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A Fluvio‐Lacustrine Environment Preserved in the Jezero Crater Inlet Channel, Neretva Vallis, Mars
No full textInternational audienceMartian fluvial valleys provide evidence for the surface flow of liquid water, making them a key target for rover-based investigations of ancient habitability. The Mars 2020 Perseverance rover spent ∼85 sols exploring the Bright Angel formation, exposed across the floor of Neretva Vallis: the western inlet channel of Jezero crater. This study documents the sedimentology and stratigraphy of the Bright Angel formation to reconstruct its depositional setting. The unit preserves a concave-up bedding structure consistent with a young channel-fill deposit, rather than an older unit exposed by incision of Neretva Vallis. The lower stratigraphy displays a fining-up sequence from coarse-grained sediments up to pebble-conglomerates (the Tuff Cliff member) into a ≥10-m-thick succession of laminated mudstone (the Walhalla Glades member), interpreted as a transgressive sequence recording the onset of lacustrine conditions in Neretva Vallis. Lenses of matrix-supported granule-conglomerate adjacent to the valley wall (the Fern Glen Rapids member) may preserve locally derived debris flows entering the lake. These are overlain by a polymict, matrix-supported, boulder-conglomerate (the Mount Spoonhead member), interpreted as a high-energy debrite derived from the watershed. The sequence is capped by cross-stratified sediments (the Serpentine Rapids member), preserving lake margin deposits. The Bright Angel lacustrine sequence occurs ∼10–50 m higher in elevation than the lake level anticipated for the Jezero western delta, requiring an additional period of lacustrine activity. The structure and spatial distribution of the unit leads us to propose that a late-stage blockage of Neretva Vallis may have facilitated the formation of a perched, valley-confined lake upstream
Comparison of two exergame-based motor-cognitive trainings: protocol for a pilot study on cognitive, motor, and psychiatric symptoms in patients with huntington’s disease (CARE-MH)
No full textInternational audienceBackground: Huntington’s disease (HD) is a rare, hereditary neurodegenerative disorder. Symptoms manifest around the age of 40 and encompass a range of physical, cognitive, and psychiatric impairments. Motor and cognitive exercises have been shown to slow the progression of symptoms. Particular attention has been given to motor-cognitive training, which may combine the benefits and contribute to delaying the progression of the disease. However, studies investigating the efficacy of such training in HD remain limited. At the same time, the use of exergaming has shown promise in improving participant engagement in training, which may in turn enhance both physical and cognitive functioning. The aim of our pilot study is to evaluate the feasibility and effects of two home-based motor-cognitive trainings via an exergame on motor, cognitive, and psychiatric symptomatology in HD patients. Methods: Patients, from stages 1 and 2, will be randomly assigned to one of the two groups: sequential exercises (separate motor and cognitive exercises) or synergical exercises (simultaneous motor and cognitive exercises). Training sessions will be conducted individually over a 12-week period (3 sessions/week ; 60 minutes/session). Linear mixed-effects models will be used to assess training’s effects on balance, walking capacity, lower-extremity strength, disease-related motor impairments, global cognition, executive functions, depression, anxiety, disease-specific psychiatric symptoms, and quality of life. Discussion: Our pilot study will be the first one to compare two exergame-based motor-cognitive trainings in HD patients. It is expected to be feasible, with improvements in motor, cognitive, and psychiatric symptoms in both groups. However, greater improvements are expected in the synergical group compared to the sequential group
Effect of high-dose baclofen on post-traumatic stress disorder symptoms five years after hospitalization among critically ill patients with unhealthy alcohol use
No full textInternational audienc
The new ethical challenges raised by the authorization of elective egg freezing in France since 2021
No full textInternational audiencePurpose: Since 2021, elective egg freezing (EEF) without medical indication has been authorized and fully reimbursed in France for women aged 29 to 37. While this regulatory change represents a significant advancement in reproductive rights, it also raises new ethical and organizational challenges. This study aimed to explore the ethical issues experienced by infertility specialists involved in the clinical implementation of EEF in France.Methods: This prospective, qualitative, monocentric study was conducted in a university-based ART center. All physicians involved in EEF at the center were invited to participate in semi-structured interviews. Data were analyzed inductively using Grounded Theory methodology.Results: Eight practitioners participated. Four main themes emerged: (1) challenges in accessing EEF due to resource constraints and growing demand; (2) a new relationship between caregiver and patient in a context where care is no longer strictly medical; (3) a need to redefine the role of EEF in society, including the terminology used and funding mechanisms; and (4) questions about the future of EEF, including prioritization criteria, equitable access, and sustainability of the current model.Conclusions: While EEF is widely supported by healthcare professionals, its integration into routine practice reveals tensions between autonomy, justice, beneficence, and public resource management. National guidelines, improved access to information, and further research-particularly incorporating women's perspectives-are essential to ensure ethically sound implementation
Extreme macroeconomic risk, personal expectations and financial decisions: an information experiment on five European countries
No full textFollowing the Covid-19 crisis, extreme macroeconomic risks in terms of both GDP and inflation have returned to the spotlight in Europe. Against this backdrop, we conducted a large-scale online survey experiment in five large European countries (France, Germany, Italy, Spain and the UK) to measure household expectations of future extreme macroeconomic risks and their transmission to personal expectations and planned financial decisions. Exploiting both a between and within-subject design, we provided half of the participants with information about past extreme macroeconomic events in Europe. Our findings indicate that European households have high expectations of future tail macroeconomic events shaped by personal experiences, and that the causal effect of information provision on expectations varies greatly depending on the country and the type of risk. We then find suggestive evidence that expectations of extreme macroeconomic disasters are causally transmitted to personal expectations about one's future standard of living. However, small variations in expectations of extreme macroeconomic risk do not appear to have a systematic independent impact on planned saving, portfolio, and borrowing decisions
