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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
Chemical composition of scheelite and its application as an indicator mineral
No full textTitre de l'écran-titre (visionné le 19 juin 2023)La scheelite est un minéral de tungstène (CaWO₄) qui est présent dans plusieurs gisements magmatiques-hydrothermaux et qui est associé temporellement et spatialement à l'or dans certains gisements d'or orogéniques dans le monde. Comme la scheelite est un minéral résistant et lourd, et qu'elle est facile à identifier en raison de sa propriété luminescente, sa présence dans les sédiments a été utilisée comme outil pour cibler les gisements de tungstène et, plus récemment, les gisements d'or orogéniques dans les régions où l'exposition du substratum rocheux est rare. La scheelite contient certains éléments traces clés (Sr, Mo, REE, Na, As) dont la distribution et la concentration sont contrôlées par le contexte géologique dans lequel la scheelite s'est formée. Par conséquent, comprendre les facteurs qui contrôlent la distribution des éléments traces dans la scheelite permet d'utiliser la composition de la scheelite pour cibler les gisements minéraux. Cette thèse de doctorat étudie la composition en éléments traces de la scheelite associée aux principaux gisements magmatiques-hydrothermaux contenant de la scheelite, tels que les skarns oxydés et réduits, les veines de quartz/greisen à Sn-W, les porphyres à W-Mo et les systèmes aurifères liés à des intrusions réduites, afin d'identifier les principaux facteurs qui contrôlent la distribution des éléments mineurs et traces dans la scheelite. Ces nouvelles données sont combinées avec les données de la littérature sur les gisements d'or orogéniques contenant de la scheelite et étudiées à l'aide de l'analyse discriminante des moindres carrés partiels (PLS-DA) pour trouver les variables chimiques qui permettent de distinguer la scheelite des différents types de gisement et de les utiliser pour cibler les gisements de minerai d'or et de tungstène. Les résultats montrent que la fugacité de l'oxygène, la composition des fluides et des intrusions, les minéraux co-précipités et la salinité des fluides sont les principaux paramètres qui contrôlent l'incorporation des éléments traces dans la scheelite provenant de gisements magmatiques-hydrothermaux. Les résultats de l'analyse PLS-DA montrent que les teneurs élevées en Mo, As et V dans la scheelite sont caractéristiques des dépôts magmatiques-hydrothermaux formés sous une fugacité élevée de l'oxygène, tels que les skarns oxydés, tandis que les teneurs élevées en Nb, Mn, Y et U sont caractéristiques de la scheelite formée dans des conditions réduites, qui sont généralement associées aux skarns réduits et aux veines de quartz/greisen à Sn-W. La scheelite provenant de gisements d'or orogéniques présente une anomalie positive prédominante en Eu, une teneur élevée en Sr, et de faibles teneurs en Mo, Mn et Nb, ce qui la distingue de la scheelite liée aux gisements magmatiques-hydrothermaux. De telles différences permettent de discriminer la scheelite associée à l'or orogénique de celles des dépôts magmatiques-hydrothermaux. En plus de l'analyse PLS-DA, deux modèles de Random Forest sont proposés pour évaluer la source de la scheelite et la fertilité en or des gisements d'or orogéniques contenant de la scheelite. La grande justesse obtenue par les deux modèles renforce l'utilisation des éléments traces dans la scheelite non seulement comme un outil robuste et efficace pour cibler les gisements contenant de la scheelite, mais aussi pour évaluer la fertilité des gisements d'or orogéniques contenant de la scheelite.Scheelite is a tungsten mineral (CaWO₄) that is present in several magmatic-hydrothermal deposits and occurs temporally and spatially associated with Au in some orogenic Au deposits worldwide. Because scheelite is a resistant, heavy mineral, and easy to identify due to luminescence propriety, its occurrence in unconsolidated sediments has been used as a tool for targeting tungsten and orogenic Au deposits in areas where the bedrock exposition is rare. Scheelite hosts some key trace elements (Sr, Mo, REE, Na, As) those distribution and concentration are controlled by the geological settings where scheelite formed. Therefore, understanding the factors that control the distribution of trace elements in scheelite provides insights for using scheelite composition to target mineral deposits. This PhD thesis investigates the trace element composition of scheelite associated with the main scheelite-bearing magmatic-hydrothermal deposits such as oxidized and reduced skarns, quartz-vein/greisen Sn-W, porphyry W-Mo and reduced intrusion-related gold systems (RIRGS) to identify the principal factors that control the distribution of minor and trace elements in scheelite. This new data is combined with literature data of scheelite-bearing orogenic Au deposits and investigated using partial least square-discriminant analysis (PLS-DA) to find the chemical variables that allow for discriminating scheelite from different deposit types and use these to target for Au and W ore deposits. The results show that oxygen fugacity, fluid and intrusion compositions, co-precipitated minerals and fluid salinity are the main parameters that control the incorporation of trace elements in scheelite from magmatic-hydrothermal deposits. The PLS-DA results show that high Mo, As and V contents in scheelite are characteristic of magmatic-hydrothermal deposits formed under high oxygen fugacity such as oxidized skarns, whereas high Nb, Mn, Y and U contents are features of scheelite formed under reduced conditions, which are commonly associated with reduced skarns and quartz-veins/greisen Sn-W deposits. Scheelite from orogenic Au deposits displays predominantly positive Eu anomaly, high Sr and low Mo, Mn and Nb contents which differ from scheelite related to magmatic-hydrothermal deposits. Such differences allow discriminate scheelite associated with orogenic gold from those of magmatic-hydrothermal deposits. In addition to PLS-DA, two Random Forest models are proposed to assess the source of scheelite and the Au endowment of scheelite-bearing orogenic Au deposits. The high accuracy obtained by the two models enhances the use of trace element in scheelite not only as a robust and efficient tool for targeting scheelite-bearing deposits, but also to assess the fertility of scheelite-bearing orogenic Au deposits
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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