1,720,968 research outputs found
Proximal versus distal protection: dissecting clinical trials
No full text: Carotid artery stenting (CAS) is a valid alternative to conventional carotid endarterectomy for treatment of carotid artery stenosis. Distal embolization of atherosclerotic debris causing cerebrovascular accidents during CAS has been the most significant concern limiting widespread application of CAS technology. A variety of embolic protection devices (EPDs) with different mechanism of action, have been designed to minimize the risk of major embolization causing stroke and their use is recommended by current guidelines. Two general types of EPDs are available: proximal protection devices (PPDs) and distal protection devices (DPDs). However, there is no convincing clinical evidence of the clinical superiority of one device over another. This review will examine the different types of available devices and also innovative devices and techniques, including strengths and weaknesses of each, and present the available evidence and rationale for their routine use during CAS
Mini-thoracotomy in redo mitral valve surgery: safety and efficacy of a standardized procedure
Full text linkBackground: Re-operative mitral valve surgery is sometimes burdened by a greater technical difficulty and a higher complications rate than the first operation. Minimally invasive cardiac surgery has become routine, and it could significantly reduce the surgical risk in redo surgery. The objective of our retrospective observational study is to assess the results of cardiac reoperations in patients with mitral valve disease approached trough a 5-7 cm right mini-thoracotomy. Methods: From February 2017 to December 2019, 65 patients underwent re-operative mitral valve surgery in our institution. Cardiopulmonary bypass (CPB) was started by cannulation of the femoral and jugular vein and femoral artery or alternatively right axillary artery. Patients enrolled had a mean age of 66.6±11.5 years. Patients were divided into three groups based on the procedure adopted: external aortic cross-clamp (EAC), EndoAortic balloon occlusion (EABO) and ventricular fibrillation (VF). Major complications were evaluated and compared with a propensity matched population of patients undergoing elective isolated mitral valve surgery via right minithoracotomy (MVS). Results: The average time between last operation and reoperation was 7.1±3.4 years. Fourteen patients (21%) underwent mitral valve repair and 51 patients (78%) underwent mitral valve replacement; 9 patients (14%) received tricuspid valve surgery. There was no statistically significant difference in CPB time between the groups. Seven patients (11%) had a postoperative renal failure, 5 patients (8%) underwent surgical reopening for bleeding; incidence of post-operative stroke and pace-maker implantation was 3% for both. No deaths were registered during in-hospital stay and at 30-days echocardiographic control all patients respect the criterions of device success according with MVARC. Propensity matched patients of group redo had a longer CPB time (100.8±42.7 versus 72.8±16.7 min, P<0.001) and cross-clamp time (71.9±30.7 versus 59±10.7 min, P<0.001) respect to first operation mitral valve surgery patients. Conclusions: Minimally invasive mitral valve redo surgery is a safe procedure. Less invasive techniques in redo surgery could minimize morbidity and mortality without prolonging the duration of CPB
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
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