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Identifying zooplankton fecal pellets from in situ images
No full textInternational audienceZooplankton play a crucial role in the biological carbon pump by producing sinking particles including sloppy feeding by-products, fecal pellets, molts and carcasses. However, quantifying their impact of these particles on the carbon cycle remains difficult. The contribution of fecal pellets to particulate organic carbon export is usually assessed using fecal pellets collected from sediment traps and laboratory studies. Here, we identified 50 771 fecal pellet-like particles distributed across three morphological clusters. These were extracted from 987 236 in situ images of non-living particles collected from Baffin Bay (Arctic Ocean) using the Underwater Vision Profiler (UVP). We associated which taxonomic groups produced the fecal pellets by comparing the UVP images with observations of fecal pellet morphology and length. Our results emphasize the feasibility of quantifying fecal pellets from in situ images and the importance of developing the resolution of imaging tools that would simultaneously identify smaller fecal pellet-like particles and capture images of large crustacean zooplankton. Using in situ images in identifying fecal pellets will facilitate a better understanding of their dynamics, a more accurate calculation of carbon fluxes, and the representation of fecal pellets in biogeochemical models
Deep-water limit of the intermediate long wave equation in
No full textInternational audienceWe study the well-posedness issue of the intermediate long wave equation (ILW) on both the real line and the circle. By applying the gauge transform for the Benjamin-Ono equation (BO) and adapting the well-posedness argument for BO by Molinet and the fourth author (2012), we prove global well-posedness of ILW in on both the real line and the circle. In the periodic setting, this provides the first low regularity well-posedness of ILW. We then establish convergence of the ILW dynamics to the BO dynamics in the deep-water limit at the -level
Intense and localized export of selected marine snow types at eddy edges in the South Atlantic Ocean
No full textInternational audienceAbstract. The biological carbon pump (BCP) comprises a wide variety of processes involved in transferring organic carbon from the surface to the deep ocean. This results in long-term carbon sequestration. Without the BCP, atmospheric CO2 concentrations would be around 200 ppm higher. This study reveals that ocean dynamics at the mesoscale and submesoscale could have a major impact on particulate organic matter (POM) vertical distribution. Our results indicate that intense submesoscale frontal regions, such as those between mesoscale eddies, could lead to an important accumulation and transport of POM from the mixed-layer depth (MLD) down to the mesopelagic zone. To reach these conclusions, a multifaceted approach was applied. It included in situ measurements and marine snow images from a BGC-Argo float equipped with an Underwater Vision Profiler (UVP6), satellite altimetry data, and Lagrangian diagnostics. We focused our study on three intense features in marine snow distribution, observed during the 17-month-long float mission in the Cape Basin in the southwest of Africa. These features were located in the frontal region between mesoscale eddies. Our study suggests that a particle injection pump induced by a frontogenesis-driven mechanism has the potential to enhance the effectiveness of the biological pump by increasing the depth at which carbon is injected into the water column. This work also emphasizes the importance of establishing repeated sampling campaigns targeting the interface zones between eddies. This could improve our understanding of the mechanisms involved in the deep accumulation of marine snow observed at eddy interfaces
Early Classification of Human Motion Intent for Exoskeleton Assistance Using Kinematics
No full textExoskeletons can reduce physical effort and the risk of work-related musculoskeletal disorders by providing robotic assistance in repetitive tasks. Designing exoskeletons that seamlessly assist human users without disrupting their natural movements poses a significant challenge, necessitating accurate prediction and adaptation to their motion intent. Particularly, an erroneous detection of motion intent could result in large adversarial effects where the exoskeleton resists the user's desired movement. We propose to analyze the possibility of early and accurate intent detection using only kinematic information and quantify the disturbance that a failed intention detection could entail. We evaluate different classification methods with voluntarily ambiguous experimental data on the intention underlying reaching movements towards four targets in a parasagittal plane. We show that, while recent advances in time series classification -namely using a convolutional and residual neural network-can enable earlier and more accurate intent detection, an informed adaptation of the assistance according to the classification's confidence level is necessary
Prevalence of psychiatric disorders during pregnancy—a feasibility study at second trimester ultrasound in the general population (GROUP study): study protocol
