1,721,013 research outputs found
Phytochemical analysis, antioxidant and antimicrobial activity of wildand in vitro derived plants of Ceropegia thwaitesii Hook – An endemicspecies from Western Ghats, India
Ceropegia thwaitesii Hook (Asclepiadaceae), an endemic plant species, due to habitat destruction and overexploitation has a very restricted distribution in the Western Ghats of Tamil Nadu, India. The presentwrok aimed to determine the chemical composition, the total phenolic (TPC), flavonoid (TFC) and tannincontent (TEC), and to assess the antioxidant properties of various extracts of in vivo plants (IVP) andin vitro regenerated plants (IRP) of C. thwaitesii. Some phenolic compounds like gallic acid, cathechol,vanillin and salicylic acid were identified and quantified by HPLC. All the extracts possessed relevant rad-ical scavenging activity on DPPH, Superoxide radical scavenging activity, and Nitric oxide radicals as wellas total antioxidant ability. DPPH assay of in vitro methanol stems extracts and ethanol leaves extractsrevealed the best antioxidant properties with important IC50values of 0.248 ± 0.45 mg/mL and 0.397 ±0.67 mg/mL, respectively, whereas in vivo chloroform stems extracts showed a lower antioxidant activity(IC50of 10.99 ± 0.24 mg/mL). The IRP methanol extracts of stem and leaves had good inhibitory activityagainst all tested microorganisms in a dose-dependent manner. These results suggested that in vitroraised plants of C. thwaitesii are an excellent source of antioxidant compounds to be exploited on anindustrial level as food additive
Numerical investigation of two element camber morphing airfoil in low Reynolds number flows
Modern organisations and fayolism
Henri Fayol is widely considered to be the father of administrative management theory which
focussed on the development of broad administrative principles that were applicable to general
and higher managerial levels. Though his contribution to the field of management sciences is
indispensable, it is argued that some of the fourteen principles propounded by him are rather
outmoded due to the way the present-day organisations conduct their business
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
Dispelling the Myths Behind First-author Citation Counts
We 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
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