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    Incidence of apoptosis and transcript abundance in bovine follicular cells is associated with the quality of the enclosed oocyte

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    The close contact and interaction between the oocyte and the follicular environment influence the establishment of oocyte developmental competence. Moreover, it is assumed that apoptosis in the follicular cells has a beneficial influence on the developmental competence of oocytes. The aim of this study was to investigate whether bovine oocytes with varied developmental competence show differences in the degree of apoptosis and gene expression pattern in their surrounding follicular cells (cumulus and granulosa cells). Oocytes and follicular cells from follicles of 3 to 5 mm in diameter were grouped as brilliant cresyl blue (BCB)+ and BCB- based on glucose-6-phosphate dehydrogenase (G6PDH) activity in the ooplasm by BCB staining. In the follicular cells initial, early and late apoptotic events were assessed by analyzing caspase-3 activity, annexin-V and TUNEL, respectively. Global gene expression was investigated in immature oocytes and corresponding follicular cells. BCB+ oocytes resulted in a higher blastocyst rate (19.3%) compared to the BCB- group (7.4%, P < 0.05). Moreover, the analysis of apoptosis showed a higher caspase-3 activity in the follicular cells and an increased degree of late apoptotic events in granulosa cells in the BCB+ compared with the BCB- group. Additionally, the global gene expression profile revealed a total of 34 and 37 differentially expressed genes between BCB+ and BCB- cumulus cells and granulosa cells, respectively, whereas 207 genes showed an altered transcript abundance between BCB+ and BCB- oocytes. Among these, EIF3F, RARRES2, RNF34, ACTA1, GSTA1, EIF3A, VIM and CS gene transcripts were most highly enriched in the BCB+ oocytes, whereas OLFM1, LINGO1, ALDH1A3, PTHLH, BTN3A3, MRPS2 and PPM1K were most significantly reduced in these cells. Therefore, the follicular cells enclosing developmentally competent oocytes show a higher level of apoptosis and a different pattern of gene expression compared to follicular cells enclosing non-competent bovine oocytes

    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

    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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