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ESSENTIAL OIL COMPOSITION OF SOME CENTAUREA SP. (ASTERACEAE) FROM DIFFERENT ITALIAN ISLANDS
No full textThe volatile constituents of leaves and flower heads of several Centaurea spcies from different islands of Ligurian and Tyrrhenian Sea were investigated for the first time. C. veneris (Sommier) Bég. from Palmaria Island (Ligurian Sea),C. gymnocarpa Moris & De Not. from Capraia Island, C. aetaliae (Somm.) Bég. and C. ilvensis (Sommier) Arrigoni from Elba Island (Northern Tyrrhenian Sea); C. aeolica Lojac. subsp. aeolica from Lipari, Aeolian Islands, C. busambarensis Guss., C. panormitana Lojac. subsp. ucriae (Lacaita) Greuter, C. panormitana Lojac. subsp. umbrosa (Fiori) Greuter, C. panormitana Lojac. subsp. todaroi (Lacaita) Greuter, C. panormitana Lojac. subsp. seguenzae (Lacaita) Greuter from different localities in Sicilia (southern Tyrrhenian Sea), were collected at flowering stage. All samples were extracted by steam distillation to obtain the volatile fraction with a yield ranging from 0.02-0.13% in leaves and 0.01-0.09% in flower heads (weight/fresh weight basis), respectively. The oils were then analyzed by GC/FID and GC/MS methods and more than 100 compounds belonging to several chemical classes were identified and quantified in all the samples. Sesquiterpenes represent the most abundant class of compounds (22.35-61.67% and 35.16-57.51% of the total volatiles in leaves and flower heads, respectively) of which germacrene D was the dominant constituent (10.03-42.65% and 7.33-30.32% in leaves and flower heads, respectively). Aldehydes, hydrocarbons, ketones, monoterpenes, alcohols, acids, esters and miscellaneous compounds were also identified and quantified in different amount in the volatile oils from all the examined plant organs. Other compounds were also detected and they appear to be species-specific, as their presence was only detected in either one or the other Centaurea species
Plants and their extracts to improve animal wellbeing: from a traditional use to new feed additives for livestock production
No full textSolution structure of a Bowman Birk Inhibitor isolated from snail medic seeds (Medicago Scutellata) showing anticarcinogenic activity and analysis of self-association behaviour
No full textVolatile components of two endemic species from the Apuan Alps (Tuscany, Italy) Centaurea aachnoidea and C. montis-borlae. (Asteraceae)
No full textThe volatile fractions of Centaurea arachnoidea and C. montis-borlae, two endemic species growing wild on the Apuan Alps (Tuscany, Italy), were isolated by steam distillation from fresh leaves and flowerheads and analyzed by GC/FID and GC/MS. The yield in essential oil ranged from 0.01% to 0.09% of fresh material. A wide variety of volatile compounds was detected in the examined plant species and organs, both in qualitative and quantitative terms. Sesquiterpenes were identified as the major constituents ranging from 18.9% to 73.2% of the total oil. Alcohols (1.6-25.8%), aldehydes (1.5-12.0%), hydrocarbons (1.8-11.9%), acids (0.2-25.4%), esters (0.2-1.3%), monoterpenes (0.7-1.4%), and miscellaneous compounds (0.6-2.6%), were also detected at variable amounts in all different sample tissues. A series of unidentified compounds was also isolated from the two species, both in leaves and flowerheads, accounting for 2.4-6.7% of the total oil. According to MS spectral data, these substances likely belong to the class of polyunsaturated compounds; moreover they appear to be species-specific, as their presence was only detected either in one or in the other Centaurea species
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
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
From vegetable food waste to earthworms as novel food/feed: nutritional characteristics
No full textFrom vegetable food waste to earthworms as novel food/feed: nutritional characteristics D. Tedesco1, A. Tava2 and J.Parisi1 1Department of Health, Animal Science and Food Safety, University of Milan, Via Celoria 10, 20133, Milano,Italy, 2Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria, viale Piacenza 29, 26900 Lodi, Earthworms grown on fruit and vegetable waste can be a future alternative and sustainable food/feed source, contributing to waste disposal efficiency, responding to global food demand and reducing greenhouse gases (GHG) emission. As a part of studies on the feasibility to transform vegetable food wastes in this novel protein source, we evaluated the nutritional characteristic of earthworms (Eisenia foetida) reared on food vegetable waste from different rearing cycle. The focus was to evaluate the protein and fat content and the amino acids and fatty acids profile. Briefly, approximately 800 earthworms were separated from each substrate, washed in running controlled water to remove dirt from the body surface, kept in saline solution at room temperature changing the solution until the digestive system was clean, and then freeze – dried for further analyses. Samples of earthworms were analyzed for crude protein (CP) and total amino acids content, determined by the High Performance Liquid Chromatography (HPLC) analysis. Amino acids were quanti.ed according to calibration curves made with pure reference compounds, using the internal standard method. The ether extract was evaluated by solvent extraction, fatty acids profile was determined using reference fatty acid methyl esters (FAME) by gaschromatography flame ionization detector (GC/FID) analysis. The CP content ranged from 64.4% to 67.15% of the dry matter. The earthworm samples contain all the essential amino acids, with high lysine, threonine and arginine level. Total fats were quantified from 9.3% to 10.84% dry weight, while the fatty acids composition revealed a great amount of polyunsaturated fatty acids (PUFA), quantified from 40.32% to 43.91% of the total. Among PUFA, the .3 and .6 series were steadily well represented, ranged from 7.5% to 8.22% of the total amount. From these results, earthworms reared on vegetable food waste, showed an attractive nutritional profile for food/feed applications
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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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