1,720,976 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Etude des propriétés biophysiques et mécano-sensorielles des podosomes
No full textLes podosomes sont des microstructures du cytosquelette cellulaire constituées d'un cœur dense d'actine filamenteuse entouré à leurs bases de protéines qui établissent un lien étroit avec la matrice extracellulaire à la face ventrale des cellules. Contrairement aux adhérences cellulaires " classiques ", ces structures sont très dynamiques et ont également la particularité de pouvoir localement dégrader la matrice extracellulaire. Les podosomes sont spécifiques à quelques types cellulaires pour la plupart très mobiles, principalement issus du lignage myéloïde dont les macrophages, cellules clés de l'immunité innée. Si de nombreuses études ont été menées dans le but de caractériser l'architecture et la régulation de la formation des podosomes, de nombreuses questions demeurent sur la fonction exacte de ces structures. En effet, si le caractère très dynamique des podosomes semble participer à la perception de l'environnement par les cellules, les études sur les processus mécano-sensoriels de ces structures sont encore très sporadiques. Dans ce contexte, l'objectif de ma thèse s'est alors inscrit dans une démarche exploratoire pour tenter d'approfondir les caractéristiques mécano-sensorielles et biophysiques des podosomes des macrophages humains dans un contexte d'étude in vitro par l'utilisation combinée d'approches complémentaires comme (i) la Microscopie à Force Atomique, (ii) la microstructuration de protéines de matrices par impression par micro-contact (iii) la fabrication de matrices à rigidités modulables (iv) la mise en œuvre de substrats très fins déformables suspendus. L'ensemble de mes travaux de thèse a permis l'étude des podosomes à l'échelle nanométrique dans des cellules vivantes, ce qui a permis de révéler (i) que la hauteur des podosomes est constante quelle que soit la physico-chimie du substrat, (ii) que ces structures sont capables d'exercer sur le substrat une contrainte normale oscillante et périodique dépendante de la contraction des complexes acto-myosine et de la polymérisation d'actine, et (iii) que ces structures présentent une dynamique de rigidité périodique étroitement liée à la dynamique des contraintes que ces structures génèrent sur le substrat et qui est également dépendante de la rigidité de la matrice.Podosomes are particular sub-cellular F-actin rich structures, composed of a dense actin-core surrounded at it base by numerous proteins that establish a close contact with the extracellular matrix on the ventral face of the cell. Unlike "classical" adhesive structures, podosomes are very dynamic and are able to locally degrade the extracellular matrix. These structures are specifically found in very motile cells, which mainly belong to the myeloid cell lineage, including macrophages, which are key cells of the innate immunity. Despite numerous studies that aimed to decipher podosome architecture and signaling pathways that regulates their formation, several questions remains about the exact role of these structures. Indeed, if the dynamic behavior of podosome seems to participate in the probing activity of the cells for analyzing their surrounding environment, studies of podosome mechanosensory processes is still sporadic. In this context, the purpose of my PhD was an exploratory research in order to decipher mechanosensory and biophysical properties of podosomes in human macrophages in vitro. Thus several complementary approaches were combined such as: (i) Atomic Force Microscopy, (i) micro-contact printing of matrix proteins, (iii) fabrication of matrices with various stiffness, and (iv) the use of a thin compliant suspended substrate. Finally my work enabled to explore podosomes at a nanometer-scale level in living cells and shaded light on several aspects as: (i) the height of podosomes is constant independently of the physicochemical properties of the substrate, (ii) theses structures are able to exert a normal, oscillating and periodic strain on the substrate related to acto-myosin complexes contraction and actin-polymerization activity, (iv) these structures have periodic stiffness oscillations closely related to the periodic strain they exert on the substrate, which are modulated by the stiffness of the substrate
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
Deciphering Podosome Physical Properties in Human Macrophage by Atomic Force Microscopy
No full textkoamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe 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.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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