1,720,993 research outputs found
Failure of Rhodiola rosea to alter skeletal muscle phosphate kinetics in trained men
No full textRhodiola rosea is an herbal supplement purported to improve resistance to stressors and to enhance physical performance, potentially by improving adenosine triphosphate (ATP) turnover. Phosphocreatine (PCr) kinetics serves as a reflection of ATP turnover. The purpose of this investigation was to examine the effect of R rosea ingestion on human skeletal muscle PCr recovery after exhaustive exercise. Twelve resistance-trained men, aged 19 to 39 years, completed incremental forearm wrist flexion exercise to volitional fatigue, once after ingesting 1500 mg R rosea per day for 4 days, and once after ingesting an equivalent placebo dose. During exercise and recovery from exercise, muscle phosphates were examined using phosphorus 31 nuclear magnetic resonance spectroscopy. [PCr] during recovery was fit with a monoexponential function, and the resulting rate constants (k) were compared between groups. Rating of perceived exertion per stage and time to exhaustion were also compared between groups. For R rosea, k = 0.3744 ± 0.1532, whereas for placebo, k = 0.3956 ± 0.2238. Although rating of perceived exertion significantly increased within groups as workload increased, it did not differ between conditions, nor did time to exhaustion (R rosea, 10.71 ± 0.54 minutes; placebo, 10.48 ± 0.68 minutes). Estimates of [PCr] at time 0, 5, 10, 15, and 20 minutes of recovery were nearly identical between groups. In summary, there were no significant differences between groups for any of theparameters measured. Based on these results, we conclude that R rosea ingestion does not improve ATP turnover during or immediately after exercise
Optimum linear and non-linear transformations in feature extraction
Full text linkIn pattern recognition one tries to classify a pattern based on a certain number of observed variables. The observed variables are more often than not redundant. The method of reducing the number of observed variables, or features, is called "Feature Extraction." The solution of the above problem requires the aid of a distance measure. Here a distance measure is obtained geometrically and is compared with the Bhattacharya distance and the Divergence for the n-dimensional Gaussian random variable. Then a method is given to optimally select the features of gaussian random process. A special case of this result gives the optimum linear transformation to reduce the dimension of an n-dimensional Gaussian random vector. The distance measure derived geometrically was used to obtain an optimum non-linear transformation to reduce the number of observed variables. An example was solved on the computer to give a certain amount of comparison among the different methods
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
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
- …