No full textInternational audienceIntroduction: During the perinatal period, women have an increased risk for psychiatric disorders, which are highly prevalent in this context. In addition, there are significant delays in diagnosing these conditions, worsening their prognosis and increasing their societal burden. Studies describing psychiatric disorders in the perinatal period often focus on specific disorders; only postpartum depression and, to a lesser extent, anxiety disorders are studied. There are also very few evaluations conducted by clinicians based on a semistructured interview, relying on the diagnostic criteria of international nosography.Methods and analysis: This multicentric prospective study will recruit 140 adult pregnant women based on randomly selected second trimester (T2) ultrasound consultations. The primary outcome is the prevalence of any psychiatric disorder assessed with a standardised psychiatric assessment, the Mini-International Neuropsychiatric Interview (M.I.N.I.). Within 10 days after the T2 ultrasound appointment, we will conduct the M.I.N.I., collect demographic data, evaluate suicidal behaviour with the Columbia-Suicide Severity Rating Scale, describe negative life events from the past year using the Paykel questionnaire and evaluation of social deprivation (Evaluation of the Deprivation and Inequalities of Health in Healthcare Centres score). Participants will also complete self-administered psychiatric questionnaires that screen for specific pathologies. We will build a biological sample collection. At two months post partum, we will repeat the questionnaires, adding an assessment of mother-child bonding. Patients can choose between in-person or telemedicine visits on both occasions.Ethics and dissemination: All participants will be required to provide written informed consent. The study has received ethical approval from the French National Committee ('Comité de Protection des Personnes Ouest VI') (approval number: 23.03919.000236). Results will be disseminated through peer-reviewed journal publications and at scientific conferences and meetings.Trial registration number: NCT0629725
La conservation de l'Etat en droit international
No full textInternational audienceState "self-preservation" is traditionally associated with a theory developed between the 18th and 20th centuries, known as the "the fundamental rights of states doctrine". According to this doctrine, just as individuals enjoy a right to life, states should possess a "right of self-preservation" enabling them to preserve their existence. While taking this doctrine as a starting point for analysis, the thesis makes a few adjustments in the light of recent state practice. States invoke a "right of self-preservation" in two ways: firstly, in order to justify the exercise of rights that they describe as inherent to their sovereignty; secondly, by mobilizing "self-preservation" not as a mere "right", but as a structuring principle of international law. Thus, states intend to demonstrate that all rules of international law presuppose the preservation of their existence, and that this consideration plays a role in the entire normative process: i.e. the creation, application and contestation of legal rules. The aim of this thesis is to determine how claims relating to the preservation of the state are received by international law, whether or not they are admitted, and what this reveals about the subject. In reality, state preservation exerts a hold on international law, notably by structuring its principal rules. But, in return, international law also exerts a hold on state conservation, by imposing limits on a potentially arbitrary conduct.La « сonservation de soi de l'Etat » a été théorisée entre le XVIIIe et le XXe siècle dans le cadre de la doctrine des droits fondamentaux des Etats. Selon cette doctrine, de la même manière que les êtres humains bénéficient d'un droit à la vie, les Etats devraient posséder un « droit de conservation de soi » leur permettant de préserver leur existence. Tout en prenant cette théorie comme point de départ de l'analyse, l'objet de la recherche est de l'ajuster à la lumière de la pratique récente. Ainsi, les Etats invoquent un « droit de conservation de soi » de deux façons : soit pour justifier l'exercice de droits qu'ils qualifient d'inhérents à leur souveraineté et présentés, donc, comme existentiels, soit pour mobiliser la « conservation de soi » non plus comme un simple « droit », mais comme un principe structurant du droit international. En d'autres termes, les Etats entendent démontrer que la plupart des règles de droit international supposent ou impliquent la préservation de leur existence. Cette considération intervient sur l'ensemble du processus normatif : i.e. sur la création, l'application et la contestation des règles juridiques. L'enjeu de la thèse consiste à déterminer de quelle façon les prétentions liées à la conservation de l'Etat sont reçues par le droit international et ce que cela révèle du sujet. On se rend compte que la conservation de l'Etat exerce une emprise sur le droit international, notamment en structurant ses principales règles. Mais, en retour, on doit constater symétriquement que le droit international exerce une certaine emprise sur la conservation de l'Etat en imposant des limites à une conduite potentiellement arbitraire
