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    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

    Growth and tunneling spectroscopy of YBaCuO/PrBaCuO/HoBaCuO trilayers

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    We have measured SIS quasiparticle tunneling in YBaCuO/PrBaCuO/YBaCuO trilayers. The heterostructures were realized on SrTiO3 substrates, by sequential deposition of high quality (001) oriented epitaxial films, using a high pressure de sputtering in pure oxygen plasma. The YBaCuO films show a zero resistance and a diamagnetic transition temperature at 91 K, while the PrBaCuO barrier exhibits a semiconducting behavior. Conductance characteristics vs. voltage, at low biases, show well developed peaks indicative of gap structures at +/-45 mV, a flat background conductance for voltage greater than 50 mV and a ratio smaller than 0.1 between zero bias and normal state conductance

    Quasiparticle tunneling properties of planar YBa2Cu3O7-delta/PrBa2Cu3O7-delta/HoBa2CU3O7-delta heterostructures

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    We report a demonstration of S-I-S quasiparticle tunneling in c-axis oriented planar junctions consisting of YBaCuO/PrBaCuO/HoBaCuO thin film heterostructures. In the conductance curves at low temperatures well developed peaks indicative of gap structures are found at +/-45 mV. The high bias conductance shows flat dependence on energy and the best quality junction has a zero-bias conductance less than 0.05 of the normal state value. We discuss our spectra in the framework of a BCS-like density of states as well as in terms of a d(x)(2)-(2)(y) symmetry of the superconducting order parameter

    Growth and characterization of high-T-c based heterostructures

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    We have investigated several trilayers based on the Bi2Sr2CaCu2O8+delta and YBa2Cu3O7+delta families. Our trilayers were realized using Bi2Sr2YCu2O8+delta and PrBa2Cu3O7-delta oxide barriers respectively with thicknesses ranging between 100 Angstrom and 300 Angstrom. The films have been grown on (001) SrTiO3 substrates by means of dc sputtering deposition in high pressure oxygen plasma. Electrical resistivity measurements showed T-c = 87 K and 91 K for the Bi2Sr2CaCu2O8+delta and YBa2Cu3O7-delta electrodes, respectively, and a semiconductor-like behavior of the Bi2Sr2YCu2O8+delta and PrBa2Cu3O7-delta nonconducting layers. In the case of Bi2Sr2CaCu2O8+delta/Bi2Sr2YCu2O8+delta/Bi2Sr2CaCu2O8+delta junctions, the tunneling dynamical conductance, G(V), at low temperatures, indicated gap-like structures at +/-30 mV. For the YBa2Cu3O7-delta/PrBa2Cu3O7-delta/YBa2Cu3O7-delta junctions, the G(V) showed gap features with very well defined maxima at +/-45 mV and a very low conductance at zero bias. We discuss both these behaviors in close comparison with the results obtained in high-T-c based tunnel structures with natural barriers
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