1,721,026 research outputs found
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
A new and sensitive approach for immunohistochemical analysis on formalin fixed murine tissues
No full textBackground. Immunohistochemistry (IHC) is the localization of antigens in different tissues using specific primary and secondary antibodies. IHC is widely used in basic research and surgical pathology, both in human and animal models. Frozen and fixed tissues can be used but fixation and paraffin embedding offer the best option for preserving the specimen morphology. Unfortunately, the most common fixative (10% buffered formalin) may alter the biochemistry of the proteins and mask antigens. For this reason, antigen retrieval is required to allow antigen-antibody binding and different types of digestive enzymes or heat-induced methods can be used.
Murine models have always been a challenge for IHC due to low sensitivity of mouse antibodies binding mouse tissues and limited availability of immunohistochemical reagents for formalin fixed tissues. In fact, most of the mouse-specific antibodies are only functional on frozen tissues but the quality of frozen sections is not good enough for morphological evaluation.
Aim. To propose a new and sensitive approach, based on heat-antigen retrieval, for IHC on formalin fixed-paraffin embedded murine tissues in order to provide a useful panel of antibodies for immunology research.
Methods. Tissues: murine colon, small bowel, lung, spleen. Fixative: 10% buffered formalin (24 hour at room temperature). We used a pressure cooker specifically designed for antigen retrieval (temperature of 125 C degrees and 20 psi, unmasking buffer at pH 6.00 which turns during boiling to 7.00) and tested a panel of 31 antibodies to identify leukocytes, endothelial and epithelial cells, cytoskeleton molecules, proliferation markers, and cytokines. These antibodies either cross-reacted with murine antigens or were mouse-specific. Immunohistochemical staining was carried out on an automated immunostainer. We compared several dilutions of the antibodies, and used various detection systems.
Results. See table 1. Overall, 21 of the tested antibodies showed specific positivity (highlighted in white), 4 antibodies failed to work (highlighted in red) and 6 produced a strong background which made it difficult to analyze the results (highlighted in yellow). The morphology of the cells and tissues was entirely preserved in all of the samples. In table 1 we reported the technical characteristics of the antibodies and our results in terms of: recommended concentration, recommended detection system for each antibody.
Conclusions. We demonstrated the useful application of an innovative method for immunohistochemical analysis on formalin fixed murine tissues: the decloaking chamber. This method will guarantee to deliver a clear and specific staining compared to other well recognized technique
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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