1,721,017 research outputs found
Taraji P. Henson, Clinton Carbon, c1990s.
No full textActress, Howard University alumna Taraji P. Henson (R), and Howard University professor Clinton Carbon, c1990s.https://dh.howard.edu/africana_photos/1015/thumbnail.jp
Taraji P. Henson at the 2005 (78th) Academy Awards ceremony
No full textTaraji P. Henson performs nominated song "It's Hard Out Here for a Pimp" (from HUSTLE & FLOW) at the 2005 (78th) Academy Awards ceremony. 35mm color negative
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Differential metabolism of exogenous and endogenous arachidonic acid in human neutrophils
No full textLeukotrienes can be produced by cooperative interactions between cells in which, for example, arachidonate derived from one cell is oxidized to leukotriene A4 (LTA4) by another and this can then be exported for conversion to LTB4 or cysteinyl leukotrienes (cys-LTs) by yet another. Neutrophils do not contain LTC4 synthase but are known to cooperate with endothelial cells or platelets (which do have this enzyme) to generate cys- LTs. Stimulation of human neutrophils perfusing isolated rabbit hearts resulted in production of cys-LTs, whereas these were not seen with perfused hearts alone or isolated neutrophils. In addition, the stimulated, neutrophil-perfused hearts generated much greater amounts of total LTA4 products, suggesting that the hearts were supplying arachidonate to the neutrophils and, in addition, that this externally derived arachidonate was preferentially used for exported LTA4 that could be metabolized to cys-LTs by the coronary endothelium. Stable isotope-labeled arachidonate and electrospray tandem mass spectrometry were used to differentially follow metabolism of exogenous and endogenous arachidonate. Isolated, adherent neutrophils at low concentrations (to minimize transcellular metabolism between them) were shown to generate higher proportions of nonenzymatic LTA4 products from exogenous arachidonate (deuterium-labeled) than from endogenous (unlabeled) sources. The endogenous arachidonate, on the other hand, was preferentially used for conversion to LTB4 by the LTA4 hydrolase. This result was not because of saturation of the LTA4 hydrolase, because it occurred at widely differing concentrations of exogenous arachidonate. Finally, in the presence of platelets (which contain LTC4 synthase), the LTA4 synthesized from exogenous deuterium-labeled arachidonate was converted to cys-LTs to a greater degree than that from endogenous sources. These experiments suggest that exogenous arachidonate is preferentially converted to LTA4 for export (not intracellular conversion) and raises the likelihood that there are different intracellular pathways for arachidonate metabolism
Variations on the Author
Full text link“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
Full text linkWe 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
Full text linkWe 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
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