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Development of a trophic model of the ecosystem of Macrocystis pyrifera on Natividad Island.
No full textActualmente, los ecosistemas marinos están sujetos a cambios antropogénicos y ambientales que afectan su estructura y función. Las pesquerías, es una de las principales perturbaciones antropogénicos a la que están sujetos los ecosistemas globalmente. La principal repercusión de la pesquería sobre los ecosistemas es una fuerte disminución de la biomasa y densidad de algunas de sus especies que incluso pueden llegar a desaparecer. Los modelos ecosistémicos, basados en datos de monitoreo para diseñar experimentos, es una alternativa que ayuda a entender la estructura y funcionamiento de las comunidades naturales y a diseñar mejores medidas de manejo y conservación. El objetivo de este trabajo es conocer la estructura del ecosistema de sargazo gigante de Isla Natividad en la costa del Pacífico de Baja California y evaluar diferentes escenarios de mortalidad por pesca que puedan afectar al ecosistema en general y a los grupos funcionales que lo forman. Para conocer la estructura del ecosistema de sargazo gigante de Isla Natividad se generó un modelo Ecopath con Ecosim, utilizando datos de monitoreos. Se clasificaron 40 grupos funcionales incluyendo vertebrados, invertebrados y detritos. Los valores de biomasa se obtuvieron de un gran esfuerzo de monitoreos in situ y los valores de producción/biomasa y consumo de biomasa se obtuvieron de una intensa búsqueda bibliográfica. Se generaron 9 escenarios para predecir cómo va a responder el ecosistema a cambios en la mortalidad por pesca y en el tiempo; se combinaron predicciones temporales (10, 20 y 30 años) y cambios porcentuales de mortalidad por pesca (aumento 10%, disminución 10% y constante). Se desarrolló el modelo satisfactoriamente lo que permitió conocer la estructura del ecosistema de Isla Natividad, así como las interacciones entre los grupos funcionales y las flotas pesqueras. Todos los escenarios predictivos muestran una disminución total de biomasa en el ecosistema. Sin embargo, no todos los grupos funcionales responden de la misma forma ya que el aumento de la pesquería favorece al aumento de la biomasa de algunos, pero no de otros. Además, la biomasa total del ecosistema se ve directamente afectada por la biomasa del alga estructuradora Macrocystis pyrifera, cuya presencia hace que el ecosistema pierda menor biomasa a pesar del aumento de la mortalidad por pesca.Marine ecosystems are subject to anthropogenic and environmental changes affecting both their structure and function. Fisheries entail one of the major anthropogenic disturbances to many ecosystems on a global scale. Many fished marine ecosystems show trending reductions in biomass and density, resulting in the disappearance of some species over time. The construction of ecosystem models using monitoring data allows for the exploration of the structure and function of ecosystems under different scenarios, allowing for the improved design of management and conservation tools. In this study, I determined the structure of the macroalgal ecosystem of Isla Natividad, Baja California Sur, Mexico, under different fishing mortality scenarios using an Ecopath model with Ecosim model based on in situ monitoring data. Forty functional groups were classified, including vertebrates, invertebrates and detritus. Biomass values were obtained from a large in situ monitoring effort; and the values of production / biomass and biomass consumption were obtained from the literature. To predict how the ecosystem would respond to changes in fishing mortality and over time, 9 scenarios were generated, or to 10, 20 and 30 years, under present fishing mortality, a 10% increase and a 10% decrease. Under all predicted scenarios, the ecosystem model showed a decline in total biomass. Not all functional groups responded in the same way as the biomass of some groups was favored by increased fishing mortality but not others. In addition, the total biomass of the ecosystem was directly affected by the biomass of the structural alga Macrocystis pyrifera, whose presence appears to buffer the ecosystem against biomass loss. This study highlights the importance of looking at functional groups of the ecosystem separately, as they can respond quite differently under the same scenario
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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