895 research outputs found
Identifications of polyphenols and quantification of anthocyanidins in grapes and grape-derived products
No full textPolyphenols in grapes and grape-derived products have attracted public and scientific attention due to their numerous protective roles to human health. A rapid and comprehensive qualitative method was developed to characterize the different classes of polyphenols, such as anthocyanins, flavonols, phenolic acids and flavanols/proanthocyanidins, in grapes and grape-derived products. The detection was achieved by two runs with same HPLC gradient in different MS ionization modes and mobile phase modifiers (positive mode and 0.4% trifluoroacetic acid for anthocyanins and flavonols, negative mode and 0.1% formic acid for phenolic acids and flavanols). Under the optimized LC/MS conditions and based on the analysis of the MS and UV data and in comparison with the authenticated standards, a total of 53 polyphenolic compounds were successfully separated and individually identified including 33 anthocyanins, 12 flavonols, 4 phenolic acids and 4 flavanols/proanthocyanidins. With the method developed, a survey was conducted to qualitatively assess and compare the composition of polyphenols among 29 grapes and grape-derived products. To facilitate the quantitation of the major class of polyphenolic anthocyanidins, a simple and precise acid assisted hydrolysis method was established for the quantitation of anthocyanidins in grape juice samples, grape berries and grape skins using LC/MS. Five most common anthocyanidins of delphenidin, petunidin, cyanidin, malvidin, and peonidin in the hydrolyzed grape extracts were included in the quantification study. The validation of this method showed that the recovery percentages of five anthocyanidins ranged from 98.59 % to 103.20% with the relative standard deviation (RSD) less than 5.03%. The qualitative method provided complete insight into the composition of polyphenols in grapes, and other grape-derived products. This quantitative method provides a rapid and accurate tool to quantitatively study individual anthocyanidin in grapes or grape juice samples for quality control and to facilitate the evaluation and comparison of new commercial grapes or grape juice products in market.M.S.Includes bibliographical referencesby Yanping X
Supplemental Materials for AJP-GI (ID: GI-00273-2023R1)
No full textJournal title: AJP-Gastrointest Liver PhysiolManuscript Title: N-glycosylation of SCAP exacerbates hepatocellular inflammation and lipid accumulation via ACSS2-mediated histone H3K27 acetylation (ID: GI-00273-2023R1)Authors: Xuemei Li, Xiaoqin Tang, Yue Xiang, Zhibo Zhao, Yanping Li, Qiuying Ding, Linkun Zhang, Jingyuan Xu, Lei Zhao, Yao Chen.</p
Multiscale asymptotic method for Steklov eigenvalue equations in composite media
No full textAuthor name used in this publication: Yanping Lin2012-2013 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishedVoR allowe
Developing finite element methods for maxwell's equations in a cole-cole dispersive medium
No full textAuthor name used in this publication: Yanping Lin2011-2012 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishedVoR allowe
Multiscale asymptotic method for Maxwell's equations in composite materials
No full textAuthor name used in this publication: Yanping Lin2009-2010 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishedVoR allowe
Edge-unfolding almost-flat convex polyhedral terrains
No full textThesis (M. Eng.)--Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2013.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (pages 97-98).In this thesis we consider the centuries-old question of edge-unfolding convex polyhedra, focusing specifically on edge-unfoldability of convex polyhedral terrain which are "almost at" in that they have very small height. We demonstrate how to determine whether cut-trees of such almost-at terrains unfold and prove that, in this context, any partial cut-tree which unfolds without overlap and "opens" at a root edge can be locally extended by a neighboring edge of this root edge. We show that, for certain (but not all) planar graphs G, there are cut-trees which unfold for all almost-at terrains whose planar projection is G. We also demonstrate a non-cut-tree-based method of unfolding which relies on "slice" operations to build an unfolding of a complicated terrain from a known unfolding of a simpler terrain. Finally, we describe several heuristics for generating cut-forests and provide some computational results of such heuristics on unfolding almost-at convex polyhedral terrains.by Yanping Chen.M.Eng
Optimisation of Reverts Usage on Sintering Processes and Impact on the Sinter Quality: An experimental study into the mechanisms of sintering processes and production by utilising additives
No full textUtilisation of reverts in sinter production is nonetheless challenging considering physical and chemical characteristics: physical by means of presence of extreme amount of fine material (<1mm) and chemical in terms of heavy metals, alkalis and uneven distribution of materials. Poor granulation, affecting permeability and degrading of cold strength of produced sinter are negatively influencing sinter processes. On the other hand, reverts contain valuable materials as carbon- and iron-bearing materials, and can affect the sinter process positively. Steelmaking companies generate large quantities of reverts, however the impact of reverts on sinter processes and sinter quality is not fully investigated. With this in mind, this study investigates the impact of revert blends utilised in sinter blend on sinter processes and quality.Only abstract due to embarg
Educação moral no ensino de português como língua estrangeira na China: perspectivas e práticas no nível elementar
