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The Railway Library And Other Literary Rubbish That Travels By The Rail
No full textAround the mid-nineteenth century, a new sort of book appeared on the shelves: books produced for a mass market mainly using mechanical printing processes such as steam-operated printing machines, industrially produced paper, stereotyped and electrotyped printing matrices, and so forth
Interplay between Cyclization and Polymerization in Ditopic Cavitand Monomers
No full textQuinoxaline kite velcrands were functionalized with a ureidopyrimidone moiety at the lower rim, in order to combine multiple hydrogen bonding and solvophobic interactions to build dual-coded supramolecular structures. The orthogonality of the selected binding motifs has been demonstrated by NMR studies, as well as the reversible nature of the obtained assemblies. At low concentration, the presence of a ring-chain equilibrium has been established by 1H NMR experiments, and confirmed by static and dynamic light scattering measurement
Ion-Pair Complexation with a Cavitand Receptor
No full textThe capability of resorcinarenes to bind anions within the alkyl feet at the lower rim has been exploited as the starting point for developing a new cavitand able to engulf contact ion pairs of primary ammonium salts in chlorinated solvents with association constants (Kass) in the range of 103104M-1. Methylene bridges were introduced into the upper rim to freeze the resorcinarene in the cone conformation with the four Hdown protons converging in the lower pocket, thereby maximizing the CH-anion interactions responsible for the anion binding. Four additional phosphate moieties were introduced into the lower rim in close prox-imity to the anionic site to provide hydrogen-bonding-acceptor P=O groups and promote cation complexation at the bottom of the cavitand. The binding ability of the synthesized ligands was analyzed by 1H NMR spectroscopy and, when possible, by isothermal titration calorimetry (ITC); the data were in agreement when complementary techniques were used
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
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
Host-Guest Driven Self-Assembly of Linear and Star Supramolecular Polymers
No full textSupramolecular plasticity: The remarkable host–guest properties of phosphonate cavitands have been exploited in the self-assembly of supramolecular polymers (see picture) that feature guest triggered reversibility and template-driven conversion from linear into star-branched forms. The structurally similar but complexation-inefficient thiophosphonate cavitand acts as chain stopper to control the degree of polymerization
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