1,720,954 research outputs found

    Characterisation and quantification of microstructure, physicochemical and functional properties of oven and forced convection continuous tumble roasted cereal grains

    Get PDF
    The use of roasted cereal grains in foods can improve organoleptic properties, enhance shelf life, ease incorporation into ready-to-eat products and increase antioxidant activity. Structural, physicochemical and functional changes will inevitably occur during roasting and this study aimed to investigate these properties. X-ray micro-computed tomography (μCT) was used as a nondestructive technique for characterising and quantifying microstructural changes in individual cereal grains induced by conventional oven and forced convection continuous tumble (FCCT) roasting at 180°C for 140 s. X-ray μCT uses differences in X-ray attenuation arising from differences in density within a sample. X-ray tomograms of the raw and roasted wheat and maize kernels were obtained, using a General Electric Phoenix model V|Tome|X L240 X-ray μCT system with a source voltage of 60 kV and an electron current set at 240 μA. Analysis of the whole kernel and regions-of-interest (ROIs) was performed with VGStudio Max 2.2 three-dimensional (3D) software. Qualitative results were depicted as two-dimensional (2D) transmission images and 3D volumes. Internal structural changes were observed as a loss of endosperm integrity, detected as a decrease in attenuation. For both cereal grains oven roasting was associated with a larger increase in kernel volume (wheat=4.47%; maize=10.76%) than FCCT roasting (wheat=1.57%; maize=3.41%), as well as larger relative density decreases (wheat=2.76%; maize=6.33%) in comparison to FCCT roasting (wheat=0.55%; maize=1.92%). During FCCT roasting the material density (excluding air) remained unaffected. Structural changes can strongly influence physicochemical and functional properties. Kernel hardness and hectolitre mass (HLM) can be helpful to assess the milling yield, which was not affected (P>0.05) by either roasting methods. Scanning electron microscopy (SEM) illustrated the starch-protein morphology, where both roasting methods resulted in a partially disintegrated protein network and swollen and/or ruptured starch granules in the oven-roasted samples. Quantification of these structural differences included crystallinity determinations using X-ray diffraction (XRD), thermal properties using differential scanning calorimetry (DSC) and pasting properties employing a Rapid Visco Analyser (RVA). The reduction in crystallinity for both FCCT (wheat=0.12%; maize=0.45%) and oven (wheat=0.16%; maize=1.83%) roasting was consistent with the decrease in gelatinisation enthalpy (ΔH). Only partial gelatinisation occurred in both the oven (wheat=17.16%; maize=25.27%) and FCCT-roasted (wheat=10.14%; maize=16.23%) samples. Oven roasting caused more adverse changes in most of the measured properties, being a more destructive process. With FCCT roasting the samples are continuously moving, resulting in an even heat transfer in comparison to oven roasting where the samples are stationary. FCCT roasting maintained more of the favourable characteristics, i.e. microstructure, hardness and milling yield and will thus result in a more acceptable final product. This study demonstrated the capability of X-ray μCT in combination with image analysis as a non-invasive technique to study microstructural changes in cereal grains, induced by roasting, both in a qualitative and quantitative manner and at a relatively high spatial resolution of 12 micron. The results integrate qualitative and quantitative information that could be useful for understanding structure-property relationships in terms of further processing and utilisation, e.g. the development of value-added products with improved digestibility and viscosity or delayed staling phenomenon.National Research Foundatio

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Get PDF
    The 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 PDF
    We 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 PDF
    We 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

    Author Index

    No full text
    Nao informado

    koamabayili/VECTRON-author-checklist: VECTRON author checklist

    No full text
    We 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 Under Sail The Imagination of Jack London, 1893-1902

    No full text
    In 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
    corecore