1,720,977 research outputs found
Molecular phylogeny of genus <i>Horaglanis</i> (Indian blind catfishes) within Family Clariidae
No full text Background: India is one of the mega biodiverse countries with a large number of endemic freshwater fishes. Recently, species of genus Horaglanis (family: Clariidae) have been reported from the southern part of India. Due to their unique morphological adaptations, these enigmatic species have been subjected to phylogenetic studies to understand the evolution of adaptive traits. Further, the taxonomic status of these species has not been verified using molecular data.
Methods: In the present study, secondary data i.e. reported sequences of mitochondrial cytochrome c oxidase subunit I gene was used to estimate the genetic divergence values for 14 species of the family Clariidae. Phylogenetic trees were reconstructed using maximum parsimony, maximum likelihood and Bayesian Inference methods.
Results: The average genetic divergence value among genera Clarias-Clariallabes-Platyallabes-Dolichallabes-Gymnallabes-Tanganikallabes-Channallabes was 0.082 ± 0.01. However, these genera showed an average divergence value of 0.296±0.02 with genus Horaglanis. In all tree topologies, species of the genus Horaglanis formed a basal group to all other clariids.
Discussion : The higher genetic divergence value between genus Horaglanis and other genera of Clariidae family suggested that genus Horaglanis may belong to a separate sub family. Based on phylogenetic trees, it is evident that species of Horaglanis might have originated early in the evolution of Clariids than other species.</jats:p
Genetic characterization of Kiddi shrimp, Parapenaeopsis stylifera (H. Milne Edwards, 1837) along the Indian coast using microsatellite markers
No full textNot AvailableParapenaeopsis stylifera (H. Milne Edwards, 1837), popularly known as Kiddi shrimp, constitutes an important fishery resources along the Indian coast with wide geographical distribution. Despite its economic importance, the genetic stock structure of the species is not investigated so far. Knowledge on genetic structure is essential for formulating sustainable management and conservation measures. Present study is carried out to characterize the five geographically isolated stocks of P. stylifera along the Indian coast using microsatellite markers. Eleven polymorphic microsatellites were developed in P. stylifera and used for genetic stock characterization. Including all the stocks, a total of 174 alleles were observed with a mean of 15.81 alleles per locus. Mean observed (Ho) and expected (He) heterozygosity values ranged from 0.641 to 0.692 and 0.710?0.743, respectively. Six loci shown deviation from Hardy-Weinberg equilibrium and no significant linkage disequilibrium between loci pairs were detected. Pair-wise FST, AMOVA and Structure analyses indicated low genetic structure between the stocks of east (Bay of Bengal) and west (Arabian Sea) coasts of India. Based on the present study, P. stylifera stocks of east and west coast of India can be proposed as single management units (MUs), which require single monitoring and management practices
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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