1,720,963 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
The bowel cleansing for colonoscopy. A randomized trial comparing three methods.
INTRODUCTION:
Colonoscopy is the procedure of choice for the detection and ablation of small lesions o the colonic mucosa. A proper bowel cleansing is mandatory. So far several regimens have been proposed but rather none has shown a clear-cut advantage over the others. Aim of this study was to compare cleansing ability and patients' compliance of three oral regimens.
PATIENTS AND METHODS:
Two-hundred and seventy-three patients were block randomised into three groups. Group A (92 patients) received tablets containing senna 12 mg and Magnesium Sulphate 15 mg the day before colonoscopy. Group B (98 patients) received a Polyethylene Glycol-based solution of two litres plus 4 tablets of Bisacodyl the day before the exam. Group C (83 patients) received Sodium Phosphate 40 milliliters the day before and the day of colonoscopy. Results of 265 patients were available for the analysis. Eight patients were excluded because inability to follow prescription. The lower incidence of constipation in group C was not significant. The other parameters were homogeneously distributed in the three groups.
RESULTS:
The 79 patients of the group C achieved a better bowel cleansing as compared with the 90 of group A (p = 0.0003) and the 96 of group B (p = 0.034). Constipated patients had a significantly better cleansing with Sodium Phosphate preparation compared with senna plus Magnesium Sulphate (p = 0.017), but not significantly better compared with Golytely solution. Compliance and rate of total colonoscopy performed were not statistically different in the three groups.
CONCLUSIONS:
Sodium Phosphate solution gave better bowel preparation, with the same compliance, than either senna or Polyethylene solution. In constipated patients Sodium Phosphate showed good efficacy resulting in good cleansing rates similar to that of non-constipated patients. The poor results obtained by Polyethylene were related to the little amount of solution taken even if associated to Bisacodyl
Variations on the Author
“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
We 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
We 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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