2,804 research outputs found

    Effects of induced subacute ruminal acidosis on milk fat content and milk fatty acid profile

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    Two lactating dairy cows fitted with a rumen cannula received successively diets containing 0%, 20%, 34% and again 0% of wheat on a dry matter basis. After 5, 10 and 11 days, ruminal pH was measured between 8:00 and 16:00 hours, and milk was analysed for fat content and fatty acid profile. Diets with 20% and 34% wheat induced a marginal and a severe subacute ruminal acidosis respectively. After 11 days, diets with wheat strongly reduced the milk yield and milk fat content, increased the proportions of C8:0 to C13:0 even- or odd-chain fatty acids, C18:2 n-6 and C18:3 n-3 fatty acids but decreased the proportions of C18:0 and cis-9 C18:1 fatty acids. Wheat also increased the proportions of trans-5 to trans-10 C18:1, the latter exhibiting a 10-fold increase with 34% of wheat compared with value during the initial 0% wheat period. There was also an increase of trans-10, cis-12 C18:2 fatty acid and a decrease of trans-11 to trans-16 C18:1 fatty acids. The evolution during adaptation or after return to a 0% wheat diet was rapid for pH but much slower for the fatty acid profile. The mean ruminal pH was closely related to milk fat content, the proportion of odd-chain fatty acids (linear relationship) and the ratio of trans-10 C18:1/trans-11 C18:1 (nonlinear relationship). Such changes in fatty acid profile suggested a possible use for non-invasive diagnosis of subacute ruminal acidosis

    Effect of platinum on the growth rate of the oxide scale formed on cast nickel aluminide intermetallic alloys

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    Thermo-Gravimetric Analysis ( TGA) and Scanning Electron M icroscopy ( SEM ) data of the initial stages of oxidation of Ni50Al50 and Ni40Pt10Al50 alloys of low and high sulfur content at 900◦ C and 1100◦ C are reported. The results show that the addition of Pt promotes the growth of the transient θ- Al2O3 oxide scale. This effect is particularly sensitive in the initial stages of oxidation at 1100◦ C where Pt considerably increases the total mass gain. It is attenuated in the presence of a high sulfur content in the alloy, indicating a competitive effect of Pt and S on the segregation of Al. The slower θ-to- α transition observed in the presence of Pt leads to an extended lifetime of the θ phase layer, which is proposed to be benecial to the relaxation of the stresses created by the growth of α-Al2O3

    L'ORGANISATION EN TENSION ENTRE ROUTINE ET CREATION : UN AUTRE REGARD SUR L'INSTRUMENTATION DE GESTION

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    Les organisations sont écartelées entre des logiques contradictoires : il leur faut créer pour " rester dans la course ", mais il ne peut y avoir de création durable sans coexistence avec des routines. Créer signifie rompre avec des schémas préétablis, gérer sa propre peur de l'inconnu et gérer les conflits que la rupture créative ne marquera pas de générer avec les tenants de l'orthodoxie sécurisante. Nous tenterons d'éclairer cette tension dialectique entre création et routine par un détour philosophique, puis grâce à la complémentarité des regards psychologique et sociologique.création; innovation; routine; peur

    Statistical parsing of morphologically rich languages (SPMRL): what, how and whither

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    The term Morphologically Rich Languages (MRLs) refers to languages in which significant information concerning syntactic units and relations is expressed at word-level. There is ample evidence that the application of readily available statistical parsing models to such languages is susceptible to serious performance degradation. The first workshop on statistical parsing of MRLs hosts a variety of contributions which show that despite language-specific idiosyncrasies, the problems associated with parsing MRLs cut across languages and parsing frameworks. In this paper we review the current state-of-affairs with respect to parsing MRLs and point out central challenges. We synthesize the contributions of researchers working on parsing Arabic, Basque, French, German, Hebrew, Hindi and Korean to point out shared solutions across languages. The overarching analysis suggests itself as a source of directions for future investigations

    Modèles éducatifs et attitudes des jeunes : une exploration comparative internationale

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    Alors qu’une solide tradition de sociologie du curriculum s’est développée dans les pays anglo-saxons, peu de recherches empiriques concernent, en France, les contenus d’enseignement. L’article présente les résultats d’une recherche examinant comment, dans une variété de pays, se structurent les curricula, et explore si des liens peuvent être établis avec les attitudes observées par ailleurs chez les élèves. Il met en évidence trois grands modèles curriculaires idéal-typiques : à des systèmes éducatifs fondés sur une « éducation totale » s’opposent deux modèles fondés soit sur les matières académiques, soit sur la vie professionnelle. Ces différenciations de contenus d’enseignement s’inscrivent dans des organisations pédagogiques et sociales au sein de l’école différentes. L’hypothèse de relations entre, d’un côté, les attitudes des élèves et, de l’autre, ces modèles curriculaires et les organisations sociales qui les accompagnent au sein de l’école est confortée partiellement, même si ce résultat est évidemment contingent à la construction des variables d’attitudes dans la base de données utilisée (PISA). Mais de manière plus générale, c’est la possibilité d’évaluer les « effets » de l’éducation qui est questionnée, notamment dans le domaine des attitudes.Whereas sociology of the curriculum is an established area of study in English-speaking countries, little empirical research on educational content has been done in France. The article presents the results of a study of how curriculums are structured in a variety of countries and explores whether connections can be established between curriculum type and observed student attitudes. Inspired by Bernstein’s work, it brings to light three major ideal-typical curriculum models: “total education” systems as opposed to an academic studies model, and another model where the aim is to prepare students for occupational life. These differences in educational content are consistent with differences in the way schools organize teaching and social relations. The hypothesis that connections exist between student attitudes on one hand, curriculum model and type of social organization within the school on the other is partially confirmed, though this result is obviously contingent on how attitude variables were constructed in the PISA database used. At a more general level, we call into question whether it is actually possible to assess the “effects” of education, especially in the area of attitudes

    Efficient trajectories computing using inversibilities properties

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    A time-consuming problem encountered both in system diagnosis and planning is that of computing trajectories over a behavioral model. In order to improve the efficiency of this task, there is currently a great interest in using model-checking techniques developed within the area of computer aided verification. In this paper, we propose to represent the system as automata and we define a property called inversibility. This property is used to improve the efficiency of the search algorithm computing trajectories. We present two study cases in diagnosis and planning domains where this approach gives satisfactory results
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