1,720,959 research outputs found
Coral Reef Degradation In The Indian Ocean: Status Report 2005.
No full textResilience, in the context of the capacity for populations of zooxanthellae to recover after coral bleaching, is a little-studied but crucial aspect of coral responses to bleaching stressors. This study investigated resilience to experimental bleaching induced by elevated temperature and darkness in the scleractinian species Porites cylindrica. Resilience, as assessed by changes in densities of zooxanthellae on termination of the stressor, was influenced by the nature and duration of the stressor. Zooxanthellae in corals subjected to relatively long durations of darkness were more resilient than those in corals treated for shorter durations. The opposite trend was evident for zooxanthellae in corals exposed to elevated temperature. The basis for these contrasting results may lie in different endodermal processes occurring during treatment with the two stressors. Localised coral bleaching occurs in response to a range of stressors, and this study has strong implications for recovery of corals in the field after natural bleaching incidents. The relevance of these experiments on resilience to field bleaching events is discussed.Publishe
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
The Diversity and Bleaching Responses of Zooxanthellae in Kenyan Corals.
No full textZooxanthellae of the genus Symbiodinium. the dinoflagellate endosymbioms. of many benthic cnidarians. are phylogenetically diverse. Molecular analyses of ribosomal RNA genes indicate multiple Symbiodimum species in 7 known phylotypes, A-G. The diversity of Symbiodirlium in corals from Kenya and sea anemones from the Mediterranean Sea was investigated by molecular methods. Symbiudinium in Kenya comprise phy[otype A, C and D zooxanthellae that occur pan-tropically. The majority of Mediterranean Symbiodinium comprise a distinct group of 'temperate A' zooxanthellae that may be regionally endemic. The zooxanthellal chloroplast psbA gene, encoding the D1 protein of photosystem II, was sequenced. The psbA and nuclear 248 rRNA gene trees were congruent. Resilience, i.e. the capacity for zooxanthelJae 10 recover after bleaching, to bleaching induced by elevated temperature and darkness was investigated in Porites cylindrica. Resilience was assessed by changes in zooxanthellal densities on termination of stressor. Resilience was influenced by the nature and duration of stressor. Zooxanthellae in corals subjected to relatively long durations of darkness were more resilient than those in corals treated for shorter durations. The opposite trend was evident for zooxanthellae in corals exposed to elevated temperature. The basis for these contrasting results may lie in different endodennal processes during treattnent with the two stressors. The recovery profile of corals that bleached on the reef was similar to those experimentally hleached using elevated temperature. No detectable changes in the molecular identity of zooxanthellae occurred on recovery. Porites cylindrica recently recovered from experimenlally induced bleaching and bleaching induced by natural stressors were subjected to a repetition of bleaching stressors to explore their capacity for acclimation, i.e. the development of resistance to bleaching stressors under laboratory conditions. Bleaching responses were not significantly affected by prior experience of bleading stressor. The relevance of these experiments on coral resilience and acclimation to field bleaching events is discussed.Ph
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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