1,720,973 research outputs found
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
Double-orifice mitral valve in an eight-year-old boy
No full textThe case is described of an eight-year-old boy who required an operation for moderate mitral regurgitation due to a double-orifice mitral valve (DOMV). The DOMV, which was clearly demonstrated by transthoracic echocardiography, had a central fibrous bridge. Mitral valve repair using a 5/0 Prolene suture placed at the level of the superior commissure of each hole to stabilize the valve, and ring annuloplasty with Edwards Physio ring, was successfully performed. Intraoperative real-time transesophageal echocardiography showed the repaired DOMV to be without regurgitation or stenosis
Surgical Management of Intramyocardial Left Anterior Descending Artery
No full textAn intramyocardial left anterior descending artery can be found in up to 30% of patients undergoing coronary artery bypass graft procedures. We review the various techniques available to identify an intramyocardial left anterior descending artery
Giant Intrathoracic Schwannoma of the left vagus nerve presenting as atrial fibrillation
No full textPosterior mediastinal tumors are not infrequent, and among them neurogenic masses and schwannomas are the most common histological variety. They are benign, initially asymptomatic tumors and later become symptomatic due to the mass effect. Surgical excision is the preferred therapy and the approach can be evaluated according to the dimensions of the lesion. We report the case of a giant schwannoma, originating from the left vagus nerve, in a middle-aged woman whose symptoms were exertion-induced dyspnoea and atrial fibrillation
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
The Ross Operation In Neonates: The Best Choice?
No full textThe Ross Operation In Neonates: The Best Choice?
Stefano Congiu1, Sergio De salvatore2, Antonio Segreto2, Subbarayalu Balaji1, Chiusaroli Alessandro2, Federico Bizzarri2.
1Leeds Children Hospital, Leeds, United Kingdom, 2Università di Roma la Sapienza, Latina, Italy.
OBJECTIVE:
The Ross procedure was first described in 1967 for the treatment of aortic valve disease in adults. This procedure has been
lastly applied to neonates and infants expecially for severe left ventricular outflow tract obstruction (LVOTO) and severe aortic
valve disease. The potential for growth and the proven durability make the autograft an ideal aortic valve substitute.
METHODS:
5 neonates less than 30 days of age underwent a Ross procedure. The median weight was 3.2 kg. Three patients had a LVOTO
with different degrees of endomiocardial fibroelastosis. Two of them had a severe aortic regurgitation with dysplastic aortic valve
after aortic valvuloplasty. Three neonates required with a bovine yugular valve conduit and two of them a aortic homograft for
the reconstruction of the RVOT.
RESULTS:
There were no death with complete recovery of the left ventricular function in all cases. The autograft only showed trivial aortic
insufficiency with no residual LVOTO on Doppler echocardiography. The telediastolic volume increased to more than 20 ml/m2
and telediastolic pressure decreased to normal values before discharged from the hospital. The median hospital stay was 16
days without complications.
All the patients are free of operation or complications with a follow-up of 5 years.
CONCLUSIONS:
There were no death with complete recovery of the left ventricular function in all cases. The autograft only showed trivial aortic
insufficiency with no residual LVOTO on Doppler echocardiography. The telediastolic volume increased to more than 20 ml/m2
and telediastolic pressure decreased to normal values before discharged from the hospital. The median hospital stay was 16
days without complications.
All the patients are free of operation or complications with a follow-up of 5 years
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