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Impact of pesticides, their mixture and transformation products on freshwater periphyton metabolism.
No full textInternational audiencePesticides are widely used in agriculture and often reach aquatic ecosystems where they can impact exposed organisms. During their transfer from fields to rivers, pesticides undergo abiotic degradation, forming transformation products (TPs), whose identities and toxicities are mostly unknown. Aquatic periphytons as a complex communities of microorganisms (e.g. microalgae, bacteria, etc.) playing a key role in ecosystem functioning. Thus, they are relevant for assessing impact of micropollutant on ecosystem functions. Despite increasing insights into chemical stressors, limited information exists about the combined effects of pesticides and their TPs on such microbial communities. To tackle this knowledge gap, our study investigates the toxicity of the herbicide terbuthylazine (TBA) and its TPs on periphyton using a multi-descriptors and metabolomics approach. Periphyton was exposed for four weeks to TBA, its TPs TBA-desethyl, and weathered TBA (wTBA), at two concentrations (5 and 150 µg/L). To reflect environmental conditions, TBA-desethyl was also tested in mixture with two ubiquitous contaminants glyphosate and AMPA (GA) at environmental levels. Control and GA-only treatments allowed for proper comparison. Results showed that most descriptors (e.g., photosynthetic yield, biomass, heterotrophic enzymatic activities) were strongly impacted by TBA but not or slightly by its TPs or mixtures with glyphosate. However, metabolomics revealed distinct profiles for each treatment, with TBA at 150 µg/L being the most disruptive. Interestingly, GA-containing mixtures showed no additional metabolic impact. These findings highlight metabolomics as a sensitive tool for detecting subtle effects of TPs and chemical mixtures, emphasizing its value in ecological risk assessments of aquatic microbial communities
Faire parler les artefacts et les vestiges mobiliers pour les recherches de provenance. Formalisation des données
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National survey on aspiration pneumonia in elderly hospitalized or institutionalized patients in France in 2023
No full textInternational audienceBackground: Aspiration pneumonia is not specifically addressed in French guidelines on pneumonia, despite it being a frequent infection affecting specific populations. The French Infectious Diseases Society's (French acronym SPILF) Recommendations Group and the Infectio-Geriatrics Group (GinGER-SPILF SFGG) have published the first recommendations on this topic in 2025. The objective of this study was to describe practices of French physicians to manage aspiration pneumonia in hospitalized or institutionalized people aged over 75 years.Methods: A nationwide survey conducted from June to November 2023 was distributed to physicians working in hospitals or medico-social facilities to assess their habits from diagnosis to prevention.Results: A total of 452 physicians responded (mainly geriatricians, infectious disease specialists, and family physicians). Diagnostic criteria were consensual: presence of vomiting, swallowing disorders, or a history of inhalation pneumonia. Seventy-eight per cent of physicians reported prescribing complementary examinations. Imaging examinations (74%) were prioritized over bacteriology (19%). Oral amoxicillin-clavulanic acid was the first-line antibiotic (82%). Significant differences were found in the use of metronidazole and of the subcutaneous route, which were more frequently used by geriatricians. Geriatricians referred significantly more patients to speech therapists. The most commonly used swallowing test was the water test (92%). Screening and management of swallowing disorders, secondary prevention, and nutritional management varied according to specialties and practice settings.Conclusion: This survey shows consensus regarding diagnostic criteria and antibiotic therapy. However, the significant variation in prevention and nutritional management across specialties and practice settings highlights the need for specific recommendations
Galactic transient sources with the Cherenkov Telescope Array
No full textInternational audienceA wide variety of Galactic sources show transient emission at soft and hard X-ray energies: low-mass and high-mass X-ray binaries containing compact objects (e.g., novae, microquasars, transitional millisecond pulsars, supergiant fast X-ray transients), isolated neutron stars exhibiting extreme variability as magnetars as well as pulsar wind nebulae. Although most of them can show emission up to MeV and/or GeV energies, many have not yet been detected in the TeV domain by Imaging Atmospheric Cherenkov Telescopes. In this paper, we explore the feasibility of detecting new Galactic transients with the Cherenkov Telescope Array (CTA) and the prospects for studying them with Target of Opportunity observations. We show that CTA will likely detect new sources in the TeV regime, such as the massive microquasars in the Cygnus region, low-mass X-ray binaries with low-viewing angle, flaring emission from the Crab pulsar-wind nebula or other novae explosions, among others. We also discuss the multi-wavelength synergies with other instruments and large astronomical facilities
Potential of thinning to increase forest resilience and resistance to drought, pest, windstorm and fire: A meta-analysis
