1,721,009 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
Marginal liver: case report of a successful OLT from an 84-year-old donor.
No full textThe consequence of good results obtained by OLT has been increasing discrepancy between the number of potential recipients awaiting transplantation and the number of available grafts. Many centres experienced a relaxation of the criteria in accepting livers. There is no unanimous agreement about what is a marginal liver, and there is no evidence of a clear limit to donor age.
Between June 1997 to December 1999, 94 OLT were performed at
our institution. Of these, 11 (11.7%) were realised using donors
older than 60 years (mean 66.8; range 60 to 84). We report the
outcome of a 40-year-old recipient affected by hepatocellular
carcinoma transplanted thanks to a 84-year-old donor
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
Split liver transplantation: need for arterial reconstruction in adult patients.
No full textSplit liver transplant technique was developed to improve the pediatric organ supply without affecting the adult donor pool. Moreover the introduction of the in situ split liver (ISSL) allowed to improve the quality of the liver grafts. The shortage of liver grafts for adult patients has urged to extend this technique to a full adult usage. Arterial reconstruction and related complications can be a major factor in morbidity and mortality after orthotopic liver transplantation (OLT) as they may cause graft failure, sepsis and biliary tract complications. Moreover, split liver transplantation is challenging, both at splitting time and at implantation time
Split liver transplantation in adult patients: hepatic and portal vein division and reconstruction.
No full textSplit liver transplant technique was developed to improve the pediatric organ supply without affecting the adult donor pool. Moreover the introduction of the in situ split liver (ISSL) grafting allowed to improve the quality of the liver grafts. The shortage of liver grafts for adult patients has urged to extend this technique to a full adult usage. The transition from whole liver grafting to segmental liver grafting urged technical improvement in venous reconstruction. Hepatic vein obstruction is a critical but rare vascular complication in end-to-end anastomoses between the inferior vena cava (IVC) of the recipient and the suprahepatic IVC of the whole graft liver. Between July 1997 and July 2000, 131 OLT were performed at our institution, 50 of them (38.2% of the global activity) using split grafts. Fifty ISSL procedures were performed either at our institution and the respective graft was then shipped to the sharing center, or the procedure was performed by us or with our assistance at the sharing center itself.Splitting procedures were performed in 50 heart-beating donors hemodinamically stable and eligible for ISSL. The ISSL took a mean time of 1 hours 50 minutes with a mean blood loss of 280 mL. The introduction of the ultrasound dissector significantly reduced blood loss and the operative time. We did not experience any thrombosis or stenosis of the vena cava; instead we experienced two cases of acute outflow block rescued with a side to side cavocavostomy. One recipient of a right hemiliver died 8 days after OLT for graft failure due to poor venous outflow. We did not experience stenosis or thrombosis of the portal vein. Split liver transplantation is an important option to improve the pool of cadaveric liver grafts but its feasibility is based on resolving challenging problems both at splitting and at implantation, being able to provide for unusual venous reconstruction in the majority of cases
Evaluation of hepatic glutathione changes in grafts from elderly donors during human liver transplantation.
No full textAppropriate 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
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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