1,720,961 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
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
Extended phylogeny and morphology of marine and freshwater choanoflagellates with additional methodological studies on heterotrophic flagellates
No full textHeterotrophic flagellates (HF) are small, ubiquitously distributed protists. As main bacterial feeders, they play a significant role in aquatic and terrestrial food webs. To ensure reliable investigations of the diversity and phylogeny of HF and especially choanoflagellates, a short, user-friendly guide to common heterotrophic freshwater flagellates was developed in the present dissertation. It aims at facilitating an easier morphospecies identification using morphological characteristics of the living organisms. Due to the large diversity and specific properties of HF, a reliable quantification of these organisms is very challenging. Different quantification methods such as the live-counting technique, various fixation methods, a cultivation method and molecular tools were thus compared and optimized regarding various environmental studies. On the basis of this comparison different recommendations have been provided.
Among the variety of different groups of HF, special attention was paid to the group of choanoflagellates in the present doctoral thesis. This group is particularly interesting regarding evolutionary aspects on the basis of animal origin as they are known to be the closest protistan relatives to the Metazoa within the group of Opisthokonta. Nonetheless, the internal systematics of choanoflagellates - especially of the order Craspedida - is still controversially discussed as no clear monophyletic clustering could be discovered up to now. Different morphological and life cycle forms exist, inter alia, the presence or absence of a theca (organic cell covering) and the ability to form colonies.
Here, the sequencing of the 18S and 28S ribosomal DNA and morphological description of twelve choanoflagellate isolates (marine, brackish, and freshwater) from world-wide sampling points could reveal new insights into the taxonomy and systematics of the order Craspedida.
Five of the isolates were additionally included in a six-gene phylogenetic analysis (18S rDNA, 28S rDNA, hsp90, tubA, EF-1A and EFL) to obtain an enhanced phylogenetic resolution and evolutionary understanding of choanoflagellates. Besides, it was also possible to characterize a completely new group of undescribed choanoflagellate sequences from suboxic/anoxic environments, closely related to the choanoflagellate order Acanthoecida. This group could be described by one isolate which was assigned to a new genus with a surprising morphological similarity to the order Craspedida. Taken together, this combination of both morphological and molecular data extended the existing choanoflagellate sequence database by about one third and might provide the potential basis for a complete taxonomic revision of choanoflagellates and for insights into their evolution and the evolution of multicellularity. Furthermore, the difficult isolation, cultivation and sequencing processes of choanoflagellates could be partially optimized. Additional ecological studies were carried out regarding salinity tolerances, lorica inducement (covering of acanthoecid choanoflagellates) and feeding modes
A Short Guide to Common Heterotrophic Flagellates of Freshwater Habitats Based on the Morphology of Living Organisms
No full textAuthor-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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