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A CRITICISM OF THE HOLM-MUNKSGAARD OXYGEN AND STRONTIUM ISOTOPE STUDY OF THE VULSINIAN DISTRICT (CENTRAL ITALY)
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Comparisons of ^(18)O/^(16)O and ^(87)Sr/^(86)Sr in volcanic rocks from the Pontine Islands, M. Ernici, and Campania with other areas in Italy
No full textNew ^(18)O/^(16)O and ^(87)Sr/^(86)Sr data dramatically confirm and extend the systematic regional isotopic and geographic correlations observed in Quaternary volcanic rocks from Italy: (1) The High K Series (HKS) and Low-K Series (LKS) potassic magma source regions are isotopically distinct; the relatively rare, primitive (high-Ca) parent magmas of both suites have δ^(18)O = +5.5 to +7.5, but the
LKS parent has a much lower ^(85)Sr/^(86)Sr and slightly lower δ^(18)O than the HKS parent. (2) The more abundant evolved (fractionated) magmas of both suites have a wide range of δ^(18)O (+6.0 to + 13.0), but in the offshore island centers (Ischia, Pontine Is., Procida) these magmas are all much lower in δ^(18)O ( < +8.0) than those from the Italian mainland, as a result of the absence of involvement of high-^(18)O continental crust. (3) At a given center, the ^(18)O-enrichments correlate with major-element
changes (i.e., CaO depletion and K_2O and SiO_2 enrichment) attributable to fractional crystallization in crustal magma chambers ( 4 to 13 km depth?); because such ^(18)O enrichments cannot be produced in a closed system, these correlations imply that AFC processes were important, particularly north of Rome where they are enhanced by an increase in the temperature of the crust (due to igneous
activity associated with the 0-7 Ma Tuscan anatectic event). Thus, the high δ^(18)O values of the potassic
magmas of Italy should not be used as evidence in support of genetic models invoking recent subduction of sedimentary rocks into the source regions of these magmas. (4) On δ^(18)O vs. ^(87)Sr/^(86)Sr diagrams, the LKS and HKS magmas at each volcanic center display separate, steep positive trends indicating mixing with high-^(18)O continental crustal material; this type of mixing had little effect on ^(87)Sr/^(86)Sr in these Sr-rich magmas, but it had a dramatic effect on the δ^(18)O values. (5) Two distinctly different groups of rhyolites and quartz-normative trachytes are observed in the northernmost Pontine Islands, a high-^(18)O group similar to the anatectic Tuscan rhyolites (δ^(18)O > + 10) and a low-^(18)O group similar to the rhyolites of the Aeolian Islands (δ^(18)O = +7 to +7.5). (6) All of the magmas produced in and around Italy during the past five million years can be derived by mixing of(i) a SiO_2-rich continental crustal end member, having ^(87)Sr/^(86)Sr ~ 0. 715 to 0. 735 and δ^(18)O ~ + 10 to + 20, with three distinct mantle end members: (ii) a relatively low-K (LKS), moderate-Sr parent with ^(87)Sr/^(86)Sr ~ 0.706 and
δ^(18)O ~ +6, dominant to the south of Rome and perhaps related to an upper mantle source modified by a recent subduction event; (iii) a high-K (HKS), high-Sr parent with ^(87)Sr/^(86)Sr ~ 0.711 and δ^(18)O ~ + 7 dominant in the vicinity of Rome and farther north, and possibly related to older subcontinental mantle modified by a recent metasomatic event; and (iv) a very low-K, low-Sr Tyrrhenian Sea MORB type parent with ^(87)Sr/^(86)Sr~ 0.7025 and δ^(18)O ~ +5.7
Variations on the Author
Full text link“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
Full text linkWe 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
Full text linkWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe 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-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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