HAL - La Rochelle Université, Archives Ouvertes
Not a member yet
19516 research outputs found
Sort by
Histoire des idées politiques (3e éd.)
No full textInternational audienceUne présentation chronologique de l'évolution des Idées Politiques, de l'Antiquité grecque jusqu'au XXe siècl
Effect of a polyphenol-rich extract on LDL cholesterol in mild to moderate hypercholesterolemia: a randomized, double-blind, placebo-controlled trial
No full textInternational audienceBackground/ObjectiveHypercholesterolemia is a well-known risk factor for cardiovascular disease. This clinical trial evaluated the effects of TOTUM-070, a polyphenol-rich blend of plant extracts, on lipid metabolism in individuals with moderate hypercholesterolemia.Subjects/MethodsThis was a 6-month, multicenter, randomized, double-blind, placebo-controlled trial. Individuals not receiving lipid-lowering treatment and with fasting low-density lipoprotein cholesterol (LDL-C) between 1.3 and 1.9 g/L received TOTUM-070 (5 g/day) or placebo. The primary outcome was the change in fasting LDL-C. Secondary endpoints included safety, changes in the lipid profile, anthropometric measurements, and gut microbiome composition.ResultsA total of 120 subjects (mean age:53.1 ± 10.3 years; BMI: 25.9 ± 3.7 kg.m2; 69.2% women; baseline LDL-C: 1.44 ± 0.23 g/L) were included and randomized. TOTUM-070 was well tolerated. After 6 months, fasting LDL-C was reduced in the TOTUM-070 group compared with the placebo group (Mean estimate: 1.31 ± 0.03 [1.25 ; 1.37] vs 1.41 ± 0.03 [1.35 ; 1.47], p = 0.0041). Compared with placebo, TOTUM-070 also reduced total cholesterol (p < 0.01), non-high-density lipoprotein cholesterol (non-HDL-C) (p < 0.001), triglycerides (p < 0.05), apolipoprotein (apo)B100 (p < 0.01), the apoB100/apoA1 ratio (p < 0.01), oxidized LDL (p < 0.05), and body weight (–1.4 kg; p < 0.001). Furthermore, a decrease in the abundance of Dorea in fecal samples was observed in the TOTUM-070 group.ConclusionsThis clinical trial showed that supplementation with TOTUM-070 significantly lowers LDL-C and improves other lipid parameters in subjects with moderate hypercholesterolemia. As a polyphenol-rich plant-based blend, TOTUM-070 represents a promising non-pharmacological strategy that could complement lifestyle modifications for the management of early-stage hypercholesterolemia
How does a DHA-deficient diet affect sardines' behaviour and metabolic rates?
No full textInternational audienceThe production of n-3 highly unsaturated fatty acids (n-3 HUFA), and in particular DHA (docosahexaenoic acid) by primary producers is tending to decrease as a result of global change, which can have cascading effects on higher tropic levels. Indeed, these molecules are crucial for consumers such as small pelagic fishes, who get them mainly from their diet, to maintain their physiological and behavioural functions. Due to their high ecological, economic and social importance, any changes affecting small pelagic fishes may have direct and indirect repercussions on human populations. In that context, the aim of this study was to measure the impact of a limited trophic availability of DHA on the physiological and behavioural performances of European sardines (Sardina pilchardus). For six months, adult sardines were experimentally fed either a control or a DHA-deficient diet. We assessed DHA levels in tissues, measured the metabolic rates of sardines using group respirometry and analysed their behaviour (swimming speeds, nearest neighbour distance, number of changes of direction), both routinely and during feeding. Dietary DHA deficiency was evidenced in the liver and muscle, but not in the eyes and brain where DHA was more present than in diet, suggesting a preferential retention rate or a possible activation of n-3 HUFA synthesis pathways. These results were associated with morphophysiological indices (relative condition index, specific growth rate, hepato-, gonado- and cerebro-somatic indices), behaviour and metabolic rates globally unchanged. Individuals fed a DHA-deficient diet maintained high oxygen consumption at night, showing possible deregulation of the circadian rhythm, and had a significantly lower nearest neighbour distance, in contrast to individuals fed a standard diet. Altogether, these results suggest that adult European sardines are capable of developing mechanisms to cope with a long-term deficiency of DHA in their food, although it seems necessary to better understand the energy trade-offs involved
Oceanic regions shape the composition of the Antarctic plastisphere
No full textInternational audienceAntarctica, once considered pristine, is increasingly threatened by plastic pollution, with debris found in its waters, sediments, sea ice, and biota. Here, we provide a comprehensive molecular survey of both prokaryotic and eukaryotic diversity on plastics around the Antarctic Peninsula, addressing a gap in existing research. Using eDNA metabarcoding, we identified diverse communities, with Pseudomonadota and Bacteroidota dominating prokaryotic communities, while Gyrista (mostly diatoms), Fungi and Arthropods were prevalent among eukaryotes. Geographic location significantly influenced community composition, with differences between the Bransfield Strait and the Gerlache Strait/Bellingshausen Sea. Polymer type and plastic shape did not impact species richness or community structure. These findings offer new insights into the complexity of the Antarctic plastisphere, highlighting potential impacts on biodiversity, ecosystem functions, and the broader implications of marine plastic pollution
The Perception of the Chinese Language by the “King’s Mathematicians” in the Age of Enlightenment
No full textInternational audienceAbstract In 17th- and 18th-century Europe, the biblical myth of the Tower of Babel was still very much alive. People wondered what this original language of mankind, lost for millennia as a result of divine punishment, might be. When, in the final years of the 17th century, Louis XIV and Colbert decided to launch a Jesuit mission, and the Jesuits were promoted to “Mathematiciens du Roi” (King’s Mathematicians), Europe, and France in particular, discovered China and, of course, its millennia-old language, based on a writing system resembling hieroglyphics and thus reminiscent of ancient Egypt, the debate between scholars, theologians and philosophers took on new momentum
La maîtrise de la métallurgie permet-elle de prévenir le risque de fragilisation par l’hydrogène ?
