1,720,987 research outputs found
Contribution of oxygen-dependent mechanisms to vascular responses of exercise in young and older men: the role of prostaglandins and adenosine
Full text linkPrevious work suggests vasodilating prostaglandins (PGs) are released during isometric handgrip exercise in an O-dependent manner in young men. This project investigates their contribution to the exercise hyperaemia of isometric and rhythmic handgrip contraction performed by healthy, recreationally-active young and older men. Hyperoxia (40% O), aspirin, and their combination equally attenuated exercise and post-exercise hyperaemia, and venous efflux of PGE and PGI in both age groups: efflux of these PGs was not attenuated with age, but their contribution to the hyperaemic response was. Further, the release of COX products evoked reflex vasoconstriction in an O-dependent manner. Moreover, 40% O, aspirin, and their combination equally inhibited the exercise-evoked vasoconstriction in both age groups. However, both the exercise-evoked attenuation in perfusion of resting skeletal muscles and the contribution of COX products were attenuated with age. Additional experiments showed that adenosine contributes to the hyperaemia of electrically evoked isometric twitch contractions in an O-dependent manner; adenosine may contribute to the increase in the concentrations of vasodilating PGs. Importantly, unlike 60% and 100% O, 40% O did not attenuate acetylcholine-evoked endothelium-dependent dilatation in either age group, supporting the argument that the effect of 40% O during exercise is independent of hyperoxia-related oxidative stress
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
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
BS26 Electronic cigarettes adversely affect endothelial health and attenute brachial artery flow mediated dilation
No full textIntroduction Tobacco cigarette smoking is a predominant risk factor for cardiovascular disease and a leading preventable cause of death. Electronic Cigarette (EC) use has increased significantly in recent years. However, EC have been shown to increase oxidative stress. A low endothelium-dependent flow mediated dilation (FMD) signifies endothelial dysfunction and is an independent predictor of future cardiovascular morbidity and mortality. Herein we tested the hypothesis that EC use adversely affects FMD responses compared to healthy age-matched controls (HC).
Methods Forty-two age matched young individuals were recruited into two groups (EC and HC). Brachial artery diameter was continuously imaged using Duplex Doppler ultrasound with a multi-frequency linear-array transducer at baseline and 3 minutes following 5 minutes of forearm ischemia. Video recordings were screen captured and analysed using a researcher independent automated wall tracking software.
Results Baseline brachial artery diameters were not different between EC and HC groups (p>0.05). Post ischemia absolute increase in artery diameter following cuff deflation was significantly lower in EC (0.24 (0.15 – 0.31) median (inter-quartile range)) compared to HC (0.31 (0.22 – 0.37) mm; p<0.02).
Conclusion Endothelium dependent FMD is attenuated in EC users compared to age-matched HC, suggesting an increased risk of future adverse cardiovascular events in EC users.
Conflict of Interest Non
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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