1,720,998 research outputs found
Growth hormone predicts bone density in elderly women
No full textEvidence is accumulating that the risk of osteoporosis may be influenced by environmental factors during intrauterine and early postnatal life; such programming might be mediated through modification of the GH/IGF-1 axis during critical periods in its development. To address this issue, we explored the relationships among birth weight, circulating GH profile, bone density, and bone loss rate in a group of British women. The study population consisted of 38 women 60–75 years old resident in Hertfordshire for whom detailed birth records were available. Twenty-four-hour circulating GH profiles were obtained during an inpatient stay on a metabolic ward, after an overnight rest. The circulating profile of GH was characterised by estimating the peak, median, trough, and total concentrations from 72 samples measured sequentially over 24 h in each subject. Bone mineral density was assessed at the lumbar spine and femoral neck at baseline and at follow-up 4 years later. Lumbar spine bone mineral content (BMC) and density (BMD) were positively associated with all measures of GH concentration, although relationships were strongest for BMC with trough GH (r = 0.47, P < 0.01). Associations persisted after adjustment for age, body mass index, smoking, alcohol consumption, physical activity, and osteoarthritis score in multiple regression models. However, associations of GH concentration with femoral neck BMC were weak, and there was no association between any measure of GH concentration and bone loss at either site. Total (integrated) daily GH concentration tended to increase (P = 0.08) with rising birth weight, while IGF-1 concentration fell (P = 0.05) with rising birth weight, suggesting a role for the GH/IGF-1 axis in the programming of adult bone mass among women
Occupational physical activities and osteoarthritis of the knee
No full textObjective: to assess the risk of knee osteoarthritis (OA) associated with kneeling, squatting, and other occupational activities.Methods: we compared 518 patients who were listed for surgical treatment of knee OA and an equal number of control subjects from the same communities who were matched for sex and age. Histories of knee injury and occupational activities were ascertained at interview, height and weight were measured, and the hands were examined for Heberden's nodes. Data were analyzed by conditional logistic regression.Results: after adjustment for body mass index (BMI), history of knee injury, and the presence of Heberden's nodes, risk was elevated in subjects who reported prolonged kneeling or squatting (odds ratio [OR] 1.9; 95% confidence interval [95% CI] 1.3-2.8), walking >2 miles/day (OR 1.9; 95% CI 1.4-2.8), and regularly lifting weights of at least 25 kg (OR 1.7; 95% CI 1.2-2.6) in the course of their work. The risks associated with kneeling and squatting were higher in subjects who also reported occupational lifting, and appeared to interact multiplicatively with the risk conferred by obesity. People with a BMI of 30 kg/m2 whose work had entailed prolonged kneeling or squatting had an OR of 14.7 (95% CI 7.2-30.2), compared with subjects with a BMI <25 kg/m2 who were not exposed to occupational kneeling or squatting.Conclusion: there is now strong evidence for an occupational hazard of knee OA resulting from prolonged kneeling and squatting. One approach to reducing this risk may lie in the avoidance of obesity in people who perform this sort of work
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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