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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
Fondamenti razionali per l'impiego dei condotti arteriosi nella chirurgia coronarica. Parte I: Evidenze anatomo-patologiche
No full textVariations 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
The effect of multiple blood conservation techniques on donor blood exposure in adult coronary and valve surgery performed with a membrane oxygenator: a multivariate analysis on 1310 patients
No full textThe object of the study was to retrospectively evaluate protective and risk factors for receiving donor blood products and red cell transfusions after coronary and valve surgery performed with a hollow-fiber oxygenator and with multiple blood-saving techniques. During the period of January 1991 to June 1993, 1310 patients underwent primary coronary and valve surgery using a hollow-fiber oxygenator at our institution; the mean age of this population was 61 ±10 years; 977 patients were men (74.6%). Of these patients, 73.5% (963/1310) underwent coronary, 21.5% (281/1310) valve, and 5% (66/1310) combined surgery. Two hundred seventy-six (21.1%) needed donor blood product transfusions, while 153 (11.7%) patients underwent red cell transfusions. Significant risk factors for homologous blood product exposure after multivariate logistic regression analysis were, in order of importance: (1) postoperative blood loss (O.R. = 1.0009 per mL, p = 0.0000); (2) cardiopulmonary bypass (CPB) time (O.R. = 1.008 per min, p = 0.0001); (3) age at intervention (O.R. = 1.031 per calendar year, p = 0.0026); and (4) reoperation for bleeding (O.R. = 1.71, p = 0.0078). Protective factors were: (1) male gender (O.R. = 0.56, p = 0.0000); (2) preoperative withdrawal of autologous blood (O.R. = 0.66, p = 0.0018); and (3) a preoperative hematocrit greater than 34% (O.R. = 0.76, p = 0.005). When considering risk factors only for donor red cell exposure, multivariate regression analysis identified the following risk factors: (1) reoperations for bleeding (O.R. = 2.04, p = 0.0002); (2) postoperative blood losses (O.R. = 1.0007 per mL, p = 0.0005); (3) CPB time (O.R. = 1.0075 per min, p = 0.0008); and (4) age at intervention (O.R. = 1.03 per calendar year, p = 0.0160). Protective factors were: (1) intraoperative “high-dose” aprotinin administration (O.R. = 0.61, p = 0.0024); and (2) preoperative donation if autologous blood (O.R. = 0.65, p = 0.0093); and (3) intraoperative withdrawal of autologous blood by phlebotomy (O.R. = 0.67, p = 0.0114). Applying multiple blood-saving techniques, coronary and valve procedures can now be performed with a low incidence of postoperative donor blood products and red cells exposures; autologous blood predonation and aprotinin administration were highly effective in reducing postoperative transfusion needs
Riflessi renorenali nel ratto determinati dalla stimolazione naturale dei chemorecettori renali
No full textIn vitro assessment of the vacuum-assisted venous dreinage (VAVD) system: risks and benefits
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
Aprotinin and deep hypothermic circulatory arrest: there are no benefits even when appropriate amounts of heparin are given
No full textTo evaluate retrospectively the effect of 'high-dose' aprotinin on blood losses, donor blood requirements and morbid events on patients undergoing ascending aorta and/or aortic arch procedures with the employ of deep hypothermic circulatory arrest (HCA)
Effetto eccitatorio degli inibitori dell'enzima di conversione sull'attività nervosa simpatica post-ganglionare efferente al rene nel ratto
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