1,009 research outputs found

    Comparison between S. T. radar and in situ balloon measurements

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    A campaign for simultaneous in situ and remote observation of both troposphere and stratosphere took place near Aire-sur-l'Adour (in southeastern France) on May 4, 1984. The aim of this campaign was a better understanding of the physics of radar echoes. The backscattered signal obtained with a stratosphere-troposphere radar both at the vertical and 15 deg. off vertical is compared with the velocity and temperature measurements made in the same region (about 10 km north of the radar site) by balloon-borne ionic anenometers and temperature sensors. In situ measurements clearly indicate that the temperature fluctuations are not always consistent with the standard turbulent theory. Nevertheless, the assumptions generally made (isotropy and turbulent field in k) and the classical formulation so derived for radar reflectivity are able to reproduce the shape of the radar return power profiles in oblique directions. Another significant result is the confirmation of the role played by the atmospheric stratification in the vertical echo power. It is important to develop these simultaneous in situ and remote experiments for a better description of the dynamical and thermal structure of the atmosphere and for a better understanding of the mechanisms governing clear-air radar reflectivity

    Étude rĂ©trospective des animaux prĂ©sentant une double population d'hĂ©maties mise en Ă©vidence par le Sysmex XT-2000iV

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    Les objectifs de ce travail Ă©taient de dĂ©terminer la frĂ©quence des Ă©rythrogrammes bifides, leurs causes et leur pronostic chez l’animal. Au travers de cette Ă©tude rĂ©trospective nous avons pu dĂ©terminer qu’une telle anomalie n’a Ă©tĂ© observĂ©e que dans 9 cas parmi prĂšs de 20 000 hĂ©mogrammes rĂ©alisĂ©s au laboratoire central des cliniques. Elle est prĂ©sente dans la majoritĂ© des cas (8 cas sur 9) chez des animaux prĂ©sentant une anĂ©mie et traduit dans la majoritĂ© des cas une dysĂ©rythropoĂŻĂšse. Dans notre Ă©tude, les chats sont l’espĂšce la plus reprĂ©sentĂ©e

    Protein-polyphenol reactions: 1. Nutritional and metabolic consequences of the reaction between oxidized caffeic acid and the lysine residues of casein

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    1. Studies were made on the lysine content of casein reacted with caffeic acid oxidized aerobically under alkaline conditions or enzymically with tyrosinase (EC 1.14.18.1). 2. Loss of fluorodinitrobenzene (FDNB)-reactive lysine was rapid at pH 10 and increased with time and the temperature of the reaction, with concentration of caffeic acid and with the oxygenation of the mixture. In presence of the enzyme mushroom tyrosinase, maximum reduction of reactive lysine occurred at pH 7 and was dependent on the reaction time and on the concentration of caffeic acid. 3. Reaction of α-formyl-L-[U- 14C]lysine with caffeic acid at pH 10 showed the rapid formation of five reaction products which appeared to polymerize gradually as the reaction progressed. 4. The nutritionally available lysine content of the casein-caffeic acid mixtures, as assayed with rats, was reduced after both alkaline and enzymic reactions, as were faecal digestibility, net protein ratio and net protein utilization. Biological value however was not reduced. 5. In metabolic studies using goat milk casein labelled with L-[3H]lysine and reacted with caffeic acid in the same way, the lysine-caffeoquinone reaction products were not absorbed by the rat but were excreted directly in the faeces. 6. The importance of the reaction of proteins with caffeoquinone and chlorogenoquinone (formed by the oxidation of caffeic and chlorogenic acids respectively) is discussed in relation to the production of sunflower protein, leaf protein and other vegetable-protein concentrate

    Bases anatomiques et fonctionnelles de la reproduction chez le zébu (Bos indicus)

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    Le rapport prĂ©sentĂ© par l'auteur a Ă©tĂ© Ă©laborĂ© Ă  partir d'observations publiĂ©es par les zootechniciens qui s'occupent de la reproduction du zĂ©bu dans les aires d'extension de cette espĂšce et de travaux effectuĂ©s au Laboratoire d'Anatomie, Histologie et Embryologie de l'Ecole Inter-Etats des Sciences et MĂ©decine VĂ©tĂ©rinaire de l'UniversitĂ© de Dakar. Dans un chapitre consacrĂ© Ă  l'anatomie, les particularitĂ©s du tractus gĂ©nital du mĂąle et de la femelle sont notĂ©es. L'aspect fonctionnel du problĂšme fait l'objet du second chapitre dans lequel sont rapportĂ©es d'abord les donnĂ©es zootechniques ayant trait Ă  la durĂ©e du cycle oestral, Ă  l'oestrus, aux Ăąges auxquels se produisent la pubertĂ©, la premiĂšre saillie fĂ©conde et le premier vĂȘlage, Ă  la durĂ©e de la gestation, Ă  l'intervalle qui sĂ©pare deux vĂȘlages consĂ©cutifs, au rythme annuel des fĂ©condations et aux facteurs saisonniers capables d'influencer la reproduction. L'Ă©tude histo-pathologique a permis de mettre en Ă©vidence des phases d'anoestrus chez les femelles vides et trois gĂ©nĂ©rations successives de corps gestatifs sur les femelles pleines. Chez les mĂąles, l'auteur signale des pĂ©riodes caractĂ©risĂ©es par des images de repos des glandes annexes du tractus gĂ©nita

