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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
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
koamabayili/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
Modulation du transport du Ca²+ et du Na+ cytosolique et nucléaire par la taurine dans les cellules ventriculaires cardiaques
No full textTaurine has been reported to produce (i) a positive inotropic effect in heart muscle, (ii) beneficial effects in treatment of congestive heart failure and (iii) protective effects against Ca2+ overload. The objective of this work was to determine the short and long-term effect of normal physiological concentration of taurine on [Ca2+]i and [Na+]i of ventricular heart cells, and to determine whether long-term exposure to normal concentration of taurine ( 1mM) block and/or prevent Ca2+ overload in heart cells induced by sustained depolarization of the cell membrane.
Using the fura-2 Ca2+ fluorescence microfluorometry and imaging techniques as well as fluo-3 and Na+-Green 3-D confocal microscopy measurement of free Ca2+ and Na+ respectively, short-term exposure to normal physiological concentration of taurine (1 mM) had no effect on the steady-state basal total [Ca2+]i and [Na+]i in isolated ventricular heart cells. However, exposure to relatively high concentrations of taurine (10-80 mM) induced a significant concentration-dependent sustained increase of the resting steady-state basal total [Ca2+]i and [Na+]i of ventricular heart cells. Pretreatment with β-alanine, a blocker of taurine- Na+ cotransporter, was found to block taurine-induced dose-dependent increase in [Ca2+]i in heart cells. Also a low concentration of the Na+/ Ca2+-exchanger blocker, CBDBMB (an amiloride derivative), was found to attenuate the increase in total [Ca2+]i induced by short-term treatment with taurine. Thus, the increase of basal total [Na+]i by short-term treatment with taurine could be due to Na+ entry through the taurine- Na+ cotransporter and the increase in the basal steady-state [Ca2+]i could then be due to an increase in [Na+]i which in tum favors sarcolemrnal Ca2+ influx through the Na+/ Ca2+-exchanger. Thus, taurine at relatively high concentration may exert a positive inotropic effect by such mechanism. Using the same techniques, it was found that the increase of basal total intracellular Ca2+·and Na+ levels by short-term treatment with high concentration of taurine ( ≥ 5mM) is mainly nuclear. The increase of basal nuclear sustained Na+ by taurine could be due to possible presence of a taurine- Na+ cotransporter on the nuclear membrane whereas the increase of nuclear sustained Ca2+ could be due to cytosolic Ca2+ buffering by the nucleus.
Long-term exposure of heart cells to normal physiological concentration of taurine ( 1 mM) was found to decrease both cytosolic and nuclear sustained Ca2+ as well as nuclear Na+ without affecting cytosolic Na+. Moreover, long-term exposure to taurine was found to prevent nuclear increase of Ca2+ induced by permanent depolarization of heart cells with high [K+]o . This preventive effect of taurine on nuclear Ca2+ overload was associated with an increase of both cytosolic and nuclear Na+. Thus, the effect of long-term exposure to taurine on intranuclear Ca2+ overload in heart cells seems to be mediated via stimulation ofsarcolemma and nuclear Ca2+ outflow through the Na+/ Ca2+-exchanger. The fact that taurine failed to block the observed sustained elevation of nuclear Ca2+ pre-induced by sustained long-term depolarization of the membrane suggests that this amino acid possesses only a preventive effect on nuclear Ca2+ overload. [Symboles non conformes]Il est rapporté que Ia taurine produit (i) un effet inotrope positif dans le muscle cardiaque, (ii) des effets bénéfiques dans le traitement de l'insuffisance cardiaque et (iii) des effets protecteurs contre la surcharge du Ca2+. L'objectif de cette étude est de déterminer l'effet à long-terme et à court-terme de la taurine a une concentration physiologique normale sur [Ca2+]i et [Na+]i sur des cellules ventriculaires cardiaques et de déterminer si le traitement à long-terme avec une concentration normale de taurine (1mM) bloque et/ou empêche Ia surcharge calcique induite par une dépolarisation soutenue de la membrane cellulaire. En utilisant les techniques de microfluometrie et d'imagerie avec la sonde calcique fura-2 et la méthode de mesure en 3-D a l'aide de Ia microscopie confocale et les sondes fluo-3 et Na+-Green pour le Ca2+ et le Na+ respectivement, la présence de taurine à une concentration physiologique normale a court-terme, n'a pas d'effet sur le niveau basal total du [Ca2+]i et [Na+]i chez les cellules cardiaques ventriculaires isolées. Cependant, I'ajout de Ia taurine à des concentrations relativement élevées ( 10-80 mM) a induit une augmentation soutenue significative concentration-dépendente du niveau basal total du [Ca2+]i et [Na+]i des les cellules cardiaques. Le pré-traitement avec de la β-alanine, un bloqueur du co-transporteur taurine- Na+, a bloqué l'augmentation du [Ca2+]i induite par Jes concentrations croissantes de taurine dans les cellules cardiaques. De même, une faible concentration du bloqueur de l'échangeur Na+/ Ca2+ , CBDBMB (dérivé de l'amiloride), a atténué I' augmentation totale du [Ca2+]i induite par le traitement avec la taurine a court-terme. L'augmentation du niveau basal total du [Na+]i par le traitement à court-terme avec la taurine peut être due à l'entrée du Na+ à travers le co-transporteur taurine- Na+ et l'augmentation du niveau basal du [Ca2+]i peut être due alors à l'augmentation du [Na+]i qui favorise l'influx calcique à travers le sarcolemme via l'échangeur Na+/ Ca2+ . La taurine exerce alors un effet inotrope positif par un mécanisme semblable. En utilisant les mêmes techniques, il a été démontré que I'élévation du niveau basal total intracellulaire du Ca2+ et Na+ par le traitement à court-terme avec des concentrations élevées de taurine ( ≥ 5mM) est principalement nucléaire. L'augmentation soutenue du niveau basal nucléaire de Na+ par la taurine peut être due à Ia présence possible du co-transporteur taurine- Na+ sur la membrane nucléaire, tandis que l'augmentation soutenue du Ca2+ nucléaire peut être due à l'effet tampon calcique du noyau.
Le traitement des cellules cardiaques a long-terme avec une concentration physiologique normale de taurine a diminué le Ca2+ cytosolique et nucléaire ainsi que le Na+ nucléaire sans affecter le Na+ cytosolique. De plus, le traitement à long-terme avec la taurine a empêché l'augmentation nucléaire du Ca2+ induite par la dépolarisation soutenue des cellules cardiaques avec une concentration élevée de [K+]o. Cet effet préventif de la taurine sur la surcharge calcique nucléaire était associé à l'augmentation du Na+ cytosolique et nucléaire. L' effet du traitement à long-terme avec la taurine sur la surcharge du Ca2+ intranucleaire dans les cellules cardiaques se fait suite à la sortie du Ca2+ à travers la membrane nucléaire et le sarcolemme via la stimulation de I' échangeur Na+/ Ca2+ Le fait que la taurine n'a pas bloqué l'élévation soutenue du Ca2+ nucléaire observée pré-induite par la dépolarisation soutenue de la membrane à long-terme suggère que cet acide aminé possède uniquement un effet préventif sur la surcharge du Ca2+ nucléaire. [Symboles non conformes
Calcium transport via membrane-bound proteins across the gastrointestinal epithelium of rats
No full textAuthor-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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