173 research outputs found
On the bounded cohomology of semi-simple groups, S-arithmetic groups and products
We prove vanishing results for Lie groups and algebraic groups (over any
local field) in bounded cohomology. The main result is a vanishing below twice
the rank for semi-simple groups. Related rigidity results are established for
S-arithmetic groups and groups over global fields. We also establish vanishing
and cohomological rigidity results for products of general locally compact
groups and their lattices
Structures spécifiques des peuplements de rongeurs d'agro-écosystèmes et d'écosystèmes « naturels » de la Guadeloupe et de la Martinique
The Muridae rodent community of Guadeloupe and Martinique (French West Indies)
includes 3 alien species: the Ship Rat (Rattus rattus), the Norwegian Rat (Rattus norvegicus)
and the House Mouse (Mus musculus). A 26,740 trap-night effort conducted under standardized
sampling methods showed a strong heterogeneity of the species frequency distribution
among 4 agricultural ecosystems (sugar cane, banana, cassava and watermelon) and 3 "natural"
ones (tropical rain forest and islands or islets covered either totally or partially by a dry
vegetation). A second step of the analysis conducted at a smaller space scale, from the surrounding
ecosystems of the cultivated areas to the inside of these ones, gave the same result.
The House Mouse constituted the majority of the captures in the agricultural ecosystems
(56% for the total and 84% for sugar cane specifically). This species is well represented
inside the cultivated area and poorly outside. The Ship Rat is well represented in the "savannah"
and "thorn-scrub", and in tropical rain forest, habitats that surround sugar cane and
banana fields respectively. Statistically less numerous than the others, the Norwegian Rat was
nevertheless well represented in the cultivated area devoted to watermelon and cassava, and
concentrated in the field margins. The build-up and the optimisation of strategies for controlling
the alien rodents in tropical islands are discussed in relation to these results. The build-up
of sampling strategies to evaluate epidemiological and environmental risks due to these alien
rodents is also discussed. This last discussion was done in the light of a new result showing
that 57% of sampled Guadeloupe House Mice hosted Leptospira interrogans on their kidneysLe peuplement de rongeurs muridés de la Guadeloupe et de la Martinique est constitué de 3 espèces allochtones, le Rat noir (Rattus rattus), le Rat surmulot (Rattus norvegicus) et la Souris domestique (Mus musculus). Un effort
d'échantillonnage standardisé de 26 740 nuits-pièges a permis de mettre en évidence une grande hétérogénéité de la distribution de ces espèces au sein d'un ensemble de 4 agro-écosystèmes (canne à sucre, banane, manioc et pastèque) et de 3 écosystèmes naturels (forêt tropicale humide et 2
types d'îles ou îlots à végétation xérophile). Une analyse des résultats, conduite à une échelle spatiale plus fine, depuis les milieux encaissant les parcelles cultivées jusque dans celles-ci, aboutit à la même conclusion. Les Souris domestiques constituent la majorité des captures
réalisées sur l'ensemble des agro-écosystèmes étudiés (56 % pour l'ensemble et jusqu'à 84 % pour les agro-écosystèmes canniers). L'espèce est fortement représentée au sein des parcelles cultivées et faiblement dans les milieux encaissants. Le Rat noir est fortement représenté dans les
savanes et formations d'épineux d'une part, et la forêt tropicale humide d'autre part, ces milieux constituant respectivement l'environnement immédiat des champs de canne et des bananeraies. Le Surmulot, significativement moins abondant que les espèces précédentes, est cependant bien
représenté dans les agro-écosystèmes consacrés aux cultures vivrières et se concentre dans l'écotone que constitue la marge des parcelles cultivées. Ces résultats induisent une réflexion sur l'optimisation des stratégies de lutte anti-rongeurs en vigueur, d'une part, et des stratégies
d'échantillonnage destinées à évaluer des risques épidémiologiques ou environnementaux en rapport avec la présence de ces rongeurs, d'autre part. Ils sont discutés en relation avec la mise en évidence récente du portage rénal de Leptospira interrogans par 57 % des souris d'un échantillon
collecté à la Guadeloupe
Classification of Reductive Monoid Spaces Over an Arbitrary Field
In this semi-expository paper we review the notion of a spherical space. In
particular we present some recent results of Wedhorn on the classification of
spherical spaces over arbitrary fields. As an application, we introduce and
classify reductive monoid spaces over an arbitrary field.Comment: This is the final versio
Lipolysis kinetics of milk-fat catalyzed by an enzymatic supplement under simulated gastrointestinal conditions
[EN] Pancreatic insufficiency is a clinical manifestation characterized by the in-ability of the pancreas to release enough pancreatic enzyme into the small intestine, necessary to digest intraluminal nutrients. The lack of digestive enzymes leads to the difficulty to absorb nutrients, which drives in infants, to malnutrition and lack of growth and development, due to the loss of calories. These patients generally need oral administration of enzymes to favor lipolysis and absorption of lipids from foods. However, there are a number of food related factors (matrix, type of fat, etc.) and digestive environment (intestinal pH, bile concentration, among others), which will influence the digestibility of nutrients.
