1,721,020 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

    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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    Latest updates in ElectroPhotoChemical reactions

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    In the last twenty years, electrochemistry and photochemistry have attracted a renewed and still uprising interest in organic synthesis. Two of the most simple and abundant reagents, electrons and photons, became the key players in synthetic chemistry as cornerstones of developing greener and sustainable chemical processes. An interesting strategy that recently emerged is the possibility of merging the two worlds in what is called ElectroPhotoChemistry (EPC). In particular, this review will focus on the most recent contributions in the field. The basic principles of EPC will be presented along with a discussion of the published works of the last few years. Electrophotochemical oxidation/reduction reactions will be discussed, including in this section the transformations of a C–H bond to a C-X (X: heteroatom). In the C–H activation chapter the formation of C–C bond, starting from a C–H bond, will be considered. Finally, the miscellaneous chapter includes examples which do not clearly belong to the previous categories

    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

    Crystal chemistry of trioctahedral micas-1M from the Alto Paranaiba Igneous Province, Southeastern Brazil

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    The crystal structures of nine trioctahedral mica-1M crystals (phlogopite and ferroan phlogopite containing Fe3+ in tetrahedral position, ferroan tetra-ferriphlogopite, and titanian phlogopite), from ultramafic alkaline-silicate lavas and alkaline-silicate, silicate-carbonatite and carbonatite plutonic rocks occurring in the Alto Paranaiba Igneous Province (southeastern Brazil), were refined from single-crystal X-ray data in the space group C2/m to R values between 0.025 and 0.039. These mica crystals are characterized by low to very low At content; therefore, Fell may be essential to fill the tetrahedral site. The octahedral position of all the crystals studied is characterized by variable amounts of Fe2+, Fe3+ and Ti4+ in substitution for Mg. The two independent octahedral sites. M1 and M2, show equivalent mean electron-density and mean bond-distances in most cases. Order at the octahedral sites is enhanced in the Ti-rich crystal from Presidente Olegario owing to the preference of Ti for the M2 site. The lateral parameters a and b reflect variations in tetrahedron composition, whereas the periodicity along c depends on octahedron composition. The crystal-chemical features of these micas are controlled by the peculiar composition of the rocks, by the high f(O-2), a(H2O), and f(CO2), and by metasomatic events that have affected the Alto Paranaiba Igneous Province

    A convenient protocol for a zinc-catalysed synthesis of electron-poor indoles

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    A convenient catalytic protocol for the synthesis of electron-poor indoles was envisioned. A cyclisation reaction of electron-deficient 2-(alkynyl)-anilines, catalysed by Zn(II) salts, was successfully developed and applied to the synthesis of an API precursor. A two-step one-pot procedure starting from aniline derivatives was successfully developed. The use of a readily available, non-noble metal further enhanced the value of the protocol
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