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    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

    Transporte e sorção do imazapic em solos cultivados com cana-de-açúcar

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    Os herbicidas compõem uma parte importante dos agrotóxicos, englobando em torno de 45% de todos os pesticidas usados na agricultura. Os herbicidas podem ser usados em pré ou pós-emergência no controle de plantas invasoras em diversas culturas agrícolas, sobretudo nas monoculturas como soja, milho e cana-de-açúcar. A cultura da cana-de-açúcar é produzida em sua maior parte no sudeste do país, englobando cerca de 85% da produção, enquanto o Nordeste compreende em torno de 13% da produção do país. Em Pernambuco, as regiões da mata sul e norte são as produtoras de cana no estado, as características climáticas (clima quente e úmido) favorecem seu cultivo. O herbicida Imazapic é usado em contato direto com o solo como pré-emergente. O trabalho teve o objetivo de avaliar a interação do herbicida Imazapic no solo, através de ensaios de deslocamentos miscíveis em colunas de solo, uma vez que a contaminação do solo e água com agrotóxicos é recorrente devido à alta mobilidade, gerando grande preocupação ambiental. Foram realizados estudos em colunas de solo com um ARGISSOLO AMARELO Distrófico (AAd) e um LATOSSOLO VERMELHO-AMARELO Distrófico (LVAd) da mata norte do estado de Pernambuco cultivado com cana-de-açúcar. A avaliação da mobilidade do solo foi baseada nas diferentes características físicas, químicas e mineralógicas do AAd e do LVAd. A concentração de Imazapic foi determinada por cromatografia líquida de alta eficiência (CLAE). A avaliação dos mecanismos envolvidos no transporte e a determinação dos parâmetros hidrodispersivos da curva de eluição do Brometo de Potássio (KBr) se ajustou bem ao modelo CDE (Convecção – Dispersão). As curvas de eluição para o Imazapic foram ajustadas utilizando o modelo CDE a 2 Sítios de Sorção por intermédio do programa CXTFIT 2.0. O coeficiente de partição Kd para o LVAd apresentou valor médio de 0,18 L kg-1 enquanto para o AAd apresentou valor médio de 0,084 L kg-1 com valores médios do índice GUS de 6,2 e 6,8 respectivamente, confirmando o alto potencial de lixiviação da molécula do Imazapic nos solos estudados. A maior interação da molécula de Imazapic se deu com o LVAd devido a fatores físico-químicos do solo como maior teor de argila (30%) e maiores concentrações de Fed e Feo, retardando assim o potencial de lixiviação do herbicida nessa classe de solo e consequentemente as implicações de contaminação dos recursos hídricos.Herbicides compose an important part of pesticides, comprising around 45% of all pesticides used in agriculture. Herbicides can be used pre or post-emergence in the control of weeds in various crops, particularly in crops like soybean, corn and sugarcane. The culture of sugarcane is produced mostly in the Southeast of Brazil, covering about 85% of production, while the Northeast comprises around 13% of production in the country. In Pernambuco, the regions of the south and north woods are the cane producers in the state, the climatic conditions (hot and humid) favor its cultivation. The Imazapic herbicide is used in direct contact with the ground as a pre-emergent. The work was to evaluate the interaction of Imazapic herbicide in soil using miscible displacement tests in soil columns, since the soil and water with pesticides recurs due to high mobility, creating major environmental concern. Studies were carried out in soil columns with a YELLOW ultisol Dystrophic (AAd) and Oxisol dystrophic (LVAd) of the north woods of Pernambuco state cultivated with sugarcane. The evaluation of soil mobility was based on different physical, chemical and mineralogical for AAd and LVAd. Imazapic concentration was determined by high-performance liquid chromatography (HPLC). A review of the mechanisms involved in the transport and determination of hydrodispersive parameters of Bromide Potassium breakthrough curves (KBr) fitted well the CDE model (Convection - Dispersion). The breakthrough curves for the Imazapic were adjusted using the two sites nonequilibrium model (CDE-2S) through the CXTFIT 2.0 program. The partition coefficient Kd for LVAd averaged 0.18 kg L-1 while for the AAd averaged 0.084 kg L-1, with average values of GUS index 6.2 and 6.8 respectively, confirming high leaching potential of the Imazapic molecule in the soils. The greater interaction of Imazapic molecule occurred with the LVAd due to soil physicochemical factors as higher clay content (30%) and higher concentrations of Fed and Feo, thus slowing the potential leaching of the herbicide in this class of soil and consequently the contamination of water resources implications

    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

    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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