1,721,017 research outputs found
Diversity of microbiomes associated with benthic invertebrates inhabiting Antarctic ecosystems
Il numero sempre più alto di studi condotti sui microbiomi ha evidenziato l’importanza che queste associazioni rivestono nello sviluppo, nella salute e nella fitness degli organismi con cui i microbiomi vivono associati. In ambienti estremi come l’Antartide, i microbiomi sembrano avere un’importanza cruciale nel creare interazioni fondamentali per l’adattamento dei loro ospiti. Gli obiettivi di questa tesi sono: i) studiare la biodiversità dei microbiomi associati a diversi invertebrati marini antartici, ii) esplorarne l’origine, confrontando i microbiomi associati agli organismi con le comunità batteriche che abitano nei sedimenti circostanti, e iii) verificare se i fattori ambientali svolgano un ruolo attivo nel modellare la loro composizione tassonomica. I risultati hanno mostrato che, nonostante i microbiomi associati ai policheti antartici (Leitoscoloplos geminus, Aphelocaeta palmeri, Aglaophamus trissophyllus) possano variare in modo significativo tra gli individui, è possibile individuare dei core, sia a livello intraspecifico sia interspecifico, che contribuiscono significativamente all'intera comunità batterica associata. I taxa batterici associati ai policheti sono completamente diversi da quelli presenti nei sedimenti circostanti, suggerendo una potenziale trasmissione verticale o diverse capacità adattative dei microbiomi ai due diversi “habitat”. Molteplici fattori (i.e., non solo fattori ambientali ma anche quelli biologici come lo stato fisiologico e le abitudini di alimentazione) influenzano, a diversi gradi, la composizione tassonomica dei microbiomi associati ai policheti antartici. Nella stella marina antartica Odontaster validus la posizione geografica è il principale fattore che spiega le differenze trovate nella composizione tassonomica dei microbiomi, sebbene siano state riscontrate alcune somiglianze tra individui raccolti in luoghi diversi, suggerendo la presenza di altri fattori in grado di selezionare comunità batteriche simili. La presenza esclusiva di batteri specifici associati a stelle marine che vivono in determinate aree suggerisce una potenziale trasmissione orizzontale dei microbiomi, probabilmente acquisiti attraverso diverse abitudini alimentari che le stelle marine hanno sviluppato nelle suddette aree. Questa tesi di dottorato fornisce nuove informazioni sui microbiomi antartici, evidenziando una forte variabilità della loro composizione e complessità delle relazioni con gli ospiti esaminati, potenzialmente dovute, oltre ai fattori ambientali, anche alle caratteristiche biologiche degli ospiti.Growing studies on host-associated microbiomes are highlighting the important role of microbes in the development, health and fitness of their hosts. This might be particularly true in remote and extreme environments, such as the Antarctic ecosystem, where the host and its microbiome could evolve together establishing peculiar and close interactions. This study aims: i) to investigate the biodiversity of microbiomes of different Antarctic invertebrates, ii) to explore the potential sources of the host-associated microorganisms by comparing them with microbial communities inhabiting the surrounding sediments, and iii) to verify the role of environmental setting in shaping their taxonomic composition. Results revealed that microbiomes of Antarctic polychaetes (Leitoscoloplos geminus, Aphelocaeta palmeri, Aglaophamus trissophyllus) showing significant variability among individuals, but that both intra-specific and inter-specific core microbiomes contribute for a significant fraction to the whole microbial assemblage. Bacteria associated with polychaetes were completely different from those in the surrounding sediments, suggesting a potential vertical transmission or the presence of different adaptative/selective conditions of the two “habitats”. Multiple factors (i.e., not only environmental factors but also biological ones such as physiological state and feeding habits) can influence to different extent the taxonomic composition of microbiomes associated with Antarctic polychaetes. In the Antarctic sea star Odontaster validus, the geographic location was identified as the main factor influencing the taxonomic composition of microbiomes, but this was not a general rule. In fact, high similarities were found among microbiomes of individuals collected in different locations, suggesting the presence of other drivers able to select similar microbial communities. The presence of exclusive bacterial families in sea-star microbiomes suggests a potential horizontal transmission of bacterial taxa, probably acquired through different feeding habits that the sea star might have developed in the different basins. This PhD thesis provided new information on Antarctic microbiomes, highlighting a strong variability of their composition and complexity of the relationships with the investigated hosts, potentially due to, besides environmental settings, also to hosts’ biological features
Going Beyond Counting First Authors in Author Co-citation Analysis
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
“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
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
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
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-wise bibliometric analysis based on entropy.
Author-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
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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