1,720,966 research outputs found

    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

    Chitosan from mushroom by-products: sustainable extraction process and winemaking application

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    Chitosan is a biopolymer industrially obtained from the deacetylation of chitin, the second most abundant polysaccharide on earth, after cellulose. It is extracted from various terrestrial and marine resources, including insects, grasshoppers, shrimps, crabs, lobsters, squids, and fungi. Chitosan has a polycationic character due to the free amine groups along its chemical backbone, and depending on its deacetylation degree (dd) and molecular weight (mw), it shows variable properties that differ from those of other natural polysaccharides. It is an outstanding polymer with low toxicity, high biodegradability, chelating, anticoagulant, antioxidant, and antimicrobial activities. Fungal chitosan from aspergillus niger is the only type accepted in winemaking to avoid any potential concerns about allergenicity because of the crustacean raw material. The addition to wines is currently aimed at controlling unwanted microbial growth, particularly brettanomyces spp., preventing iron and copper casses, and removing heavy metals and ochratoxin a. The addition of fungal chitosan in musts and wines has also been successfully authorized for fining and clarification purposes to reduce turbidity by precipitating suspended particles or proteinaceous matter. The recommended doses of chitosan range from 10 g/hl to 500 g/hl for microbial control, iron and copper haze prevention, and heavy metal and contaminant reduction. This limit is set at 100 g/hl only for fining purposes. The conventional production of chitin and chitosan involves deproteinization, demineralization, decolorization, and deacetylation steps. Acid, alkaline, or enzymatic processes are commonly performed. However, these methods are long-time consuming, low-efficient, and require large volumes of solvents and hazardous chemicals. Several greener strategies and technologies have been proposed. Subcritical water technology is one of the most promising and versatile processes. Subcritical water extraction (swe) is usually conducted at temperatures ranging from 100 to 374°c, under sufficient pressure to keep water in a liquid state. Swe offers several advantages, including fast reaction rates, the replacement of acids/bases with a more environmentally sustainable solvent, and its properties can be finely modulated. Moreover, the identification of new undervalued and unexploited biomasses, such as edible mushroom by-products, should also be promoted for eco-friendlier chitosan production. In the present work, a sustainable extraction process with subcritical water from mushroom (pleourotus ostreatus) by-products was performed. Swe allowed a 4.5-fold increase in extraction yield and a 4-fold reduction in process time. The chitin and chitosan were characterized and compared with conventional ones. Significant effects were pointed out on some chemical properties, such as deacetylation degree, crystallinity index, and chromatic properties, according to the adopted subcritical conditions. The swe chitosan was also studied for winemaking purposes. Several experimental trials were performed at different dosages (0-100 g/hl), on several unstable white wines, aimed to point out significant interactions with proteins, polyphenols, and aroma compounds. Positive effects were highlighted on some analytical indices related to wine protein stability, and a significant decrease in unstable proteins was detected, for both chitinases and thaumatin-like proteins (tlps). The swe chitosan didn’t affect the chromatic characteristics of wines or the total polyphenol content. Moreover, the chromatographic analysis of volatile compounds showed no significant effects on the main chemical classes. Further research is already undergone, aimed at deeply investigating the effect of subcritical water at different conditions on the chitosan polymeric structure and its functionality for winemaking applications

    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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