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Variación ecogeográfica de la forma y tamaño del cráneo en tres especies de murciélagos insectívoros en Cuba / Ecogeographical variation in cranial shape and size of three insectivorous bats in Cuba
No full textResumen: Se estudiaron los patrones de variación ecogeográfica en Cuba de tres especies de murciélagos insectívoros: Molossus molossus (familia Molossidae), Eptesicus fuscus (Vespertilionidae) y Macrotus waterhousei (Phyllostomidae). Se emplearon puntos anatómicos claves y puntos deslizantes para describir tres vistas del cráneo y la mandíbula en vista lateral. Se comparó el tamaño y la forma del cráneo entre sexos y entre regiones usando métodos de morfometría geométrica. Para cada localidad se obtuvieron variables ambientales y la posición geográfica. El dimorfismo sexual en forma, así como la variación regional y la asociación entre la variación morfológica con la posición geográfica y variables ambientales fueron analizados mediante técnicas de estadística multivariada. En las tres especies de murciélagos existe dimorfismo sexual en la forma, y los machos tienden a presentar cráneos y mandíbulas más robustas. Se encontró variación significativa en la forma del cráneo entre regiones, con una tendencia a una mayor diferenciación fenotípica en los individuos de la Isla de la Juventud. No obstante, con excepción de M. waterhousei, el tamaño del cráneo no estuvo asociado con la longitud geográfica y la similitud en la forma del cráneo no mostró relación con la distancia que separa a las poblaciones. Esto sugiere que la variación morfológica muestra poca relación con la posición geográfica. Sin embargo, los resultados de la regresión de mínimos cuadrados parciales mostraron que existe alta correlación entre las variables ambientales y la forma del cráneo. En todas las especies el vector ambiental describe un gradiente relacionado positivamente con la precipitación anual y negativamente con la temperatura media anual. Los resultados de este estudio sugieren que las condiciones ambientales podrían ser parcialmente responsables de la variación observada en la forma del cráneo en las tres especies de murciélagos.
Palabras clave: Divergencia fenotípica, Eptesicus fuscus, gradientes ambientales, Macrotus waterhousei, Molossus molossus, morfometría geométrica.
Abstract: The patterns of ecogeographical variation in skull morphometry of three Cuban insectivorous bat species: Molossus molossus (family Molossidae), Eptesicus fuscus (Vespertilionidae) and Macrotus waterhousei (Phyllostomidae) were studied. Landmarks and semi-landmarks were used to describe three views of the skull and the mandible in lateral view. Skull size and shape were compared between sexes and among regions, using landmark-based geometric morphometric methods. Geographical position and environmental variables were obtained for each locality. Univariate and multivariate analyses of variance as well as correlations and partial least squares regressions were applied to test sexual dimorphism and regional variation and the relationship between geographic longitude and environmental variables on skull shape and size. Statistically significant sexual dimorphism in cranial shape was found in the three species, the males had more robust cranium. Morphological differences in skull shape and size were found among geographical regions in the three species, the individuals of Isla de la Juventud tend to be more phenotypically differentiated compared to main Cuban island. With the exception of M. waterhousei, the skull size is not related to longitude, and the similarity in shape is not correlated with minimal geographic distances between populations. These suggest that observed variation do not show association with to geographic position. However, the results of the partial least squares regressions showed that there is a high correlation between the skull shape and environmental variables. In the studied bats, the environmental vector described a gradient related positively with annual precipitation and negatively with annual mean temperature. The results suggest that environmental pressures could be at least partially responsible on cranial shape variation observed.
Keywords: Environmental gradients, Eptesicus fuscus, geometric morphometric, phenotypic divergence, Macrotus waterhousei, Molossus molossus.
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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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