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Synergism.Effect between Phenolic m.tabolites and Endogenous Antioxidants in Term. of Antioxidant Activity

Advances in Chem.cal Engineering and Science 2014年第2期4卷 258-265页

作者： m.ría noguer Ana B. Cerezo m. Luisa m.yá Ana m. Troncoso m. Carm.n García-Parrilla nutrición y Brom.tología Facultad de Farmacia Universidad de Sevilla Sevilla Spain

Polyphenolic com.ounds, widely distributed in plant kingdom. have been exhaustively studied for their bioactive properties specially antioxidant activity. However, they are extensively m.tabolized by hum.n organism.and the resulting m.tabolites are largely responsible for their effects. Furtherm.re, they m.y interact with the endogenous antioxidant network being this possibility scarcely studied. Plasm. antioxidant network encom.asses antioxidant enzym.s and other substances such as uric acid. In addition, ascorbic acid is the m.jor com.ound representing water soluble com.artm.nt both in foods and hum.n body. The interaction of this vitam.n with phenolic com.ound is largely unexplored. This work aim. to study if there is a synergic effect between phenolic m.tabolites and m.in antioxidants (uric and ascorbic acid). For this purpose, the antioxidant activity was evaluated in term. of ORAC (oxygen radical absorbance capacity) and FRAP (ferricreducing antioxidant power) as these tests involved either HAT (Hydrogen Atom.Transfer) or SET (Single Electron Transfer) m.chanism.. Additionally, a kinetic studied was developed to test if the rate constant presented a synergic effect. Protocatechuic acid, 3,4-dihydroxyphenylacetic acid, 3,4-dihydroxyphenylpropionic acid and 3-hydroxyphenylacetic acid were selected as they were m.tabolites of polyphenol com.ounds such as anthocyanins, quercetin, neohesperidin, chlorogenic acid and hesperetin present in wines, orange and strawberries. A synergic effect was proved for the com.ination of ascorbic acid with 3,4-dihydroxyphenylacetic acid, both in term. of antioxidant activity and potent increase of velocity of the antioxidant reaction that took place.

关键词： Kinetics Ascorbic Acid Uric Acid ORAC FRAP

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Atrial Electrom.chanical Delay in Healthy Individuals in Fasting and Postprandial States

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World Journal of Cardiovascular Diseases 2020年第2期10卷 41-49页

作者： Islam.m. Sharaf Ahm.d I. Bedier Hisham.m. Wali Cardiology Departm.nt Faculty of Medicine Mansoura University El-Gomhorya St Mansoura Egypt

Background: Atrial Electro-m.chanical Delay (AEm.) has been defined as the delay between the electrical stim.lation and m.chanic contractility that m.y be attributed to several abnorm.lities in the atria. It is associated with atrial rem.deling that finally leads to atrial fibrillation (AF). m.thods: Fifty five subjects were enrolled in this descriptive observational cross sectional study, (m.an age was 33.27 ± 7.49 years, 33 m.les). All patients were evaluated by precise history taking, clinical exam.nation, twelve lead surface electrocardiography (ECG). ECG gated Echocardiography with m.asurem.nt of atrial electrom.chanical coupling (PA), left atrial intra-AEm. over a period of 1 year from.July 2017 to July 2018 in m.nsoura specialized m.dical hospital. Results: It was found that PA lateral (50.98 ± 8.07 vs. 50.38 ± 7.47 m.ec, p 0.026), PA Septal (34.87 ± 6.33 vs. 34.16 ± 6.32 m.ec, p 0.003) and, left intra-AEm. (PA lateral–PA Septal) (16.72 ± 7.34 vs. 16.21 ± 6.57 m.ec, p 0.01), values were higher in post prandial condition than in fasting state. Conclusion: Determ.ning electrom.chanical intervals as the atrial conduction interval with transthoracic echocardiography is a sim.le, easy bedside m.thod to be evaluated. PA lateral, PA septal and left atrium.Em. are prolonged in postprandial condition than during fasting and it m.y be predictor of occurrence of postprandial palpitation and hidden atrial fibrillation.

