1,720,961 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
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
Nuclear protein kinase C-delta: possible check-point of cell cycle progression
No full textProtein kinase Cs (PKCs) belong to a serine/threonine kinase family, ubiquitously expressed and claimed to be involved in physiological processes including apoptosis, cell growth and differentiation. The question of the subcellular localization and activity of PKCs remains to be clarified. Here we report that nuclear PKC-delta cooperates to regulate the S-G2/M phase transition of cell cycle, apparently being associated to chromosome condensation and alignment on the metaphase plate
Erythroid cell differentiation is characterized by nuclear matrix localization and phosphorylation of protein kinases C (PKC) alpha, delta, and zeta.
No full textProtein kinases C (PKC) xi expression and phosphoryation at nuclear level during dimethyl sulfoxide (DMSO)-induced differentiation in Friend erythroleukemia cells have been previously reported, suggesting a possible role of this PKC isoform in the DMSO-related signaling. In order to shed more light on this tantalizing topic, we investigated PKC intracellular and sub-cellular localization and activity during DMSO-induced erythroid differentiation. Results indicated that at least PKC a, C, and 8 are strongly and temporally involved in the DMSO-induced differentiation signals since their expression and phosphorylation, though at different extents were observed during treatments. Intriguingly, while PKC a and associate to the nuclear matrix during the differentiation event; PKC 8 appears to be residentially associated to the nuclear matrix. Furthermore an evident downregulation of the beta-globin gene transcription (differentiation hallmark) was detected upon a progressive inhibition of these PKC isoforms by means of specific inhibitors, indicating, therefore, that PKC a,, and 8 phosphorylation play a crucial role in the control of erythroid differentiation
Parallel regulation of PKC-alpha and PKC-delta characterizes the occurrence of erythroid differentiation from human primary hematopoietic progenitors.
No full textObjective: Erythroid differentiation is a process characterized by modulation of different proteins including phosphoinositide-related enzymes such as protein kinase C (PKC) isoforms. Because in different cell lines PKC-α and PKC-δ have been reported to be involved in the mechanisms controlling proliferation and differentiation, the aim of this study was to examine the relative involvement of these PKC isoforms in the development of CD235a+ erythroid cells from human healthy hematopoietic progenitors. Materials and methods: Erythroid differentiation from human primary hematopoietic progenitor cells was achieved by adopting the human erythroblasts mass amplification culture. Expression and activity of PKC isoforms and their relationship with proliferation and differentiation were investigated by morphologic analysis, reverse-transcriptase polymerase chain reaction, Western blotting, multiparametric flow cytometry, and transfection experiments. Results: PKC-α was found expressed and phosphorylated in cells undergoing both proliferation and differentiation, although PKC-δ, largely expressed and activated during proliferation, was evidently downregulated during differentiation. Overexpression of PKC-δ-CAT scarcely influenced the development of glycophorin-A (CD235a)+ erythroid cells from hematopoietic progenitors, although overexpression of PKC-α-CAT strongly induced the development of CD235a+ erythroid cells. On the other hand, in PKC-α-CAT-transfected cells, pharmacologic inhibition of PKC-δ further increased the number of CD235a+ cells, although inhibition of PKC-α resulted in an evident impairment of the development of CD235a+ erythroid cells. Conclusions: Our results indicate that the suppression or at least a strong downregulation of PKC-δ, concomitant to PKC-α expression and activity, might be a cofactor to be further investigated and might be involved in the events regulating erythropoietin-induced erythroid differentiation from human primary hematopoietic progenitor cells
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