1,721,047 research outputs found
Iridoid and bisiridoid glycosides from Globularia meridionalis (Podp.) O. Schwarz aerial and underground parts
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
“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
We 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
Radical scavenging activity and cholinesterase inhibitory activity of Leopoldia comosa (L.) bulbs
Antioxidant and Antibacterial Activities on Foodborne Pathogens of Artocarpus heterophyllus Lam. (Moraceae) Leaves Extracts
Antioxidant and anti-cholinesterase activity of Globularia meridionalis extracts and isolated constituents
The antioxidant and anti-cholinesterase properties of Globularia meridionalis (Podp.) O. Schwarz (Globulariaceae) were investigated. G. meridionalis aerial parts and roots were extracted with methanol, and the total extract successively partitioned with n-hexane. The methanol fraction of the roots showed the highest antioxidant activity with IC 50 values of 8.0 and 2.1 μg/mL in the DPPH and β-carotene bleaching tests, respectively. From this fraction, three flavonoids, namely pectolinarigenin 7-O-β-glucoside, apigenin 7-O-β-glucoside and luteolin, and two phenylethanoids, namely acteoside and isoacteoside, were isolated. Potential anti-cholinesterase effects were assessed through the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes inhibition assay. The n-hexane fraction of the roots exhibited the highest activity against both AChE and BChE with IC 50 values of 65.5 and 70.4 μg/mL, respectively
Radical scavenging, antioxidant and metal chelating activities of Annona cherimola Mill. (cherimoya) peel and pulp in relation to their total phenolic and total flavonoid contents
This study aimed to evaluate the total phenolic and flavonoid content, radical scavenging activity (by DPPH and ABTS tests) and antioxidant capacity (by β-carotene bleaching test) of Annona cherimola (cherimoya) fruits cultivated in Italy for human consumption. The metal chelating activity and ferric reducing power were also determined. A. cherimola peel and pulp were characterized by a total phenolic content of 14.6 and 12.6mg chlorogenic acid equivalents/100g fresh weight, respectively. A similar trend was observed with flavonoid content. Both extracts exhibited high antioxidant activity through different mechanisms of action. In particular, peel extract demonstrated the strongest free radical scavenging activity with an IC 50 value of 57.7μg/mL. The same extract was more effective in preventing β-carotene oxidation (IC 50 value of 63.5μg/mL after 60min) and showed higher chelating ability (IC 50 value of 79.6μg/mL) than pulp extract. This work demonstrated the high quality of cherimoya fruits cultivated in Italy, and recommends the peel of this fruit product that may be of interest from a functional point of view as a major source of natural antioxidants. © 2011 Elsevier Inc
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