No full textInternational audienceAs the pressure on forest ecosystems increases with the occurrence of more severe and frequent natural disturbances, the need for silvicultural treatments to mitigate multiple risks is becoming increasingly apparent. Thinning has been identified as a means of managing stands to enhance resilience and resistance to disturbances. However, the underlying mechanisms vary depending on the disturbance types and tree species and there is a lack of empirical evidence that thinning can effectively mitigate these risks at a broad scale. We conducted a meta-analysis of 50 studies quantifying the effects of thinning treatments on the resilience and resistance of forest stands to four categories of natural disturbances: drought, insects and pathogens, wind, and fire. Meta-analyses were conducted to examine the influence of various moderators, namely the response type (growth, survival, damage), thinning intensity, thinning type, time since the first treatment, stand age and pest type (for insects and pathogens). We found a positive broad-scale effect of thinning on forest resilience and resistance, while the disturbance-specific effect was positive for reducing the impact of drought, pests, and in some cases fire, but not significant for windstorms. Although responses varied among disturbance types, and in some cases response type, thinning type, and time since treatment, a key finding of this study is that no statistically significant negative effect of thinning has been detected with respect to our resilience and resistance indicators. Although thinning should not be considered as a tool that will singlehandedly increase the resilience of forests, our results suggest that for temperate and boreal ecosystems of North America and Europe, thinning can be expected to increase the resilience and resistance of forests to multiple stressors, in a wide range of sites and stand characteristics. Yet, empirical data from Asia, southern hemisphere and tropical forests are needed to enable global-scale conclusions. Moreover, potential detrimental effects of thinning on forest ecology should be carefully assessed before prioritizing thinning as a means of increasing forest resilience and resistance
La charge médicale des femmes : perception de médecins dans les départements des Pyrénées-Atlantiques et de Gironde
No full textIntroduction: gender inequalities remain a major issue in our society and are a source of women's mental burden. The medical burden refers to the mental load associated with managing household health. Through this study, we aimed to gather doctors' perceptions and experiences on this topic. We also analyzed the proposals from the doctors interviewed to combat this imbalance. Materials and Methods: we conducted a qualitative study through semi-structured individual interviews with general practitioners, pediatricians, and geriatricians working in the departments of Gironde and Pyrénées-Atlantiques. Results: 16 doctors were interviewed. All acknowledged the existence of this imbalance within their patient base, particularly concerning the management of children's health, partners’ health, or parents’ health. The various medical tasks were detailed, such as attending medical appointments or following vaccination schedules. According to the doctors, the origin of this imbalance is mainly historical and societal. It results in repercussions for women, affecting their mental and physical health, as well as their professional and family lives. Some doctors do not feel entitled to act in this situation, while others are not bothered by the imbalance and believe each household's organization should be respected. Finally, proposals were made to include fathers in the health of their children or partners in their own health. Public health awareness and prevention around this issue were also mentioned, starting from childhood. A screening by doctors for the impact on women's health was recommended, along with a proposal for physical and mental support if necessary. Discussion: the inequalities in the distribution of medical burdens within households were clearly recognized and detailed by the interviewed doctors. Prevention, awareness, and support initiatives could be implemented by doctors and health organizations to assist the women affected by this issue.Introduction : les inégalités entre hommes et femmes demeurent un enjeu majeur de notre société actuelle et sont à l’origine de la charge mentale de la femme. La charge médicale correspond à la charge mentale liée à la gestion de la santé du foyer. A travers ce travail, nous souhaitions recueillir les perceptions et expériences des médecins à ce sujet. Nous avons de même analysé les propositions des soignants interrogés pour lutter contre ce déséquilibre. Matériel et méthodes : nous avons mené une étude qualitative par entretiens individuels semi-dirigés auprès de médecins généralistes, pédiatres et gériatres exerçant dans les départements de Gironde et des Pyrénées-Atlantiques. Résultats : 16 médecins ont été interviewés. Tous ont admis reconnaitre l’existence de ce déséquilibre au sein de leur patientèle notamment concernant la gestion de la santé des enfants, des conjoints ou des parents. Les différentes tâches médicales ont été détaillées comme la présence aux rendez-vous médicaux ou le suivi du schéma vaccinal. Selon les médecins, l’origine de ce déséquilibre serait principalement historique et sociétale. Il engendrerait pour les femmes des répercussions sur leur santé mentale et physique, mais aussi sur leur vie professionnelle et familiale. Certains médecins ne se sentent pas légitime d’agir devant cette situation. D’autres se disent non dérangé par ce déséquilibre et considèrent qu’il faut respecter l’organisation de chaque foyer. Enfin des propositions d’inclusion des pères dans la santé de leur enfant ou de conjoint dans leur propre santé ont été amenées. Une sensibilisation et prévention de santé publique autour de ce sujet ont aussi été évoquées, et ce dès l’enfance. Un dépistage par les médecins de l’impact sur la santé de la femme a été recommandé avec une proposition de soutien et d’aide physique et mentale si nécessaire. Discussion : les inégalités dans la réparation de la charge médicale au sein d’un foyer a bien été constatée et détaillée par les médecins interrogés. Des actions de prévention, de sensibilisation et de soutien pourraient être proposées par les médecins et instances de santé aux femmes concernées