Dire l'aidance dans le cas de la maladie d'Alzheimer : du dit, du suggéré à l’impensé,
No full textInternational audience« Je ne suis pas son aidante, je suis sa femme ». Malgré une visibilité grandissante de l’aidance dans l’espace public se dire « aidant » reste compliqué. Le mot véhicule des représentations sociales empreintes de valeurs contradictoires. Dans le contexte de la maladie d’Alzheimer, il s’inscrit en plus dans un impensé culturel : celui de vivre avec une maladie qui efface progressivement l’histoire sur laquelle s’est construit le lien affectif et pourtant d’accepter le rôle d’aidant en vertu de ce lien. Le choix d’aborder l’aidance par les discours, par une analyse des mots et formulations langagières, permet de comprendre comment ces discours (re)construisent une identité dans et à travers l’aidance. Nous identifions ainsi des pratiques plus ou moins opérationnelles, des savoirs progressivement construits, mais aussi des résistances – matérielles ou subjectives – auxquelles les aidants se heurtent pour assumer les tâches nécessaires, sans négliger les sources de satisfaction ou d’insatisfaction qu’ils trouvent dans la relation d’aide. L’ouvrage, inscrit en sciences du langage, apporte un point de vue complémentaire à celui des sciences humaines et sociales sur un maillon essentiel de la chaine de soin mais encore mal connu et reconnu
Revealing the role of functional binder PEDOT:PSSTFSI in cathode-electrolyte interphase formation on LiFe<sub>0.4</sub>Mn<sub>0.6</sub>PO<sub>4</sub> electrodes of Li-ion battery
No full textInternational audienceThe stability of the cathode–electrolyte interphase (CEI) plays a critical role in determining the long-term performance of Li-ion batteries, particularly under high-voltage operation. This work investigates CEI formation and evolution in LiFe0.4Mn0.6PO4 (LFMP) composite positive electrodes using PEDOT:PSSTFSI, a conductive polymer that replaces both carbon black and polyvinylidene fluoride (PVDF) binder in the electrode formulation. Electrochemical tests, XRD, and XPS confirm PEDOT:PSSTFSI's electrochemical stability up to 4.5 V vs. Li+/Li and non-reactivity towards the active material. Reversible redox activity is observed in XPS, but it does not affect long-term structural or electrochemical stability. XPS analysis of C 1s, O 1s, P 2p, and F 1s spectra across different charge states reveals that PEDOT:PSSTFSI promotes a thinner, more stable CEI without altering its composition compared to carbon-containing references. This reduced interfacial degradation corresponds with improved performance at higher voltages during extended cycling. The results underscore PEDOT:PSSTFSI's promise as a multifunctional binder offering conductivity, stability, and interfacial control for advanced Li-ion positive electrodes.</p
AI-enabled evolution: unveiling the synergy between manufacturing and services through coordination and integration
No full textInternational audienceCoordination and integration are fundamental pillars of modern supply chains, within which manufacturing and service operations function as two core components. Recently, the growing availability of data, coupled with rapid advances in artificial intelligence (AI), has significantly accelerated the adoption of AI technologies across manufacturing and service domains. Against this backdrop, we completed a special issue titled “AI-Enabled Evolution: Unveiling the Synergy between Manufacturing and Services through Coordination and Integration” to showcase the latest developments in this domain. In this editorial, we first outline the background and review existing literature on AI applications in operations management. We then present the papers included in this issue, highlighting how various AI techniques are applied across manufacturing and service contexts, encompassing performance improvement and sustainability advancement, optimisation and decision-making framework development, as well as applications in logistics, scheduling, and risk management. Finally, we conclude by identifying promising avenues for future research
Determination of Venus’s Rotation State Using Radio-tracking Data from the Venus Express Spacecraft
No full textInternational audienceDespite its similarities to Earth, our understanding of Venus remains limited, particularly regarding its long retrograde rotation period. This has been measured using both Earth-based and in-orbit methods. However, the values obtained exhibit significant variations that cannot be explained by models of various physical mechanisms that could affect the rotation period of Venus. In this study, we present a new determination of the rotation period of Venus based on the precise orbit determination method applied to the radio-tracking data of the Venus Express (VEX) spacecraft. This method consists of a least-squares adjustment of the difference between Doppler data collected by ground-based stations and simulated Doppler data from a force model governing the spacecraft's motion. We find a rotation period of 243.02064 ± 0.0010 days, which is consistent with results from studies using tracking data from previous orbiters, and with Earth-based radar techniques for the same period covered by the VEX tracking dataset. An attempt was also made to adjust other parameters, including the precession rate, the gravitational field, and the Love number k2 . Nevertheless, no reliable results for these parameters could be obtained due to the lack of tracking data in the low altitude part of the highly eccentric orbit of VEX. The upcoming Venus missions, such as VERITAS (NASA) and EnVision (ESA) are expected to provide accurate Doppler tracking measurements that will improve our understanding of the planet
Integrating ethical, societal and environmental issues into algorithm design courses
No full textThis document, intended for computer science teachers, describes a case study that puts into practice a questioning of ethical, societal and environmental issues when designing or implementing a decision support system. This study is based on a very popular application, namely road navigation software that informs users of real-time traffic conditions and suggests routes between a starting point and a destination, taking these conditions into account (such as Waze). The approach proposes to intertwine technical considerations (optimal path algorithms, data needed for location, etc.) with a broader view of the ethical, environmental and societal issues raised by the tools studied. Based on the authors' experience conducting sessions with students over several years, this document discusses the context of such a study, suggests teaching resources for implementing it, describes ways to structure discussions, and shares scenarios in different teaching contexts