Pour une science de la Transition Énergétique au Service de la Société: Rapport du groupe interdisciplinaire ARPEGES CNRS pour la Transition énergétique
No full textNational audienceResearch on the energy transition raises a series of major challenges: it is a problem-oriented field of research (that of decarbonising the energy mix), which must be resolutely ethical and include principles of social and environmental justice from the very beginning... and this despite the problematic nature of the notion of transition which gives a misleading notion of the process that will lead to desired changes - if there are any. Taking this observation as its starting point, this paper sets out a number of avenues for research into key issues. It begins by examining the way in which the energy transition is transforming the interplay between actors in the energy sector and the scales at which decisions are taken and implemented. While inviting to take account of the wide variety of national contexts and levels of development, the article acknowledges the certainties and uncertainties surrounding the composition of the energy mix. It also stresses the importance of taking account of the externalities of technological choices, particularly in environmental terms. This enables us to draw up a research agenda focusing not only on the spatial aspects of transitions, but also on the ways in which economic models need to incorporate new parameters and new constraints. The article also invites to consider how the relationship between energy production and consumption is changing, and how consumption needs to be reduced. In so doing, the article defends the idea that research, which is necessarily interdisciplinary and reflexive, has a strong role to play in basing transition action on scientifically sound findings.La recherche sur la transition énergétique pose plusieurs défis de taille : c’est une recherche orientée problème (celui de la décarbonation du mix énergétique), qui doit être résolument éthique et intégrer dès sa formulation des principes de justice sociale et environnementale... et ce alors même que la notion de transition est problématique en ceci qu’elle donne une fausse idée du processus qui mènera aux changements attendus – si changements il y a. Partant de ce constat, ce Regard dresse des pistes de recherche sur des thématiques saillantes, notamment sur les acteurs et échelles des transitions, les techniques et leurs externalités, les modèles économiques et sociaux qui permettent de guider l’action, les modèles de consommation production et s’interroge sur les rapports entre consommation et production. Il défend in fine l’idée que la recherche, forcément interdisciplinaire et réflexive, a un rôle fort à jouer pour fonder l’action en matière de transition sur des constats scientifiquement fondés
Hysteresis of the Antarctic Ice Sheet With a Coupled Climate-Ice-Sheet Model
No full textInternational audienceThe stability of the Antarctic ice sheet under different fixed CO 2 levels and orbital configurations is explored using a coupled climate-ice sheet model, starting from either a pre-industrial ice sheet or an ice-free, isostatically rebounded geometry. Simulations reveal a strong hysteresis effect: equilibrium ice volumes differ significantly for equivalent CO 2 levels, depending on the initial ice sheet geometry. Crucially, the albedo-melt feedback is accounted for in our coupled setting, resulting in a nonlinear response of the ice sheet to the CO 2 forcing. Critical CO 2 thresholds trigger either the complete Antarctic ice sheet loss or near-complete regrowth. The orbital configuration influences these CO 2 thresholds. These findings highlight the importance of ice sheetatmosphere interactions, notably the albedo-melt feedback, in projecting future long-term ice sheet behavior. Neglecting these feedbacks could lead to an overestimation of CO 2 thresholds for ice sheet destabilization, with implications for future long-term sea level rise under high emission scenarios.</div
« Actualité des territoires non-autonomes : la quatrième décennie internationale de l’élimination du colonialisme sera-t-elle la dernière ? », Annuaire français de droit international, LXIX 2023, pp. 105-120
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L’Éducation à l’ESS en France
No full textLe groupe de travail ESCAP "enseigner l'économie sociale en secondaire" est piloté par la chaire économie sociale de l'université de Louvain. https://escap.be/gt-escap/ d’envisager comment insérer la thématique et les outils de l’économie sociale et de la transition socio-écologique dans les programmes de cours du secondaire, d’analyser comment former les futur-es enseignant-es du secondaire à des outils qui intègrent la transition socio-écologique, la créativité, l’utilisation des récits en lien avec l’ES. d’envisager comment insérer la thématique et les outils de l’économie sociale et de la transition socio-écologique dans les programmes de cours du secondaire, d’analyser comment former les futur-es enseignant-es du secondaire à des outils qui intègrent la transition socio-écologique, la créativité, l’utilisation des récits en lien avec l’ES.International audienceUne présentation réalisée dans le cadre du groupe de travail ESCAP, donnant quelques éléments autour de l'éducation à l'ESS en France