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Behavioral and Physiological Stress Reactions During Exposure to a Tsunami in Virtual Reality
No full textInternational audienceIntroduction The simultaneous study of physiological stress and behavioural reactions in individuals evacuating during a disaster situation is rarely conducted. Virtual reality (VR) offers an ecological way to study this phenomenon. Objectives We investigated stress and behavioural responses, as well as the influence of others behaviour, in individuals exposed to a tsunamitype natural disaster simulated in VR. Methods Eighty-eight participants (43 women, 45 men, mean age: 26.8, SD = 9.4) took part in the experiment. Three experimental conditions were defined to study emotional contagion: being alone on the beach; being in the presence of calm virtual agents; or being in the presence of “panicked” ones (random assignment). The sense of presence in the virtual environment was assessed using validated scale to evaluate the effectiveness of the VR system. Emotional/Stress response were measured using physiological indicators (heart rate, electrodermal conductance) collected repeatedly over throughout the scenario. Escape behaviour was assessed by measuring movement speed in the virtual environment. Results The mean presence score was 3.32 out of 6 (SD = 0.90). Random effects mixed models for longitudinal data showed an increase in movement speed as soon as the wave appeared, followed by an increase in stress when the alarm was triggered (electrodermal conductance and heart rate), with no significant differences between conditions with or without virtual agents. Conclusion The results suggest a rational, moderate reaction to danger. Combined with the absence of emotional panic contagion, these findings challenge the widespread media portrayal of disaster victims as reacting with irrational panic.</p
L'invention de la Coutume de Bretagne: Essai sur la construction de la règle coutumière dans une principauté médiévale (v. 1180 – v. 1580)
No full textFor several years now, many studies have been renewed our understanding of customary law. At the same time, the institutional and political history of the Duchy of Brittany has benefited from the work of medievalists. However, the question of the formation of Breton customary law remains largely unknown and dependent on old works. With the exception of the work of Marcel Planiol, a French jurist and legal historian who died in 1931, and a few scattered studies, medieval Breton law has benefited neither from the historiographical revival relating to customary law, nor from that at work among Breton medievalists. This thesis looks at the formation of the Coutume de Bretagne, both from the point of view of a territorial jurisdiction and from that of a body of specific rules. Drawing on recent historical research, the aim is to reconstruct the formation of Breton customary law from a long-term perspective, by analysing the ways in which justice was exercised and, in particular, the Breton « notaries » of the period.Depuis plusieurs années, de nombreuses études sont venues renouveler notre compréhension du phénomène coutumier. Dans le même temps, l’histoire institutionnelle et politique du duché de Bretagne a bénéficié des travaux des médiévistes. Toutefois, la question de la formation du droit coutumier breton demeure largement méconnue et tributaire d’ouvrages anciens. A l'exception des travaux de Marcel Planiol, juriste français et historien du droit mort en 1931, et de quelques études dispersées, le droit breton médiéval n'a bénéficié, ni du renouveau historiographique relatif au droit coutumier, ni de celui à l’œuvre chez les médiévistes bretons. Cette thèse s’intéresse à la formation de la Coutume de Bretagne, tant sous l’angle d’un ressort territorial que sous celui d’un corps de règles spécifiques. À partir des apports de la recherche historique récente, elle se propose, dans une perspective de longue durée, de restituer la formation du texte coutumier breton par une analyse des cadres d'exercice de la justice et notamment, du ''notariat'' breton de cette époque
Material characterization methods for investigating charge storage processes in 2D and layered materials-based batteries and supercapacitors
No full textInternational audienceTwo-dimensional (2D) materials offer distinct advantages for electrochemical energy storage (EES) compared to bulk materials, including a high surface-to-volume ratio, tunable interlayer spacing, and excellent in-plane conductivity, making them highly attractive for applications in batteries and supercapacitors. Gaining a fundamental understanding of the energy storage processes in 2D material-based EES devices is essential for optimizing their chemical composition, surface chemistry, morphology, and interlayer structure to enhance ion transport, promote redox reactions, suppress side reactions, and ultimately improve overall performance. This review provides a comprehensive overview of the characterization techniques employed to probe charge storage mechanisms in 2D and thin-layered material-based EES systems, covering optical spectroscopy, imaging techniques, X-ray and neutron-based methods, mechanical probing, and nuclear magnetic resonance spectroscopy. We specifically highlight the application of these techniques in elucidating ion transport dynamics, tracking redox processes, identifying degradation pathways, and detecting interphase formation. Furthermore, we discuss the limitations, challenges, and potential pitfalls associated with each method, as well as future directions for advancing characterization techniques to better understand and optimize 2D material-based electrodes
