1,721,145 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
Measurement of circulating concentrations of cardiac troponin i and T in healthy subjects: A tool for monitoring myocardial tissue renewal?
No full textThe increased analytical sensitivity of the new generation of methods for cardiac troponin I (cTnI) and T (cTnT) has demonstrated that measurable troponin is present in the blood of healthy adult subjects. These data are not in accordance with the prevailing opinion that any reliably detected increase in cardiac troponins should be considered abnormal and potentially caused by cardiac necrosis. The goal of the present review is to discuss the hypothesis that cardiac troponins can be released from cardiomyocytes, even in healthy adult subjects as a result of a process related to "physiological renewal" of the human myocardium and possibly enhanced by physical exercise or aging. The latest generation of high-sensitive cTnI and cTnT immunoassays are characterized by detection limits (DLs) as low as a few picograms. This clearly represents a greater increase in discrimination than that obtained by the most sophisticated cardiac imaging techniques that are commercially available at present. However, the critical question is whether high-sensitive troponin assays are clinically useful and in particular, whether some specific laboratory biomarkers (such as cTnI and cTnT) yield better diagnostic (or prognostic) accuracy and cost-effectiveness when compared with echocardiography in patients with cardiovascular disease. Only specific and well-designed clinical trials will answer this important question. © 2009 by Walter de Gruyter Berlin New York
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
Gonadogenesis in early developmental stages of Acipenser naccarii and influence of estrogen immersion on feminization
No full textGonadogenesis in early developmental stages of Acipenser naccarii and influence of estrogen immersion on feminization.
Abstract: Gonad development processes and the effects of a single 8-hour immersion treatment with 17-estradiol (E2, 400 g L-1) on sex differentiation in the Adriatic sturgeon, Acipenser naccarii, were investigated. After migration of germ cells, gonadal ridges appeared in 16- to 18-day old larvae and undifferentiated gonads in 55- to 60-day old larvae. Putative ovaries with notches in the germinal epithelium and presumed testes with smooth germinal epithelium appeared in 180- 185-day old juveniles. Ovaries with proliferating oogonia and early meiotic oocytes clusters were observed in 292-day old juveniles. Testes did not exhibit germ cell mitosis until 430 days of age. Developmental stages in E2-treated animals closely followed those of controls up to 430 days. The treatment significantly increased the percentage of ovaries when administered to embryos about 1.5 day before hatching, while did not significantly altered the normal 1/1 sex ratio when administered to 1.5-day old pre-larvae and 10-day old larvae. An increase of body weight and length was detected in embryo treated groups: it was related to the larger percentage of females, since in control females a higher specific growth rate for weight and length was detected. The results suggest that E2 did not act on gonad differentiation but rather on commitment of somatic cells involved in gonad morphogenesis. It is likely that in A. naccarii exogenous E2 administration may act through a feedback mechanism of self-supporting steroid production and that steroids are the physiological inducers of sex differentiation, as in most teleosts. The E2-immersion treatment, easier than time-consuming administration through food, could be a good approach to control sex differentiation and caviar production
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
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
Functional popliteal artery entrapment syndrome: A brief overview of literature based on graph theory
No full textN/
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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