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Le capitalisme chinois en pointe dans le domaine du numérique : l’exemple fulgurant de TikTok
No full textLe capitalisme chinois en pointe dans le domaine du numérique : l'exemple fulgurant de TikTokBeaucoup de sociétés chinoises ont émergé ces dernières années : les BATX (Baidu, Alibaba, Tencent, Xiaomi) mais aussi des entreprises moins connues dans le domaine de la construction, des assurances, de la pharmacie, des énergies, etc. Les plus emblématiques restent celles du numérique car bien connues dans le monde entier. A la suite de leur développement le gouvernement chinois a cherché à en reprendre le contrôle. Cette démarche est typique du capitalisme chinois qualifié appelé aussi « national capitalisme autoritaire » (https://theconversation.com/fr) mais officiellement nommé «économie socialiste de marché ». Un exemple est emblématique : le cas de TikTok, l'application de la société ByteDance fondée en 2012 par Zhang Yiming. Elle est l'application la plus téléchargée dans le monde devant Facebook et dépasse Google pour les consultations, avec un site web qui est le plus visité au monde (https://blog.cloudflare.com/popular-domains-year-in- review-2021/). Sa puissance vient de son algorithme qui repose sur le temps passé à utiliser l'application. La démarche du capitalisme chinois dans le numérique se fait ainsi en 5 phases : développement sur le marché national, conquête des marchés étrangers, réactions locales et adaptation aux règles locales, prise de contrôle par l'Etat.</div
Acute effect of light and time of day on thermal physiology, perception, and behavior
No full textInternational audienceImplementing novel, human-centric building control strategies that account for the interaction of multidomain factors, light, temperature, and time of day, can enhance occupant comfort and promote energy savings. However, their successful implementations require a robust framework that clearly explains the physiological mechanisms through which light exposure influences thermal perception and evaluation. To date, most studies have primarily relied on the hue-heat hypothesis, which attributes changes in thermal assessment solely to visual color associations, overlooking the physiological impact of light, particularly blue-enriched bright light, on the circadian rhythm and thermoregulation. In this study, we investigated the influence of light intensity on thermal physiology, perception, and behavior within a circadian context, employing skin temperature measurements, subjective questionnaires, and fan-use behavior as outcome measures. 20 healthy adults participated in four experimental sessions combining two illuminance levels (bright vs. dim, with identical spectral composition) at two times of day (07:00 and 14:00) under warm conditions, both steady-state and fan-induced dynamic ones. Results showed that skin temperature followed its natural circadian rhythm, being lower in the early morning than at midday. Notably, bright light exposure significantly suppressed the circadian rise in skin temperature in the morning, shifted thermal sensation votes from slightly warm towards neutral, and improved thermal comfort votes compared to dim light or midday exposure. This effect was evident under steady-state warm conditions and persisted following fan use. In contrast, under the fan-induced slightly cool condition, neither light intensity nor time of day significantly affected thermal assessment. These findings underscore the fundamental role of circadian physiology in thermal comfort and suggest that strategically timed light and thermal exposure can optimize comfort by aligning ambient conditions with the body’s internal rhythms
Totum‐448 Improves MASLD and Modulates Microbiota in Hamsters: Dose–Response Study and Effects of Supplementation Cessation
No full textInternational audienceABSTRACT Metabolic dysfunction‐associated steatotic liver disease (MASLD) is a global condition linked to obesity. Totum‐448, a polyphenol‐rich blend of five plant extracts and choline, was developed to target MASLD progression. This study evaluated the dose‐dependent effects of Totum‐448 and their sustainability after supplementation cessation on MASLD features and cecal microbiota. Male hamsters were fed a normal diet, a Western diet (WD), or WD supplemented with Totum‐448 (3.5% or 5% w/w) for 12 weeks (dose–response study). A parallel 18‐week on/off study included 12 weeks of Totum‐448 (5% w/w) followed by a 6‐week cessation period. Totum‐448 dose‐dependently reduced hepatic and circulating triglycerides, total cholesterol, and free fatty acids, independently of any changes in body composition. Gene markers of liver inflammation ( Tgfb1 , Il1b, Ccl2 , Il6 ) and fibrosis ( Col3a1, Vcam ) were downregulated with the highest dose of Totum‐448 only. Supplementation cessation led to a gradual rebound in serum and liver lipid levels and in relative expression of gene markers of hepatic inflammation and fibrosis, resulting in the loss of the majority of the benefits conferred by Totum‐448, although partial effects on hepatic steatosis and hepatocyte ballooning were maintained. Cecal microbiota analysis revealed modulation of the relative abundance of Acetatifactor , Alloprevotella , Lactobacillus , and Lawsonibacter , with identified correlations with certain metabolic outcomes. In conclusion, Totum‐448 demonstrated dose‐dependent improvements in key MASLD features in WD‐fed hamsters which gradually diminished after supplementation stopped. These findings underscore its therapeutic potential in MASLD management. The correlations with microbiota changes suggest a possible gut–liver axis role in its effects
Sur l’intérêt des méthodes de prospection géophysique pour étudier les sites archéologiques sur l’estran. Exemples sur la façade atlantique française.
