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    The dependence of the weathering of soda–lime–silica glass on environmental parameters: a preliminary investigation

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    The chemical resistance (durability) of glass depends both on its chemical composition and on the chemical (type and amount of the molecules interacting with the glass surface) and physical (temperature, humidity, time, etc.) environmental parameters. A wide literature is available concerning glass weathering mechanisms, mainly involving leaching processes, but only few investigate the effects of each critical parameter. This study considers the dependence of soda–lime–silica glass alteration on temperature, relative humidity and time in the case of glass in a confined environment. The aim is to simulate the experimental conditions related to the weathering of the inner surface of empty glass containers that occurs during the storage in industrial pallets. A low cost experimental apparatus was set up, in which humidity and temperature were controlled by high performance homemade devices. The dependences of humidity, temperature and time on the glass leaching and on the formation of weathering products of low durability soda–lime–silica glass was investigated by optical and electronic microscopy (SEM), x-ray microanalysis and micro-infrared reflectance spectroscopy (IRRS)

    Studio preliminare sulla produzione e il degrado di vetri potassici e sodici come modelli di vetrate artistiche e di vetri industriali in ambiente confinato

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    This study concerns the alteration of glass in confined environment , characteristic of the industrial glass containers stored inpallets before filling and of the artistic stained-glass windows protected by a glazing system . In order to better understandin the different influence of the parameters of glass alteration (chemical durability, temperature, relative humidity and exposition time), an ex-novo low-expensive system ha sbeen designed and realized for the reproduction of a confined environment and for the measure and control of relative humidity and temperature. Soda-lime silica glass and potash-lime silica glass samples have been produced as models of glass containers and medieval artistic stained glass windows repectively. Outdoor and indoor (in stove) expositions of the glass samples have been performed and the weathering of the samples has been investigated by different analytical techniques, such as optical microscopy, SEM-EDS and Micro-IRRS

    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
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