In this study, an "in vitro" digestion model was used to characterize the kinetics of the lipolysis of milk-fat catalyzed by an enzymatic supplement. Different intestinal conditions (pH (6, 7 and 8) and bile concentrations (1, 5 and 10 mml L-1)) were simulated, using a fixed concentration of supplement. Gastro-Intestinal conditions, significantly affected lipolysis. High pH and bile concentrations were translated into low values of the Michaelis-Menten constant and high values of the catalytic constant. The kinetic parameters obtained from this work allowed estimating the dose of enzymatic supplement required to optimize the lipolysis of milk-fat under different intestinal environments, sufficient and insufficient pancreatic conditions.Authors of this paper, on behalf of MyCyFAPP consortium, acknowledge the European Union and the Horizon 2020 Research and Innovation Framework Programme for funding the above-mentioned project under grant agreement number 643806.Peinado Pardo, I.; Larrea Santos, V.; Heredia Gutiérrez, AB.; Andrés Grau, AM. (2018). Lipolysis kinetics of milk-fat catalyzed by an enzymatic supplement under simulated gastrointestinal conditions. Food Bioscience. 23:1-8. https://doi.org/10.1016/j.fbio.2018.02.011S182
Fat emulsion intragastric stability and droplet size modulate gastrointestinal responses and subsequent food intake in young adults
Background: Intragastric creaming and droplet size of fat emulsions may affect intragastric behavior and gastrointestinal and satiety responses.Objectives: We tested the hypotheses that gastrointestinal physiologic responses and satiety will be increased by an increase in intragastric stability and by a decrease in fat droplet size of a fat emulsion.Methods: This was a double-blind, randomized crossover study in 11 healthy persons [8 men and 3 women, aged 24 ± 1 y; body mass index (in kg/m2): 24.4 ± 0.9] who consumed meals containing 300-g 20% oil and water emulsion (2220 kJ) with 1) larger, 6-μm mean droplet size (Coarse treatment) expected to cream in the stomach; 2) larger, 6-μm mean droplet size with 0.5% locust bean gum (LBG; Coarse+LBG treatment) to prevent creaming; or 3) smaller, 0.4-μm mean droplet size with LBG (Fine+LBG treatment). The participants were imaged hourly by using MRI and food intake was assessed by using a meal that participants consumed ad libitum.Results: The Coarse+LBG treatment (preventing creaming in the stomach) slowed gastric emptying, resulting in 12% higher gastric volume over time (P < 0.001), increased small bowel water content (SBWC) by 11% (P < 0.01), slowed appearance of the 13C label in the breath by 17% (P < 0.01), and reduced food intake by 9% (P < 0.05) compared with the Coarse treatment. The Fine+LBG treatment (smaller droplet size) slowed gastric emptying, resulting in 18% higher gastric volume (P < 0.001), increased SBWC content by 15% (P < 0.01), and significantly reduced food intake by 11% (P < 0.05, equivalent to an average of 411 kJ less energy consumed) compared with the Coarse+LBG treatment. These high-fat meals stimulated substantial increases in SBWC, which increased to a peak at 4 h at 568 mL (range: 150–854 mL;P < 0.01) for the Fine+LBG treatment.Conclusion: Manipulating intragastric stability and fat emulsion droplet size can influence human gastrointestinal physiology and food intake
Organisation structurale et moléculaire des lipides dans les aliments : impacts possibles sur leur digestion et leur assimilation par l’Homme
Lactobacillus gasseri SBT2055 suppresses fatty acid release through enlargement of fat emulsion size in vitro and promotes fecal fat excretion in healthy Japanese subjects
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