1,720,972 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
Direct and indirect effects of climate change squeeze the local distribution of a habitat-forming seaweed
No full textPredictions concerning biological responses to climate change are based primarily on environmental tolerances of individual species. However, biological interactions and the way these may be altered by changes in climate can also be important drivers of ecological change. A combination of observational and experimental studies was conducted to test the factors controlling the vertical distribution of the canopy-forming alga Fucus guiryi, a cold-water seaweed and ecological engineer. We found that F. guiryi transplanted to areas just above its upper limit of distribution died rapidly, whereas survivorship was high in unmanipulated controls and individuals translocated to areas within the species’ vertical range. Towards the lower limit of its vertical range, unprotected F. guiryi were heavily grazed by a warm-water fish, Sarpa salpa, and percent cover, frond length, and number of reproductive structures were all reduced compared to experimentally protected individuals. Observations over a period of 2 yr suggest that grazing is stronger towards the lower limit of distribution, especially during the warmer seasons of the year. Commercial landing records indicate that the abundance of S. salpa was positively related to warmer sea surface temperatures. Our results highlight the interplay between abiotic and biotic factors in determining the vertical distribution of F. guiryi and suggest that predicted increases in temperature during this century may lead to local extinctions of this ecosystem engineer through the combination of increased physiological stress at its upper limit of distribution and grazing at its lower limit, which, together, act to squeeze its vertical distribution in the rocky intertidal
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
Exploitation of rocky intertidal grazers: population status and potential impacts on community structure and functioning
Full text linkA wide range of anthropogenic activities are impacting the ecology of coastal areas. Exploitation of marine resources is one such activity, which, through cascading trophic effects, can have influences well beyond that of the target species. We investigated the mid-rocky-shore community structure of the Azores archipelago, a seldom-studied habitat, where there is a local tradition of exploiting limpets, the main intertidal grazers. The limpet population structure differed among islands, and there was an inverse relationship between the abundance of larger limpets and the human population per coastal perimeter, but not the associated catch data. At small scales of resolution (quadrats), there was a negative relationship between the cover of algae and limpets and a positive relationship between barnacles and limpets. These relationships were also apparent at the larger scale of islands as a function of the gradient of exploitation. Our results show how natural habitat fragmentation may be useful where the experimental testing of a hypothesis is not possible, and provide evidence for the trophic cascading effects of limpet exploitation at landscape scales
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
Rocky intertidal community structure in oceanic islands: scales of spatial variability
Full text linkThere is a clear bias in the literature on island ecology towards terrestrial rather thanmarine systems, which have remained comparatively poorly studied. Marine populations are typicallyopen, and local production may have little impact on local recruitment, such that long-distancedispersal is an important determinant of population ecology. Since oceanic islands form discretepatches of habitat surrounded by a structurally different environment, we tested the general hypothesisthat processes operating at the scale of islands have a greater influence on these populationsthan the processes operating at smaller, intra-island scales. A hierarchical design examined the patternsof abundance and distribution of conspicuous taxa at 3 tidal heights at a range of spatial scales,ranging from a few meters to hundreds of kilometres apart in the rocky intertidal of the Azores. Bothuni- and multivariate analyses showed that at the largest scale (islands), significant variation wasdetected in the lower and mid-shore communities, but not on the upper shore. Along the verticalgradient of immersion there was a trend for increasing small-scale patchiness towards the top of theshore. The potential role of local environmental stress gradients and broad-scale oceanographicpatterns of recruitment in structuring these assemblages is discussed. This study corroborates thesuitability of the analytical tools used here to examine patterns of distribution over a range of spatialscales and its applicability in the field of island marine ecology
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
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