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Long‐Term Exposure of Bivalves to Ocean Acidification and Warming Under Ecologically‐Realistic Conditions Reveals Risks for Aquaculture by 2050 in the Mediterranean
No full textInternational audienceAbstract Bivalve mollusks are vital to coastal economies and food security, yet the impact of ocean warming and acidification on aquaculture remains unclear due to a lack of ground truth data on future production. Most experimental studies rely on short‐term, single‐factor experiments in stable and food‐unlimited environments, making it difficult to provide practical guidance to growers and decision‐makers. To address this knowledge gap, we developed a land‐based automated system to expose bivalves to future climate scenarios under field‐realistic conditions using unfiltered, ambient seawater, assessing survival, growth, reproduction, and next‐generation development. Here we present the first results of exposing Pacific oysters and Mediterranean mussels, the two most cultivated species in the Mediterranean area, to present conditions and projected scenarios for the years 2050, 2075, and 2100. For the first time, our results reveal that future warming and acidification conditions have a dramatic impact on the production yield of oysters and mussels. Oysters exposed to conditions projected for 2100 exhibited a 7% reduction in survival and a 40% reduction in growth rate, along with lower reproductive maturity, which in turn negatively affected the early development of their offspring. Mussels are already experiencing summer temperatures above their upper thermal limits, with around 40% mortality observed under current conditions and near‐total mortality under those projected for 2050. These patterns reflect sporadic mass‐mortality events reported elsewhere in the Mediterranean and indicate that mussel farming in the region could be severely compromised by mid‐century. Our results urgently call for the development of adaptation strategies in the Mediterranean
La police des débits de boissons exclut l'intervention de la police municipale à moins d'un péril imminent
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Apixaban or rivaroxaban for extended anticoagulation in patients with venous thromboembolism: A post hoc analysis of the renove clinical trial
No full textInternational audienceBackground: Apixaban and rivaroxaban are approved for the initial and extended treatment of venous thromboembolism (VTE). Both drugs have shown similar efficacy to prevent recurrent VTE, but cohort studies and a recent randomized controlled trial (RCT) suggest that, over the first 3 months of treatment, rivaroxaban use is associated with a significantly higher risk of clinically relevant bleeding (CRB) than apixaban. Whether the same phenomenon is observed during extended treatment, either at full or reduced dose, is unknown. Methods: The RENOVE open-label multicenter RCT compared full-dose vs reduced-dose direct oral anticoagulants in patients with VTE who had completed at least 6 months of full-dose treatment and had an indication for extended anticoagulation (Lancet 2025, doi: 10.1016/S0140-6736(24)02842-3). Apixaban or rivaroxaban were permitted in the trial, and randomization was stratified according to the drug used. In this post hoc analysis, we aimed to compare the risk of bleeding between patients who received full-dose apixaban (5 mg bid) vs full-dose rivaroxaban (20 mg daily), and in patients who received reduced-dose apixaban (2.5 mg bid) vs reduced-dose rivaroxaban (10 mg daily). The primary endpoint for this analysis was CRB, and the primary outcome measure was the 5-year cumulative incidence of CRB. The incidence of recurrent VTE, major bleeding, the composite of CRB and recurrent VTE, arterial events and death from any cause were secondary outcome measures. Except for the effect of dose reduction, hazard ratios (HR) were adjusted on center, age, sex, BMI, and use of antiplatelet drugs. Results: Of 2,768 patients in the intention-to-treat population, 1,385 patients assigned to full-dose received apixaban (n=630) or rivaroxaban (n=755), and 1383 patients assigned to reduced-dose received apixaban (n=625) or rivaroxaban (n=758). Baseline characteristics were broadly well-balanced between patients given apixaban or rivaroxaban, but median age (66.5 vs 62.6 years), the proportion of women (38.7 vs 32.1%) and proportion of patients with BMI ≥30 kg/m² (32.6 vs 28.8%) were slightly higher in patients given apixaban than in those given rivaroxaban. The maximum follow-up was 5 years, with a median of 37 months. In the full-dose subgroups, the 5-year cumulative incidence of CRB was 16.5% in patients given apixaban vs 14.4% in patients given rivaroxaban (adjusted HR [aHR] 1.02, 95% confidence interval [CI] 0.72-1.43). In the reduced-dose subgroups, the 5-year cumulative incidence of CRB was 11.0% in patients given apixaban vs 9.0% in patients given rivaroxaban (aHR 1.31, 95% CI 0.85-2.01). The 5-year cumulative incidence of major bleeding events was