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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

    Current role of CT in pediatric ophthalmology

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    In spite of the recent and substantial improvements in MR technique, some problems still exist relative to its applications in routine clinical exams in pediatric ophthalmology. The main problems are: inadequate MR equipment, long examination time, and MR inability to demonstrate intraocular calcifications. Ocular and orbital ultrasound (US) studies are highly operator-dependent, and US utility has been especially described in evaluating ocular, but not orbital, lesions. In order to verify the actual role of CT in pediatric ophthalmology, the CT scans of 58 children with ophthalmologic pathologies, performed over a 2-year period, were reviewed and compared with definitive diagnoses. Seven separate CT findings for each pathologic condition were independently analyzed and correlated with histology. In agreement with other CT series, optic nerve gliomas were invariably intraconal, whereas histiocytosis-X, Ewing's sarcoma, olfactory neuroblastoma (esthesioneuroblastoma), metastatic neuroblastoma and nephroblastoma were extra-conal. Rhabdomyosarcoma, principally extraconal, frequently involved the intraconal and preseptal spaces, with permeative destruction of the osseous orbit and frequent intra/extracranial spread. Orbital spread was mainly observed in vascular tumors. CT showed great accuracy in evaluating punctuate calcifications in retinoblastomas and in metastatic neuroblastomas, and bone fragments within a zone of destruction in histiocytosis-X. Various characteristics of CT attenuation values were observed in pathologic tissues, and high attenuation and marked contrast enhancement were particularly observed in metastatic neuroblastomas and rhabdomyosarcomas. In congenital orbital abnormalities and inflammatory diseases, CT readily detected ocular malformations (microphthalmos and colobomata).(ABSTRACT TRUNCATED AT 250 WORDS

    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
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