1,721,010 research outputs found
Patient selection and anatomical considerations for zone 0 endovascular aneurysm arch repair
No full textEndovascular aortic arch repair has been widely used in select patients who are considered high risk for open surgical repair and have suitable anatomy. The anatomical challenges of placement of stent-grafts in the ascending aorta are many, including the curved configuration, short landing zone, proximity to the aortic valve and coronary arteries and need to incorporate the supra-aortic trunks. Stent-graft designs with fenestrations and/or directional branches are applicable to patients who have suitable landing zones in the aorta and supra-aortic trunks, adequate access and absence of significant atheromatous debris. These devices include single and multibranch concepts, which are used in combination or not with cervical debranching procedures. This article summarizes the most commonly used anatomical criterion with currently utilized arch branch stent-grafts
Commentary: Investigating and Predicting the Fate of Infrapopliteal Arterial Disease After Endovascular Treatment
No full textIn the August 2020 issue of the JEVT, Shammas et al1 highlighted a crucial point regarding the value of imaging in the treatment of infrapopliteal arterial occlusive disease. The authors compared angiography to intravascular ultrasound (IVUS) imaging in the evaluation of infrapopliteal vessel diameter and the presence and severity of dissections after balloon dilation alone or atherectomy followed by balloon dilation. The findings of their study are of outmost importance since technical details are crucial to success in a challenging vascular district. It is clear that angiography, as a diagnostic tool, is largely inadequate to provide all the necessary information for evaluating
both preoperative conditions and treatment outcome. Too many aspects cannot be evaluated by simple contrast
imaging, that is, hemodynamic pattern, 3-dimensional distribution of the lesion, and the condition of the arterial wall.
Moreover, to characterize any lesion, angiography should be performed in a variety of projections, which has a series of drawbacks. First of all, the amount of contrast medium would increase significantly, with consequences on renal
function, which is typically already impaired in atherosclerotic patients. Also, in some projections the target arterial
segment may be hidden by bone margin or other arteries. Finally, the hemodynamic aspect cannot be evaluated.2
Up to now, no clear benefit of endovascular techniques has been demonstrated over surgical revascularization in
infrainguinal disease.3,4 Plain balloon angioplasty, primary stenting, subintimal angioplasty, atherectomy, bailout stenting, drug-coated balloon (DCB) angioplasty, and so on, have been advocated as the method of choice in treating lower limb occlusive disease without reaching a consensus.5,6 The Shammas study1 focused on infrapopliteal treatment, which is still a particularly challenging field in peripheral revascularization and is associated with poor results
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
No full textWe 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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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