not significantly different between patients on apixaban or rivaroxaban, both in the full-dose subgroups (4.6% vs 3.5%, respectively, aHR 1.35, 95%CI 0.69-2.67) and reduced-dose subgroups (3.0% vs 1.6%, respectively, aHR 0.85, 95%CI 0.28-2.59). The 5-year cumulative incidence of recurrent VTE in the full-dose subgroups was 2.0% with apixaban vs 1.7 % with rivaroxaban (aHR 1.22, 95% CI 0.37-3.99), and 1.4% vs 2.7% in the apixaban and rivaroxaban reduced-dose subgroups, respectively (aHR 0.85, 95%CI 0.32-2.28). There was no significant difference between the two drugs at full or reduced dose in the incidence of the composite of CRB and recurrent VTE, arterial thromboembolic events, and death from any cause. Finally, the effect of dose reduction was consistent across the two drugs regarding the risk of CRB (aHR 0.68 [95%CI 0.47-0.98] for apixaban vs 0.57 [0.40-0.81] for rivaroxaban), the risk of VTE recurrence (aHR 1.33 [0.42-4.19] for apixaban vs 1.34 [0.55-3.27] for rivaroxaban), and the composite of CRB and VTE recurrence (aHR 0.74 [0.52-1.05] for apixaban vs 0.64 [0.46-0.89] for rivaroxaban). Conclusion: In this post hoc analysis of the strata of a large RCT of patients with VTE who had completed at least 6 months of full-dose anticoagulation and had an indication for extended treatment, apixaban and rivaroxaban showed similar safety profiles at 5 years, both in the full- and reduced-dose subgroups comparisons, while dose reduction showed similar benefit on CRB risk with both drugs. In contrast with the first months of full-dose anticoagulation, rivaroxaban proved as safe as apixaban during extended treatment, whether at full or reduced dose. Ideally, these results would need to be confirmed in a specific randomized trial
Synthesis Techniques for Spinel Nano-Ferrites
No full textInternational audienceDue to their magnetic and electrical properties, spinel ferrites are employed in magnetic recording medium, microwave devices, and sensors. Spinel ferrites can be synthesized utilizing solid-state reaction, sol-gel, co-precipitation, hydrothermal, and microwave-assisted processes. Each approach has pros and cons, and the choice depends on ferrite characteristics, cost, and synthesis ease. Synthesizing spinel ferrites with solid-state reaction is common, but it requires high temperatures and extended reaction periods. Sol-gel approach is easy and low temperature, allowing fine ferrite composition control. Another prominent process is co-precipitation, which generates homogeneous particles with narrow size distribution. Hydrothermal synthesis produces pure, crystallinity spinel ferrites under high pressure and temperature. New microwave-assisted synthesis speeds up and saves energy in spinel ferrite synthesis. Spinel ferrites are synthesized using several methods depending on their application and desired qualities
Contribution à la Compréhension des Mécanismes d’Endommagement des Structures Assemblées par Collage sous Chargements Multiaxiaux
No full textAdhesively bonded joints, widely used in industry, are subjected to complex multiaxial loadings. Predicting their failure relies on calculating the energy release rate (G). Our initial work focused on evaluating G for structural adhesives in mixed mode I+II, using classical linear elastic fracture mechanics methods (TDCB, MMB). To overcomethe limitations of these tests (e.g., substrate plasticization), we developed alternative methodologies based on the modified Arcan test. These last approaches allowed us to study the influence of temperature and fatigue loadings (for positive and negative ratios) on the energetic fracture envelope. Failure prediction techniques, based on the coupled criterion, were also developed. However, the assumption of linear elasticity for the adhesive can be restrictive. A preliminary evaluation of the impact of nonlinear behavior on the calculation of G via cohesive elements even suggested invariance of G with the mode ratio. To verify this observation, a calculation methodology for G based on an overall energy balance is proposed. Despite these advancements, in-depth exploration in the general mixed-mode I+II+III plane is crucial and lacking in most current analyses. The objective of this workis therefore to thoroughly investigate the damage mechanisms of adhesively bonded joints, in order to propose models capable of predicting their performance under a wide range of mechanical loadings.Les assemblages collés, essentiels dans l'industrie, sont soumis à des chargements multiaxiaux complexes. La prédiction de leurrupture repose sur le calcul du taux de restitution d'énergie (G). Les premiers travaux présentés ici ont porté sur l'évaluation de G pour des adhésifs structuraux en mode mixte I+II, en utilisant des méthodes classiques de la mécanique linéaire de la rupture (TDCB, MMB). Pour pallier les limites de ces essais (comme la plastification des substrats), des méthodologies alternatives ont été développées basées sur l'essai Arcan modifié. Ces approches ont permis d'étudier l'influence de la température et des