BepiColombo cruise science: overview of the mission contribution to heliophysics
No full textInternational audienceBepiColombo, the joint ESA/JAXA mission to Mercury, was launched in October 2018 and is scheduled to arrive at Mercury in November 2026 after an 8-year cruise. Like other planetary missions, its scientific objectives focus mostly on the nominal, orbiting phase of the mission. However, due to the long duration of the cruise phase covering distances between 1.2 and 0.3 AU, the BepiColombo mission has been able to outstandingly contribute to characterise the solar wind and transient events encountered by the spacecraft, as well as planetary environments during the flybys of Earth, Venus, and Mercury, and contribute to the characterisation of the space radiation environment in the inner Solar System and its evolution with solar activity. In this paper, we provide an overview of the cruise observations of BepiColombo, highlighting the most relevant science cases, with the aim of demonstrating the importance of planetary missions to perform cruise observations, to contribute to a broader understanding of Space Weather in the Solar System, and in turn, increase the scientific return of the mission
Nature et montant de l'astreinte
No full textInternational audienceCour de cassation, crim., 1er avril 2025, no 24-80.484, publié au Bulletin ; AJDA 2025. 63
New perspectives for life-design interventions in the anthropocene context
No full textInternational audienceSince 2013, the UNESCO Chair of Lifelong Guidance and Counseling, together with its UNITWIN Network created in 2017, have been driving research, training, and interventions from a Life Design perspective to help people to navigate this uncertain world. This article is a UNESCO Chair position paper which aims to propose a new vision for career counseling in the current context of the Anthropo-Capitalocene. This vision is based on forms of active life, a concept developed in the career guidance literature by Eduard Spranger. This paper identifies new counseling interventions involving a range of activities that make every individual's daily life a certain form of life. The discussion considers avenues for helping individuals to engage in sustainable forms of active life. The conclusion discusses the need to break away from siloed approaches to career counseling and to develop a conception of the individual in connection with the Earth system
Modélisation de l’effet des phénomènes de bypass sédimentaire sur l’évolution moyen à long terme du trait de côte
No full textUnder the effect of wave-induced currents, sand can be transported around natural or artificial rocky obstacles transverse to the beach through a process called sediment bypassing. This phenomenon plays a key role in beach evolution, particularly in embayed beaches, which are delimited by two rocky obstacles and represent half of the world’s beaches. However, sediment bypassing is often neglected or partially included in shoreline evolution models. The aim of this thesis is to extend the applicability of the reduced-complexity model LX-Shore by implementing a parametrization of sediment bypassing. The new version of the model, which integrates the impact of subaqueous bypassing around obstacles, has been tested on an idealised embayed beach subject to various wave incidence conditions. The results show that accounting for bypassing significantly influences embayed beach planform and shoreline spatial variability, in terms of rotation, curvature, and maximum erosion. Applications to real beaches featuring rocky groynes in Denmark and Fréjus (France) or a longitudinal defense structure in Lacanau (France) have provided insights into the influence of bypassing across different timescales: event-scale, annual-scale, and multi-decadal-scale under the effect of sea level rise. By integrating for the first time a generic parametrization of sediment bypassing into a reduced-complexity model, this work contributes to improving the understanding and modeling of shoreline evolution in the presence of rocky obstacles, offering new perspectives for coastal management.Sous l’effet des courants induits par les vagues, le sable peut contourner les obstacles rocheux naturels ou artificiels présents sur la plage via un phénomène nommé bypass sédimentaire. Le bypass joue un rôle clé dans l’évolution des plages, notamment les plages en baie délimitées par deux obstacles rocheux qui représentent environ la moitié des plages dans le monde. Pourtant, ce phénomène est souvent mal pris en compte dans les modèles d’évolution du trait de côte, voire absent. L’objectif de cette thèse est ainsi d’étendre le champ d’application du modèle à complexité réduite LX-Shore en y implémentant une paramétrisation du bypass sédimentaire. La nouvelle version du modèle, intégrant l’impact du bypass subaquatique, est testée sur une plage en baie idéalisée soumise à diverses conditions de vagues d’incidence variable. Les résultats montrent que la prise en compte du bypass impacte significativement la forme moyenne de la plage et la variabilité spatiale du trait de côte, notamment en termes de rotation, courbure et maximum d’érosion. Des applications sur des plages réelles présentant des épis rocheux (au Danemark et à Fréjus) ou un ouvrage de défense longitudinal (Lacanau) ont permis d’explorer l’influence du bypass à différentes échelles de temps : à l’échelle évènementielle, à l’échelle annuelle et à l’échelle pluri-décennale, sous l’effet de l’élévation du niveau marin. En intégrant pour la première fois une paramétrisation générique du bypass sédimentaire dans un modèle à complexité réduite, ces travaux contribuent à améliorer la compréhension et la modélisation de l’évolution du trait de côte en présence d’obstacles rocheux, offrant ainsi de nouvelles perspectives en termes de gestion des zones côtières