1,721,066 research outputs found
Evaluation of concordance between labelling and content of 52 hair dye products: overview of the market of oxidative hair dye
No full textBackground: Hair dyes contain strong allergens and are widely available. Correct labelling is a necessity in order to provide information about the contents. Objectives: To compare the labelling and content of hair dyes. Materials and methods: In total, 52 hair dyes, from 11 different countries, were bought over the counter. High-pressure liquid chromatography was used for the analysis of p-phenylenediamine (PPD), toluene-2,5-diamine (2,5-TDA), and three oxidation products of PPD. Results: There was good agreement between labelling and content, although seven of the 52 products (13.5%) studied were incorrectly labelled. There were differences in the geographical use of PPD and 2,5-TDA; 2,5-TDAwas more common in European products, while PPDwas more common in products purchased outside Europe andwas present in higher concentrations. Conclusion: All dyes purchased in Europe contained PPD and 2,5-TDA at levels within the limits defined by European legislation, however, levels were higher in some products purchased outside Europe. Only a small group of hair dyes sold in Europe were mislabelled. Further improvement in labelling, by providing the concentration of chemicals, may facilitate products to be purchased both locally and within the global market, when travelling or on the internet
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
Chemical and Clinical Studies of Isocyanate Contact Allergy with focus on diphenylmethane diisocyanate
No full textIsocyanates are highly reactive compounds used in the production of polyurethane. Exposure to isocyanates is mainly associated with respiratory disorders, but may also result in allergic contact dermatitis. Reports describing contact allergy to isocyanates are few in number and it has been considered a rare phenomenon. In the present study it is shown that the low frequency of reported cases could partly be explained by weaknesses in the method used to detect contact allergy arising from isocyanates, i.e. patch testing with the commercially available isocyanate series. These series generally comprise petrolatum preparations of the four diisocyanates diphenylmethane-4,4'-diisocyanate (4,4'-MDI), 2,4-toluene diisocyanate (2,4-TDI), 1,6-hexamethylene diisocyanate (1,6-HDI) and isophorone diisocyanate (IPDI), as well as two corresponding amines, 4,4'-diaminodiphenylmethane (4,4'-MDA) and isophorone diamine (IPDA). The following results are reported in the thesis. (i) Chemical analyses of isocyanate series obtained from four American and nine European patch testing departments showed that patch test preparations of 2,4-TDI, 1,6-HDI and IPDI contained the declared concentrations, but the concentration of 4,4'-MDI was generally so low that patch testing with it could not be considered reliable. (ii) A stability study showed that preparations of technical grade MDI, i.e. polymeric MDI (PMDI), were more stable and more homogeneous than preparations of pure 4,4'-MDI during the course of a year. (iii) A patch test study revealed that PMDIs rendered as many positive reactions as 4,4'-MDI, (iv) that positive reactions to 4,4'-MDI and PMDI appear late, i.e. after day 3 and sometimes also after day 7, and (v) that the amine 4,4'-MDA is a good marker for 4,4'-MDI contact allergy. In order to optimize patch testing with isocyanates it is thus recommended that patients be tested with their own work products containing technical grade isocyanates since they better reflect the possible allergens that patients are in fact exposed to. It is not yet known if the isomers presently used in commercial preparations are the most potent allergens in technical grade products or if there are other monomers and/or oligomers that cause skin problems. When contact allergy to MDI is suspected patients can also be tested with 4,4'-MDA since it is a marker for 4,4'-MDI contact allergy. Isocyanate patch tests should be read on day 3 or 4 as well as on day 7
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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