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Oyster shells as archives of present and past environmental variability and life history traits: A multi‐disciplinary review of sclerochronology methods and applications
No full textInternational audienceOysters inhabit a variety of coastal and deep‐sea settings over a wide latitudinal range and have a role as ecosystem engineers. They also represent an important food source for humans since hunter‐gatherer times, which motivates interest in using oyster shells as environmental and life history archives. Still, oysters have often been disregarded in sclerochronology studies, although several methods based on both microtextural and geochemical approaches have successfully been investigated. We review how these methods have been used to improve interpretations of shell records, and we identify knowledge gaps in a variety of disciplines. Those include ecology to study larval dispersal and growth rates; archaeology to determine shell midden constructions and site occupations; and palaeoenvironmental and palaeoclimate reconstructions from tidal to annual timescales. We also suggest standardizing sclerochronology procedures to improve palaeoenvironmental reconstructions and biophysical models on oyster larval dispersal
Assessment of the sedimentation and trapping efficiency in dam reservoirs by applying the settling basin framework
No full textInternational audienceStudy region: The investigated object is the Lobo Dam reservoir, located in the south part of the Lobo River Basin in west-central Côte d’Ivoire, West Africa.Study focus: Dam reservoirs in tropical climates face rapid siltation and eutrophication challenges, necessitating new analytical solutions to understand their capacity to trap sediment inputs. This study presents a hydrosedimentary mathematical model based on the theory of settling basins and Gamma Law approaches to describe the settling velocity of suspended solids. Using field data from the Lobo River reservoir in Côte d′Ivoire.New hydrological insights for the region: The analysis shows that the reservoir’s trapping capacity is influenced by settling velocity, critical velocity, shape parameter 1/r, and the Peclet number (Pe). The study found strong synchronization between models for constant settling velocity (CV-NT, CV-CM, CV-Teeter (1986)) and variable settling velocity (VV-NT, VV-CM) with Teeter’s (1986) model. This agreement validates the proposed models. However, for Pe>4, the numerical values and curves fall outside the validity range of Teeter’s (1986) model, particularly during dry periods. The findings provide crucial insights into the hydrosedimentary dynamics of the Lobo River reservoir, emphasizing the need to account for seasonal variations and hydrological conditions. This research offers valuable guidance for sediment and water resource management, contributing to the sustainability of reservoirs in tropical regions facing similar environmental pressures
Evolution of CYP71D drives the diversification of monoterpene indole alkaloid biosynthesis in Gentianales
No full textInternational audienc
Climate Change and Respiratory Health: Opportunities to Contribute to Environmental Justice: An Official American Thoracic Society Workshop Report
No full textInternational audienceAdverse environmental exposures worsened by our changing climate threaten respiratory health and exacerbate existing social inequities that further undermine environmental justice (EJ). EJ is the capacity of all people, regardless of sociodemographic characteristics, to minimize harmful exposures and live a healthy life. EJ is achieved through the development, implementation, and enforcement of environmental laws, regulations, and policies. In 2023, an American Thoracic Society workshop convened a group of 39 clinicians, researchers, community advocates, research program administrators, and health policy experts to characterize the respiratory health threats and EJ concerns arising from climate change. The workshop explored four main climate areas through a socioecological and EJ perspective: 1) respiratory health risks, 2) respiratory health impacts in low- and middle-income countries, 3) climate mitigation and adaptation strategies, and 4) priority research infrastructure needs. The workshop committee concluded that climate change can directly and indirectly impair respiratory health and that persistently excluded or marginalized communities (including those in low- and middle-income countries) are disproportionately impacted. These disproportionately impacted communities also lack hazard monitoring and resources to evaluate and advocate for mitigation of adverse environmental exposures. Future respiratory health research must inform mitigation strategies to reduce climate-related emissions from industry to net zero. Researchers, communities, and policymakers require training and support to meaningfully engage with systems-thinking research as well as policy solutions focused on mitigating and adapting to climate change. Finally, the workshop committee recommends a rapid transition away from fossil fuel dependence to a world that provides an equitable allocation of clean transportation options and renewable sources of energy production
Diversité des stratégies opératoires en situation réelle et en environnement virtuel
No full textNational audienceThis article focuses on the analysis of the diversity of operational strategies, both in real working conditions and within simulated environments. Examining this diversity provides valuable insights into the mechanisms of activity regulation, thereby contributing to the optimization of approaches for the prevention of Musculoskeletal Disorders (MSDs). Our study seeks to determine whether the use of virtual simulation, integrated into a Serious Game, enables users to establish favorable conditions for efficient regulation of their future professional activities. After demonstrating the inter-individual diversity of operational strategies for similar tasks in industrial settings (automotive and watchmaking sectors), we aim to explore how this diversity is manifested in similar activities simulated within a virtual reality Serious Game. The main findings reveal the presence of multiple operational strategies for each simulated task, which appear to reflect conditions conducive to improved activity regulation.Cet article se focalise sur l’analyse de la diversité des stratégies opératoires, à la fois en conditions réelles de travail et au sein d’environnements simulés. L’analyse de la diversité des stratégies opératoires pourrait apporter des perspectives précieuses sur des mécanismes de régulation de l’activité, participant ainsi à optimiser les démarches de prévention des troubles musculosquelettiques (TMS). Notre étude vise à déterminer si l’usage de la simulation virtuelle, intégrée dans un Serious Game, permet aux utilisateurs de mettre en place les conditions propices à une régulation efficiente de leurs futures activités professionnelles. Après avoir démontré la diversité interindividuelle des stratégies opératoires pour des tâches similaires dans le milieu industriel (de l’automobile et de l’horlogerie), nous souhaitons examiner comment cette diversité se manifeste dans des activités similaires simulées dans le cadre d’un Serious Game en réalité virtuelle. Les principaux résultats montrent la présence, pour chaque tâche simulée, de plusieurs stratégies opératoires qui semblent refléter des conditions favorables à une régulation des activités