No full textInternational audienc
About the Implication of Grain Boundaries and Precipitates on the Hydrogen Embrittlement Mechanisms of Nickel Base Alloys
No full textInternational audienc
La Fragilisation par l’hydrogène : un défi métallurgique et multi-échelle pour la durabilité des structures ?
No full textInternational audienc
Zinc Isotope Fingerprints in Juvenile Fishes from Estuarine Nurseries with Different Pollution Histories: Perspectives for Environmental Monitoring and Fish Ecology
No full textInternational audienceZinc (Zn) isotopes are effective tracers of Zn cycling in marine environments and hold strong potential for ecological applications, yet they remain underexplored. This study analyzes Zn concentrations and isotope compositions (δ66Zn) in 96 juvenile European seabass (Dicentrarchus labrax) and common sole (Solea solea) from three French estuarine nurseries─Seine, Loire, and Gironde─each with distinct Zn pollution histories. Seabass from the three estuaries exhibit similar trends in Zn bioaccumulation (body burden) and biodilution (concentration) with an increasing size and age. However, significant δ66Zn differences among estuaries indicate that each system “stamps” a unique isotopic fingerprint on local fish populations. Intraestuarine variability among seabass age classes (1–4 years) is smaller than interestuarine differences. Juvenile soles consistently display higher δ66Zn values than seabass of similar ages, suggesting that species-specific Zn homeostasis and ecological factors influence isotope compositions. Across estuaries, δ66Zn patterns in fish mirror those in sediments, indicating that Zn sources drive the isotope compositions. These results confirm that anthropogenic Zn circulates through local food webs with both environmental and dietary sources influencing fish isotope compositions alongside homeostatic processes. Overall, Zn isotope analysis in juvenile seabass and common sole provides new insights for monitoring anthropogenic Zn bioaccumulation and elucidating dietary niches in fish ecology
"Survivre au féminin : les nouvelles robinsonnes du monde postmoderne"
No full textInternational audienceLa définition que nous donne le CNRTL1 du mot « aventurier » et son féminin « aventurière » apparaîtparticulièrement éclairante sur le clivage entre les représentations des genres. Ainsi, si l’aventurier est celuiqui aime les aventures extraordinaires et court le monde, au féminin, il se dote d’une connotation négativepour qualifier une personne sans état ni fortune vivant d’expédients. Or, s’intéresser à la figure littéraire de larobinsonne, comme nous proposons de le faire dans cet article, c’est, de fait, questionner le changement degenre et sa redéfinition car, en se glissant dans la peau de ce personnage mythologique, paradigmatique del’aventurier, la femme devient une aventurière au même titre que son correspondant masculin. Loin de laconnotation morale négative qui lui est associée, l’aventurière, et plus particulièrement la robinsonne, renoueavec une force vitale devenue nécessaire à sa survie et réinvestit le personnage de l’aventurier d’uneféminisation positive. Dans cet article, après avoir défini l’hypotexte de départ que constitue le roman de DanielDefoe, Robinson Crusoé écrit en 1719, nous nous intéresserons plus particulièrement à deux robinsonnades duXXe siècle au féminin : Le Mur invisible [Die Wand] de Marlen Haushofer publié en 1963 et Dans la forêt [Intothe forest] de Jean Hegland publié en 1996. Fidèles aux caractéristiques du genre, ces deux romanscontemporains narrent les aventures de personnages, isolés par accident de la société normée, qui vont devoirapprendre à mettre en place des moyens de leur survie. Les particularités de ces deux réécritures du mythe deRobinson tiennent, quant à elles, à la féminisation des protagonistes et à la radicalisation du contexte situédans un monde où tout est à reconstruire. Nous nous demanderons ainsi en quoi les héroïnes de ces deuxromans post-apocalyptiques, dont les succès de réédition et les adaptations récentes au cinéma nous disenttoute l’actualité, incarnent les nouvelles aventurières d’un monde postmoderne et que peut signifier cechangement de genre. Notre étude portera dans un premier temps sur la figure fondatrice du mythe littéraire: Robinson Crusoé de Daniel Defoe puis sur sa déclinaison au féminin. Enfin, nous nous attacherons à définirla symbolique des espaces occupés par nos trois survivants ou survivantes : l’île, la montagne puis la forêt