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    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

    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

    Transposition of the yeast retroviruslike element Ty3 is dependent on the cell cycle.

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    Host cell cycle genes provide important functions to retroviruses and retroviruslike elements. To define some of these functions, the cell cycle dependence of transposition of the yeast retroviruslike element Ty3 was examined. Ty3 is unique among retroviruslike elements because of the specificity of its integration, which occurs upstream of genes transcribed by RNA polymerase III. A physical assay for Ty3 transposition which takes advantage of this position-specific integration was developed. The assay uses PCR to amplify a product of Ty3 integration into a target plasmid that carries a modified tRNA gene. By using the GAL1 upstream activating sequence to regulate expression of Ty3, transposition was detected within one generation of cell growth after Ty3 transcription was initiated. This physical assay was used to show that Ty3 did not transpose when yeast cells were arrested in G1 during treatment with the mating pheromone alpha-factor. The restriction of transposition was not due to changes in transcription of either Ty3 or tRNA genes or to aspects of the mating pheromone response unrelated to cell cycle arrest. The block of the Ty3 life cycle was reversed when cells were released from G1 arrest. Examination of Ty3 intermediates during G1 arrest indicated that Ty3 viruslike particles were present but that reverse transcription of the Ty3 genomic RNA into double-stranded DNA had not occurred. In G1, the Ty3 life cycle is blocked after particle assembly but before the completion of reverse transcription

    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

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