Structures photoniques résonantes appliquées au suivi de processus spécifiques de la matière molle : vers les mesures de sédimentation et de stabilité de produits industriels
No full textThe stability of industrial products, from formulation through storage to usage, is essential to ensure their performance and quality. This thesis explores the use of resonant photonic structures for the dynamic monitoringof sedimentation and stability processes in opaque or dark products, which are difficult to analyse using commercial devices. The approach is based on the fabrication of micro-resonators made from the UV210 polymerwith quasi-surface optical detection, integrated into a simplified and cost-effective experimental platform. After characterizing hybrid SOI/UV210/SOI structures suitable for studying substances aggressive to organics,the SOI/UV210 sensors were tested on colloidal silica dispersions in water and then in a viscous medium, enabling sedimentation rate measurements. The study was extended to opaque carbon black dispersions, demonstratingthe ability to monitor the colloidal stability of absorbing substances, directly linked to industrial issues (paints, latex/silica mixtures). Finally, these micro-resonators also allowed the tracking of dynamic drying and stratificationphenomena in dairy products.La stabilité des produits industriels, de la formulation au stockage puis à l’utilisation, est essentielle pour garantir leurperformance et leur qualité. Cette thèse explore l’usage de structures photoniques résonantes pour le suivi dynamique des processus de sédimentation et de stabilité de produits opaques ou sombres, difficiles à analyserpar des dispositifs commerciaux. L’approche repose sur la fabrication de microrésonateurs en polymère UV210 avec une détection optique quasi-surfacique, intégrée à une plateforme expérimentale simplifiée et économique. Après caractérisation de structures hybrides SOI/UV210/SOI adaptées à l’étude de substances agressives pour l’organique,les capteurs SOI/UV210 ont été testés sur des dispersions colloïdales de silice dans l’eau puis dans un milieu visqueux, permettant de mesurer les vitesses de sédimentation. L’étude a été étendue à des dispersionsopaques de noir de carbone, démontrant la capacité à suivre la stabilité colloïdale de substances absorbantes, en lien direct avec des problématiques industrielles (peintures, mélanges latex/silice). Enfin, ces microrésonateurs ont aussi permis de suivre des phénomènes dynamiques de séchage et de stratification dans des produits laitiers
Devenir ingénieur : construire des habiletés entre promesse technologique et éthique de l’organisation
No full textInternational audienceCet article questionne la question des habiletés développées par les ingénieurs en formation par apprentissage et en charge de projets de transformation digitale. Dans les référentiels mobilisés pour caractériser le profil et les compétences des ingénieurs, le recours aux softs skills est utilisé pour rendre compte de la capacité à intégrer des solutions technologiques. L’analyse en situation du travail de l’ingénieur montre que l’articulation entre la technologie et les contextes socio-professionnels requiert de développer des pratiques qui prennent en compte les spécificités du travail et de l’organisation. C’est précisément la connaissance pratique de l’organisation et la mise en discussion de la technologie qui génèrent des habiletés de transformation ancrées dans les contextes productifs (« Varia »)
Integrating Data into Hydrogeophysical Models to Unveil Fluxes and River Interactions: Insights from the Orgeval Critical Zone Observatory
No full textInternational audienceQuantifying water and heat fluxes at the surface water (SW)–groundwater (GW) interface is crucial for ensuring sustainable water management and quality. However, direct field-based quantification remains challenging due to the dynamic nature of SW-GW interactions, which are influenced by poorly constrained boundary conditions and spatial hydrofacies distributions. Traditionally, these parameters are inferred through model calibration using conventional data, such as hydraulic heads and river discharge. Many regional studies have treated rivers as curvilinear GW divides, with flow either converging toward or diverging from the river center—an assumption rooted in Tóth’s theory, which correlates surface and subsurface drainage boundaries. However, this oversimplification