1,720,954 research outputs found
Agronomic and ecological responses of a mixture of tropical forage grasses in pastures
No full textA demanda crescente da população mundial torna necessário o aumento da produção de alimentos de forma sustentável, preservando o meio ambiente. Nesse contexto, as pastagens multiespecíficas assumem papel de destaque, uma vez que o incremento da biodiversidade vegetal permite diversificação de espécies, otimização da utilização dos recursos disponíveis, estabilização da produção primária, além de assegurarem diversos serviços ambientais importantes. Essa é uma realidade em regiões de clima temperado, mas ainda muito pouco desenvolvida e estudada em regiões de clima tropical. O objetivo deste estudo foi avaliar as respostas agronômicas de uma associação composta por três gramíneas forrageiras tropicas, caracterizando uma pastagem multiespecífica. O potencial produtivo da associação foi comparado com a produção das três gramíneas forrageiras em monocultivo. As respostas agronômicas da associação foram interpretadas a partir dos mecanismos da biodiversidade (diferenciação de nichos e “efeito de seleção”). As variáveis resposta avaliadas foram: índice de área foliar, interceptação luminosa, densidade populacional de perfilhos, taxa de acúmulo de forragem, massa de forragem e composição botânica e morfológica da massa de forragem. A pesquisa foi realizada em área experimental do Departamento de Zootecnia na ESALQ/USP, Piracicaba, São Paulo, entre janeiro de 2020 e março de 2021. Os tratamentos corresponderam a três espécies de gramíneas forrageiras tropicais (Andropogon gayanus cv. Planaltina, Brachiaria brizantha cv. BRS Piatã e Panicum maximum cv. Massai) cultivadas em monocultivo e em associação, e foram alocados às unidades experimentais segundo delineamento de blocos completos casualizados com quatro repetições. O regime de desfolhação foi comum a todos os tratamentos e caracterizado por altura pré-corte de 35 cm e altura pós-corte de 17,5 cm. De forma geral, as respostas agronômicas da associação foram similares aos dois capins de maior potencial produtivo no monocultivo. A partir dos resultados, é possível inferir que ambos os efeitos de seleção e complementariedade entre as espécies na mistura tenham influenciado as respostas da associação. Apesar da predominância de uma espécie na composição botânica da associação (Panicum maximum cv. Massai), não foi encontrado evidência que indique a possibilidade de uma transição para condição de monocultivo.The growing demand of the world population causes the need to increase food production in a sustainable way, preserving the environment. In this context, multispecific pastures play a relevant role, since increased biodiversity allows species diversity, resource use optimization, primary production stabilization as well as several important environmental services. This is well known and studied in temperate climate regions, but still very little developed in tropical areas of the globe. The objective of this study was to evaluate the agronomic responses of an association comprised of three tropical forage grass species forming a multispecific pasture. The productive potential of the association was compared to the production of the three grass species in monoculture. The agronomic responses of the association were interpreted using biodiversity mechanisms (niche differentiation and selection effect). The response variables studied were: sward leaf area index, canopy light interception, tiller population density, herbage accumulation rate, herbage mass and its botanical and morphological composition. The experiment was carried out at Animal Science Department, ESALQ/USP, Piracicaba, São Paulo, from January 2020 until March 2021. Treatments corresponded to three tropical forage grass species (Andropogon gayanus cv. Planaltina, Brachiaria brizantha cv. BRS Piatã e Panicum maximum cv. Massai) cultivated as monoculture or in association, and were allocated to experimental units according to a complete randomized block design with four replications. The defoliation regime was common to all treatments and corresponded to intermittent cutting characterized by pre-cutting height of 35 cm and post- cutting height of 17.5 cm. Overall, the agronomic responses of the association were similar to those of the two most productive grass species cultivated as monoculture. From the results, it is possible to infer that both selection and complementary effects among species influenced the responses of the association. In spite of the predominance of one species in the association (Panicum maximum cv. Massai), there was no evidence indicating the possibility of a transition to a monocultive condition
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
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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn 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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