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Correction: Creation and validation of a roadside rescue skills scale for training pre-hospital medical teams: the RoadRes-Q scale
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What are the determinants of permanent and temporary non-take-up of the French minimum-income benefit?
No full textInternational audienceWe investigate the determinants of non-take-up of the French minimum-income benefit, the Active Solidarity Income (Revenu de Solidarité Active [RSA]), using the Tax and Social Income Survey and distinguishing between people in situations of either permanent or temporary eligibility. We use the monthly dimension of the dataset in order to study the dynamics of non-take-up. We find that poverty levels in the department of residence and having two or more children decrease the probability of RSA non-take-up, in cases where individuals are permanently or temporarily eligible while professional inactivity, receiving rental resources and living as a couple increase the likelihood of submitting a claim in both cases. In the case of permanent eligibility, we find that non-take-up of RSA in a given quarter increases the probability of non-take-up in the following quarter. Moreover, the amount of the RSA, the level of sanctions, living in a deprived area and the repeated administrative exchanges between claimants and welfare agencies are important factors affecting non-take-up in the case of permanent eligibility while take-up for the Activity Bonus and welfare agencies’ credibility in delivering accurate and reliable information, are salient in the temporary eligibility case
Heparanase 1 produced by keratinocytes contributes to psoriatic inflammation by promoting neutrophil infiltration
No full textInternational audiencePsoriasis is a chronic inflammatory skin disease characterized by keratinocyte hyperproliferation, abnormal differentiation, and immune cell infiltration, driven by a pro-inflammatory microenvironment involving cytokines, and diverse enzymatic activities. Among them, are the two heparanases, Heparanase 1 (HPA1), an endo-β-D-glucuronidase that cleaves heparan sulfate and contributes to extracellular matrix remodeling and inflammatory cell recruitment, and Heparanase 2 (HPA2), which lacks enzymatic activity and acts as an antagonist of HPA1. While their roles are established in cancer and inflammation, their involvment in psoriasis remains underexplored, despite the intense matrix remodeling and inflammatory cell recruitment characteristic of the disease. We found increased HPA1 and decreased HPA2 expression in human psoriatic lesions, with normalization following anti-TNF-α therapy. In vitro, HPA1 expression and activity are enhanced in keratinocytes stimulated with the psoriasiform cytokine combination IL-1α, IL-17A and TNF-α, while HPA1 inhibition dampens pro-inflammatory cytokine production. In vivo, imiquimod-induced psoriasiform inflammation in mice shows similar patterns of Hpa1 upregulation, Hpa2 downregulation, and Hpa1-dependent chemokines production and neutrophils recruitmentto lesional sites. These findings suggest that HPA1 and HPA2 contribute to the establishment and/or maintenance of psoriatic lesions. Modulating their expression or activity could provide a more precise understanding of their contribution to skin inflammation
Potential health benefits of cold‐water immersion: the central role of PGC‐1α
No full textInternational audienceCold‐water immersion (CWI) elicits a coordinated thermoregulatory and stress‐response programme that may converge on molecular pathways linked to peroxisome proliferator‐activated receptor‐γ co‐activator‐1α (PGC‐1α), a master regulator of mitochondrial biogenesis and a coordinator of angiogenesis, antioxidant defence and metabolism. Through activation of peripheral cold receptors (e.g. TRPM8), CWI triggers sympathetic noradrenaline release and hypothalamic–pituitary–thyroid axis stimulation (TSH→D2→T3), driving β‐adrenergic/cAMP–PKA–p38MAPK–CREB signalling that could robustly upregulate PGC‐1α and uncoupling protein‐1 in brown adipose tissue and skeletal muscle. Concurrent shivering‐induced Ca2+ fluxes engage calcium/calmodulin‐stimulated protein kinase II and calcineurin, enhancing PGC‐1α expression in an AMP‐activated protein kinase (AMPK)‐independent manner. Elevated PGC‐1α coactivates nuclear respiratory factors (NRF1/NRF2) and mitochondrial transcription factor A to expand mitochondrial content and oxidative capacity, while upregulating key antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase). Together with oestrogen‐related receptor α, PGC‐1α can co‐activate vascular endothelial growth factor, a pathway compatible with angiogenesis and improved