Search results for "Wax"
showing 10 items of 107 documents
Sesquiterpene lactones, waxes and volatile compounds from Artemisia herba-alba subspecies Valentina
1979
Abstract The structures of two sesquiterpene lactones isolated from Artemisia herba-alba subsp. valentina have been determined by spectroscopic methods. One of these was dihydroreynosin, the other was a new compound assigned the name torrentin. The chemical compositions of a wax and a hydrocarbon fraction from the essential oil have also been investigated.
In-mouth mechanism leading to the perception of fat in humans: from detection to preferences. The particular role of saliva
2013
In humans, the perception of fat in food is a complex process involving many sensory modalities (texture, aromaand flavour). Themouth is the first place in which the process of digestion begins. During this process, a bolus is formed in which saliva is significantly incorporated. For solids and semi-solid fatty matrices, saliva and the shear forces applied during mastication contribute to their breakdown and/or destabilisation in emulsified systems. These mechanisms are often dependent on the fat content of the food and thus play an important role in not only the perception of texture but also the release of compounds responsible for the flavour of “fat”. In addition, saliva is directly inv…
Évolution du stress gélif et idéotypes de pois d'hiver dans le contexte de changement climatique, à une échelle régionale.
2017
11 pages; International audience; Pea (Pisum sativum L.) is an important crop in temperate regions for its high seed protein concentration that is particularly sensitive to abiotic stresses. The abrupt temperature increase known as the “1987/1988 temperature regime shift” that occurs over Europe is questioning how winter pea will perform in the changing climate. This study assessed the winter frost damage evolution along from 1961 to 2015 in Burgundy-Franche-Comté by using: (1) daily observed and gridded regional temperature data and (2) a validated crop winter frost stress model calibrated for pea. This study shows a global decrease of the frost stress nevertheless resulting from a subtle …
Determination of pesticide residues in honey bees, pollen and beeswax: assessing pesticide hazard in spanish apiaries
2020
Pollinator decline is an emerging worldwide problem with serious repercussions on agriculture and environment. Around one third of human food relies on insect pollination, and most of the flowering plants need pollinators to survive. Honey bee is the main pollinator in environments where anthropogenic pressure has reduced the number of native pollinators, like urban, rural and agricultural areas. The main cause of beekeeping crisis is parasite Varroa destructor and secondary infections associated with the mite. Pesticide contamination and nutritional deficiencies, combined with the parasite, can act synergistically and reduce survival of bee colonies. Honey bees patrol extensive areas when …
Structural Characterization of Surfactant-Coated Bimetallic Cobalt/Nickel Nanoclusters by XPS, EXAFS, WAXS, and SAXS
2011
Cobalt nickel bimetallic nanoparticles were synthesized by changing the sequence of the chemical reduction of Co(II) and Ni(II) ions confined in the core of bis(2-ethylhexyl)phosphate (2)., and Ni(DEHP)(2). The reduction was carried out by mixing, sequentially or contemporaneously, fixed amounts of n-heptane solution of Co(DEHP)2 and Ni(DEHP)2 micelles with a solution of sodium borohydride in ethanol at a fixed (reductant)/(total metal) molar ratio. This procedure involves the rapid formation of surfactant-coated nanoparticles, indicated as Co/Ni (Co after Ni), Ni/Co (Ni after Co), and Co + Ni (simultaneous), followed by their slow separation as nanostructures embedded in a sodium bis(2-eth…
The Development and Precision of a Custom-Made Skitester
2021
In the sport of cross-country skiing, equipment has a direct influence on results. Ski teams do extensive testing of different ski base grinds and products on a yearly basis. To achieve reliable results, the quality of methods used for testing skis needs to be taken in to account in addition to factors including the physical characteristics of testing personnel and changes in weather conditions. The aim of this study was to introduce a custom-made skitester, that was developed for testing skis on real snow, in laboratory conditions, and to evaluate its precision. The current skitester is capable of glide testing both classic and skate skis as well as kick simulation for the testing of grip …
Mécanisme d’absorption intestinale des acides gras à longue chaîne : rôle émergent du CD36
2012
International audience; Excessive lipid intake, associated with a qualitative imbalance, favors the development of obesity and associated diseases. Among the organs involved in lipid homeostasis, the small intestine remains the most poorly known although it is responsible for the lipid bioavailability and largely contributes to the regulation of postprandial hypertriglyceridemia. The mechanism of long chain fatty acid (LCFA) intestinal absorption is not totally elucidated. The synthesis of recent literature indicates that the intestine is able to adapt its absorption capacity to the fat content of the diet. This adaptation takes place through a fat-coordinated induction of LBP and apolipopr…
Complémentarité et équilibre de l’apport alimentaire en protéines et en lipides
2003
The nature and level of dietary protein is liable to influence cholesterol and essential fatty acid (EFA) metabolism. Dietary vegetable protein, particularly the undigested fraction, decreases intestinal cholesterol absorption, increases the faecal excretion of steroids, and enhances the catabolism of cholesterol-carrying lipoproteins by increasing the activity or number of LDL receptors. However, the hypocholesterolemic effect of protein may be due to the presence of non-protein components and hence the purity degree of the selected protein, and the concomitant addition or not of cholesterol. Dietary proteins with different amino acid composition may modulate the secretion of hormones (e.g…
Rôle des lipides dans la régulation du comportement alimentaire
2008
Obesity constitutes a major public health problem for the 21 st Century, with its epidemic spread worldwide, particularly in children. The overconsumption of fatty foods greatly contributes to this phenomenon. Rodents and humans display a spontaneous preference for lipid-rich foods. But why are lipids so attractive? What are the molecular mechanisms involved? The purpose of this mini review is to explore few basic questions raised by recent data providing evidences on the relationships between dietary lipids and feeding behavior.
The role of hemostatic devices in neurosurgery. A systematic review.
2021
Hemostasis represents a fundamental step in every surgical procedure. During neurosurgical procedures, proper and robust hemostasis into confined spaces can significantly reduce the odds of perioperative complications. Over the decades, multiple methods have been applied, and several medical devices have been developed to promote and guarantee proper hemostasis. This study presents a systematic review of the most used intraoperative hemostatic methods and devices in neurosurgery. Insightful research was performed on the PubMed database according to the PRISMA guidelines. This comprehensive review of scientific literature represents a synoptic panel where the most used intraoperative hemosta…