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Experimental data-driven modeling and prediction of (γ,n) cross-sections with Physics-Informed Neural Networks and Gradient Boosted Decision Trees
No full textInternational audienceIn this study, we present a hybrid machine learning framework for modeling and predicting (γ,n) reaction cross sections across the nuclear chart, combining physical interpretability with predictive power. The first stage uses a Physics-Informed Neural Network (PINN) to fit experimental data from EXFOR while enforcing domain-specific constraints, such as energy thresholds, Lorentzian resonance behavior, and monotonicity beyond the Giant Dipole Resonance (GDR). These high-quality fits are then used to train a Gradient Boosted Decision Tree (GBDT) model on a broad set of nuclear features including mass, shell effects, separation energies, and deformation parameters. The resulting model agrees well with both experimental and evaluated data for known isotopes and extrapolates plausibly to exotic nuclides lacking measurements. Case studies on stable isotopes, actinides, and neutron-rich nuclei demonstrate the model’s robustness. This approach illustrates the complementarity of physics-informed and data-driven modeling for improving cross-section coverage in nuclear physics, simulation, and security applications
Incomplete lytic cycle of a widespread Bacteroides bacteriophage leads to the formation of defective viral particles
No full textInternational audienceAdvances in metagenomics have led to the identification of new intestinal temperate bacteriophages. However, their experimental characterization remains challenging due to a limited understanding of their lysogenic-lytic cycle and the common lack of plaque formation in vitro. In this study, we investigated the hankyphage, a widespread transposable phage of prominent Bacteroides symbionts. Hankyphages spontaneously produced virions in laboratory conditions even in the absence of inducer, but virions did not show any evidence of infectivity. To increase virion production and raise the chances of observing infection events, we identified a master repressor of the hankyphage lytic cycle, RepC HP , whose silencing amplified hankyphage gene expression, and enhanced replicative transposition and virion production. However, attempts to infect or lysogenize new host cells with different capsular types remained unsuccessful. Transmission electron microscopy and capsid DNA sequencing revealed an abnormal virion morphology and incomplete DNA packaging of the hankyphage, suggesting that it cannot complete its assembly in laboratory conditions for reasons that are yet to be identified. Still, metavirome and phylogenetic analyses were suggestive of hankyphage horizontal transmission. We could also detect the activity of diversity-generating retroelements (DGRs) that mutagenize the hankyphage tail fiber, and likely contribute to its broad host range. This study sheds light on the life cycle of this abundant intestinal bacteriophage and highlights important gaps in our understanding of the factors required for the completion of its life cycle. Elucidating this puzzle will be critical to gain a better understanding of the hankyphage biology and ecological role
Sodium-Glucose Cotransporter-2 Inhibitor in Diabetic and Nondiabetic Renal Transplant Recipients
No full textInternational audienceIntroduction: Sodium-glucose cotransporter-2 inhibitors (SGLT2i) improve cardiovascular prognosis in patients with chronic kidney disease (CKD), diabetes, and heart failure; and slow the decline of kidney dysfunction in patients with albuminuria. Although safety and efficacy of SGLT2i have not been investigated in kidney transplant recipients (KTRs), their marketing authorization leaves the possibility of their use in these patients in France.Methods: This was a prospective multicenter real-life study including all consecutive KTRs treated with SGLT2i.Results: We identified 347 KTRs treated with SGLT2i (97% with dapagliflozin), with an initiation of treatment most often beyond the first year after transplantation (87%). Importantly, 226 (65.1%) were diabetic and 245 (70.6%) were treated with angiotensin-converting enzyme (ACE) inhibitors or angiotensin-receptor blockers (ARBs). We found a low incidence of urinary tract infections (UTIs) (6.6%) and genital mycosis (0.6%), without any serious adverse event. Overall, SGLT2i were stopped in 54 patients (15.6%). The causes of SGLT2i discontinuations were very diverse. The main causes were graft dysfunction (32%), intercurrent infections (17%), urinary infections (11%), and digestive symptoms (9%). KTRs with a low estimated glomerular filtration rate (eGFR), especially those with eGFR < 30 ml/min per 1.73 m2, presented with the highest incidence of SGLT2i discontinuation (P = 0.003). SGLT2i were associated with a reduction in proteinuria, found in both diabetic and nondiabetic KTRs. In addition, they had an antihypertensive effect restricted to uncontrolled-hypertensive patients.Conclusion: SGLT2i have been used in KTRs since their authorization in France. They were discontinued more frequently in patients with impaired graft function; however, the expected side effects were infrequent and not life-threatening. The short-term antiproteinuric and antihypertensive effects are promising
Endurance Athletes Are More Resistant to Mental Fatigue Than Nonathletes
No full textInternational audiencePurpose: Acute mental fatigue refers to a temporary decline in cognitive function resulting from prolonged mental effort pertaining to a cognitively demanding task. Previous studies have indicated that acute mental fatigue decreases performance on subsequent physical effortful tasks as well as the capacity and/or motivation to invest mental effort. Scholars have recently suggested that aerobic training can enhance willpower. We hypothesized that endurance athletes are less responsive to the detrimental effects of acute mental fatigue than are nonathletes.Methods: Two groups of participants (50 athletes vs. 50 nonathletes) completed a sequential task protocol involving 30 minutes of a modified computerized incongruent Stroop task (effortful task) and 30 minutes of watching a documentary (control task), which were counterbalanced between two separate sessions; these tasks were followed by a time-to-exhaustion (TTE) handgrip task at 13% of participants' maximal voluntary contraction (dependent task). Psychophysiological indices (preejection period, heart rate variability, and respiratory rate) were assessed continuously throughout the experiment.Results: The behavioral results indicated that only nonathletes exhibited worse performance on the TTE handgrip task after performing the Stroop task. The performance of participants in both groups was similarly impacted by mental fatigue during the Stroop task, and all the participants reported higher levels of subjective fatigue after completing the Stroop task. The psychophysiological data suggest that sympathetic activity decreased over time during these two cognitive tasks due to habituation (i.e., decreased arousal).Conclusion: Overall, these results suggest that endurance athletes are less susceptible to the negative effects of acute mental fatigue
