1,720,957 research outputs found

    Study of senescence and possible mechanisms involved in arsenic-induced carcinogenesis in humans

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    Arsenic (As) induces various patho-physiological outcomes in humans like cancers including skin cancers, peripheral neuropathy (PN) and respiratory diseases. Though reports have shown that arsenic induced senescence (AIS) in vitro; population based studies on AIS and epigenetic regulation of AIS contributing to As-induced diseases remains unexplored. We investigated AIS, senescence-associated secretory phenotype (SASP) markers, telomere length alteration, epigenetic regulation involving altered senescence associated miRNA (SAmiRs) expression in arsenic exposed individuals with characteristic skin lesions and peripheral neuropathy. We also made an attempt to check the genetic damage, overall health status and telomere length in arsenic exposed children. Exposure assessment was done from drinking water and urine collected from arsenic exposed (N=120) and unexposed (N=60) individuals recruited from West Bengal, India. Senescence and telomere length alteration was evaluated using SA β-gal activity, ELISA and quantification of senescence proteins, alternative lengthening of telomere (ALT) associated proteins and telomerase activity. Relative telomere length (RTL) and SA-miRs in AIS was determined by qPCR. The downstream molecule of the miRNA associated with As-induced PN was quantified by immuoblotting. In vitro studies were conducted with sodium arsenite exposed HEK 293 cells, to revalidate the observations. As-exposed individuals exhibited significantly increased senescent cells, upregulated senescence inducers, p53/p21 and SASP markers when compared to unexposed controls. Asexposed skin lesion group showed significantly increased RTL, which was telomeraseindependent but exhibited an over-expression of ALT associated proteins. All the SA-miRs assessed were upregulated in the As-exposed compared to controls, specifically miR-29a. Further analysis found that highest expression of miR29a and peripheral myelin protein 22 (PMP22), a direct target of miR 29a, was among As-exposed individuals with PN. Analyzing other intermediate players regulating PMP22 expression revealed up-regulation of β-catenin and down-regulation of GSK-3β. Our findings suggest that up-regulation of β-catenin, possibly by miR29a mediated negative regulation of β-catenin inhibitors, may play a predominant role in expression of PMP22 which leads to formation of aggresomes. Further work to validate this mechanism is in process in vitro. Arsenic exposed children showed considerable genetic damage as measured by micronucleus assay in the three cell types and also adverse health outcomes like decreased haemoglobin content and gastritis. Telomere length of arsenic exposed children was slightly elevated though it did not reach the significance level. Our findings suggest that arsenic exposure induces senescence in vivo and telomeraseindependent elongation of telomere length is strictly associated with As-induced skin lesions in adults. Epigenetically, arsenic alters the expression of SA-miRs and the mir29a/beta catenin/PMP22 axis might be responsible for arsenic induced PN. However, in children, the telomere length increase and genetic damage in the three cell types and adverse health outcomes suggested that children are equally at danger of arsenic poisoning

    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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