1,720,955 research outputs found
Development of new oral dosage forms for colon-specifie drug delivery system
Les travaux décrits dans ce mémoire sont consacrés à la synthèse, à la caractérisation physico-chimique et à la
dégradation enzymatique de nouveaux excipients à base d'un polysaccharide d'origine naturelle, le dextran . Ces
excipients peuvent servir d'enrobage ou d'agent matriciels pour la réalisation des formes pharmaceutiques orales
à libération colique spécifique des principes actifs. A cette fin , deux stratégies principales de synthèses. ont été réalisées sur le dextran pour le rendre hydrophobe. La première est fondée sur l'estérification des fonctions hydroxyles du dextran pour préparer trois familles des esters de dextran (acétates, propionates ou butyrates) avec trois dégrée de substitutions (1, 2 et 3). La seconde voie de synthèse permet d'obtenir trois failles de dextran copolymères à blocs (di, tri et tétra blocs copolymères) par polymérisation radicalaire en émulsion d'un ou plusieurs monomères acryliques sur le bloc du dextrans. Les résultats avantageux des études in vitro de la libération de théophylline à partir de comprimés enrobés individuellement avec différentes types du dextrans
copolymères à blocs permettent de constater les potentielles utilisations de .ces dextrans copolymères à blocs pour délivrer des formes pharmaceutiques orales dans le côlon.The work described in this manuscript deals with the synthesis, the enzymatic degradation and the physical chemistry characterization of new excipients based on a natural polysaccharide, dextran. These excipients can
serve coating or agent matrix for the realization of oral pharmaceutical forms at colon-specifie release of the
active ingredients. To this end, two main strategies for syntheses were performed on dextran to make it hydrophobie. The first is based on the esterification of hydroxyl groups of dextran to prepare three families of dextran esters (acetate, propionate and butyrate) with three Degree of substitution (1 , 2 and 3). The second strategy allows to obtain three types of dextran block copolymers (di, tri and tetra-block copolymers) by free radical emulsion polymerization of one or more acrylic monomers (MA, MMA and MAA) on the block of dextrans. The beneficial results of in vitro release of theophyllin from tablets coated individually with different types of dextran block copolymers were allowed to determine the potential uses of dextran block copolymers to deliver oral dosage forms in the colon
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Mise au point de nouvelles formulations pharmaceutiques orales à délivrance ciblée de principes actifs au niveau du côlon
Les travaux décrits dans ce mémoire sont consacrés à la synthèse, à la caractérisation physico-chimique et à la dégradation enzymatique de nouveaux excipients à base d'un polysaccharide d'origine naturelle, le dextran . Ces excipients peuvent servir d'enrobage ou d'agent matriciels pour la réalisation des formes pharmaceutIques orales à libération colique spécifique des principes actifs. A cette fin , deux stratégies principales de synthèses. ont été ont été réalisées sur le dextran pour le rendre hydrophobe. La première est fondée sur l'esterificatlon des fonctions hydroxyles du dextran pour préparer trois familles des esters de dextran (acétates, propionates ou butyrates) avec trois dégrée de substitutions (1, 2 et 3). La seconde voie de synthèse permet d'obtenir trois failles de dextran copolymères à blocs (di, tri et tétra blocs copolymères) par polymérisation radicalaire en émulsion d'un ou plusieurs monomères acryliques sur le bloc du dextrans. Les résultats avantageux des études in vitro de la libération de théophylline à partir de comprimés enrobés individuellement avec différentes types du dextrans copolymères à blocs permettent de constater les potentielles utilisations de .ces dextrans copolymères à blocs pour délivrer des formes pharmaceutiques orales dans le côlon.The work described in this manuscript deals with the synthesis, the enzymatic degradation and the physicalchemistry characterization of new excipients based on a natural polysaccharide, dextran. These excipients can serve coating or agent matrix for the realization of oral pharmaceutical forms at colon-specifie release of the active ingredients. To this end, two main strategies for syntheses were performed on dextran to make it hydrophobie. The first is based on the esterification of hydroxyl groups of dextran to prepare three families of dextran esters (acetate, propionate and butyrate) with three Degree of substitution (1 , 2 and 3). The second strategy allows to obtain three types of dextran block copolymers (di, tri and tetra-block copolymers) by freeradical emulsion polymerization of one or more acrylic monomers (MA, MMA and MAA) on the block of dextrans. The beneficial results of in vitro release of theophyllin from tablets coated individually with different types of dextran block copolymers were allowed to determine the potential uses of dextran block copolymers to deliver oral dosage forms in the colon.STRASBOURG-Sc. et Techniques (674822102) / SudocSudocFranceF
Dispelling the Myths Behind First-author Citation Counts
We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
Author-wise bibliometric analysis based on entropy.</p
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