Redécouvrir Guillaume de Machaut par la VR : le projet Virtual Machaut
No full textInternational audienceL’exposition Virtual Machaut est un projet en réalité virtuelle réalisé conjointement parle Département de musique et musicologie de Metz et l’École Nationale Supérieure des Arts et Métiers. Son objectif est d’introduire les visiteurs dans une salle numérique 3D entièrement consacrée à la vie et l’œuvre de Guillaume de Machaut, célèbre compositeur de la fin du MoyenÂge. Cette présentation aura pour but d’introduire les différents axes de recherches menés par les étudiants en L3 de musicologie, les ressources créées ainsi que les avancées de l’ENSAM en matière de modélisation
On the nature and covariates of workaholism profiles: A generalizability study across distinct types of employees
No full textInternational audienceWe used a person-centered approach to identify the profiles of workaholism observed in six samples, including 12 subsamples, of employees (N = 7944). These profiles were defined while considering workers' global levels of workaholism, together with their specific levels of motivational, cognitive, emotional, and behavioral workaholism. We also considered the extent to which these profiles and their relations with covariates (workfamily conflict, harmonious passion, and obsessive pas-</div
Mise en place et utilisation de méthodes de mesures électriques linéaires et non-linéaires pour la caractérisation de matériaux fonctionnels et de dispositifs associés
No full textReporting of cluster randomised crossover trials 2023: extension of the CONSORT 2010 statement with explanation and elaboration Name / Job title Affiliation
No full textInternational audienceThe cluster randomised crossover (CRXO) trial has been gaining popularity over time due to the design's methodological strengths as compared with other cluster randomised designs (i.e. increased statistical efficiency, reduced risk of chance imbalances in cluster characteristics). The design has allowed randomised evaluation of interventions directed at clusters which otherwise could not have been undertaken due to the availability of too few clusters to achieve the desired power (e.g. when there are a limited number of intensive care units within a country). There are many methodological complexities in the design, conduct and analysis of the CRXO trials that requires tailored reporting guidance. We report a CONSORT extension for the CRXO trial design. The reporting guideline brings together advice from relevant CONSORT statements and addresses issues unique to the CRXO design. Coupled with this, new items, and amendments to others, reflect evolving requirements of the scientific community. The CONSORT CRXO extension includes a checklist of 28 items (with a total of 43 sub-items), along with a separate checklist for journal and conference abstracts, and sample size items
Discarded intravenous medication in the ICU: the GAME-OVER multicenter prospective observational study
No full textInternational audienceBackground: Medication waste is a contributor to the healthcare environmental footprint and impacts ecosystems. Data on medication waste in the intensive care unit (ICU) are scarce, and therefore are essential to develop new sustainable strategies.Methods: The GAME-OVER French multicenter prospective observational study was conducted from November 2022 to March 2023, over a 24-h period of choice, at the discretion of each participating center. Adult ICUs were enrolled in the study on a voluntary basis and hospitalized patients who did not express opposition were included in the analysis. The primary endpoint was the percentage of discarded intravenous (IV) medication in the ICU, defined as the ratio of the discarded volume to the total volume of IV medication prepared. Secondary endpoints included identifying risk factors and main reasons for medication waste and estimating its related healthcare cost.Results: Among the 81 ICUs and the 1076 enrolled patients, 408.9 L of 130 IV medications were prepared. The discarded volume was 43.8 L, resulting in a 10.7% discarded IV medication (95% Confidence Interval (CI), 9.9-11.5). Number of daily admissions/discharges in the ICU, as admission for elective surgery, Sequential Organ Failure Assessment score ≥ 7, endotracheal intubation, renal replacement therapy and body mass index were independently associated with increased discarded IV medication. Ninety percent of pharmaceutical waste was attributed to 25 key drugs, with an estimated national annual cost of 2,737,163€.Conclusions: Discarded intravenous medication in the ICU is considerable and results in significant costs for the health care system, without obvious patient-centered value. Risk factors associated with medication waste were largely nonmodifiable, emphasizing the need for sustainable practices in patient care and resource management.</b
Modélisation thématique des rivalités USA - Chine au sujet de L’IA dans l’économie (NLP & TAL)
No full textCet article à pour but de modéliser et d’analyser la nature de la rivalité USA-Chine dans le domaine économique à propos de l’IA. Nous avons scindé notre analyse en deux avec d’un côté les articles en langue anglaise et de l’autre les articles en langue chinoise. Pour chacun des deux corpus nous avons procédé à la modélisation des thématiques ainsi qu’à l’analyse textométrique. Nos analyses ont montré que l’intelligence artificielle représente un enjeu majeur mobilisant diverses forces à plusieurs niveaux : sur le plan macroéconomique, elle nécessite un fort engagement des acteurs de la finance, tandis que sur le plan stratégique, elle implique directement les États