No full textRESUMO: Para promover o desenvolvimento integral dos alunos, a educação moral baseada no currículo, que integra a formação de valores à construção de conhecimentos e ao desenvolvimento de competências, tem sido um tema central nas reformas pedagógicas do ensino superior na China nos últimos anos. Este artigo tem como objetivo explorar práticas pedagógicas de educação moral no ensino de Português como Língua Estrangeira (PLE) no nível elementar, utilizando três abordagens principais: o ensino de fonética, a exploração de textos didáticos e a introdução à cultura lusófona. Ao longo do ano letivo de 2023-2024, foi implementada uma intervenção pedagógica numa disciplina optativa de Português Elementar na Universidade de Jilin, e a eficácia da educação moral foi avaliada por meio de observações em sala de aula e análises quantitativas e qualitativas dos questionários. Os resultados indicam que as três estratégias utilizadas—atividades de expansão fonética, exploração de elementos morais nos textos e introdução da cultura lusófona—não apenas enriqueceram o conteúdo curricular, como também contribuíram para uma formação mais integral dos alunos, unindo o desenvolvimento de competências linguísticas à interiorização de valores éticos. O estudo também identificou desafios, como a necessidade de sistematizar os elementos da educação moral e de criar materiais didáticos mais adequados para os diferentes níveis de PLE. Espera-se que este estudo contribua para a reflexão sobre a integração da educação moral no ensino de PLE
Desenvolvimento da compreensão oral em Português Língua Segunda com recurso a materiais semi-autênticos
No full textOral comprehension plays a crucial role in the development of the communicative competence of a foreign language. It is also considered to be the most difficult skill to learn due to its intrinsic nature. When it comes to the teaching and learning of oral comprehension in the classroom, the didactic materials are an indispensable element in carrying out activities. In this sense, using action research methodology, a project was developed with A1.2 level students, within the scope of the pedagogical internship of the Masters in Portuguese as Second Language/Foreign Language, of the Faculty of Arts of University of Porto, with the main objective of developing the oral comprehension of learners of Portuguese as a Second Language, through the creation of semi-authentic resources. After analysing the results, we can conclude that: i.) the application of the class model centred on oral comprehension - pre-activity, activity and postactivity - contributes not only to the success of the activity of oral comprehension, but also promotes the development of other competences, especially linguistic competence in the areas of oral expression and interaction; ii.) the audio and audiovisual materials created during the pedagogical intervention constitute an asset for the enrichment of didactic materials for the learners of Portuguese as a Second Language.La comprensión oral juega un papel crucial en el desarrollo de la competencia comunicativa en una lengua extranjera. También se considera la habilidad más difícil de aprender debido a su naturaleza intrínseca. Para la enseñanza y aprendizaje de la comprensión oral en el aula, los materiales didácticos de comprensión oral son un elemento indispensable en la realización de las actividades. En este sentido, utilizando la metodología de investigación-acción, se desarrolló un proyecto con estudiantes de nivel A1.2, en el marco de la pasantía pedagógica de la Maestría en Portugués como Lengua Segunda/Lengua Extranjera, en la Facultad de Artes de la Universidad de Porto, con el objetivo principal de desarrollar la comprensión oral de los estudiantes de Portugués como Lengua Segunda, a través de la creación de recursos semiauténticos. Analizando los resultados obtenidos, podemos afirmar que, i.) La aplicación del modelo de la clase centrada en la comprensión oral - pre-actividad, actividad y post-actividad contribuye no solo al éxito de la actividad de comprensión oral, sino también promueve el desarrollo de otras habilidades, especialmente la competencia lingüística en términos de expresión e interacción orales; ii.) los materiales de audio y audiovisuales creados durante la intervención pedagógica constituyen un activo para el enriquecimiento de los materiales didácticos destinados a los estudiantes de Portugués como Lengua Segunda.A compreensão oral assume um papel crucial no desenvolvimento da competência comunicativa de uma língua estrangeira. É também considerada como a competência mais difícil de aprender devido à sua natureza intrínseca. Para o ensino-aprendizagem da compreensão oral na sala de aula, os materiais didáticos de compreensão oral constituem um elemento indispensável na realização de atividades. Nesse sentido, com recurso a metodologia de investigação-ação, foi desenvolvido um projeto junto de alunos de nível A1.2, no âmbito do estágio pedagógico do Mestrado em Português Língua Segunda/Língua Estrangeira, da Faculdade de Letras da Universidade do Porto, com o objetivo principal de desenvolver a compreensão oral dos aprendentes de Português Língua Segunda, através da criação dos recursos semi-autênticos. Analisando os resultados obtidos, podemos afirmar que, i.) a aplicação do modelo da aula centrada na compreensão oral - pré-atividade, atividade e pós-atividade - contribui não só para o sucesso da atividade de compreensão oral, como promove também o desenvolvimento de outras competências, sobretudo a competência linguística nas vertentes da expressão e interação oral; ii.) os materiais áudio e audiovisuais criados ao longo da intervenção pedagógica constituem uma mais-valia para o enriquecimento de materiais didáticos destinados aos aprendentes de Português Língua Segunda
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