perfusion; however, in humans the link to CWI remains indirect and is largely limited to acute molecular responses. Downstream metabolic adaptations, including increased fatty acid oxidation (via carnitine palmitoyltransferase 1, peroxisome proliferator‐activated receptors α/γ and AMPK) and fibroblast growth factor 21 secretion, enhance insulin sensitivity and energy expenditure. Most of the evidence currently rests on molecular signalling data, heterogeneous study designs, or acute gene expression responses. Direct evidence for increased mitochondrial content, improved mitochondrial function, or long‐term health benefits in humans is scarce. Therefore, this article introduces a hypothetical dose–response relationship, linking immersion time to proposed health benefits and death, and provides practical recommendations for safe CWI protocols. imag
Transferts et Francophonie : la réception par le Japon des concepts français de droit public financier
No full textInternational audienceFrom a historical point of view, the financial system of the Japanese State is largely influenced by the French financial system. The way the Japanese State operates is in fact the result of a French legal tradition dating back to the 19th century. Although France and Japan share the same origins in public financial law, the influence of the French legal model is neither claimed nor even clearly perceived by Japanese academics and practitioners. However, this "f/Francophony" of "transfers", legal "models" and "systems" is very real in Japan. It was particularly evident in the management of the health crisis, where the convergence of the budgetary responses of the French and Japanese governments was striking, over and above cultural, economic and social differences, even though the two societies were not affected in the same way by the pandemic. These similarities in budgetary approaches and policies in the face of the health crisis point to a public financial law of crisis with reciprocal influences, as Japanese legal expertise concerning major disasters is already being mobilised in France in anticipation of the management of future climatic crises.Du point de vue historique, le régime financier de l’État japonais est largement influencé par le système financier français. Le fonctionnement de l’État japonais est, en effet, issue d’une tradition juridique française qui remonte au XIXe siècle. Si la France et le Japon ont un droit public financier aux origines communes, l’influence du modèle juridique français n’est ni revendiquée ni même clairement perçue par la doctrine et les praticiens japonais. Cette « F/francophonie » des « transferts », des « modèles » et « systèmes » juridiques est pourtant bien réelle au Japon. Elle s’est notamment exprimée à travers la gestion de la crise sanitaire où la convergence des réponses budgétaires des États français et japonais est frappante par-delà les différences culturelles, économiques et sociales et alors même que les deux sociétés n’ont pas été touchées de la même manière par la pandémie. Ces similitudes dans les approches et politiques budgétaires face à la crise sanitaire dessinent un droit public financier de crise avec des influences réciproques car l’expertise juridique japonaise concernant les grandes catastrophes est d’ores et déjà mobilisée en France en prévision de la gestion des futures crises climatiques
Épidémies adolescentes au temps des réseaux sociaux
No full textInternational audienceDesde la creación de Facebook en 2004, la expansión de las redes sociales es un hecho indiscutible, especialmente entre los adolescentes. En el ámbito virtual, encuentran un espacio de elaboración psíquica y vínculos identificatorios que contribuyen a la construcción de su identidad. Sin embargo, se ha observado que el internet y sus redes también dan lugar a fenómenos epidémicos y de influencia, basados en una identificación imaginaria con sus semejantes y en síntomas que socavan su subjetividad. Los objetos tecnológicos pueden dar lugar a pulsiones ilimitadas y a una tiranía de la imagen, pero también crean vínculos verbales. Se puede encontrar un nuevo acuerdo para el adolescente en torno a la pulsión, la imagen y el lenguaje.Depuis la création de Facebook en 2004, l’expansion des réseaux sociaux n’est plus à confirmer, notamment auprès des adolescents. Sur la scène du virtuel, il trouve un espace d’élaboration psychique et de liens identificatoires qui participent de sa construction identitaire. Pour autant, constat est fait qu’internet et ses réseaux ouvrent aussi sur des phénomènes épidémiques et d’influence, qui reposent sur une identification imaginaire au semblable et à des symptômes qui court-circuitent sa subjectivité. Si les objets technologiques ouvrent sur un illimité pulsionnel et sur une tyrannie de l’image, ils font aussi lien de parole. Un nouvel arrangement avec la pulsion, l’image et la langue peut être trouvé pour l’adolescent
