1,720,981 research outputs found
Sobre a organização das espécies nas comunidades: uma abordagem global com peixes recifais
Get PDFDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-Graduação em Ecologia, Florianópolis, 2011A distribuição de espécies nas comunidades é mais influenciada por filtros locais derivados de interações de espécies ou fatores históricos e processos biogeográficos em escala regional? Que contribuição da riqueza regional seria esperada na compactação de espécies por unidade de área? Essas relações permanecem constantes em escalas espaciais hierárquicas de transectos a regiões? Num gradiente crescente de riqueza regional, a importância de fatores determinísticos vs. estocásticos nas regras de montagem (assembly rules) das comunidades locais se alterna? Categorizar espécies num conjunto reduzido de grupos funcionais muda os padrões supracitados? Por quê? Quão ampla deve ser a aplicabilidade de todos esses padrões entre diferentes grupos de organismos? Nesta dissertação, direciono respostas e discussões a esses desafios utilizando, provavelmente, o banco de dados quantitativo mais extenso geograficamente já compilado para peixes recifais - o grupo de vertebrados mais rico do planeta. Independentemente, eu e os colaboradores desse trabalho realizamos transectos padronizados em 20x2m=40m2 paralelos ao recife até 30m de profundidade - um esforço total de 5.916 transectos. O escopo geográfico abrange 103 sítios distribuídos em 17 localidades englobadas em seis grandes regiões biogeográficas marinhas tropicais: 1) Caribe (Belize, Cuba e Bahamas); 2) Atlântico Sul Ocidental (sul, sudeste e nordeste do Brasil); 3) ilhas oceânicas do Atlântico Sul Ocidental (Arquipélagos de São Pedro e São Paulo, Fernando de Noronha e Trindade e Martim Vaz); 4) Atlântico Oriental (São Tomé e Cabo Verde); 5) Pacífico Oriental (México e ilha de Malpelo); 6) Pacífico Sul (Nova Caledônia, Tonga, Fiji e Polinésia Francesa). 989 espécies pertencentes a 301 gêneros e 83 famílias foram registradas. Através de regressões entre riqueza local e regional em três escalas espaciais hierárquicas observei que a riqueza local aumenta linearmente com o aumento da riqueza regional tanto em termos taxonômicos (riqueza de espécies) como funcionais (riqueza de grupos funcionais). Isso indica que processos atuando na escala regional (e.g., especiação, extinção, dispersão) devem ser mais influentes do que processos locais (e.g., competição, predação) na composição local de comunidades. O aumento da riqueza regional de peixes em função do aumento da riqueza regional de corais pode ser um indicativo de que diversidade gera diversidade em termos de riqueza de nicho. Nas 17 localidades, a dissimilaridade média entre amostras, medida através da distância de Jaccard, não diferiu do esperado ao acaso, i.e., gerado por um modelo nulo que simulou colonizações no espaço. Esse padrão, observado em termos taxonômicos e funcionais, sugere que as espécies e grupos funcionais se distribuem de maneira estocástica na escala local da comunidade, entretanto outras abordagens nulas devem ser adotadas para confirmação do padrão encontrado. Meus resultados estão de acordo com a recente mudança de paradigma na Ecologia de Comunidades na qual as atenções voltaram-se para padrões regionais e macroecológicos ao invés de processos locais no entendimento da composição local da biodiversidade, ainda que tais regras sejam contingentes ao grupo de organismos analisado. Acredito que os resultados aqui apresentados possam refletir um padrão geral para metacomunidades ricas e relativamente abertas, nas quais comunidades locais são altamente influenciadas por processos regionais e talvez montadas ao acaso
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
- …
