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Isolamento di principi attivi da estratti di Crepis lacera e valutazione dell'attività proliferativa in cellule renali di bovino
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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Antiproliferative Oleanane Saponins from Dizygotheca elegantissima
No full textFour new oleanane saponins (1-4), together with three known saponins, were isolated from the aerial parts of Dizygotheca elegantissima R. Vig. & Guillaumin.
Their structures were elucidated by 1D and 2D NMR experiments including 1D TOCSY, DQF-COSY, HSQC, and HMBC spectroscopy, as well as ESIMS
analysis. The antiproliferative activity of all isolated compounds was evaluated
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe 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
Sesquiterpenes and monoterpenes from Ammoides atlantica (Coss. Et Dur.) Wolf.
No full textThe genus Ammoides (Apiaceae) tribe of Ammineae includes two species in Algeria, one of which is endemic: Ammoides
atlantica (Coss. et Dur.) Wolf; the other one, Ammoides pusilla (Brot.) Breistr, is widespread in the Mediterranean region.
These species are used in folk medicine as antibacterial, anti-diarrhoea, anti-fever, antiinfluenza and to treat vitiligo in
addition of their use as condiments (Bellakhdar J, 1997).
Ammoides atlantica is biennal or perennial plant with thick stem fitted with a rosette of basal leaves. Slightly branched
stems. Leaves Umbels 3-6 rays. Fruit 2-2.5 mm, it is found in lawns mountains above 1000 m (Quezel and Santa., 1962).
In Algerian traditional medicine, the arial parts of Ammoides atlantica are reported to have a wide range of biological
activities such as antibacterial, antioxidant, anthidiarrheic and diabetic activies (Ababsa et al., 2013; Laouer et al., 2003).
Ammoides atlantica arial parts were subjected to extraction with solvents polarity increased, n-hexane, CHCl3, CHCl3-
MeOH (9:1) and MeOH. The study of the extracts was carried out using different chromatographic techniques such as
Silica gel, SephadexLH-20, MPLC, and rp-HPLC. Part of chloroform extract (4.5 g) was subjected to column
chromatography using silica gel and eluting with CHCl3 followed by increasing concentrations of MeOH in CHCl3 (between
1% and 100%). Fractions of 50 ml were collected and analyzed by TLC.
Preliminary study of CHCl3 extract led to isolation of some pure compounds whose structures were elucidated by 1D-and
2D-NMR Spectroscopy (1H, 13C, 13C DEPT, DQF-COSY, HSQC, HMBC, ROESY) and confirmed by mass spectrometry.
Seven compounds from CHCl3 extract were isolated: one monoterpene chrysanthenone, two glicosides monoterpenes as
l-borneol O-β-D-glucopyranoside (Asano et al., 1993) and (-)-cis-chrysanthenol-β-D-glucopyranoside (Miyakado et al., 1974),
three guaianolides as 9α-Acetoxyartecanin, 3α-Chloro-9α-acetoxy-4β,10α-dihydroxy-1β,2β-epoxy-5α,7αH-guai-11(13)-en12,6α-olide and apressin (Trifunovic ́ et al., 2006) and a new bisabolene sesquiterpene derivative 1,4-dihydroxybisabol-2,11-
diene-10-one
In vitro vivida activity of hypoestes forskaolii (VAHL) Roem. & Schult. (Acanthaceae) on sheep gastrointestinal nematodes: preliminary results
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