1,720,964 research outputs found

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    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

    Variations on the Author

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    “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

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    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

    Dispelling the Myths Behind First-author Citation Counts

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    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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    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

    Structure and Dynamics of a Tropical Dry Forest Plant Community

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    This thesis is spurred by the overarching question “why is a plant where it is in space and time?”, which, when asked in different global communities over the last century or so, has contributed to the development of general theories of plant community ecology and has provided information relevant to understanding, managing, and predicting the future of those communities. The question is asked in the context of a seasonally dry tropical forest (SDTF) plant community in southern India, based on long-term research conducted in a permanent 50-ha sampling plot. We employ a layered approach to answering this question, wherein we deconstruct the structure and dynamics of the plant community by first establishing the spatial structure of soils, topography and lithology in the plot. Next we assess how this spatial structure, together with temporal variation in precipitation, affects plant abundances in space and time. Next we break up abundance variation into the components of recruitment, mortality and stem radial growth and assess how these respond to variation in environmental factors such as precipitation, temperature, soils, topography and fire, and biotic neighborhoods. In Chapter 2, we examine the roles of lithology, topography, vegetation and fire in generating local-scale (<1 km2) soil spatial variability in the 50-ha plot. For this, we mapped soil (available nutrients, Al, total C, pH, moisture and texture in the top 10cm), rock outcrops, topography, all native woody plants ≥1 cm diameter at breast height (DBH), and spatial variation in fire frequency (times burnt during the 17 years preceding soil sampling) in a permanent 50-ha plot. Unlike classic catenas, lower elevation soils had lesser moisture, plant-available Ca, Cu, Mn, Mg, Zn, B, clay and total C. The distribution of plant-available Ca, Cu, Mn and Mg appeared to largely be determined by the whole-rock chemical composition differences between amphibolites and hornblende-biotite gneisses. Amphibolites were associated with summit positions, while gneisses dominated lower elevations, an observation that concurs with other studies in the region which suggest that hillslope-scale topography has been shaped by differential weathering of lithologies. This “inverse catena” pattern is possibly reinforced by topography due to nutrient leaching and clay depletion in the drainage area. Neither NO3--N nor NH4+-N was explained by the basal area of trees belonging to Fabaceae, a family associated with N-fixing species, and no long-term effects of fire on soil parameters were detected. A strong SW-NE trending P pattern remained unexplained by any of the factors considered. Local-scale lithological variation is an important first-order control over soil variability at the hillslope scale in this SDTF, by both direct influence on nutrient stocks and indirect influence via control of local relief. The extent to which interspecific niche differences structure plant communities is highly debated, with extreme viewpoints ranging from fine-scaled niche partitioning, where every species in the community is specialized to a distinct niche, to neutrality, where species have no niche or fitness differences. However, there exists a default position wherein niches of species in a community are determined by their evolutionary and biogeographic histories, irrespective of other species within the community. According to this viewpoint, a broad range of pair-wise niche overlaps – from completely overlapping to completely distinct – are expected in any community without the need to invoke interspecific interactions. In Chapter 3, we develop a method that can test for both habitat associations and niche differences along an arbitrary number of spatial and temporal niche dimensions and apply it to a 24-year data set of the eight dominant woody-plant species (representing 84% and 76% of total community abundance and basal area, respectively) from the 50-ha plot, using edaphic, topographic and precipitation variables as niche axes. Species separated into two broad groups in niche space – one consisting of three canopy species and the other of a canopy species and four understory species – along axes that corresponded mainly to variation in soil P, Al and a topographic index of wetness (the second and fourth principal components (PCs) of soil and topographic variables). All three species from the former group and one understorey species from the latter group showed evidence of niche specialization along the same axes. Based on the landscape-scale distributions, local-scale habitat associations, and traits of the constituent species, we suggest that species in the former group have a more resource-conservative strategy compared to those in the latter group. Species within groups tended to have significantly greater niche overlap than expected by chance. Community-wide niche overlap in spatial and temporal niche axes was never smaller than expected by chance. Species-habitat associations were neither necessary nor sufficient preconditions for niche differences to be present. Our results suggest that this tropical dry-forest community consists of several tree species with broadly overlapping niches, and where significant niche differences do exist, they are not readily interpretable as evidence for niche differentiation. We argue, based on a survey of the literature, that many of the observed niche differences in tropical forests are more parsimoniously viewed as autecological differences between species that exist independently of interspecific interactions. In Chapter 4, we study the dynamics of the plant community in relation to environmental factors and biotic neighborhoods. We assess resources (precipitation, soil nutrients), environmental conditions (temperature), microhabitat conditions (topography), disturbances (fire) and conspecific and heterospecific plant neighborhoods to identify which of these best predicted mortality, recruitment and growth over a 24-yr study period. We fitted regression trees with recruitment, mortality or growth as the response variable and environmental and biotic neighborhood variables as predictors, with tree selection performed by a cross validation technique that accounted for the spatial and temporal autocorrelation present in the data. Niche specialists or species with abundances skewed towards particular habitats did not necessarily grow faster, recruit more or die less on “preferred” habitats. On the whole, spatial environmental factors were selected into models less frequently than either temporal environmental or neighborhood factors, and their effect sizes were also smaller. The first and second PCs of soil and topographic variables were selected into more models than the remaining PCs. While there was some evidence of conspecific negative density dependence, particularly on suppressing growth, density-dependent effects were on the whole weaker than temporal environmental factors and also decayed rapidly with distance. Positive density-dependence was prevalent, possibly resulting from dispersal limitation and facilitation. In some cases, initial increases in neighborhood density had positive effects that turned negative when densities further increased, suggesting non-linear responses. Precipitation increases largely had a positive, and minimum and maximum temperatures increases a negative, effect on recruitment, growth and survival, although responses were species-specific and, sometimes, non-linear. By far, the strongest and most consistent effects amongst all factors considered were that of fire, with recent fires having a strong and unidirectional, negative effect on all species for which fire was selected into a model. From a theoretical standpoint, there is limited support for the neutral perspective, given the strong and species-specific responses to spatial and temporal environmental variation and the presence of niche specificity at the local scale. Despite the evidence supporting the existence of niche specialization, it seems unlikely that this community is strongly stabilized by the presence of systematic niche differences. The net evidence on the structure and dynamics of this community point to what may be considered a null hypothesis, that is, species are responding individualistically – and independently of each other – to fluctuations in the environmental. It is hoped these results will provide information relevant to understanding, managing, and predicting the future of this ecosystem and contribute towards the development of general theories of plant community ecology.Ministry of Environment, Forests and Climate Change, the Department of Science and Technology, the Department of Biotechnolog

    Author Under Sail The Imagination of Jack London, 1893-1902

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    In Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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