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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

    Prevalence, Predictors, and Severity of Lean Nonalcoholic Fatty Liver Disease in Patients Living With Human Immunodeficiency Virus

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    The burden of non-alcoholic fatty liver disease (NAFLD) is growing in people with HIV. NAFLD is associated with obesity, however it can occur in normoweight (lean) patients. We aimed to investigate lean NAFLD in HIV-infected patients

    Diagnosis of liver fibrosis in ageing patients with HIV at risk for non-alcoholic fatty liver disease in Italy and Canada: assessment of a two-tier pathway

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    Background: Since the introduction of effective antiretroviral therapy, liver-related mortality has increased ten-fold in ageing people with HIV. This trend is driven by ageing-related metabolic conditions that cause non-alcoholic fatty liver disease (NAFLD), which affects 35-65% of people with HIV. Clinically significant (stage 2-4) liver fibrosis develops in over 15% of people with HIV who have NAFLD. Strategies are needed to identify people with HIV at risk for significant liver fibrosis and reduce cirrhosis-related complications. Non-invasive tests to diagnose liver fibrosis include ultrasound-based transient elastography and serum biomarkers. Transient elastography is a feasible tool to assess liver fibrosis, but it is not largely accessible in HIV clinics. We aimed to determine whether a two-tier care pathway with assessment of simple serum biomarkers for fibrosis as first tier could reduce the need for the specialist transient elastography test (second tier). Methods: Patients were consecutively identified through a clinical programme for liver disease in people with HIV in Canada and Italy. We applied a two-tier care pathway to three prospective cohorts of people with HIV at risk for NAFLD, defined as those with elevated liver transaminases, body mass index (BMI) of 25 or greater, or diabetes. Patients with alcohol abuse or coinfection with hepatitis B or C viruses were excluded. Five simple serum biomarkers of fibrosis, based on liver transaminases, platelets, and BMI (fibrosis-4 index [FIB-4], BARD [BMI, AST to ALT ratio, diabetes] score, NAFLD fibrosis score, AST to ALT ratio, and AST-to-platelet ratio index [APRI]) were applied as a first-tier assessment to exclude significant liver fibrosis. All patients then received transient elastography. We assessed the decrease in referral for transient elastography that would have occurred based on biomarker assessment and discordance between high transient elastography (≥7·1 kPa), indicating significant liver fibrosis, and low serum fibrosis biomarkers (FIB-4 <1·3, BARD score 0-1, NAFLD fibrosis score less than -1·455, AST to ALT ratio <0·8, and APRI <0·5). We also assessed independent factors associated with that discordance by multivariable logistic regression analysis. Findings: We included 1202 people with HIV at risk for NAFLD (mean age 51·2 years [SD 10·1], 914 [76%] male and 288 [24%] female, mean HIV duration 16·3 years [SE 9·7], mean BMI 26·5 Kg/m2 [SD 4·5]; prevalence of diabetes 49·5%). 222 (18·5%) of these participants had significant liver fibrosis according to transient elastography. Assessment of simple fibrosis biomarkers would have decreased transient elastography referrals between 22·5% (BARD score) and 82·4% (APRI). Discordance rate ranged from 3·9% (NAFLD fibrosis score) to 11·1% (APRI). After adjustment for age, sex, presence of diabetes, level of HDL cholesterol, and CD4 cell count, BMI (odds ratio 1·12, 95% CI 1·07-1·17) and triglyceride level (1·25, 1·08-1·46) were independent predictors of discordance for low APRI and high transient elastography. Interpretation: Use of a two-tier pathway to identify liver fibrosis in ageing people with HIV at risk for NAFLD could reduce transient elastography examinations by a substantial proportion, reducing costs and helping to optimise use of resources in HIV care

    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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    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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