1,720,993 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
Pathways of larval transport : the roles of alongshore and cross shore transport
Full text linkAbstract: Until recently, populations of broadcast spawning coastal invertebrates have been considered panmictic, but numerous studies have identified genetic structure at surprisingly small geographical scales. The present study investigated the role of coastal currents in shapingthe genetic structure in one of southern Africa’s best studied marine invertebrates, the brown mussel Perna perna, within Africa’s most intensively monitored marine regions, the “Sentinel Site” on the south-east coast of South Africa. Unlike previous studies, most of which used slow-evolving mitochondrial DNA markers and all of which inferred larval connectivity on the basis of genetic structure found in adults, the present study used more informative polymorphic microsatellite data that were generated for both adults and larvae collected at nearshore sites. Concurrent with previous studies carried out on the same coastline, a western and an eastern mussel lineage were identified whose ranges overlap in this region. There was however also evidence that the eastern lineage can be subdivided further into two microsatellite-based clusters. The range of one extends to the east coast, while that of the other seems to be centered on the eastern portion of the south-east coast. Adult sites could be assigned to either the western or the eastern lineage, with no intermediate populations. Larvae were relatively homogeneous throughout the study area, but most, including those in the western portion of the Sentinel Site, could be assigned to the eastern lineage, suggesting that the majority of larvae found in the nearshore western areas contribute little to larval settlement at those sites. The present study suggests that most of the larvae may have originated from the area east of the Sentinel Site. Moreover, those larvae that have been dispersed over such scales by cross shore and offshore transport do not necessarily establish themselves in the new habitats. Thus, adults are not panmictic as previously thought and larvae are “open” across a broad, 150 km range of origin. These patterns reinforce that differential delivery, where some sites receive more settlers than others, really could shape...M.Sc. (Zoology
Genetic connectivity in the world’s largest freshwater copepod
Full text linkAbstract: Temporary water bodies (temporary ponds) are home to a number of crustacean taxa with interesting life cycles. These environments only hold water for a limited period, drying out completely for extended periods of time. Population persistence for many species is reliant on the production of dormant propagules capable of withstanding desiccation. Temporary water bodies are scattered across the landscape and are essentially isolated from each other, but research has shown that dormant propagules may be transported between different ponds via mammal, bird and wind dispersal. However, it is unknown how frequently this occurs, and whether species-level genetic divergence between populations takes place at ecological or evolutionary timescales (i.e. decades vs. millennia). Lovenula raynerae is a recently described copepod that is thought to be the largest freshwater copepod known to science and is found exclusively in temporary ponds in the Eastern Cape of South Africa. The aims of the present study were threefold. First, the genetic connectivity among spatially separated populations (ponds) was reconstructed using partial sequences of the mitochondrial COI gene and the nuclear 18S rRNA. Secondly, I aimed to investigate historical migration events of the species lineages to determine divergence times within the species. Thirdly, the whole mitochondrial genome of the species was reconstructed to gain a better understanding of phylogenetic relationships within the Copepoda, which have received little previous attention despite their ubiquity and importance in the food web. Out of 365 specimens collected in 46 ponds, five major evolutionary lineages were identified that were highly divergent, and levels of genetic structure between the temporary ponds were extremely high (ST = 0.927). It was further found that L. raynerae has a complex history of connectivity that dates back to the Pleistocene and perhaps even the Pliocene. Phylogenetic analyses using the complete mitochondrial genome data show that L. raynerae has a monophyletic relationship with Calanus hyperboreus, and these two calanoid copepods have a sister taxon relationship with...M.Sc. (Zoology
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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