1,721,151 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Farkas e János Bolyai: dalla teoria delle parallele alla quadratura del cerchio
No full textL'articolo propone una analisi storica della figura e dell'opera di János Bolyai nella quale si affronta con particolare attenzione il tema dei suoi rapporti scientifici col padre Farkas e con Gauss. Sono analizzate alcune sezioni dell'Appendix, segnatamente le sezioni conclusive dell'opera che sono dedicate al problema della quadratura del cerchio. Alla luce di tale analisi viene offerta un riconsiderazione critica di alcune tesi storiografiche ampiamente diffuse e una rivalutazione del contributo di Gauss al processo di scoperta delle geometrie non-euclidee
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Coordination modes of hydroxamic acids in copper(II), nickel(II) and zinc(II) mixed-ligand complexes in aqueous solution
No full textThe stability constants and coordination modes of the mixed-ligand complexes formed by Cu(II), Ni(II), Zn(II), ethylenediamine ten), 2,2'-bipyridine (bpy), glycinate (Gly), disodium salt of 4,5-dihydroxybenzene 1,3-disulfonate (Tiron), diethylenetriamine (dien) or 2,2':6,2 "-terpyridine (terpy)( = ligand B) and acetohydroxamate (Aha), N-methylacetohydroxamate (MeAha) or N-phenylacetohydroxamate (PhAha) ( = ligand A) were determined in water (25 degrees C, I = 0.2 M KCl) by pH-metric, spectrophotometric, EPR and calorimetric methods. Mixed-ligand complexes with typical hydroxamate type chelation mode involving the NHO- moiety are formed in all systems. However, further copper(II) induced deprotonation of the NHO- moiety of Aha in the presence of en or bpy results in the formation of mixed-ligand complexes with hydroximato chelates at high pH. The results show the favoured coordination of a hydroxamate to metal(II)-en and especially to a metal(II)-bpy moiety. If ligand B is Gly, the increase of stability of the mixed-ligand complexes is as expected on statistical basis, whereas the formation of complexes involving O,O-coordinated hydroxamate and O,O-coordinated Tiron is unfavoured. The tridentate coordination of dien or terpy results in five-coordinated mixed-ligand copper(II) complexes in which, most probably, the hydroxamate moiety adopts an equatorial-axial coordination mode. This quite unstable hydroxamate chelate can not hinder the hydrolysis of the complex above pH 8. Under very basic conditions acetohydroximato moieties (-CONO2-) displace the rigid terpy ligand from the coordination sphere and complexes, [Cu(AhaH(-1))(2)](2-) involving hydroximato chelates are formed. (C) 2000 Elsevier Science Ltd. All rights reserved
Copper(II), nickel(II), zinc(II), and molybdenum(VI) complexes of desferrioxamine B in aqueous solution
No full textBased on pH-metric, spectrophotometric, and EPR measurements, stability constants and bonding modes are reported for the complexes formed in aqueous solutions of the copper(II)-, nickel(II)-, zinc(II)-, and molybdenum(VI)-desferrioxamine B (DFA) systems. Besides the totally deprotonated species, several protonated mononuclear complexes were found in the copper(II)-, nickel(II)-, and zinc(II)-DFA systems, and also the dinuclear species [Cu(2)AH](2+). All three hydroxamate groups are able to coordinate to nickel(II) and zinc(II), but only two of them to the copper(II). Molybdenum(VI) yields only one complex species, [MoO2(H(2)DFA)](+). This species, which exists below pH 7, involves two hydroxamate groups coordinated to the metal ion. DFA completely prevents the formation of polyoxomolybdates below pH 7, but MoO42- and free DFA exist above this pH. (C) 1997 Elsevier Science Inc
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