1,721,046 research outputs found
Causes of ischemic stroke in patients with atrial fibrillation
Objective: Atrial fibrillation (AF) is the most common cardiac arrhythmia affecting 1% of the adult population. However, ischemic strokes in patients with AF can be triggered by alternative mechanisms, especially in high-risk patients with additional vascular risk factors. In some patients, atherothrombotic mechanisms may cause stroke, and AF may be incidental or a symptom of atherosclerotic disease. In this case, it may be difficult to distinguish cardioembolic stroke from stroke due to large artery atherosclerosis. The aim of this study was to determine the causes of non-cardioembolic ischemic stroke in patients with non-valvular AF and to determine the risk factors for craniocervical atherosclerotic stenosis.Materials and Methods: This study identified risk factors for craniocervical atherosclerotic stenosis in patients followed up at the Uludag University Faculty of Medicine Department of Neurology with a diagnosis of ischemic stroke and non-valvular AF. In this study, 180 patients who were followed up with a diagnosis of non-valvular AF and acute ischemic stroke between January 1st, 2019 - March 1st 2020, in Uludag University Faculty of Medicine Department of Neurology, were retrospectively included.Results: In this study, the non-cardiac stroke rate was 20% in patients with non-valvular AF who had acute ischemic stroke. Ischemic stroke due to large vessel atherosclerosis was found in 14.4% of these patients, and 9.5% of all patients with AF were stented. When dermographic features, clinical features, and risk factors were analyzed for craniocervical atherosclerotic stenosis, a significant statistical result was obtained with male sex (p=0.020) and smoking (p<0.001).Conclusion: Stroke is a heterogeneous group of diseases caused by many complex mechanisms. Prevention of stroke recurrence is possible by starting effective treatment early. The presence of critical artery stenosis in a patient with acute ischemic stroke with AF causes stroke recurrence and this relapse cannot be prevented by anticoagulant treatment. Angiographic evidence also revealed ethnic and racial differences in patients with acute ischemic stroke. Therefore, more precise information can be obtained through prospective studies in our population
Going Beyond Counting First Authors in Author Co-citation Analysis
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
“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
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
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
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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