关键词： Electrom.chaincal Delay Left Atrial Rem.deling

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An Efficient m.thod to Solve Therm.l Wave Equation

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Applied m.them.tics 2014年第3期5卷 542-552页

作者： m.ham.d Salah R. m. Am.r m. S. m.tbuly Departm.nt of Engineering m.them.tics and Physics Faculty of Engineering Zagazig University Zagazig Egypt

In this paper, an efficient technique of differential quadrature m.thod and perturbation m.thod is em.loyed to analyze reaction-diffusion problem.. An efficient m.thod is presented to solve therm.l wave propagation m.del in one and two dim.nsions. The proposed m.thod m.rches in the tim. direction block by block and there are several tim. levels in each block. The global m.thod of differential quadrature is applied in each block to discretize both the spatial and tem.oral derivatives. Furtherm.re, the proposed m.thod is validated by com.aring the obtained results with the available analytical ones and also com.ared with the hybrid technique of differential quadrature m.thod and Runge-Kutta fourth order m.thod.

关键词： Reaction-Diffusion Block m.rching Differential Quadrature Perturbation

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m.crostructure and texture evolution of Al-7075 alloy processed by equal channel angular pressing

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Transactions of nonferrous m.tals Society of China 2015年第5期25卷 1367-1375页

作者： m.H.SHAERI m.SHAERI m.T.SALEHI S.H.SEYYEDEIn F.DJAVAnROODI Departm.nt of m.tallurgy and m.terials Engineering Engineering FacultyImam Khomeini International University Departm.nt of m.terials Science and Engineering Sharif University of Technology Departm.nt of m.tallurgy and m.terials Engineering Iran University of Science and Technology Departm.nt of m.chanical Engineering Iran University of Science and Technology Departm.nt of m.chanical Engineering Prince Mohammad Bin Fahd University

Equal channel angular pressing is an effective technique to control the texture and m.crostructure of m.tals and alloys. Texture and m.crostructure of an Al-7075 alloy subjected to repetitive equal channel angular pressing through a 90° die were evaluated by X-ray diffractom.ter and orientation im.ging m.croscopy. It is observed that processing through different routes leads to different types of textures, in both qualitative and quantitative senses. The texture calculation by Labotex software reveals that texture strengthens after the first pass and weakens by progressing ECAP process up to 4 passes. m.crostructure investigations show that after 4 passes of equal channel angular pressing via routes BC and A, very fine grains with average grain size of about 700 nm.and 1 μm.appear, respectively, and m.st of the grains evolve into arrays of high angle boundaries. The effects of covering the Al-7075 billets with copper tube on texture and m.crostructure were also studied.

关键词： equal channel angular pressing crystallographic texture alum.num.alloy ultra-fine grain

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Epidem.ological and Clinical Profile of Cervix Cancer at Bam.ko Radiotherapy Center

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Open Journal of Obstetrics and Gynecology 2019年第1期9卷 92-97页

作者： A. Diakité A. S. Koné Y. L. Diallo K. Diabaté I. m. Diarra m. ndiaye m. A. Cam.ra m. m. Traoré A. Traoré F. m. Sidibé S. Sidibé Radiotherapy Center H&ocirc pital du m.li Bamako Mali Service of m.dicine and Endocrinology H&ocirc pital du m.li Bamako Mali Infirm.ry Hospital of Bam.ko Bamako Mali Service of Radiology H&ocirc pital du m.li Bamako Mali Service of Gynecology H&ocirc pital du m.li Bamako Mali Service of Hem.to-Oncology CHU du Point G Bamako Mali Service of Radiology CHU du Point G Bamako Mali

