1,720,961 research outputs found
Cytotoxic constituents from Anagyris foetida leaves
No full textAnagyris foetida extracts were investigated in preliminary cytotoxic tests against two tumour cell lines. Chromatographic
separations on active extracts led to the isolation of two alkaloids, anagyrine (1) and baptifoline (2), as well of isorhamnetin (3) and
syringin 4-O-β-D-glucopyranoside (4). In vitro cytotoxicity of compounds 1–3 was also evaluated
Evaluation of in vitro antioxidant properties of some traditional Sardinian medicinal plants: Investigation of the high antioxidant capacity of Rubus ulmifolius
No full textThe antioxidant capacities of 11 botanical species used in the tradition of Sardinia as teas beverages or as decoction for medicinal
purposes were evaluated using different in vitro methods (BR, TEAC, DPPH and FC). Among the various species, Rubus ulmifolius,
resulted the more active with all the used methods. Phytochemical investigation on the extract yields in the isolation of several phenolic
compounds namely caffeic acid, ferulic acid, quercetin-3-O-glucuronide, kaempferol-3-O-glucuronide, kaempferol-3-O-(600-p-coumaroyl)-
b-D-glucopyranoside, kaempferol-3-O-(600-caffeoyl)-b-D-glucopyranoside, chlorogenic acid, 4-caffeoylquinic acid and 5-caffeoylquinic
acid. The antioxidant activity of isolated compounds was also evaluated
Image analysis application on waterlogged archaeological Prunus remains from a medieval context in Sardinia
Full text linkTwo new sesquiterpene lactones from the leaves of Laurus nobilis
No full textAs a part of our ongoing interest in new bioactive compounds from natural sources, we studied Laurus nobilis
(Lauraceae). This plant is widespread in the Mediterranean area and is used for medicinal and economic
purposes. Chromatographic separations on active extracts led to the isolation of two new sesquiterpene lactones,
5a,9-dimethyl-3-methylene-3,3a,4,5,5a,6,7,8-octahydro-1-oxacyclopenta[c]azulen-2-one (1) and 3b -chlorodehydrocostuslactone
(2). The structures of the new compounds were identified by 1D and 2D NMR experiments, as
well as high resolution mass spectrometry. The cytotoxic activity was also evaluated against three different tumor
cell lines of human origin
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
Extremes Rainfall Events on Riparian Flora and Vegetation in the Mediterranean Basin: A Challenging but Completely Unexplored Theme
Full text linkIn a global climate change scenario “Extreme climatic events” are expected to widely affect flora and vegetation in Med-regions, especially “Extremes Rainfall Events” which will have impacts on riparian environments. Aiming to provide an in-depth picture on the effects of these events on the riparian flora and vegetation in the Mediterranean Basin, especially focusing on islands, a bibliographic search was performed in the main international databases, which led to 571 articles published from 2000 to 2021. Most studies have analyzed these phenomena from the climatic point of view identifying three main topics “Rainfall”, “Global/Climate change”, and “Flood”. 81 papers concerned effects of extreme events on Mediterranean woodland formations and cultivated plants. A further analysis focused on European countries and Mediterranean bioregion using “Extreme rainfall events” and “Extreme rainfall and floods” as keywords. A low number of records relating to Mediterranean island regions was found, having Sicily as the study area. Moreover, seven articles had Sardinia as a study area, four of which referred to flora and vegetation. A lack of studies on the effects of extreme rainfall events on riparian flora and vegetation were highlighted. This review constitutes a call for researchers to explore extreme phenomena that have become recurrent in the Mediterranean Basin
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