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Propriétés optoélectroniques et structure des matériaux aux échelles nanométriques
No full textNational audienceLa science des matériaux semi-conducteurs pour la détection/absorption de la lumière ou les applications photoniques sont au cœur de nombreux développements technologiques récents, afin de répondre aux grands enjeux du XXIe siècle, par exemple dans le domaine de la santé, de l’énergie propre et abordable, des capteurs environnementaux, de l’informatique ou des communications.Dans ce contexte, la réalisation de nanostructures présentant des propriétés physiques dédiées, et en particulier des propriétés optiques ou électro-optiques adaptées à l’application, est un enjeu important. Elle s’accompagne toutefois inévitablement de la formation de plusieurs types de défauts structurels impactant leurs propriétés.Dans cette contribution, le lien entre les défauts structurels ou cristallins à l’échelle nanométrique et les propriétés optoélectroniques des semi-conducteurs sera tout d’abord présenté. Nous passerons ensuite en revue les différents outils de caractérisation optique couramment utilisés pour les nanostructures, que ce soit pour l’émission ou la collecte de lumière. Enfin, des perspectives seront données sur le développement des outils de caractérisation de photons uniques, dans le contexte du développement récent des technologies quantiques
When Machines Feel and Cooperate: Engineering Human-Cyberphysical Synergy
No full textrevue Télécom Paris - réseau alumni Télécom Pari
Les conceptions de la recherche à l’œuvre dans la formation à et par la recherche : table ronde
No full textInternational audienceLa formation à la recherche par la recherche, vue à travers les ingénieries coopérative
Un usage de robot de sol dans une visée inclusive
No full textInternational audienceNous nous intéressons à l’acquisition des connaissances spatiales chez des élèves de cycle 3 (10 ans) utilisant un robot de sol, en France. Nous choisissons de mettre en œuvre une situation didactique dans une classe, dont certains élèves rencontrent des difficultés d’apprentissage durables. Notre étude exploratoire organisée en ingénierie coopérative va nous permettre d’analyser ces premières mises en œuvre et de concevoir des situations accessibles à tous les élèves
Studying International Sport Competitions in an Environmental Perspective
No full textInternational audienc
Writing and publishing mixed methods research in the social sciences: Editorial introduction to the mixed methods section of BMS
No full textInternational audienceDepuis une quinzaine d’années, les publications de sciences sociales sur les méthodes mixtes ou mobilisant des méthodes mixtes semblent connaître une croissance importante en France comme à l’international. Si cette mobilisation des méthodes mixtes n’est pas en soi nouvelle, on observe actuellement un renouveau des débats autour de pratiques de combinaison et d’articulation des méthodes qualitatives et quantitatives et surtout une montée en puissance des réflexions théoriques sur les stratégies de recherche dites « mixtes ». Ce texte éditorial introduit la section Méthodes mixtes du BMS. Après être revenu brièvement sur le développement des méthodes mixtes et les enjeux qu’il soulève pour les sciences sociales du XXIème siècle, ce texte justifie la section par la nécessité de compléter « l’inventaire des problèmes d’intégration », de proposer des pistes alternatives de classification des stratégies de recherche dites mixtes et tout simplement de contribuer à la promotion à la fois du pluralisme méthodologique et la rigueur de la démarche de research design en sciences sociales.Over the past fifteen years, there has been significant growth in social science publications on mixed methods research, both in France and internationally. While the use of mixed methods is not new, we are currently witnessing a revival of debates around how qualitative and quantitative approaches are combined and articulated – and, more importantly, a growing body of theoretical reflection on so-called “mixed” research strategies. This editorial introduces the launch of the Mixed Methods section of the BMS. After quickly reviewing the evolution of mixed methods and the challenges they pose for 21st-century social sciences, this text argues for the relevance of this new section. It highlights the need to further address the “integration problems”, to propose alternative frameworks for classifying mixed research strategies, and, more broadly, to promote both methodological pluralism and rigor in research design within the social sciences
