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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
NMR and computational study on the anomeric effect in cis/trans-3,4-dihydro-2-alkoxy-4-substituted-2H,5H-pyrano[3,2-c][1]benzo pyran-5-one derivatives
No full textThe configuration and conformation of cis/trans-3,4-dihydro-2-alkoxy-4-(alkyl-or aryl-substituted)-2H,5H-pyrano[3,2-c][1]benzopyran-5-one derivatives were studied by combined NMR and computational analyses. The cis/trans configurational assignments of all diastereoisomers were achieved via 2D NOESY experiments, The conformational analysis of eis compounds, performed via NMR and computational studies, allowed the establishment of a preference for the conformer with both substituents in the pseudo-equatorial orientations. For trans derivatives only the molecular mechanics analysis produced meaningful results, suggesting a general prevalence for the conformer bearing the 2-alkoxy group in a pseudo-axial and the 4-substituent in a pseudo-equatorial orientation. (C) 1997 John Wiley & Sons, Ltd
4-HYDROXYCOUMARIN AND RELATED SYSTEMS: SITOSELECTIVITY OF THE MITSUNOBU REACTION WITH PRENYL ALCOHOLS
No full textA mild hydrogenolytic-hydrolytic conversion of oximes to carbonyl compounds
No full textOximes are converted into the corresponding carbonyl compounds in high yields using Raney-nickel and sodium hypophosphite at pH 5
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
The absolute sterochemistry of 2 furanogermacranes of myrrh as determined by the circular-dichroism exciton chirality method
No full textAppropriate 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
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