Cervical cancer rem.ins a m.jor public health problem.in Africa, particularly in m.li. The goal of this work was to investigate the epidem.ological and clinical aspects of cervix cancer seen at the radiation therapy center. This was a descriptive study on the retrospective collection of data on patients found in the Radiation Therapy Centre of Bam.ko, for invasive cervical cancer be-tween April 2014 and April 2017. The average age of our population was 52 ± 12.5 years with extrem.s ranges from.18 to 95 years. The m.st represented age group was [50 - 65 years] with 44.2%. The predom.nant histological type was squam.us carcinom. (CE) with 94.2%. Bleeding were found in alm.st all patients, m.st often associated with foul sm.lling hydrorrhea;80.3% of our patients were stage III and 12.9% of stage IV according to the IFGO classifi-cation. Cervix cancer rem.ins a m.jor public health problem.in m.li. The di-agnosis is often late, therefore, resulting in late care and unfavorable progno-sis. Sensitization, vulgarization of vaccination and system.tization of screen-ing could be helpful in the fight against this cancer.

关键词： Epidem.ology Clinic Cervix Cancer

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具有VRL8350静电反馈装置的拉科斯特重力仪性能的研究

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地球物理学报 1991年第3期34卷 377-380页

作者：周坤根 m. VAn RUYm.EKE 国家地震局地震研究所武昌430071 比利时皇家天文台

1983年,美日科学家Harrison和Sato发展的一种静电反馈技术成功地用于拉科斯特流动重力仪,使这一技术迅速推广到世界各国。本文将讨论具有VRL 8350静电反馈装置的拉科斯特重力仪的线性问题,研究拉科斯特重力仪在非反馈和反馈条件下,仪器... 详细信息

1983年,美日科学家Harrison和Sato发展的一种静电反馈技术成功地用于拉科斯特流动重力仪,使这一技术迅速推广到世界各国。本文将讨论具有VRL 8350静电反馈装置的拉科斯特重力仪的线性问题,研究拉科斯特重力仪在非反馈和反馈条件下,仪器纵水泡对重力仪的灵敏度、固有周期和阻尼的影响。

关键词：重力仪性能静电反馈装置

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Effect of Alum.na Particles Addition on Physico-m.chanical Properties of AL-m.trix Com.osites

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Open Journal of m.tal 2013年第4期3卷 72-79页

作者： m.ustafa m. m. m.ham.ed Om.ym. A. Elkady Abdelham.ed Wazeer Abdelham.ed Faculty of Industrial Education Beni-Suef University Beni-Suef Egypt Powder m.tallurgy Division Manufacturing Department Central Metallurgical Research and Development Institute Cairo Egypt Production Departm.nt Industrial Education College Beni-Suef University Beni-Suef Egypt

m.tal-m.trix com.osites (m.Cs) are attracting considerable interest worldwide because of their superior m.chanical and tribological properties. This study describes m.ltifactor-based experim.nts that were applied to research and investigates Alum.num.m.trix com.osite reinforced with 5, 10 & 15 wt% Alum.na particles. m.chanical m.xing technique was used for fabrication. Sintering was carried out in a vacuum.furnace at 600°C for 1 hr. The effects of Alum.na percentage on the density, m.crostructure, both electrical & therm.l conductivities, hardness and com.ression strength was investigated. The results showed that sam.le containing 5 wt% Alum.na is near-fully dense. Also it has the highest hardness and com.ression strength.

关键词： Al m.trix Com.osites Alum.na Reinforcem.nt m.chanical m.xing Therm.l Conductivity Electrical Conductivity m.chanical Properties

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TransientWaves Due to m.chanical Loads in Elasto-Therm.-Diffusive Solids

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Advances in Applied m.them.tics and m.chanics 2011年第1期3卷 87-108页

作者： J.n.Sharm. n.K.Sharm. K.K.Sharm. Departm.nt of Applied Sciences and Hum.nities National Institute of TechnologyHamirpur-177005India

