1,720,954 research outputs found
Análisis espacial y corológico de las angiospermas en el bosque tropical estacionalmente seco: la Depresión del Balsas como caso de estudio
Get PDFLa regionalización biogeográfica es fundamental para entender la distribución espacial de la diversidad biológica y para identificar áreas importantes por su riqueza de especies y endemismos, por ejemplo, en el Bosque Tropical Estacionalmente Seco (BTES) de la Depresión del Balsas (DB), México. Las herramientas utilizadas en la regionalización permiten identificar conjuntos de especies con la misma distribución o corotipos, y son un recurso ideal para reconocer categorías corológicas (unidades biogeográficas). En México, la delimitación y regionalización, considerando tanto aspectos fisiográficos como florísticos, han sido poco explorados, por lo que surge la necesidad de formular estrategias metodológicas que permitan definir, con mayor precisión y replicabilidad, los límites geográficos de regiones de interés, a partir de análisis espaciales. En este contexto, en los capítulos que integran esta tesis se hace una propuesta metodológica con el fin de homogenizar el proceso de regionalización, haciendo uso de información contenida en bases de datos y recursos cartográficos disponibles en línea, como los datos de ocurrencia de las especies o variables fisiográficas y ambientales.
En el Capítulo I se presenta una introducción general sobre el marco conceptual de la regionalización biogeográfica y los enfoques desde la cual se ha abordado, planteando, además, la problemática de la regionalización en México, considerando como caso de estudio la DB. En el Capítulo II se describe brevemente el área de estudio, en la cual se llevaron a cabo los análisis biogeográficos.
Con la finalidad de circunscribir el área de estudio, en el Capítulo III se presenta una propuesta de delimitación geográfica y florística de la DB, basada en un método sistemático, considerando análisis de información cartográfica y análisis estadísticos de los datos florísticos disponibles para la región. Como resultado se obtuvo que la DB tiene una extensión de 178,393 km².
Una vez definidos los límites geográficos de la provincia DB, en el Capítulo IV se propuso una regionalización biogeográfica del BTES en la DB, al identificar distritos al interior de la provincia mediante el análisis de los patrones espaciales de la riqueza de especies de la familia Asteraceae. Los análisis espaciales permitieron delimitar dos regiones florísticas (oriental y occidental). Esta última región muestra mayor heterogeneidad en su composición de especies por celda. Sin embargo, la región Oriental, aunque más homogénea en su composición florística por celda, registró un mayor número de especies restringidas.Biogeographic regionalization is essential to understand the spatial distribution of biological diversity and to identify important areas due to their species richness and endemism, such as the Seasonally Dry Tropical Forest (SDTF) in the Balsas Depression (BD). The tools used in biogeographic regionalization allow the identification of sets of species with the same distribution or chorotypes and are the ideal resource for recognizing chorological categories (biogeographic units). In Mexico, the delimitation and regionalization, considering both physiographic and floristic aspects, has been little explored; for this reason, there is a need to formulate methodological strategies that allow defining with greater precision and replicability the geographical limits of regions of interest based on spatial analyses. In this context, in the chapters of this thesis, a methodological proposal is made in order to homogenize the regionalization process, making use of information contained in databases and cartographic resources available online, such as species occurrence records, physiographic and environmental variables. Chapter I includes a general introduction, in which the conceptual framework of biogeographic regionalization and the approaches to address it are developed, also pointing out the problem of regionalization in Mexico, considering the BD as a case study. Chapter II briefly describes the study area on which the biogeographic analyzes were carried out.
In order to circumscribe the study area, Chapter III comprises a proposal for the geographical and floristic delimitation of the BD based on a systematic method, considering analysis of cartographic information and statistical analysis of the floristic data available for the region. As a result, it was achieved that the BD has an extension of 178,393 km².
Once the geographical limits of the BD province defined, through analysis of spatial patterns of the species richness of the Asteraceae family in Chapter IV the districts within the province were identified. In this way a biogeographic regionalization of the SDTF in the BD is proposed. The spatial analyzes allowed to delimit two floristic regions (eastern and western). The Western region shows greater floristic heterogeneity in its composition of species per grid cell. However, the Eastern region, although more homogeneous in its floristic composition per grid cell, recorded a higher number of restricted species
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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