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    First-line steroid treatment for spontaneous intracranial hypotension

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    Background: Spontaneous intracranial hypotension (SIH) is a syndrome characterized by low cerebrospinal fluid (CSF) pressure and postural headaches, and affects 1 per 20,000 individuals every year. Case report: We report an otherwise healthy 38-year-old man admitted to the hospital with orthostatic headache that developed 48 h after a short-haul flight during which he sustained a neck injury due to turbulence. Neurological examination, blood analysis and computed tomography scan performed at the emergency service were normal. Brain and spine magnetic resonance imaging (MRI) showed diffuse pachymeningeal enhancement and contrast medium egress from the subarachnoid space into the epidural space at the level of C2. The patient was treated with bed rest, hydration and 1 mg/kg/day oral prednisone for 5 days, with a gradual withdrawal in the following 7 days. Complete symptomatic relief was observed after 16 days, with resolution of the pathological findings on brain and spinal MRI after 1 month, except for localized pachymeningeal enhancement. Clinical relief was maintained over time until last follow-up visit 9 months later. Conclusion: Successful conservative treatment barely exceeds one quarter of cases of SIH. The clinical benefits of steroids may result from several mechanisms of action, for example, improving brain oedema and inflammation, determining fluid retention, and facilitating reabsorption of the CSF from extradural space. Notwithstanding that epidural blood patch remains the most successful treatment for SIH, future studies should explore the effectiveness of steroids as first-line therapy in addition to the most commonly suggested measures of bed rest and hydration

    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
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