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    Ambulatory Arterial Stiffness Index (AASI) is Unable to Estimate Arterial Stiffness of Hypertensive Subjects: Role of Nocturnal Dipping of Blood Pressure.

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    BACKGROUND: Ambulatory Arterial Stiffness Index (AASI) has been proposed as an indirect and simpler method to estimate the Arterial Stiffness (AS). AASI, calculated from a set of data collected during a 24-hours ambulatory blood pressure monitoring (ABPM), is defined as 1 minus the regression slope of diastolic on systolic blood pressure (BP) values. For a given increase in diastolic BP, the increase in systolic BP is smaller in a compliant compared to a stiff artery; the stiffer the arterial tree, the closer AASI is to 1. AASI was demonstrated to predict cardiovascular mortality, cerebrovascular events and to be associated with target organ damage. Taking into account the almost complete absence of data regarding the ability of AASI to predict the different degree of AS when hypertensives are divided into four classes of dipping in relation to the extent of the nocturnal reduction of BP (extreme dippers, dippers, mild dippers and reverse dippers) aim to clarify the ability of AASI to estimate the different degree of AS of hypertensive subjects with different nocturnal BP profile and resulting in different extent of organ damage. MATERIALS AND METHODS: We enrolled 816 subjects (403 men and 413 women) with essential hypertension, referred to the U.O.C of Medicina Interna e Cardioangiologia of the University of Palermo; 173 subjects (71 men and 102 women, mean age 44.4 ± 14.6 years) without a history of hypertension were enrolled as controls. RESULTS: The analysis of data was performed by dividing the population into four categories in relation to the extent of the nocturnal decline of BP: 124 extreme dipper (mean age 54,8 ± 12,4 years, men 46.8 %); 287 dipper (mean age 55,9 ± 14,2 years, men 54,0 %); 271 mild dipper (mean age 61,5 ± 14,7 years, men 52,0 %); 134 reverse dipper (mean age 61,5 ± 14,7 years, men 33.6 %). The mean value of AASI was significantly higher for mild and reverse dippers versus control patients and versus the other categories of dipping. The multiple regression analysis with AASI as the dependent variable confirmed the significant association between AASI and nocturnal dip (p: 0.015). The Multinomial Logistic Regression Analysis, in which AASI values were adjusted for the main confounders (age, sex, Body Mass Index, 24h SBP, 24h DBP) showed that the association between AASI and dipping is maintained only for dipper and extreme dipper hypertensives, missing the significance for mild and reverse subjects. CONCLUSION: 1) AASI levels are associated with night-to-day BP ratio; 2) Lower levels of AASI are significantly associated to extreme dipper and dipper BP nocturnal profile when compared to healthy controls. 3) After correction for the major confounding factors, the association between AASI and the high-damaged class of hypertensive subjects with lower or no nocturnal fall of BP is lost. Our findings support the hypothesis that AASI is unable to estimate AS of older hypertensive subjects with a high burden of organ and vascular damage and several comorbidities, probably because the nocturnal reduction of BP is the main determinant of AASI, being more powerful than AS itself

    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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