1,720,959 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 desogestrel-containing oral contraceptives on vascular reactivity and catecholamine levels.
No full textThe modifications induced by new oral contraceptives (OC) on blood pressure, great vessel vascular reactivity by color Doppler, and catecholamine levels were investigated. Young healthy women not taking OC (n = 22; controls) or receiving, for > or = 6 months, OC containing desogestrel with either 30 micrograms (n = 14) or 20 micrograms of EE (n = 8) were enrolled. Blood pressure measured at rest in supine position was similar between controls and OC users. The pulsatility index (PI), an indirect index of resistance to blood flow, of axillary artery was significantly higher (p < 0.05) in 30 micrograms than in 20 micrograms EE OC users or controls. A similar trend, albeit not significant, was observed for the internal carotid artery PI. Norepinephrine (p < 0.01) and dopamine (p < 0.05) but not epinephrine levels, were lower in 30 micrograms EE OC users than in 20 micrograms EE OC users or controls. Thus, both 20 micrograms and 30 micrograms EE OC had no negative effect on blood pressure, but the 30 micrograms EE OC tended to increase great vessel resistance to blood flow, independently of catecholamine levels.The effects on blood pressure of oral contraceptives (OCs) containing desogestrel plus either 20 or 30 mcg of ethinyl estradiol were investigated in 22 women who had been using one of these formulations for 6 months or more and 22 matched controls. There were no significant differences between both groups of cases and controls in blood pressure measured at rest in supine position. However, subtle differences were recorded in vascular reactivity, as evaluated by color Doppler ultrasound investigation. Compared to controls and users of OCs containing 20 mcg of ethinyl estradiol, cases taking OCs consisting of 30 mcg of ethinyl estradiol had a significantly higher pulsatility index in the axillary artery, indicating increased vessel resistance to blood flow. A similar, although not significant, trend was found in the internal carotid artery pulsatility index. On the other hand, catecholamine (dopamine and norepinephrine) levels were reduced by both OCs in a dose-dependent manner. Overall, these findings suggest that third-generation OCs, especially those containing 20 mcg of ethinyl estradiol, exert minimal effects on circulatory parameters. It is hypothesized that the cardiovascular effects of catecholamine reduction are antagonized by other mechanisms, among them the stimulus on the renin-angiotensin system
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
Potentially beneficial cardiovascular effects of melatonin administration in women.
No full textThe cardiovascular effects induced by the daytime administration of melatonin (1 mg) were compared to those of placebo in 12 young women. In order to eliminate cardiovascular effects due to fluctuating endogenous sex steroids, all women were taking a fixed dose of monophasic contraceptive pill. In comparison to placebo, the administration of melatonin reduced, within 90 min, the pulsatility index of the internal carotid artery, evaluated by color Doppler ultrasound (P < 0.01), as well as both systolic and diastolic blood pressure evaluated in supine position (P < 0.01). Supine catecholamine levels were not significantly modified, but norepinephrine levels evaluated after 5 min of standing position were significantly reduced (P < 0.02). These data suggest that in women the administration of 1 mg of melatonin may exert beneficial effects on blood vessels
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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