les tâchesde soin, d’éducation, de ménage.Elles sont peu visibles, peu considérées, mal rémunérées,mais elles constituent pourtantle « coeur » du capital. Sans elles, pas de force de travail, pas d’économie : c’est ce qu’on appelle le travail reproductif.Cet essai écrit à quatre mains croise les apports des féminismes, de l’économie et de l’histoire des luttes sociales, pour mettre en lumière ce travail de l’ombre.Une puissante critique du capitalisme, enracinée dans l’expérience concrète de millions de personnes, qui enjoint les lecteurs et lectrices à réinventer l’organisation du travail et de la société tout entière
Cardiovascular Magnetic Resonance Late Gadolinium Enhancement Risk Score for Mortality in Patients with Hypertrophic Cardiomyopathy: the HCM-LGE Risk Score
No full textInternational audienceBackground: The concept of “late gadolinium enhancement (LGE) granularity” using cardiovascular magnetic resonance (CMR) has been described as a strong prognosticator for patients with cardiomyopathy.(1, 2) No score has been developed using LGE in patients with hypertrophic cardiomyopathy (HCM) for clinical routine.The aim of the study was to develop and validate a score using the “LGE granularity” concept to predict mortality in HCM patients.Methods: The study cohort was based on the multicentric HCM-LGE registry, that included 2,873 patients with HCM referred for CMR between 2008 and 2021 in three French centers. The HCM-LGE risk score was developed using multivariable Cox coefficients of the “LGE granularity” concept from the training cohort (N=1,609). Then, this score was evaluated by time-dependent AUCs, precision recall curves, and calibration at 5 years on testing (N=199) and external validation (N=272). The primary outcome was all-cause mortality using the French National Death Registry. Based on the HCM-LGE risk score, patients were classified into 3 risk groups: low-risk (≤3 points), intermediate-risk ( >3 and ≤5 points), and high-risk ( >5 points). Survival probabilities were estimated using the Kaplan-Meier method and compared with the log-rank test.Results: The HCM-LGE risk score showed good performance in time-dependent analysis, with AUC of 0.72 (95% CI: 0.65, 0.79) and precision-recall AUC of 0.52 (95% CI: 0.48-0.56) in the external validation cohort. Cox analysis showed escalating risk from intermediate-risk (aHR: 2.61, [95% CI: 1.33-5.15]) to high-risk patients (aHR: 3.50, [95% CI: 1.90-6.45]; both p< 0.001). The HCM-LGE risk score showed the best improvement in model discrimination and reclassification above traditional prognosticators (Harrell’s C-statistic improvement: 0.09; NRI=50%; IDI=17%, all p< 0.001).Conclusion: The HCM-LGE risk score is a straightforward and reliable mortality risk prediction score for patients with HCM using readily available LGE parameters, with an incremental prognostic value above traditional prognosticators
Critical review of the latest advances in thermal management techniques for PEM fuel cells
No full textInternational audienc
La protection du patrimoine professionnel des époux : le sort des stock-options et des actions gratuites en régime de communauté
No full textInternational audienc
Inpainting of sparse tracks image satellite using Plug and Play and learned prior
No full textInternational audienceWe propose a novel method for reconstruction of high-resolution Sea Surface Height (SSH) fields from sparse along-track satellite altimetry. We explore the usage of an observation-driven deep-learning method for inpainting, with a focus on diffusion-based generative models for spatial reconstruction and data assimilation. The study includes data preparation from reanalyses and satellite observations, the definition of evaluation metrics relevant to oceanography, and comparison with baselines. We discuss model design choices, uncertainty characterization through stochastic sampling, and limitations in real-world deployment. Effectively, in this work, we develop and validate an observation-driven prior, allowing us to sample from the ground-truth distribution of SSH. By not relying on simulation results for training, we propose a step towards observationdriven Deep-Learning analysis of SSH and its uncertainties at small scale
Single-Dose Monocrotaline Pyrrole Injection as a Model of Pulmonary Endothelial Injury In Mice
No full textMonocrotaline (MCT) is a plant substance that induces severe pulmonary hypertension in several animals except for mice. The aim of our study was to state whether monocrotaline pyrrole (MCTp), the main monocrotaline metabolite, could induce significant injury in mouse lung when given intravenously. MCTp caused moderate pulmonary inflammation, remodelling of small distal vessels (percentage of muscularized arteries: 33,5 vs 20,6%, p≤0,0006) and a right ventricular dysfunction (RVSP 27,8mmHg vs 16,4mmHg, p≤0,0001; Fulton index 0,35 vs 0,26, p≤0,0007). These vascular effects were associated with a decrease in eNOS protein expression in lung tissues and resolved after 45 days. In conclusion, we developed a model of endothelial dysfunction and transient pulmonary hypertension in mice.</div
Strengthening climate resilience through an approach based on care, cultural rights, and social innovation.: The case of the Kerkennah islands’ communities
No full textInternational audienceThe purpose of this article is to demonstrate how, in the face of systemic challenges posed by climate change, triangulating the contributions of theoretical approaches based on care, cultural rights, and circular social innovation should enable a response to urgent territorial resilience challenges. Preliminary results from ongoing action-research on the Kerkennah Islands (which show strong symptoms of emblematic contemporary crises) suggest that reconnecting with mutual care practices and endogenous knowledge could constitute essential levers to rethink community regeneration and development strategies founded on local and participatory roots