TCAD simulations of a barrier structure designed to improve the performance of very-low bandgap InAs/InAsSb thermophotovoltaic cells
No full textInternational audienceVery-low bandgap TPV cells (< 0.4 eV) usually require cryogenic cooling (∼ 70 K) because of their high intrinsic dark current densities. To mitigate this effect, a barrier structure combined with a gallium-free InAs/InAsSb absorber, inspired by infrared photodetectors, is studied through optoelectronic TCAD simulations. This analysis reveals that the power output of the cell could be increased by 24% at 200 K thanks to this design, when compared to an equivalent PIN structure. The quantitative effects of contact doping, parasitic absorption, and carrier diffusion length are discussed in detail. An optimum design is extracted, predicting a power output of 0.3 W/cm2 and pairwise efficiency of 16% at 200 K under the illumination of an 800 °C black-body emitter. The physical mechanisms limiting the performance of the cell at higher temperatures are identified, and a guideline for future improvements is proposed
Hypothalamic Astrocytes Exhibit Glycolytic Features Making Them Prone for Glucose Sensing
No full textInternational audienceIn the hypothalamus, detection of energy substrates such as glucose is essential to regulate food intake and peripheral energy homeostasis. Metabolic interactions between astrocytes and neurons via lactate exchange have been proposed as a hypothalamic glucose‐sensing mechanism, but the molecular basis remains uncertain. Mouse hypothalamic astrocytes in vitro were found to exhibit a stronger glycolytic phenotype in basal conditions than cortical astrocytes. It was associated with higher protein expression levels of the Pyruvate Kinase Isoform M2 (Pkm2) and its more prominent nuclear localization. In parallel, hypothalamic astrocytes also expressed higher levels of the monocarboxylate transporter Slc16a3 (Mct4), which were dependent on Pkm2 expression. The stronger Mct4 expression in hypothalamic versus cortical astrocytes is an intrinsic characteristic, as it was also present after their direct isolation from adult mouse tissue. The high lactate release capacity of hypothalamic astrocytes was demonstrated to depend on the expression of Mct4, but not Mct1. Unlike cortical astrocytes, hypothalamic astrocytes in culture do not respond to glutamate with enhanced glycolysis, but instead, they modulate their lactate production according to glucose concentrations in an AMPK‐dependent manner, an effect observed in both mouse and human hypothalamic astrocytes in vitro. Our study shows that hypothalamic and cortical astrocytes are geared to have distinct glycolytic responses to glucose and glutamate, respectively. These results reveal a metabolic specialization of astrocytes in order to fulfill distinct area‐specific functions: glucose‐sensing in the hypothalamus versus activity‐dependent neuronal energetic supply in cortical regions
Spectral proper orthogonal decomposition of street canyon flow dynamics and its application to time-domain reconstruction
No full textInternational audienceMitigating the risks associated with air pollution is one of the important aspects of planning urban spaces. Fast and accurate models are required for a viable design campaign and to reproduce the unsteady dynamics of the air flow responsible for the pollutant dispersion. However, modeling and prediction of such flows is challenging due to the turbulent nature of the flow. Canopy fluid dynamics presents substantial computational challenges due to their inherently multi-scale and strongly non-linear nature. Since numerical simulations become computationally prohibitive as the flow complexity increases, sophisticated methodological approaches to reduce dimensionality while preserving essential dynamical characteristics have to be developed. This work focuses on obtaining data-driven ROMs based on time-resolved, two-dimensional flow field snapshots obtained from numerical simulations. The important ingredient of a feasible ROM is the latent space that can capture the relevant unsteady features and account for the variability of urban flows. The spectral proper orthogonal decomposition (SPOD) technique is well suited as it has been demonstrated to decompose the canyon flow into scale-specific fluctuation patterns that can be associated with known physical mechanisms. Once the relevant SPOD mode has been identified, a time-domain approach is used to reproduce the dynamics and verify the resolution of large- and small-scale structures