1,720,999 research outputs found
Overview of analytical methods for beavericin and fusaproliferin in food matrices
No full textIn the recent years, food safety has known an increasingly interest from both the consumers and the scientific community, and this resulted in a major focus among the objectives of the international institutions responsible for the food safety monitoring e.g. the European Union or the EFSA. One of the aspects that are of greater attention is the food colonization by microscopic fungi in aerobic conditions producing toxic secondary metabolites known as mycotoxins and their accumulation in the food chain. While numerous studies in the literature on surveillance, detoxification, prevention, and toxicological aspects are mostly concentrated on major mycotoxins such as aflatoxins, ochratoxin A, trichothecenes and fumonisins, secondary metabolites toxic products of mycotoxins especially are less known or emerging. Among these molecules the family of beauvericin and fusaproliferin are certainly the most interesting ones. This review aims to summarize the reported data and analyse the methodologies to extract and quantify beauvericin and fusaproliferin in food matrices
Influence of individual nutritional status on salivary endocannabinoids and N-acylethanolamines upon food mastication in vitro Lucia De Luca, Rosalia Ferracane, Paola Vitaglione
No full textEndocannabinoidi, N-aciletanolammine e N-acilfosfatidiletanolammine: banca dati alimentare ed introito attraverso una Dieta Mediterranea, Vegetariana e Occidentale Lucia De Luca, Rosalia Ferracane, Paola Vitaglione
No full textMultitoxin extraction and detection of thricotecenes in cereals: an improved LC-MS/MS approach
No full textMany multiresidual methods to evaluate natural occurrence of Fusarium toxins are already reported in scientific literature but a new rapid, reliable, cost-efficient and high sensitivity method for the simultaneous determination of several fusariotoxins is always welcome. Nivalenol, deoxynivalenol, fusarenon-X, 3-acetyldeoxynivalenol, diacetoxyscirpenol, HT-2 toxin, T-2 toxin, neosolaniol, zearalanone and zearalenone belong to the most common mycotoxins in food matrices grains, e.g wheat and maize. The proposed method is a multitoxin analytical method that combines high-performance liquid chromatography (HPLC), Atmospheric Pressure Chemical Ionization (APCI), triple quadrupole tandem mass spectrometry (LC-MS/MS) under the selected reaction monitoring (SRM) mode, and it is focused on the optimization of the sample preparation without the need for any clean-up.
Three different methods for sample preparation and for the simultaneous extractions of the above mentioned fusariotoxins were tested: two of these were followed by a different clean-up step for comparison, while the extraction method proposed in this work, that uses an 84% (v/v) acetonitrile aqueous solution, sample homogenization and subsequent filtration, was validated without any further clean-up step.
Calibration curves for all analytes are linear, except DAS, HT-2 and ZON, over the working range of 10-1000 μg/kg. The calibration curve of DAS was linear between 10-500 μg/kg, although the curves of HT-2 and ZON were linear in the range 10-250 μg/kg. Squared correlation coefficients (R2) were in the range 0.995-0.998 for the all point calibration curves. The lowest LODs were found for DON and ZAN with 0.5 μg/kg and 0.2 μg/kg, respectively, while the highest LODs were obtained for NIV, FUS-X and NEO with 3.3 μg/kg for each toxin
Profiling chicory sesquiterpene lactones by high resolution mass spectrometry
No full textSesquiterpene lactones (SLs) are the main determinants of radicchio bitterness and the control of their concentrations is a key point for the market value of this product. An innovative analytical approach based on two complementary mass spectrometers, Orbitrap-HRMS and MS/MS, was used for quantitative analysis of SLs in aerial part of four different varieties of chicory. Data highlighted the presence of eight SLs: 11β,13-dihydrolactucin, lactucin, 8-deoxy-lactucin, dihydro-8-deoxylactucin, dihydrolactucopicrin, lactucopicrin, lactuside C (jaquinellin glucoside) and dihydro-lactucopicrin oxalate. Significant varietal differences were found. The highest amount of SLs was found in the radicchio “Treviso Precoce” variety (189.71 μg/g), the lowest amount in “Treviso Tardivo” variety (45.78 μg/g). Lactucopicrin was the most abundant compound with concentration ranged between 99.36 in “Treviso Precoce” and 13.50 μg/g in “Treviso Tardivo” while dihydro-lactucopicrin oxalate was the less abundant in all analyzed varieties with an average concentration of about 1% on the total amount of SLs
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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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