1,720,955 research outputs found

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    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

    Inhibition of candidacidal activity of polymorphonuclear cells by alveolar macrophage-derived factor from lung cancer patients.

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    Culture supernatants of alveolar macrophages (AM) from lung cancer patients are able to inhibit the candidacidal activity of polymorphonuclear cells (PMN) in vitro. This phenomenon is ascribed to a factor secreted in the culture medium by unstimulated AM from tumor-bearing patients, but not from normal subjects. The inhibitor does not apparently affect the phagocytic activity of PMN, but the superoxide release during phagocytosis is significantly impaired when cells are pretreated with supernatants containing the factor. The secretion of the inhibitor seems to be restricted to the pulmonary compartment of lung cancer patients, since culture supernatants of peripheral blood monocytes (PBM) from the same subjects are not capable of depressing the candidacidal activity of PMN. The AM-derived factor is not inactivated after exposure to heat (60 degrees C) and when supernatants are analyzed by HPLC, the inhibitory activity is recovered in the fractions corresponding to a low molecular weight (800 D). In conclusion, AM from lung cancer patients are able to produce a factor capable of inhibiting the antimicrobial activity of PMN. This could account, at least in part, for the enhanced susceptibility to local infections observed in lung cancer patients

    Mechanism of intracellular candidacidal activity mediated by calcium ionophore in human alveolar macrophages.

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    In the present study, we investigated the effect of in vitro treatment with calcium ionophore (A23187) on candidacidal activity of human alveolar macrophages (AM) from normal subjects. In vitro incubation of AM with A23187 results in a significant dose-dependent enhancement of candidacidal activity. The availability of Ca2+ and Mg2+ ions in the culture medium is crucial for phagocytosis and killing to occur, but appears irrelevant for the binding between Candida albicans and AM. Enhancement of the killing effect mediated by A23187 does not correlate with increased phagocytic activity; in fact, the availability of ions is required for the phagocytic event, but an increase of cations does not correlate with enhancement of this activity. On the contrary, the augmentation of killing activity correlates with increased production of superoxide anion. Moreover, soluble material endowed with candidacidal activity has been extracted from cytoplasmic granules of AM both unstimulated and following A23187 treatment in vitro. Indeed, the granules extracted contain cationic proteases and, when isolated from stimulated cells, appear to be significantly more cytotoxic for C. albicans with respect to those obtained from unstimulated AM. In conclusion, the results reported here show that the phagocytic and killing events are ion dependent and the enhancement of intracellular candidacidal activity mediated by A23187 in AM is correlated with an augmented anti-Candida activity of cation-activated proteases

    Variations on the Author

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    “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

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    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

    Dispelling the Myths Behind First-author Citation Counts

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    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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    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
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