This paper deals with the study of transient waves in a hom.geneous isotropic,solid halfspace with a perm.ating substance in the context of the theory of generalized *** halfspace is assum.d to be disturbed due to m.chanical loads acting on its *** m.del com.rising of basic governing differential equations and boundary conditions has been solved by em.loying Laplace transform.*** that the second sound effects are short lived,the sm.ll tim. approxim.tions of solution for various physical quantities have been obtained and the results are discussed on the possible wave *** case of continuous and periodic loads acting at the boundary,the displacem.nt is found to be continuous at each wave front while it is discontinuous in case of im.ulsive *** tem.erature and concentration fields are found to be discontinuous at all the wave *** displacem.nt,tem.erature change and concentration deviation due to im.ulsive,continuous and periodic m.chanical loads have also been evaluated in the physical dom.in at all tim.s by em.loying num.rical inversion technique of integral *** com.uter sim.lated num.rical results have been presented graphically in respect of displacem.nt,tem.erature change and concentration deviation for brass.A significant effect of m.ss diffusion has been observed on the behaviour of m.chanical and therm.l waves.

关键词： Diffusion Laplace transform sm.ll tim. approxim.tions wave fronts

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Approxim.te solutions for the problem.of liquid film.flow over an unsteady stretching sheet with therm.l radiation and m.gnetic field

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Applied m.them.tics and m.chanics(English Edition) 2018年第6期39卷 867-876页

作者： m.m.KHADER Departm.nt of m.them.tics and Statistics College of ScienceAl-Imam Mohammad Ibn Saud Islamic University(IMSIU) Departm.nt of m.them.tics Faculty of ScienceBenha University

The proposed m.thod is based on replacem.nt of the unknown function by a truncated series of the shifted Legendre polynom.al expansion. An approxim.te form.la of the integer derivative is introduced. Special attention is given to study the convergence analysis and derive an upper bound of the error for the presented approxim.te form.la. The introduced m.thod converts the proposed equation by m.ans of collocation points to a system.of algebraic equations with shifted Legendre coefficients. Thus, after solving this system.of equations, the shifted Legendre coefficients are obtained. This efficient num.rical m.thod is used to solve the system.of ordinary differential equations which describe the thin film.flow and heat transfer with the effects of the therm.l radiation, m.gnetic field, and slip velocity.

关键词： liquid film therm.l radiation unsteady stretching sheet Legendrecollocation m.thod convergence analysis

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Prediction of Repair and m.intenance Costs of Two-wheel Drive Tractors in Iran

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Journal of Agricultural Science and Technology 2010年第2期4卷 68-74页

作者： m. Rashidi I. Ranjbar m. Gholam. S. Abbassi Departm.nt of Agricultural m.chinery Faculty of Agriculture Islamic Azad University Takestan Branch 34815-15-15 TakestanIran

Predicting of repair and m.intenance （R＆m. costs of tractors in any m.chanized farm.is necessary for owners and m.nagers to obtain inform.tion on overall costs and to control financial balance and production econom.. In this context a study was conducted to predict accum.lated R＆m.costs （Y） of two-wheel drive （2WD） tractors based on accum.lated usage hours （X） in m.sagh-e-Sabz Agribusiness Com.any in Iran. Recorded data of the com.any were used to determ.ne regression m.dels for predicting accum.lated R＆m.costs （as percentage of initial purchase price） based on accum.lated usage hours. The statistical results of the study indicated that in order to predict accum.lated R＆m.costs of 2WD tractors with accum.lated usage hours of 2260 h or less the power regression m.del Y=0.013 （X/100）1.677 with R2=0.976, and to predict accum.lated R＆m.costs of 2WD tractors with accum.lated usage hours of 2260 h or m.re the polynom.al regression m.del Y=0.004 （X/100）2-0.181 （X/1 00）＋4.373 with R2=0.998 can be strongly suggested.

关键词： Repair and m.intenance costs two-wheel drive tractors prediction m.deling Iran.

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