1,720,976 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
EFFECT OF AGING ON CIRCADIAN-RHYTHM OF ATRIAL-NATRIURETIC-PEPTIDE, PLASMA-RENIN ACTIVITY, AND PLASMA-ALDOSTERONE
No full textAtrial natriuretic peptide (ANP) shows a nychtohemeral fluctuation and an age-related trend. The aim of this study was to explore the circadian rhythm of ANP as a function of age. Circadian rhythms of plasma renin activity (PRA), aldosterone (PA), and cortisol (PC) were explored as well. Twenty clinically healthy subjects, 10 young (20-25 yrs) and 10 elderly (65-75 yrs), were investigated, while recumbent, after synchronization to light-dark regimen and meal timing. Blood samples for RIA tests were collected six times during the 24-hr span. The chronobiologic analysis in young subjects demonstrated a significant circadian rhythm for all the investigated variables with an acrophase-timing located at 16.48 for ANP, 4.44 for PRA, 5.32 for PA, and 7.12 for PC. In elderly subjects we documented an important increase of 24-hr mean plasma levels but not a statistically significant circadian rhythm for ANP, and a decrease in mean value of PRA which maintained, however, a significant periodic 24-hr oscillation in parallel with PA and PC. The results in young subjects reinforce the concept that ANP plays physiologically an inhibitory role on the phasic secretion of renin. The lack of the circadian rhythm for ANP along with the divergent changes in ANP and PRA 24-hr mean concentration of elderly subjects both suggest that ANP exerts with advancing age only a counter regulatory role on the tonic rather than the phasic release of renin
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
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 circadian rhythm of atrial natriuretic peptide, vasoactive intestinal peptide, beta-endorphin and cortisol in healthy young and elderly subjects.
No full textAtrial natriuretic peptide, vasoactive intestinal peptide, beta-endorphin and cortisol are humoral variables characterized by a 24-h periodicity. We evaluated the circadian rhythm of these peptides and hormones in healthy subjects who were young (between 20-25 years) or elderly (between 65-75 years). All were on controlled diets. Blood samples were collected six times during a 24-h period (at 06.00, 08.00, 12.00, 18.00, 20.00 and 24.00 h) beginning 8-h after start of recumbency. The time-related data were analysed by the Cosinor method in order to validate the circadian rhythm and to quantify rhythmometric parameters which included the midline estimate of rhythm (mesor). In contrast to the young subjects, Cosinor analysis failed to reveal a significant circadian rhythm in elderly subjects, for plasma cortisol. In elderly subjects oscillation (mesor) of atrial nutriuretic peptide was higher, while that of vasoactive intestinal peptide and beta-endorphins was lower. The results suggest changes in the physiological secretion of these three peptides in healthy elderly subjects
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
- …
