1,720,960 research outputs found
Social structure and demography of a remnant Asian elephant (Elephas maximus) population and the implications for survival
No full textThe Asian elephant Elephas maximus is at risk of extinction as a result of anthropogenic pressures, and remaining populations are often small and fragmented remnants, occupying a fraction of the species' former range. Once widely distributed across China, only a maximum of 245 elephants are estimated to survive across seven small populations. We assessed the Asian elephant population in Nangunhe National Nature Reserve in Lincang Prefecture, China, using camera traps during May-July 2017, to estimate the population size and structure of this genetically important population. Although detection probability was low (0.31), we estimated a total population size of c. 20 individuals, and an effective density of 0.39 elephants per km
2. Social structure indicated a strong sex ratio bias towards females, with only one adult male detected within the population. Most of the elephants associated as one herd but three adult females remained separate from the herd throughout the trapping period. These results highlight the fragility of remnant elephant populations such as Nangunhe and we suggest options such as a managed metapopulation approach for their continued survival in China and more widely.
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Improving generation length estimates for the IUCN Red List
No full textThe International Union for the Conservation of Nature (IUCN) Red List classifies species according to their risk of extinction, informing local to global conservation decisions. Here we look to advance the estimation of generation length, which is used as a time-scalar in the Red List as a way of accounting for differences in species' life-histories. We calculated or predicted generation length for 86 species of antelope following the Rspan approach. We also tested the importance of both allometry (body-mass) and phylogeny (phylogenetic eigenvectors) as predictors of generation length within a Phylogenetic Eigenvector Map (PEM) framework. We then evaluated the predictive power of this PEM and two binning approaches, following a leave-one-out cross-validation routine. We showed that captive and wild longevity data are nonequivalent and that both body-mass and phylogeny are important predictors for generation length (body-mass explained 64% and phylogeny 36% of the partitioned explained variance). Plus, both the PEM, and the binning approach that included both taxonomic rank and body-mass, had good predictive power and therefore are suitable for extrapolating generation length to missing-data species. Therefore, based on our findings, we advise separating captive and wild data when estimating generation length, and considering the implications of wild and captive data more widely in life-history analyses. We also recommend that body-mass and phylogeny should be used in combination, preferably under a PEM framework (as it was less reliant on available reference species and more explicitly accounts for phylogenetic relatedness) or a binning approach if a PEM is not feasible, to extrapolate generation length to missing-data species. Overall, we provide a transparent, consistent and transferable workflow for improving the use of the Rspan method to calculate generation length for the IUCN Red List.</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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