1,720,962 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

    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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    Rat hindlimb unloading by tail suspension reduces osteoblast differentiation, induces IL-6 secretion, and increases bone resorption in ex vivo cultures.

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    In this research we utilized tail-suspended rats as an in vivo model for bone loss studies in order to investigate the effects of the tail suspension on the structure of the suspended bones and in ex vivo cultures the activities of trabecular osteoblasts, marrow-derived osteogenic cells, and osteoclasts obtained from treated animals, compared with untreated controls. After a 5-day hind limb unloading, trabecular thinning was already evidenced in the tibial primary spongiosa. In the secondary spongiosa, the bone formation activity was reduced whereas osteoclastic parameters were not yet altered. Bone marrow-derived osteogenic cells and differentiated osteoblasts from enzymatic digestion of posterior limb trabecular bone were prepared from 5 day tail-suspended rats and from normally loaded rats as controls. Cell morphology, alkaline phosphatase (ALPH) activity, production of mineral matrix, osteocalcin, and IL-6 secretion were evaluated in both cell populations. Tail suspension reduced the osteogenic potential of stromal marrow cells and of already differentiated osteoblasts. In fact, ALP positive colonies were significantly reduced in number and were smaller in size compared with controls and bone nodules formed in permissive conditions were also significantly fewer and smaller, whereas in cultures of cells from control conditions, large mineralizing nodules were formed. Osteocalcin secretion was not affected by unloading. Finally, IL-6 concentration was increased in marrow-derived cells from treated rats compared with controls. Primary cultures of osteoclasts were obtained from the nonadherent fraction of the bone marrow of the same animals. The number of TRAP positive cells in culture from tail-suspended rats was significantly increased, as well as bone resorption activity, measured as resorbed surfaces of a suitable synthetic hydroxyapatite, compared with controls. These data clearly suggest that skeletal unloading not only reduces the osteogenic potential of osteoblastic cells but induces an increased osteoclastogenesis and osteoclast activity in ex vivo cultures. They also indicate for the first time that a possible mediator responsible for the increased osteoclastogenesis could be represented by the IL-6 whose secretion by bone marrow cells was significantly enhanced by unloading

    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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