fails to account for geological heterogeneity, river morphology, variable hydraulic conditions, and anthropogenic influences like withdrawals. While regional-scale studies commonly examine SW-GW exchanges, their coarse resolution limits the ability to resolve localized hydraulic gradients. Understanding flow dynamics in heterogeneous environments, such as alluvial plains, requires a more detailed, integrated approach. Here, we present a multi-method framework to strengthen numerical simulations and improve hydrodynamic and thermal parameter calibration in both space and time. Applied to the Orgeval Critical Zone Observatory (France), our approach estimates SW-GW fluxes using a combination of long-term hydrological data (10 years), time-lapse seismic imaging, and numerical modeling. We demonstrate how high-resolution geophysical imaging, combined with geotechnical data, enables a detailed characterization of hydrofacies and provides valuable prior constraints on hydrodynamic properties. Time-lapse seismic acquisitions offer a high-resolution view of groundwater table (WT) dynamics, with each seismic snapshot carefully inverted to capture spatial WT variations. By integrating these geophysical insights with long-term hydrogeological observations (hydraulic head and temperature), we refine parameterization within the hydrogeological modeling domain, leading to improved estimates of transient stream-aquifer exchanges. Finally, we outline future steps toward achieving a fully coupled hydrogeophysical model to further enhance SW-GW interaction predictions
Évaluation des impacts environnementaux à partir d'une ACV simplifiée pour un réseau massif MIMO distribué
No full textInternational audienceCe travail évalue l'impact environnemental des réseaux multi-antennes distribués sans cellule (CF-mMIMO), une technologie envisagée pour les futures générations de télécommunications. Bien que largement reconnus pour leur efficacité énergétique à haut débit, aucune évaluation de leur impact environnemental n'a été réalisée afin de justifier de leur pertinence, notamment par rapport aux architectures co-localisées usuelles. Dans cette étude, l'empreinte environnementale est analysée à l'aide d'une analyse du cycle de vie (ACV) simplifiée et comparée à d'autres études afin de vérifier la cohérence du modèle. Les résultats obtenus indiquent que selon les configurations choisies et les performances visées, le déploiement des réseaux CF-mMIMO peut autant être une option à faible qu'à fort impact environnemental. Enfin, l'introduction d'un modèle tenant compte de la fabrication des équipements montre que l'efficacité énergétique seule n'est pas pertinente
A Fragile Phosphate/Pyrophosphate Balance: From Essential Mineralization to Rare Calcifying Diseases
No full textInternational audiencePurpose of ReviewCalcification, the deposition of phosphate-calcium crystals, is essential for the development and function of mineralized tissues. When dysregulated, it can cause harmful effects. This review focuses on the critical role of the balance between phosphate (Pi) and pyrophosphate (PPi) in maintaining healthy mineralization and explains how disruptions in this balance contribute to rare calcifying disorders.Recent FindingsStudies have identified key regulators of PPi production and Pi generation. Recent research on rare calcifying diseases and animal models has revealed how Pi/PPi imbalances lead to ectopic calcification in soft tissues, driving disease progression.SummaryThe balance of Pi/PPi is vital for bone health and preventing pathological calcification. Disruptions in this equilibrium contribute to rare diseases. Understanding these mechanisms, supported by preclinical models, opens potential therapeutic avenues to restore balance and mitigate the impact of these diseases
Recent advances in understanding and improving the stability of 211At-radiopharmaceuticals
No full textInternational audienceAstatine-211 is more than ever a serious candidate radionuclide to achieve success of targeted alpha therapy of cancers in the close future. However, several challenges remain to be overcome in order to guarantee the translation of 211 At-labeled radiopharmaceuticals to the clinic. Particularly, the lack of biological stability of 211 At-labeling, which has been identified in early studies with astatoaryl-based compounds, is still the object of active research. This has led to two main approaches to optimize stability: i) modulation of the astatoaryl moiety, ii) binding astatine to other moieties than phenyl derivatives. In addition, improvement of the knowledge on astatine chemical properties now facilitates the design of optimally designed structures and opens new perspectives. Hypotheses have also emerged, rationalizing the potential mechanisms at stake in the in vivo degradation of the carbonastatine bond and that should facilitate the development of strategies to counter these events. In this work, we discuss the advances made in the stabilization of 211 At-labeling since the last review on the topic reported by D.S. Wilbur in 2008