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Sondages archéologiques sur deux sites à sel de la région de Rochefort (17), France : Nouvelles données sur l’organisation des sites et le mobilier.
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Outils linguistiques pour exprimer l’humour en coréen - en lien avec les néologismes récents
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Carbonation of recycled concrete aggregate in a fixed-bed reactor: Effects of temperature, initial water saturation degree and particle size
No full textInternational audienceAccelerated carbonation of recycled concrete aggregates (RCA) in industrial CO 2 -rich environments is a promising technique to enhance CO 2 sequestration while improving RCA properties. This study investigates the influence of temperature (50-110 • C), initial water saturation degree (0.34-0.93), and RCA particle size (0-4 mm) on carbonation efficiency in a fixed-bed reactor under controlled conditions, simulating cement plant flue gases. Results highlight that water saturation degree is a key parameter, as it influences both CO 2 transport in the pore system and the dissolution of reactive phases. Temperature significantly impacts water saturation degree evolution, which in turn affects reaction kinetics. For each initial water saturation degree, an optimal temperature maximizes carbonation, reaching degrees above 40 % after only 2 h carbonation. Particle size also influences carbonation efficiency: finer RCA exhibit higher carbonation rates. A novel Macro-TGA methodology was employed to quantify carbonate formation in 500 g samples, offering a more representative assessment compared to classical thermogravimetric analyses. Finally, water absorption tests before and after carbonation showed a slight reduction, with a maximum decrease of 2.7 % at 80 • C and 0.93 initial water saturation degree. However, no direct correlation between water absorption and carbonation degree was observed, suggesting complex porosity evolution that requires further investigation
Megafauna show pervasive yet distinct affinity to ocean fronts: the urgent need for adaptive conservation in a warming world
No full textFronts are ephemeral structures in the ocean that mark the boundaries between water masses of different properties, attracting a wide range of marine organisms, from plankton to whales.Despite their fundamental role in marine ecosystem functioning, the association with biodiversity has mainly focused on single species in regions with high data availability. Here, using multidecadal datasets on dynamical and thermal fronts, satellite tracking, and aerial observations, we assess marine megafauna associations with ocean fronts in the ecologically rich yet highly turbulent Mozambique Channel. We find that a diverse array of species associate with various ocean fronts, although the strength and type of affinity vary across taxa. Downscaled climate change simulations predict significant spatial shifts in front-rich areas by the end of the century.As climate change reshapes ocean front dynamics, adaptive management strategies will be essential to balance conservation and resource use in these critical ecosystems.Teaser: Ocean fronts attract marine megafauna, but climate change might alter these habitats, requiring adaptive conservation strategies.</p
OniscidBase: a call for contributions to a global database to advance terrestrial isopod research
No full textInternational audienceTerrestrial isopods (Isopoda: Oniscidea), commonly known as woodlice, are among the most recognisable soil-dwelling invertebrates and are crucial for soil functioning. They are widely distributed from temperate to equatorial ecosystems, and their distribution is strongly influenced by environmental factors, such as soil type, temperature and humidity. Terrestrial isopods have fascinated taxonomists for centuries, with over 4,100 described species across 568 genera and 38 or 39 families. These animals contribute significantly to key ecosystem processes, such as litter decomposition, nutrient cycling, and carbon sequestration. However, data on patterns of their diversity, abundance, or biomass, which are crucial for assessing their importance in ecosystem functioning worldwide, are lacking. This is partly due to the incomplete taxonomy in regions such as the tropics and the scattered nature of local georeferenced datasets. To better understand the global taxonomic patterns, species distributions, and functional roles of terrestrial isopods, we call for the compilation of a comprehensive global database that integrates taxonomy, georeferenced species records, and trait data. This database would help answer fundamental questions about the response of terrestrial isopods to environmental changes and their role in ecosystem functioning and soil health. OniscidBase, a recently launched initiative, aims to consolidate such data, facilitating the analysis of taxonomic gaps and assessing the distribution and functional importance of terrestrial isopods. The database aims to include georeferenced data on the distribution, abundance and biomass of terrestrial isopod species, and metadata on environmental parameters. Our main goals are to strengthen the taxonomic backbone for terrestrial isopods, make distribution data available for macroecological studies, and collect trait data to understand species responses to environmental changes and effects on soils. Using these data leads to a deeper understanding of the importance of terrestrial isopods as components of terrestrial ecosystems and, at the same time, highlights future research directions