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    Respiración Foliar de Eucalyptus globulus labill. (MYTACEAE) y Polylepis racemosa Ruiz & Pav. (Rosaceae) en el Valle del Cusco

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    La investigación se realizó en cinco localidades del Valle del Cusco ubicadas a diferentes latitudes, denominadas: Chocco, Pumamarca, Sacsayhuamán, Tambomachay y Tancarpata durante la época de sequía en el año 2012; con el objeto de evaluar el flujo de CO2 foliar y la densidad estomática en la especie introducida Eucalyptus g/obu/us Labill y la especie nativa Po/y/e pis racemosa Ruiz & Pav. Ambas utilizadas para forestación y reforestación respectivamente; luego se comparó el flujo de CO2 foliar según la localidad y los estratos en el dosel en cada especie; se estableció variaciones diurnas del flujo de CO2 y se observó la relación del flujo de CO2 con la temperatura ambiental, biomasa foliar, área foliar específica y densidad estomática. En E. globulus se trabajó con hojas verdaderas para el estrato inferior y con filodios en el estrato superior. Para la medida de la emisión de CO2 foliar de ambas especies, las ramas colectadas se expusieron al sol por 30 minutos y luego se sometieron a oscuridad por 30 minutos antes de cada medida con el analizador de gases infrarrojo EGM-4. Para la densidad estomática de E. globulus se utilizó la técnica de improntas y para P. racemosa el ablandado de epidermis con ácido nítrico al 10%; luego de estos tratamientos las impresiones foliares se observaron en un microscopio a 400X. Los filodios del estrato superior de E. globulus presentaron un flujo de CO2 foliar entre 0.71 a 1.35 µmolCO2m-2s-1 y entre 0.81 a 1.08 µmolCO2m-2s-1 en las hojas del estrato inferior del dosel. No se encontró diferencia significativa en los flujos de CO2 entre localidades a excepción de Chocco ni por la posición en el dosel. En el estrato superior de P. racemosa, el flujo de CO2 foliar osciló entre 0.59 a 1.05 µmolCO2m-2s-1 y entre 0.51 a 0.95 µmolCO2m-2s-1 para el estrato inferior del dosel. No se encontró diferencia significativa en los flujos de CO2 según la localidad y posición en el dosel. Las variaciones diurnas del flujo de CO2 fue alta entre las 11 :00 y 15:00 horas para E. globulus y baja a las 13:00 horas. En P. racemosa fue alta entre las 11 :00 a 12:00 horas y baja a las 13 horas; debiéndose al aumento de temperatura que se presenta a esas horas mientras que la disminución significativa a las 13:00 horas se debió a la mayor insolación que se presenta y que favorece al proceso de fotosíntesis. También se comprobó que el flujo de CO2 está influenciado directamente con la temperatura ambiental y la biomasa foliar, sin embargo no se encontró relación con el área foliar específica. Las hojas de E. globulus son anfiestomáticas con estomas de tipo Anomocítico. La densidad estomática de los filodios del estrato superior oscilaron entre 21.70 a 62.50 estomas.mm-2 para la superficie adaxial y entre 111.65 a 150.28 estomas.mm-2 para la superficie abaxial. La densidad estomática de las hojas de estrato inferior oscilaron entre 16,91 a 23.48 estomas.mm-2 para la superficie adaxial y entre 111.65 a 150.28 estomas. mm-2 para la superficie abaxial. No se encontró diferencia significativa de densidad estomática por la localidad y por la sección foliar. Se encontró diferencia significativa por la posición en el dosel y por superficies foliares. Se observó una relación positiva entre la densidad estomática y el flujo de CO2 en ambos estratos del dosel de E. globulus. La relación de la densidad estomática con el área foliar es positiva en el estrato inferior de E. globulus y negativa en el estrato superior. Las hojas de P. racemosa son hipoestomáticas con estomas de tipo Anomocítico con células subsidiarias papilosas. La densidad estomática de P. racemosa es 14.69 a 15.65 estomas.mm-2 para el estrato superior del dosel y entre 9.96 a 10.28 estomas.mm-2 para el estrato inferior. No se encontró diferencia significativa de la densidad estomática promedio por localidades y por sección foliar. Existe diferencia significativa por la posición en el dosel. No se observó relación entre la densidad estomática y el 'flujo de CO2 en los estratos inferior y superior de P. racemosa. La relación de la densidad estomática con el área foliar fue positivo en ambos estratos.Tesi

    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

    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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