chargements de fatigue (pour des ratios positifs et négatifs) sur l'enveloppe de rupture énergétique. Des techniques de prévision de rupture, fondées sur le critère couplé, ont également été développées. L’hypothèse d'élasticité linéaire pour l'adhésif peut toutefois être restrictive. Une évaluation préliminaire de l'impact du comportement non-linéaire sur le calcul de G par éléments cohésifs a même suggéré une invariance de G avec la mixité de modes. Pourvérifier cette observation, une méthodologie de calcul de G par bilan énergétique global est proposée. Malgré ces avancées, une explorationapprofondie dans le plan mixte général I+II+III est primordiale et fait défaut dans la plupart des analyses actuelles. L'objectif de ces travaux est donc d'investiguer en profondeur les mécanismes d’endommagement des assemblages collés, afin de proposer des modèles capables de prédire leur tenue sous une large gamme de sollicitations mécaniques
Effect of embodiment technique on the assessment of visuospatial memory in virtual and augmented reality
No full textInternational audienceThis study examines the effect of embodiment technique on spatial memory performance in virtual and augmented reality. Thirty participants were randomly assigned to three experimental conditions: virtual reality with controllers, virtual reality with virtual hands, and augmented reality with the real body. Participants performed a task adapted from the Corsi block-tapping test. Performance was assessed through spatial span, response time, and the evaluation of the sense of embodiment. Results revealed no significant effect of embodiment technique on recall performance. However, a significant effect was observed on completion times, with participants in the AR condition being slower than those in the other conditions. These findings suggest that embodiment technique does not influence spatial memory capacity in this type of task but may affect execution dynamics.Cette étude examine l'effet de la technique d’incarnation sur les performances de mémorisation spatiale en réalité virtuelle et augmentée. Trente participants ont été répartis aléatoirement dans trois conditions expérimentales : réalité virtuelle avec manettes, réalité virtuelle avec mains virtuelles et réalité augmentée avec corps réel. Les participants ont réalisé une tâche adapté du test des blocs de Corsi. Les performances ont été mesurées à travers l’empan spatial, le temps de réponse, ainsi que l'évaluation du sentiment d’incarnation. Les résultats ne révèlent aucun effet significatif de la technique d’incarnation sur les performances de rappel. Toutefois, un effet significatif a été observé sur les temps de réalisation, les participants de la condition RA étant plus lent que ceux des autres conditions. Ces résultats suggèrent que la technique d'incarnation n'influence pas la capacité de mémorisation spatiale dans ce type de tâche, mais peut influencer la dynamique d’exécution
Du jamaïcain au breton. Trajectoire d’une Anglaise en formation pour apprendre le breton
No full textInternational audiencePoltred sokiologelSociological portraitPortrait sociologiqu
L'insuffisance professionnelle d'un agent contractuel justifiant son licenciement doit être appréciée sérieusement et pendant une période raisonnable
No full textInternational audienceNote sous CAA Bordeaux, 4 février 2025, no 23BX00203, Commune de Bella
Diminuer les freins pour engager dans le don de plasma : évaluation d'un flyer expérimental
No full textInternational audienceObjectives. This study aimed to measure the psychometrics qualities of an extended model of the Theory of Planned Behavior (TPB) applied to plasma donation, and its relevance in the evaluation of interventions aiming at converting whole-blood donors (WBD) to plasma donation.Methods. Two studies were conducted. The first (N = 433) compared the efficacy of two communication strategies (standard strategy centered on motivations to donate vs. experimental strategy centered on barriers to donate) for influencing specific determinants of the extended model of the TPB and for engaging WBD in plasma donation. The second study (N = 309) evaluated the gain of adding to the experimental strategy an implementation intentions protocol to facilitate the behavior.Results. Study 1 showed the relevance of the extended model as a measurement tool of intention’s determinants, and the efficacy of the experimental strategy compared to the standard approach to bolster intention, F(2,430) = 7.03, p < 0.001, partial η2 = 0.032, and to increase the likelihood of commitments χ2(2, N = 433) = 11.904, p = 0.003, Cramer’s V = 0.17. Study 2 replicated these results but did not demonstrate any effect of the implementation intentions protocol to strengthen the intervention, χ2(1, N = 188) = 1.341, p = 0.25.Conclusions. These studies showed that addressing barriers to donation is an efficient communication and recruitment strategy. We encourage blood collection agencies to develop communication campaigns in this direction rather than focusing on donors motivations
