1,720,954 research outputs found
Quality grade evolution and health claim fulfillment of olive oils under simulated domestic consumption: kinetic modelling and shelf life predictions
No full textMestrado de dupla diplomação com a Université Libre de TunisOlive oil has always played a vital role in the Mediterranean diet, well renowned for its
nutritional properties and related health benefits. This is largely attributed to its high
concentration of monounsaturated fatty acids and bioactive minor compounds, such as
polyphenols. This study aimed to assess how typical household consumption conditions
influence the physicochemical and sensory properties of extra virgin olive oil (EVOO), as well
as its compliance with the European Union (EU) health claim. The results of the analysis of ten
bottles stored in darkness and exposed to light under simulated household conditions,
demonstrated an increase in PV and extinction coefficients over the 9-week period, with a more
pronounced rise in the light-exposed samples. In these samples, PV increased by 81.2%, and at
6 weeks it exceeded the legal EU thresholds for EVOO/VOO classification. In contrast, oils
stored in darkness kept all physicochemical parameters within legal limits allowing EVOO or
VOO classification, up to or beyond the seventh week, respectively. Also, by the eighth week,
sensory analysis revealed the presence of rancid in light-exposed samples, with intensities
ranging from 3.6 to 6.1, indicating advanced oxidation and rendering the oil unsuitable for
consumption (lampante oil). Kinetic models were developed to predict the shelf life (SL) of
commercial grade EVOO under household conditions, applying zero-, first-, and second-order
kinetic models for PV, K232, and K268 in both dark and light storage conditions. The models
fitted well the experimental data (R-Pearson values ranging from 0.89 to 0.97), with PV
emerging as the most sensitive SL indicator under these conditions. The estimated SL was
approximately 15 days for light-exposed oils and 63 days for oils stored in darkness. The
greatest variation in SL predictions, based on PV, K232, or K268, was observed in the light-
exposed samples. Photo-oxidation led to a rapid increase in PV, in contrast to the slower rise in
extinction coefficients, which are associated with secondary oxidation products that form when
oxygen availability diminishes. Regarding the health claim, the content of hydroxytyrosol and
tyrosol derivatives remained relatively stable throughout the 9-week period in both dark- and
light-stored oils, ranging from 12 to 13 mg/20 g of oil, significantly exceeding the minimum
required by the EU regulation. In conclusion, typical household conditions significantly impact
the quality of olive oil. Storing olive oil in darkness can extend its SL by 3 to 4 times, compared
to light-exposed conditions, in terms of maintaining its EVOO classification.O azeite sempre desempenhou um papel vital na dieta mediterrânica, bem conhecida pelas suas
propriedades nutricionais e benefícios para a saúde. Este facto é largamente atribuído à sua
elevada concentração de ácidos gordos monoinsaturados e de compostos menores bioativos,
como os polifenóis. Este estudo teve como objetivo avaliar de que forma as condições típicas
de consumo doméstico influenciam as propriedades físico-químicas e sensoriais do azeite
virgem extra (AVE), bem como a sua conformidade com a alegação de saúde da União Europeia
(UE). Os resultados da análise de dez garrafas armazenadas na escuridão e expostas à luz em
condições domésticas simuladas demonstraram um aumento dos coeficientes de extinção e do
IP ao longo do período de 9 semanas, com um aumento mais pronunciado nas amostras expostas
à luz. Nestas amostras, o IP aumentou 81.2% e, às 6 semanas, excedeu os limiares legais da UE
para a classificação de AVE/AV. Em contrapartida, os azeites armazenados na escuridão
mantiveram todos os parâmetros físico-químicos dentro dos limites legais que permitem a
classificação de AVE ou AV, até à sétima semana ou para além desta, respetivamente. Além
disso, na oitava semana, a análise sensorial revelou a presença de ranço nas amostras expostas
à luz, com intensidades que variam entre 3.6 e 6.1, indicando uma oxidação avançada e tornando
o azeite impróprio para consumo (azeite lampante). Foram desenvolvidos modelos cinéticos
para prever o tempo de vida útil (TVU) da classificação de AVE em condições domésticas,
aplicando modelos cinéticos de ordem zero, primeira e segunda para IP, K232 e K268 em
condições de armazenamento à luz e no escuro. Os modelos ajustaram-se bem aos dados
experimentais (valores de R-Pearson variando de 0.89 a 0.97), com o IP emergindo como o
indicador de TVU mais sensível nestas condições. A estimativa da TVU foi de
aproximadamente 15 dias para os azeites expostos à luz e de 63 dias para os óleos armazenados
no escuro. A maior variação nas previsões de TVU, com base no IP, K232 ou K268, foi observada
nas amostras expostas à luz. A foto-oxidação levou a um aumento rápido do IP, em contraste
com o aumento mais lento dos coeficientes de extinção, que estão associados a produtos de
oxidação secundários que se formam quando a disponibilidade de oxigénio diminui.
Relativamente à alegação de saúde, o teor de hidroxitirosol e derivados de tirosol manteve-se
relativamente estável ao longo do período de 9 semanas, tanto nos azeites armazenados no
escuro como nos azeites armazenados à luz, variando entre 12 e 13 mg/20 g de azeite,
excedendo significativamente o mínimo exigido pelo regulamento da UE. Em conclusão, as
condições domésticas típicas têm um impacto significativo na qualidade do azeite. O armazenamento do azeite no escuro pode prolongar a sua TVU 3 a 4 vezes, em comparação
com as condições de exposição à luz, em termos de manutenção da sua classificação AVE.This work was supported by national funds through FCT/MCTES (PIDDAC) : CIMO, This work was supported by national funds through FCT/MCTES (PIDDAC) :
CIMO, UIDB/00690/2020 (DOI: 10.54499/UIDB/00690/2020) and UIDP/00690/2020
(DOI: 10.54499/UIDP/00690/2020); and SusTEC, LA/P/0007/2020 (DOI:
10.54499/LA/P/0007/2020).
Agenda VIIAFOOD - Platform for Valorization, Industrialization and Commercial
Innovation in Agrifood project (No. C644929456-00000040) funded by the Recovery and
Resilience Plan. (DOI: 10.54499/UIDB/00690/2020) and UIDP/00690/2020 (DOI: 10.54499/UIDP/00690/2020); and SusTEC, LA/P/0007/2020 (DOI:
10.54499/LA/P/0007/2020).
Agenda VIIAFOOD - Platform for Valorization, Industrialization and Commercial Innovation in Agrifood project (No. C644929456-00000040) funded by the Recovery and Resilience Plan
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
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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