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Differentiation of Italian extra virgin olive oils by rapid evaporative ionization mass spectrometry
Full text linkCoumarins, Psoralens and Polymethoxyflavones in Cold-pressed Citrus Essential Oils: a Review
No full textCold-pressed Citrus essential oils namely lemon, bergamot, lime, grapefruit, mandarin, sweet and bitter orange are obtained from the peel of Citrus fruits. They were normally used in food, cosmetic, and pharmaceutical industries as ingredients. Essential oils extraction processes produce oils with different sensory qualities, and often these processes are expensive and have a low yield. For such a reason adulteration process are frequent, so careful attention must be paid to ensure the oils' genuineness and authenticity. Moreover, psoralen levels are continuously monitored by opinions and regulations released from International Fragrance Association and the European Parliament due to their photoactivity.
This review aims to browse the scientific literature of the past 30 years on the characterization of the non-volatile fraction of cold-pressed Citrus essential oils to discuss results achieved so far and highlight future prospect
essential oils by linear retention index approach applied to liquid chromatography coupled to photodiode array detector
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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
Apocarotenoids profiling in different Capsicum species
No full textThe present study report on the application of an on line supercritical fluid extraction-supercritical fluid chromatography-triple quadrupole/mass spectrometry methodology to the first apocarotenoids profiling of seventeen different chilli peppers cultivars belonging to Capsicum annuum, Capsicum baccatum and Capsicum chinense species. A total of 19 free apocarotenoids and 8 apocarotenoids fatty acid esters were identified; β-Apo-8'-carotenal and Apo-8'-zeaxanthinal were also quantified and the β-Apo-8'-carotenal occurrence was in the percentage ranges relative to β-carotene of 0.03-3.87%. PCA was performed as a multivariate display method on the quantified carotenoids and apocarotenoids, in order to visualize the data structure. Moreover, different ε-apoluteinals and 4-oxo-apo-β-carotenals were detected in Capsicum species also for the first time and, to the best of authors knowledge, in any food matrix
Comprehensive two-dimensional liquid chromatography: characterization of aqueous phase from pyrolysis of lignocellulosic biomasses
No full textComprehensive 2D-LC is a powerful analytical technique capable of delivering high separation power. Despite the use of reversed phase modes in both dimensions, a satisfactory degree of orthogonality was achieved by the employment of a smart design of gradient elution strategies in the second dimension
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
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