1,720,964 research outputs found
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
Molecular epidemiology, clonality and virulence of Dichelobacter nodosus, the agent of ovine footrot
Get PDFDichelobacter nodosus, an anaerobic bacterium, is the major transmissible agent of ovine footrot. The disease expresses as a virulent or benign lesion in the hoof. Virulence is related to the production of serine proteases, particularly a thermostable protease. Isolates of D. nodosus are characterised according to the type of protease produced (either heat-stable or heat-labile) and the electrophoretogram (zymogram) of the protease. This study reports on the use of the DNA-based typing techniques Pulsed-Field Gel Electrophoresis (PFGE) and Infrequent-Restriction-Site-PCR (IRS-PCR) to investigate the molecular epidemiology of D. nodosus, including a consideration of the relationship between genetic type, zymogram patterns and whole cell protein profiles.
The aim of the project was to obtain a better understanding of D. nodosus strain diversity and dissemination in Australia and its relationship to virulence within the population. The overall intention was to use this information to assist in the long-term control of virulent footrot.
Field isolates of D. nodosus from Western Australia (n = 735), New South Wales (n = 16), Victoria (n = 24) and South Australia (n = 21) were obtained and analysed. Both typing techniques that were used offered good differentiation between isolates for epidemiological purposes, and the results were in general agreement. PFGE provided slightly better discrimination between isolates, with 214 PFGE types (181 from Western Australia) compared to 94 IrsT types (77 from Western Australia). Within this diverse range of molecular types clonality was observed - with clones being defined as clusters of isolates having closely related PFGE types. The strains were categorised as genetically diverse, genetically similar or identified as the same strain. This diversity of genetic types was found overall, within flocks of sheep on a farm and within a single hoof where, on a number of occasions, multiple molecular types and zymogram types were found colonising a single hoof. One isolate that was experimentally inoculated into a flock of sheep produced six different genetic types when tested 12 months after the initial infection. This indicates that D. nodosus undergoes rapid genetic change, which means that follow-up epidemiological investigation of disease outbreaks and trace-backs need to be done as soon after infection as possible. The genetic differences appeared to be due to large insertions or deletions of DNA.
Amongst sheep on some properties, isolates that had a different protease expression and virulence expression were found to have the same molecular type. Investigation of these isolates by SDS-PAGE showed that they also had the same whole cell protein profiles. Isolates from the same clonal groups also had the same protein profile, whereas genetically diverse isolates had different protein profiles. The lack of protein differences between isolates of the same molecular type, or within a clonal group, suggests that the differences in protease thermostability may be due to conformational changes in the protein, rather than to overall detectable genetic change and/or expression of different proteins. These results demonstrate that PFGE typing can be useful in predicting likely phenotypic expression of whole cell proteins. Further work is required to elucidate differences between virulent and benign strains of D. nodosus
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
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