1,721,398 research outputs found
Interactions of antibodies and their derivatives with leukaemia cell surfaces
No full textStudies have been made of the effects of the interaction of antibodies with the surface immunoglobulin of guinea pig L2C B-lymphoblastic leukaemia cells. Firstly, investigations were made into the behaviour of the surface immunoglobulin both in the absence and presence of such antibodies, and secondly extensive studies were undertaken into the effects of accessory cells upon the ability of such antibodies to induce modulation (the redistribution and internalization) of the surface immunoglobulin. In the first section use was made of a system in which the fate of the surface immunoglobulin could be traced without its ligation in situ with antibodies. These studies showed that the surface immunoglobulin was being continuously internalized by the L2C cells, and suggested that some recycling of the surface immunoglobulin may occur. The effects of univalent and bivalent fragments of anti-immunoglobulin antibodies were then studied. Univalent fragments did not induce any modulation of the surface immunoglobulin, but were continuously internalized at a slow rate. They were not degraded within the cell to any detectable extent. In contrast, bivalent fragments induced rapid modulation of the surface immunoglobulin and were extensively degraded within the cell. In the second section it was demonstrated that the in vitro modulation of L2C cell surface immunoglobulin induced by anti-immunoglobulin antibodies was enhanced in the presence of isolated guinea pig Kupffer cells. It was also shown that univalent antibody derivatives containing Fc regions were able to induce modulation in vitro only in the presence of Kupffer cells. Further studies showed that this was due to the physical interaction of the Kupffer cells with the antibody-coated cells, via the Fc portion of the antibody and the Fc receptors on the Kupffer cell surface. Modulation enhancement was mediated by all of the Fcγ receptors studied on guinea pig, rat and human cells. The degree of modulation enhancement was related to the level of Fc receptors on the accessory cell surface. Functional studies indicated that modulation enhancement resulted in significant protection of the tumour cells from complement-mediated lysis. It was shown using antibodies to other cell surface antigens on human cell lines that modulation enhancement occurred with all three antigens studied. In vivo studies into the effects of anti-immunoglobulin treatment of leukaemic guinea pigs demonstrated that tumour cells were rapidly cleared from the circulation by bivalent reagents and also by an Fc containing univalent derivative. However only reagents containing Fc regions induced surface immunoglobulin modulation in vivo to any greater extent than in vitro, demonstrating the importance of in vivo modulation enhancement by Fc receptor bearing cells.</p
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
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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