F-BIAS: Towards a distributed national core facility for bioimage analysis
No full textInternational audienceWe discuss in this article the creation and organization of a national core facility for bioimage analysis, based on a distributed team. F-BIAS federates bioimage analysts across France and relies on them to deliver services to the researchers of this territory. The main challenge in implementing this structure is to ensure significant scientific value to the analysts, thereby encouraging their active participation and persuading their respective host teams to support their involvement. F-BIAS accomplished this by creating a professional network that mitigates the negative effects of isolation experienced by its members, who are often the sole bioimage analyst within their local teams, and fosters the development of their technical skills. In a second phase we capitalized on F-BIAS to create a virtual, remotely-operating core facility for bioimage analysis, offering consultations and collaborative project services to the scientific community of France. The services are organized so that they also contribute to the technical proficiency of the analysts. To promote the creation of similar structures, we present and discuss here the organization of this nationally distributed bioimage analysis service core, highlighting successes and challenges
Salty Crews: Salt and Its Materiality in Sailors Food, 17th and 18th Centuries
No full textInternational audienc
Evolution of Production Specialization and Factor Accumulation in Sub‐Saharan and North Africa
No full textInternational audienceDespite trade liberalization and regional economic integration policies, the level of trade and specialization in Africa is stagnating. This long‐term observation contrasts with recent developments in Africa since the 2000s. This study aims to assess how changes in factor endowments affect the specialization pattern of production, exploring the underlying neoclassical determinants. We used a global panel dataset of six industries belonging to 25 sub‐Saharan and North African countries from 1980 to 2019 to empirically investigate the impact of factor endowments on specialization in production. To achieve this, we opt for a feasible generalized least squares method and impulse response functions by using labor abundance, agricultural land abundance, and physical capital abundance as exogenous variables and the share of value added in GDP as a proxy for specialization in production. Our results show (i) a differentiated role for factors of production in specialization, (ii) that factors such as public capital and skilled human capital are still underexploited in several economic regions, (iii) a persistent specialization in primary sectors, (iv) service sectors are gradually gaining in importance, and (v) a neglect of manufacturing due to the underexploitation of public and private capital. These findings highlight the need to adopt appropriate strategies to strengthen sectoral competitiveness
Hemoglobin in cardiogenic shock: the lower, the poorer survival
No full textInternational audienceBackground: Cardiogenic shock (CS) is a severe hemodynamic condition with high mortality. Although extremely frequent in daily practice, the impact of anemia in CS is largely unknown. This study focuses on the consequences of low hemoglobin (Hb) level on the outcomes of CS patients.Methods: FRENSHOCK is a prospective registry including 772 CS patients from 49 centers. One-month and one-year mortalities were analyzed according to the admission level of Hb.Results: Among 754 patients, 71.8% were male, with a mean age of 65.8 (± 14.8) years, and 361 (47.9%) presenting with anemia. Four groups were defined, depending on admission Hb levels by quartiles: Q1: Hb < 11.0 g/dL, Q2: Hb 11-12.6 g/dL, Q3: Hb > 12.6-14 g/dL, and Q4: Hb > 14.0 g/dL. Patients from the Q1 group required more frequent renal replacement therapy and norepinephrine. A significant increase in all-cause mortality was observed across Hb quartiles at 1 month (Ptrend = 0.035) and 1 year (Ptrend < 0.01). Q1 patients had 1.64 times higher mortality at 1 month (1.09-2.47, p = 0.02) and 2.53 times higher mortality at 1 year (1.84-3.49, p < 0.01) compared to Q4. The negative effect of low Hb level was confirmed in multivariate Cox regression adjusted for baseline characteristics, and was stronger in men, non-ischemic CS, patients without CKD and patients aged < 67 years.Conclusion: Anemia is a common condition frequently intertwined with CS worsening both short- and long-term mortality. Further randomized studies are warranted to understand its mechanisms and adapt the transfusion strategy