    Le FLS : un concept en question

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    On trouvera dans cet article une prĂ©sentation rapide du concept de français langue seconde (FLS), avec sa dĂ©finition et son positionnement par rapport aux concepts voisins de français langue maternelle (FLM) et de français langue Ă©trangĂšre (FLE), puis une discussion da la question du français langue seconde vis-Ă -vis du français pour migrants. On essaiera enfin de rĂ©pondre Ă  ceux qui s’interrogent sur l’utilitĂ© mĂȘme d’un tel concept en didactique du FLE.One will find in this article, a quick overview of the concept of french as a second language (FSL), with that term s definition and its position vis-Ă -vis the closely related concepts of french as a mother tongue (FMT) and french as a foreign language (FFL), followed by a discussion of the issue of french as a second language versus that of french for immigrants. Lastly, the author endeavours to reply to those who raise questions as to the very use of such a concept in the didactics of french as a foreign language

    Film extrusion of sunflower protein isolate

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    Film extrusion of sunflower protein isolate (SFPI) was studied. The influence of die temperature (85 to 160°C), water and glycerol contents were investigated through appearance, mechanical and thermo-mechanical properties and swelling behavior in water of films. It was demonstrated that highest temperature, well above SFPI denaturation temperature in the compound, highest glycerol content (70 parts for 100 parts of SFPI) and medium water content (20 parts for 100 parts of SFPI) gave the most regular and smoothest film (as seen on SEM micrographs). Its ultimate tensile strength, Young’s modulus and strain at break were respectively: 3.2 MPa, 17.7 MPa and 73%. Soaked in water, its swelling was about 186% w/w but the film was quiet insoluble. Effect of temperature and plasticizer content were discussed in relation to the kinetic of SFPI denaturation. These first results are very promising for the development of biodegradable protein-based films

    Génie des procédés d'agglomération de poudres alimentaires (éléments de phénoménologie des apports d'eau et d'énergie mécanique)

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    Le procédé d'agglomération humide trouve des applications dans des secteurs industriels d'importance (e.g. agroalimentaire, pharmaceutique, génie civil, etc.) et s'appuie encore fortement sur le savoir-faire des opérateurs. Ce travail porte sur l'étude des contributions des apports hydriques et mécaniques à l'agglomération humide d'une poudre réactive (transformation de la semoule de blé en grains de couscous). Une approche découplée des apports d'eau et d'énergie mécanique est proposée. L'apport d'eau est étudié par la modélisation de l'influence des paramÚtres formulation et procédé de l'atomisation liquide sur la taille des gouttes pulvérisées. Les apports d'énergie mécanique sont étudiés à l'aide d'un équipement modÚle de malaxage. La répartition des contraintes verticales dans le milieu granulaire à l'état statique est identifiée via une "cartographie 2D des isocontraintes". Le comportement de la poudre au malaxage est étudié au cours du déplacement de la pale dans le malaxeur modÚle, par l'analyse des champs de vitesses des particules (obtenus par vélocimétrie par images de particules), et par la mesure des contraintes verticales au niveau de la pale. Une étude de la sthénique et de la cinématique des écoulements granulaires permet d'identifier des longueurs caractéristiques impliquées dans le comportement du milieu granulaire à l'état statique et sous sollicitation mécanique. L'étude couplée des apports hydriques et mécaniques est réalisée par suivi des dynamiques d'agglomération humide dans un malaxeur à pale. Elles sont décrites par des mesures en continu de la consommation énergétique et des mesures in situ des spectres d'absorption proche infra-rouge.The wet agglomeration process presents large applications in different industrial fields (e.g. food, pharmaceutics, civil engineering, etc.) and is still mainly based on technical know-how and empiricism of operators. This thesis work investigates the contributions of water and mechanical energy inputs to the wet agglomeration of a reactive powder, in the particular case of the transformation of durum wheat semolina in couscous grains. A uncoupled approach of both water and mechanical energy inputs is carried out. The water addition is studied through a modelisation of the influence of operating and formulation parameters of the liquid atomization process on the droplet size. Mechanical energy inputs are studied using a model experimental mixing equipment. Vertical stress distribution in the granular bed in static conditions is identified thanks to the establishment of a "2D iso-stress cartography". The granular medium behaviour under mechanical solicitation is studied during the blade motion in the model mixing equipment thanks to the analysis of granular flows and velocity fields (obtained by particle image velocimetry) and to vertical stress measurements directly on the blade. A sthenic and kinematic study of granular flows allows to identify characteristic lengths involved in the granular medium behaviour under mechanical solicitation. The coupled study of water and mechanical inputs is conducted by following in-line the wet agglomeration dynamics in a pilot mixing device using energetical consumption measurements as well as in situ acquiring of near infrared absorption spectra.MONTPELLIER-SupAgro La Gaillarde (341722306) / SudocSudocFranceF

    Les ganglions lymphatiques du zébu (Bos indicus). 2e partie : les lymphocentres du membre pelvien, du bassin, de l'abdomen et du thorax

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