1,720,977 research outputs found
Chlorination disinfection by-products and adverse birth outcomes: a retrospective cohort study in three regions in England: ISEE-183
No full textRecent epidemiological studies of the relationship between disinfection by-products (DBPs), from chlorination, in public drinking water supply and adverse birth outcomes, have reported inconsistent and inconclusive findings. We report here on the largest study to date to examine the relationship of total trihalomethanes (TTHMs) and the individual trihalomethanes (THMs) to birth weight and still birth prevalence, between 1993 and 1998, for regions covered by three water companies in England. Initial results from this ongoing study using modelled annual TTHM estimates were found to differ between each of the three water supply areas. There was some evidence of confounding by social deprivation and ethnicity, which was further explored by analysis of information on the lifestyle characteristics of all women of reproductive age in the study regions from National survey data. Here, we report on the next stage of the study using modelled quarterly (3 monthly) estimates of the individual THMs in water zones. We modelled THM measurements using a Bayesian hierarchical mixture model, taking into account heterogeneity in THM levels between water originating from different source types (e.g. ground, lowland surface or upland surface), quarterly variation in THM levels and uncertainty in the true value of undetected and rounded measurements. These modelled estimates were linked using Geographical Information Systems to routine birth and stillbirth records based on location of maternal residence at the time of birth to obtain a weighted third trimester exposure estimate for each birth. Exposure categories were constructed as follows: for chloroform (low (< 20 mg/l). medium (20-40 mg/l) and high (>40 mg/l), bromodichloromethane (low (< 6 mg/l), medium (6-12 mg/l) and high (>12 mg/l), dibromoehloromethane (low (< 5 mg/l) and high (>5 mg/l) and total brominated compounds low (< 6 mg/l), medium (6-12 mg/l) and high (>12 mg/l) respectively. After exclusion of multiple births and births from water zones without valid THM data, we studied a total of 934,843 live and stillbirths. Exposure-response relationships were explored using multiple logistic regression analysis with weighted third trimester individual THM estimates and adjustment for e.g. gender, maternal age and deprivation. Analysis of the individual THMs, as opposed to TTHMs. is essential to characterise more precisely the effects of complex mixtures of DBPs on the developing foctus, and refine our understanding of this important area of research
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
Occurrence of DBPs in drinking water of European regions for epidemiology studies
No full textKrasner, S.W., Kostopoulou, M., Toledano, M.B., Wright, J., Patelarou, E., Kogevinas, M., Villanueva, C.M., Carrasco-Turigas, G., Marina, L.S., Fernández-Somoano, A., Ballester, F., Tardon, A., Grazuleviciene, R., Danileviciute, A., Cordier, S., Costet, N., Righi, E., Aggazzotti, G., Stephanou, E.G., Kargaki, S., Nieuwenhuijsen, M.J
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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