1,722,784 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

    Regulation of Psc-Su(z)2 genes in drosophila melanogaster

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    The Psc and Su(z)2 genes belong to the Polycomb Group (PcG) and Psc itself is one of the core components of the PRC1 repressive complex and genetic evidence suggests that it is autoregulated by PcG mechanisms. Recently, the Psc-Su(z)2 region was also found to contain several putative Polycomb Response Elements that bind PcG proteins while the entire region is enriched for H3K27me3. Current model of PcG mechanism is all-or- none silencing paradigm derived from its role in homeotic gene regulation. However, it is likely that PcG regulation at many other target genes functions by down-regulating rather than silencing expression. This is certainly the case for PcG genes like Psc and Su(z)2. To understand how PcG mechanisms down-regulate a target gene, the nature of the PcG binding sites in the Psc-Su(z)2 region and their repressive effects were analyzed, using reporter gene construct. There are at least two functional PREs that can silence a reporter gene in a PcG-dependent manner and one of them can also show anti-silencing activity, depending on the chromosomal context. In addition, we found a down-regulation module in the vicinity of Psc promoter, whose effect is insensitive to the dosage of PcG genes. Probably, several different regulatory elements might be cooperative to down-regulate Psc-Su(z)2 genes by PcG mechanism. I have also generated small deletions that remove one such binding peak. Deletion of one of the Psc-Su(z)2 PREs increases the expression level of Psc and Su(z)2 by 2-3 fold at late embryonic stage. Perhaps the increased expression of PSC can partially compensate by binding to the other PREs in the Psc-Su(z)2 locus. On the contrary, the expressions of CG13323 and CG13324 genes behind of the PRE are decreased by 20 to 50 fold during entire embryonic stages. Also, the chromatin IP experiment showed that the loss of this fragment extends the domain of H3K27me3 around 10kb further, to a region that includes both of CG13323 and CG13324 transcripts. So, the fragment removed in both deletions may not possess only PRE but also a transcriptional enhancer for downstream genes or boundary element to block the PcG silencing.Ph.D.Includes bibliographical references (p. 92-99)by Sung-Yeon Par

    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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