1,721,042 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Single stage repair of symptomatic type IV thoracoabdominal aortic and iliac aneurysm in Behçet's disease : case report
No full textA 50-year-old man with Behçet's disease (BD) diagnosed ten years previously, was submitted to emergency operation of two symptomatic type IV thoracoabdominal aortic and left common iliac aneurysms repair. Despite the rarity of vascular lesions in the course of BD, the uncommon clinical situation of double symptomatic aneurysms was successfully treated with surgical management that appears more difficult because of the inflammatory process associated with obliterative endoarteritis involving all periaortic tissues
Open aortic surgical repair for left hemi-arch stent-graft failure
No full textA surgical technique of endovascular graft explant through an open aortic approach for left hemi-arch stent-graft failure is described. Between January and April 2003, we surgically treated 3 patients previously submitted for stent grafts for isthmic aortic diseases. Two patients had atherosclerotic aneurysm and 1 had a false lumen reperfusion of subacute intramural hematoma. At 6 to 8 months computed tomographic scan follow-ups on all patients showed a rapid enlargement of aortic diameters due to type I endoleaks. The presence of an uncovered proximal stent in the parasubclavian aorta did not allow a simple aortic cross clamping; therefore we performed an open aortic procedure through a left posterolateral thoracotomy, using femoro-femoral bypass and mild hypothermic circulatory arrest. Selective antegrade cerebral perfusion was started within 3 to 5 minutes from aortotomy and graft removal. Left hemi-arch and descending thoracic aortic replacement was then performed with continuous cerebral perfusion. No surgical mortality was observed. Postoperative course was uneventful for neurologic, cardiac, respiratory, and renal complications. The 3-month follow-ups were event free. This approach, associated with rapid stent-graft explant and selective cerebral antegrade perfusion, appears to be a safe and effective surgical strategy for treating this new aortic pathology
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe 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
Acute type A aortic dissection and coarctation of aortic isthmus
No full textAcute type A aortic dissection and coarctation of the aorta is a rare associated disease. A case of two-stage repair is presented. Firstly the ascending aorta and the right hemi-arch was replaced using deep hypo-thermic circulatory arrest. Cardiopulmonary bypass was proximally instituted, in a patient with total aortic isthmus occlusion, using right axillary artery cannulation. Distally arterial perfusion was obtained cannulating the bilateral hypoplasic femoral arteries. Ten months later a left subclavian artery-descending thoracic aorta bypass was performed
Proximal pseudoaneurysm of ascending-abdominal aortic bypass
No full textProximal pseudoaneurysm of ascending-abdominal aortic bypass is an uncommon surgical disease. We report a repair of complete detachment of proximal anastomosis of the ascending-abdominal aortic bypass in a 68-year-old man that underwent surgery in 1988 for chronic descending thoracic aortic aneurysm treated with thromboesclusion technique. The clinical, diagnostic, and operative aspects are discussed
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
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