Kadomtsev-Petviashvili hierarchies with non-formal pseudo-differential operators, non-formal solutions, and a Yang-Mills–like formulation
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Genome editing, an opportunity to revive soybean cultivation in Europe
No full textInternational audienceSoybean ( Glycine max Merr.) is the world's most important oilseed crop and its ability to fix atmospheric nitrogen makes it a cornerstone of sustainable agriculture. Despite its importance, Europe relies heavily on imports, leading to environmental and economic vulnerabilities. To address these challenges, the European Union has implemented policies to boost local soybean production, emphasizing sustainable practices and reduced dependency on imports. However, conventional breeding methods are time‐consuming and may not keep pace with the rapid environmental and consumer habit changes. Genome‐editing technologies, such as CRISPR‐Cas, offer precise and efficient tools for developing soybean varieties tailored to European conditions. These technologies can enhance traits related to precocity, stress responses, yield and quality that are essential for adapting to climate change and promoting ecological sustainability. This review explores the integration of genome editing (GE) in soybean breeding, highlighting its potential in advancing the agroecological transition in Europe. By having a clear regulation and enhancing breeding efforts, GE can significantly contribute to developing resilient and sustainable soybean varieties, fostering a competitive and environmentally friendly European agriculture
Addressing Akrasia in Childhood, Adolescent and Young Adult Cancer Survivors: Implications for Long-Term Follow-Up and Preventive Health Interventions
No full textInternational audienceBackground: Childhood, adolescent, and young adult cancer survivors (CAYACS) face significant long-term health risks, yet adherence to long-term follow-up (LTFU) care remains inconsistent. This study explores the concept of akrasia (i.e., acting against one’s better judgment by engaging in behaviors known to be harmful or counterproductive) to understand the psychological, cognitive, and systemic barriers influencing survivor engagement in LTFU. Method: Using an ethical reflection approach based on a literature review, we discussed survivor experiences, behavioral science insights, and ethical principles to identify solutions that balance patient autonomy with supportive interventions. A narrative approach was used to summarize the key points discussed during the ethics reflection group meetings. Results: Our findings highlight key barriers such as trauma, avoidance behaviors, and cognitive constraints that contribute to non-adherence. Strategies such as shared decision-making, digital health tools, and nudge-based interventions are proposed to enhance survivor engagement. Ethical considerations emphasize the need for personalized and flexible care approaches that respect survivor agency while mitigating obstacles to adherence. Conclusions: Addressing akrasia through ethical and behavioral frameworks could improve LTFU adherence, ultimately enhancing survivorship care and long-term health outcomes
A global survey for dust devil vortices on mars using MRO context camera images enabled by neural networks
No full textInternational audienceDust devils are atmospheric vortices that loft dust from the ground, typically at the hottest times of the day and year on Mars. They contribute dust to the atmosphere and so indirectly affect the global atmospheric circulation. Their size, shape and velocity can provide indications of the weather on Mars. Hence, tracking their occurrence in time and space provides useful data for understanding Mars' current climate. They are also of relevance to landed missions as they can clean solar panel surfaces, extending mission lifetimes. Despite the numerous observations and surveys of dust devils to date, the global extent, distribution and occurrence of dust devils is not yet consistently constrained, mainly due to the relatively limited spatial and temporal scope of manual analyses. To provide the most comprehensive global catalogue of active martian dust devils to date, we applied a Reti-naNet convolutional neural network to existing remote sensing images of Mars to identify the distinctive signature of the light-toned lofted dust cloud and dark shadow formed by active dust devils on Mars. The algorithm used ~6 m/pixel Context Camera (CTX) images from Mars Years 28-36, scanning through a total of 132 359 images. False positives were manually removed with the help of the Zooniverse platform, resulting in 13 409 detections. This survey presents the most spatially and temporally exhaustive global catalogue of dust devils to date. We confirm many trends revealed in disparate previous studies. For example, approximately half of the detections are concentrated in the Amazonis Planitia monitoring sitea hotspot identified from previous imaging campaigns. In addition, we confirm that orbital observations are not well-suited for detecting dust devils at landing sites, despite the ubiquitous detection of vortices with in-situ data. Our study reveals previously understudied hotspots where dust devil lofted clouds can be seen from orbit, most notably southern Hellas Planitia where only dust devil tracks had been previously extensively reported. Importantly, our results reveal latitudinal clusters of dust devils, and in particular large dust devils, at around 60 • N and 60 • S during local summer solstice, which had only been hinted at by previous work. This concentration is at a much higher latitude than previous modelling suggests, indicating that dust devil generation on Mars is controlled by more factors than are currently accounted for