1,721,112 research outputs found
Effectiveness of lead dust control and genetic susceptibility to lead absorption.
No full textVariation in blood lead among children is due to interplay of environmental, nutritional, and genetic factors. A major source of childhood lead exposure is floor dust. Children on diets low in calcium have increased susceptibility to lead toxicity. Calcium metabolism is controlled, in part, by the vitamin D3 receptor (VDR) gene. To determine the effect of interior dust control on children's blood lead concentrations, a systematic review of randomized, controlled trials of dust control interventions was conducted. No significant differences were found in mean change in blood lead concentration for children by random group assignment. There was a significant difference in the percentage of children with blood lead ≥15 mug/dL between the intervention and control groups, 6% vs. 14% (OR = 0.40, 95% CI = 0.21 to 0.80) and in the percentage of children with blood lead ≥20 mug/dL between the intervention and control groups, 2% vs. 6% (OR = 0.29, 95% CI = 0.10 to 0.85). Using a repeated measures statistical model, the relationship between blood lead concentration and the VDR-Fok1 polymorphism was evaluated in a longitudinal cohort of 275 children. Children with VDR- FF genotype had higher blood lead concentrations than children with VDR-Ff and -ff (p = 0.04). A significant interaction was found between floor dust lead loading and VDR-Fok1 genotypes on blood lead concentration. For every 1 mug/ft 2 increase in floor dust, children with genotype FF had a 1.1% increase in blood lead (95% CI, 1.5 to 0.69), whereas children with the Ff genotype had a 0.53% increase in blood lead (95% CI, 0.1 to 0.92). In conclusion, although dust control was associated with 50% or greater reduction in the proportion of children who had blood lead concentrations exceeding 15 mug/ft2 and ≥20 mug/ft2 there was no substantial effect on mean blood lead concentration. And, the VDR-Fok1 polymorphism significantly modifies lead exposure in children and at least partially explains the variation in children's blood lead concentrations.Doctor of Public Health (DPH)Biological SciencesGeneticsHealth and Environmental SciencesPublic healthToxicologyUniversity of Michigan, Horace H. Rackham School of Graduate Studies, School of Public Healthhttp://deepblue.lib.umich.edu/bitstream/2027.42/129022/2/3041416.pd
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Association of Secondhand Smoke Exposure with Pediatric Invasive Bacterial Disease and Bacterial Carriage: A Systematic Review and Meta-Analysis
No full textBackground: A number of epidemiologic studies have observed an association between secondhand smoke (SHS) exposure and pediatric invasive bacterial disease (IBD) but the evidence has not been systematically reviewed. We carried out a systematic review and meta-analysis of SHS exposure and two outcomes, IBD and pharyngeal carriage of bacteria, for Neisseria meningitidis (N. meningitidis), Haemophilus influenzae type B ( Hib), and Streptococcus pneumoniae (S. pneumoniae).Methods and Findings: Two independent reviewers searched Medline, EMBASE, and selected other databases, and screened articles for inclusion and exclusion criteria. We identified 30 case-control studies on SHS and IBD, and 12 cross-sectional studies on SHS and bacterial carriage. Weighted summary odd ratios (ORs) were calculated for each outcome and for studies with specific design and quality characteristics. Tests for heterogeneity and publication bias were performed. Compared with those unexposed to SHS, summary OR for SHS exposure was 2.02 (95% confidence interval [CI] 1.52-2.69) for invasive meningococcal disease, 1.21 (95% CI 0.69-2.14) for invasive pneumococcal disease, and 1.22 (95% CI 0.93-1.62) for invasive Hib disease. For pharyngeal carriage, summary OR was 1.68 (95% CI, 1.19-2.36) for N. meningitidis, 1.66 (95% CI 1.33-2.07) for S. pneumoniae, and 0.96 (95% CI 0.48-1.95) for Hib. The association between SHS exposure and invasive meningococcal and Hib diseases was consistent regardless of outcome definitions, age groups, study designs, and publication year . The effect estimates were larger in studies among children younger than 6 years of age for all three IBDs, and in studies with the more rigorous laboratory- confirmed diagnosis for invasive meningococcal disease (summary OR 3. 24; 95% CI 1.72-6.13).Conclusions: When considered together with evidence from direct smoking and biological mechanisms, our systematic review and meta- analysis indicates that SHS exposure may be associated with invasive meningococcal disease. The epidemiologic evidence is currently insufficient to show an association between SHS and invasive Hib disease or pneumococcal disease. Because the burden of IBD is highest in developing countries where SHS is increasing, there is a need for high- quality studies to confirm these results, and for interventions to reduce exposure of children to SHS
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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