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Chemical composition of the essential oil from Jasminum pubescens (Retz.) Willd. (Oleaceae) leaves and flowers
No full textThe essential oil obtained from the leaves and flowers of Jasminum pubescens (Retz.) Willd. (Oleaceae) has been analyzed by GC/MS. Sixty-three and sixty-four components of the essential oils, representing 95.0% of the total oil for the leaves and 91.9% for the flowers, were identified, resp. Both the oils were mainly constituted by non-terpene derivs. (58.2% and 50.8%, resp.), among which aldehydes (44.7%) characterized the essential oil from the leaves. Besides aldehydes (14.3%) and other carbonylic compds. (acids, esters, and ketones, 38.1%) were the main non-terpene compds. of the oil from the flowers
Isolamento e caratterizzazione strutturale di diterpeni da Podocarpus elongatus (Aiton) L’Her. Ex Pers. E Podarcapus gracilior Pilger (Podocarpaceae) e identificazione della loro attività biologica
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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
Steroidal saponins from the aerial parts of Tribulus alatus Del
No full textSix steroidal glycosides (1-6) were isolated from the aerial parts of Tribulus alatus Del. (Zygophyllaceae), together with one known cholestane, one spirostane, and six flavonol glycosides. Among them, 1 and 2 possess a furostane-type aglycon, 3 and 6 a cholestane structure, and 4 and 5 a spirostane skeleton. Their structural elucidation was accomplished by extensive spectroscopic methods including 1D (1H, 13C, 13C DEPT, TOCSY, ROESY) and 2D NMR expts. (DQF-COSY, HSQC, HMBC) as well as ESI-MS anal
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
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