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    PERBEDAAN PELEPASAN ION NIKEL DAN KROMIUM PADA BEBERAPA MEREK KAWAT STAINLESS STEEL YANG DIRENDAM DALAM ASAM CUKA

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    PERBEDAAN PELEPASAN ION NIKEL DAN KROMIUM PADA BEBERAPA MEREK KAWAT STAINLESS STEEL YANG DIRENDAM DALAM ASAM CUKA Meri Angelia Situmeang1), P. S. Anindita 1), Juliatri1) 1)Program Studi Pendidikan Dokter Gigi Fakultas Kedokteran UNSRAT Manado, 95115   ABSTRACT Wire is one of the important components in the orthodontic treatment. Orthodontic wire inside the oral cavity can trigger the release of metal ions when contact with an environment that has an acidic pH. One type of wire used in orthodontic treatment is stainless steel wire, because it has high strength and is affordable. Currently orthodontic stainless steel wire has been circulating in various brands. The purpose of this study was to determine the difference of nickel and chromium ion release on some brands of stainless steel orthodontic wire soaked in vinegar. This type of research is analytical research laboratory, performed in vitro using post test only control group design. The sample was 6 pieces of wire from 3 different brands and were divided into 2 groups: a control group soaked in saliva without the vinegar and the treatment group were soaked in saliva with vinegar. The release of ions was examined using Atomic Absorption Spectrophotometry (AAS). Data were analyzed using One Way Anova statistical test, Kruskal-Wallis, Independent T-test and Mann-Whitney. The results from this study showed significant ion release difference (p <0.05) of Ni and Cr in stainless steel orthodontic wires brands A, B, and C which soaked in vinegar. Key words : stainless steel orthodontic wires, nickel and chromium ions, vinegar. ABSTRAK Kawat merupakan salah satu komponen penting dalam perawatan ortodonti. Didalam rongga mulut kawat ortodonti dapat memicu pelepasan ion logam jika berkontak dengan lingkungan yang memiliki pH asam. Salah satu jenis kawat yang digunakan dalam perawatan ortodonti ialah kawat stainless steel, karena mempunyai kekuatan yang tinggi dan ekonomis. Saat ini kawat ortodonti stainless steel telah beredar dalam berbagai macam merek. Tujuan dari penelitian ini ialah untuk melihat perbedaan pelepasan ion nikel dan kromuim pada beberapa merek kawat ortodonti stainless steel yang direndam dalam asam cuka.Jenis penelitian ini ialah penelitian analitik laboratorik, yang dilakukan secara in vitro menggunakan rancangan post test only control group design. Sampel yang digunakan berjumlah 6 buah kawat dari 3 merek yang berbeda yang dibagi menjadi 2 kelompok, yaitu kelompok kontrol yang direndam dalam saliva tanpa asam cuka dan kelompok perlakuan yang direndam dalam saliva dengan asam cuka. Pelepasan ion kemudian diuji menggunakan alat Spektrofotometri Serapan Atom (SSA). Data hasil penelitian selanjutnya dianalisis menggunakan uji statistik One Way Anova, Kruskal-Wallis, Independent T-Test, dan Mann-Whitney. Hasil penelitian menunjukkan adanya perbedaan pelepasan ion Ni dan Cr yang bermakna (p<0,05) pada kawat ortodonti stainless steel merek A, B, dan C yang direndam dalam asam cuka. Kata kunci: kawat ortodonti stainless steel, ion nikel dan kromium, asam cuka

    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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