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    Geology, alteration and precious metal reconnaissance of the Nogal Canyon area, San Mateo Mts., N.M.

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    1984 Summer.Includes bibliographical references.The Nogal Canyon area lies within the southern San Mateo mountains and displays epithermal, volcanic hosted precious metal occurrences in the San Jose and Quartz Hill districts and in the Aragon Hill area. The San Mateos represent an isolated, north trending, eastward tilted, structural block located in the northeastern portion of the Cenozoic Mogollon-Datil volcanic field. Mid-Tertiary, calc-alkalic andesites to high silica rhyolites and minor volcaniclastics dominate the lithologies exposed in the Nogal Canyon area. The Oligocene Spears Formation, the oldest unit present, consists of andesitic to latitic flows, breccias, and ash-flow tuff and sporadic volcaniclastic sandstone. The Hells Mesa rhyolite ash-flow tuff overlies the Spears Formation and is sequentially superimposed by the Unit of Luna Park which includes andesitic flows, dacite flow breccias, rhyolite tuff, and minor volcaniclastics. The majority of the upper felsic sequence exposed in the southern San Mateos consists of the Oligocene Vicks Peak Tuff, a thick, densely to partially welded rhyolite ash-flow tuff, and the overlying Springtime Canyon Quartz Latite. Younger porphyritic rhyolite intrusives, rhyolite flow-dome rocks, and intrusive breccia appear localized along major structural trends within the southern foothills of the San Mateo mountains. Major northeast and northwest trending, steeply dipping, normal faults crosscut the Vicks Peak Tuff and host "fissure type" precious metal occurrences in the San Jose district. Structural preparation relates either to the proposed Nogal Canyon cauldron or to mid-late Tertiary regional extensional tectonism. Hydrothermal alteration effects contemporaneous with precious metal mineralization consist of pervasive and veinlet silicification, pervasive intermediate arqillic alteration, and quartz-alunite replacement alteration. Silica alteration is strongly localized along fracture and breccia zones consisting of vein-infillings, pervasive wall rock alteration, and quartz network-stockwork type occurrences. The gangue mineral assemblage accompanying vein-infilling silicification includes adularia, sericite, calcite, pyrolusite, and cryptomelane. Intermediate argillic alteration consists of montmorillonite, montmorillonite-illite mixed layer, illite, kaolinite, and pyrite systematically zoned as reaction aureoles about major structures. Argillic alteration broadens beneath the Vicks Peak Tuff-Springtime Canyon Quartz Latite contact which acted as a permeability barrier to ascending hydrothermal solutions. Quartz-alunite alteration occurs as a really restricted, pervasive replacement deposits with accessory pyrite, specularite, kaolinite, and chalcedony. Mineralization accompanying vein-related silicification consists of native silver, native gold, cerargyrite, and pyrite and appears modified by supergene oxidation processes. Trace element studies indicate the mineralization exhibits low arsenic and antimony signatures and lacks base metal introduction at present erosional levels. A single hydrothermal episode which generated structurally confined boiling appears responsible for the development of hypogene alteration and insignificant silver-gold mineralization centered over the Nogal Canyon area. Precious metal occurrences at Aragon Hill consist of gold bearing, quartz-calcite-barite fracture fillings crosscutting the Aragon Hill intrusive breccia. Pervasive phyllic alteration, contemporaneous with breccia emplacement, occurs throughout the pipe-like intrusive breccia and concentrically envelopes the surrounding rhyolite flow-dome rocks. Phyllic alteration consists of sericite, montmorillonite-chlorite mixed layer clay, quartz, pyrite, and kaolinite products. The precious metal bearing fracture fillings probably represent leaching and minor metal deposition during the late waning stages of breccia emplacement, or possibly high level expression of epigenetic breccia-hosted silver-gold mineralization at depth

    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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