1,720,969 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
Impacts of cumulative thermal and fishery stressors and infection development on the health and survival of adult Pacific salmon during freshwater residence
Cumulative stressors influence the infection development, health and survival of wild Pacific salmon (Oncorhynchus spp.). Infectious disease is generally assumed to be the ultimate cause of death of wild adult salmon, but empirical evidence demonstrating links between infections and early mortality (i.e., prior to spawning) is lacking, especially as a function of cumulative migratory stressors. The influences of high river temperature and fishery capture and release on infection development and early mortality was explored in three Pacific salmon species. Adults were captured at river entry and held in freshwater tanks for the duration of river migration (days–weeks). Tank temperatures reflected either optimal (cool), warm (climate change scenario), or dynamic (changes in river temperature, behavioral thermoregulation) thermal conditions during migration. A subset of fish in all temperature groups was treated with a fishery bycatch release simulation (gillnet entanglement, air exposure) at the start of the holding period. We tracked shifts in physiology, immune activity and multiple infections using repeated biopsy (gill, blood) and molecular tools. Laboratory experiments were complimented by a telemetry study to assess impacts on behavior in the river. Novel application of high-throughput qPCR on nonlethally-sampled gill measured infections (bacteria, viruses, protozoa) concurrently with host immune gene expression, and was complemented by blood plasma chemistry to assess physiology. Ecologically relevant high temperatures increased mortality, infection development and stress metabolites and impaired host osmoregulatory function. Fishery stress reduced survival, especially after long entanglements and at high temperature, which reduced the capacity of individuals to resolve stress and infections. Females were more drastically affected, and mortality was delayed by more than a week. Fish with heavy infections in the river migrated more rapidly but traveled less distance. Sublethal effects of stressors included reduced migration rates and suppressed maturation indices that could delay maturity and extend river residence. Finally, river-exposed fish carried heavier infections and died sooner than those that bypassed the lower river, suggesting a causal influence of infections on early mortality. These findings support river-derived infections as causal factors contributing to the early mortality of adult Pacific salmon in fresh water and clarify its mechanisms, which comprise influences of multiple infections, sex, species, water temperature and fishery stress.Graduate2019-04-1
Variations on the Author
“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
We 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
Host-pathogen-environment interactions determine survival outcomes of adult sockeye salmon (Oncorhynchus nerka) released from fisheries
Stressful environments enhance the pathogenicity of infectious agents. But can pathogens decrease host stressor resilience? We tested the hypothesis that enhanced infections reduce the resilience of wild adult sockeye salmon (Oncorhynchus nerka) to single and cumulative stressors. To manipulate initial infections, some returning adults were collected in the marine environment prior to entering the Fraser River, British Columbia, and another group was collected after freshwater entry. Fish were held in freshwater tanks for up to 4 weeks at historical (14°C) or projected future migration temperatures (18°C). The cumulative impact of fisheries non-retention was evaluated by exposing fish to a mild (seine) or severe (gill net) fishery treatment at collection. Using weekly nonlethal gill biopsies and high-throughput qPCR, we measured up to 46 infectious agents with host stress and immune gene expression. Marine-captured fish had less severe infections than river-captured fish: a short migration (100 km, 5-7 d) that produced profound infection differences. At 14°C, river-captured fish survived 1-2 weeks less than marine captured fish. All fish held at 18°C died within 4 weeks unless they were not handled, and few river-captured fish survived. Gene expression correlated with infections in river-captured fish, while marine-captured fish were more stressor-responsive. Our results implicate river-derived infections as causal factors of stressor-mediated early mortality in migrating adult sockeye salmon, whereas cumulative stressors were detrimental regardless of initial infections due to extreme physiological disturbance. We propose that river entry decreases stressor resilience of adult Pacific salmon by shifting infections and redirecting host responses toward disease resistance
Dispelling the Myths Behind First-author Citation Counts
We 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
We 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.
Author-wise bibliometric analysis based on entropy.</p
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