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Methamphetamine use is an independent predictor of poor outcome after aneurysmal subarachnoid hemorrhage
No full textBACKGROUND: Clinical outcomes of methamphetamine users with aneurysmal subarachnoid hemorrhage (aSAH) are unknown. OBJECTIVE: To analyze differences in presentation, in-hospital morbidity, and outcomes between methamphetamine users and non-users. METHODS: All 472 patients included in the Barrow Ruptured Aneurysm Trial from 2003 to 2007 were reviewed. Patients with 1- and 3-year follow-up were included in this analysis (n=398). Methamphetamine users were identified as patients who provided a history of methamphetamine use on admission or tested positive on urine toxicology testing. Methamphetamine users were compared with non-users using univariate analysis. Outcomes were then analyzed using multivariate logistic regression models for demographic characteristics, medical comorbidities, radiographic and clinical presentation, and vasospasm. RESULTS: Thirty-one patients (7.8%) were identified as methamphetamine users in this cohort. Methamphetamine users were younger than non-users (mean age 42.8 vs 55 years, p\u3c0.001). In multivariate logistic regression models, methamphetamine use was an independent predictor of poor Glasgow Outcome Scale score at both 1 year (OR=5.02; 95% CI 1.03 to 24.48; p\u3c0.05) and 3 years (OR=7.18; 95% CI 1.73 to 29.87; p=0.007). Other independent predictors in this model included older age, clinical vasospasm, diabetes, and aneurysm size. Cocaine and tobacco use were not significantly associated with poor outcome in our cohort. Methamphetamine use was not significantly associated with vasospasm, higher Fisher or Hunt and Hess grade, or intraparenchymal hemorrhage/intraventricular hemorrhage. CONCLUSIONS: Methamphetamine users have significantly worse outcomes at 1 and 3 years following aSAH. Further analysis is necessary to understand the pathological response associated with methamphetamine use in this setting
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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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