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Interval oscillation criteria for forced Emden-Fowler functional dynamic equations with.oscillatory potential

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Science Ch.na Math.matics 2013年第3期56卷 561-576页

作者： ANDERSON Douglas R. saker samir h. Department of Math.matics and Computer Science Concordia College Department of Math.matics Faculty of Science Mansoura University

Interval oscillation criteria are establish.d for a second-order functional dynamic equation of Emden-Fowler type with.oscillatory potential by applying Riccati and generalized Riccati tech.iques. Th. results represent furth.r improvements on th.se given even for differential and difference equations. Some examples are considered to illustrate th. main results.

关键词： oscillation forced dynamic equations time scales functional equations Riccati tech.ique

Oscillation Th.orems for Second-Order Nonlinear Neutral Delay Dynamic Equations on Time Scales

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Acta Math.matica Sinica,English.Series 2008年第9期24卷 5-1432,1410页

作者： samir h.saker Donal O’REGAN Ravi P.AGARWAL Department of Math.matics College of Science King Saud University Riyadh 11451 Saudi Arabia Department of Math.matics National University of Ireland Galway Ireland Department of Math.matical Sciences Florida Institute of Technology Melbourne Florida 32901 USA

By employing th. generalized Riccati transformation tech.ique,we will establish.some new oscillation criteria and study th. asymptotic beh.vior of th. nonoscillatory solutions of th. second-order nonlinear neutral delay dynamic equation [r(t)[y(t)+p(t)y(■(t))]~Δ]~Δ+q(t)f(y((δ(t)))=0 on a time scale■.Th. results improve some oscillation results for neutral delay dynamic equations and in th. special case wh.n■our results cover and improve th. oscillation results for second- order neutral delay differential equations establish.d by Li and Liu[***.,48(1996), 871 886].Wh.n■,our results cover and improve th. oscillation results for second order neutral delay difference equations establish.d by Li and Yeh.***.,36(1998),123-132].Wh.n ■ ■our results are essentially *** examples illustrating our main results are given.

关键词： oscillation neutral delay dynamic equation generalized Riccati tech.ique time scales

ON Th. GLOBAL STABILITY CONJECTURE OF Th. GENOTYPE SELECTION MODEL

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Acta Math.matica Scientia 2011年第2期31卷 512-528页

作者： S.h. saker Department of Math.matics King Saud University Department of Math.matics Faculty of Science Mansoura University

In 1994, Grove, Kocic, Ladas, and Levin conjectured th.t th. local stability and global stability conditions of th. fixed point -y= 1/2 in th. genotype selection model sh.uld be equivalent. In th.s article, we give an affirmative answer to th.s conjecture and prove th.t local stability implies global stability. Some illustrative examples are included to demonstrate th. validity and applicability of th. results.

关键词： Local stability global stability discrete genotype selection model

OSCILLATION AND GLOBAL ATTRACTIVITY OF IMPULSIVE PERIODIC DELAY RESPIRATORY DYNAMICS MODEL

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Ch.nese Annals of Math.matics,Series B 2005年第4期26卷 511-522页

作者： S.h.saker Department of Math.matics Faculty of ScienceMansoura UniversityMansoura 35516Egypt

Th.s paper studies th. nonlinear delay impulsive respiratory dynamics model. Th. model describes th. sudden ch.nges of th. concentration of CO2 in th. blood of th. mammal. It is proved th.t th. model h.s a unique positive periodic solution. Somesufficient conditions for oscillation of all positive solutions about th. positive periodic solution are establish.d and also some sufficient conditions for th. global attractivityof th. periodic solution are obtained.

关键词： Periodic solutions Oscillation Global attractivity Respiratory dynamics model Impulsive differential equation

Oscillation of Second Order Nonlinear Delay Damped Difference Equations

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Acta Math.matica Sinica,English.Series 2007年第4期23卷 715-722页

作者： S.h.saker B.G.Zh.NG Department of Math.matics Faculty of ScienceMansoura UniversityMansoura 35516Egypt Department of Math.matics Ocean University of ChinaQingdao 266071P.R.China

Some new oscillation criteria for nonlinear delay difference equation with.damping △^2xn＋pn△xn＋F（n,x（n-τ,△x（n-σ）=0,n=0,1,2,…,（＊）are given. Our results partially solve th. open problem posed in [Math. Boh.mica, 125 （2000）, 421- 430]. Also, we will establish.some new oscillation criteria for special cases of （＊）, wh.ch.improve some of th. well-known results in th. literature.

关键词： oscillation second-order difference equations Riccati tech.iques

Study of th. Different Factors Th.t Influence Jet Pump Performance

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Open Journal of Fluid Dynamics 2013年第2期3卷 44-49页

作者： A. A. saker h. Z. h.ssan Public Auth.rity of Applied Education and Training Kuwait City Kuwait

Th. objective of th.s work is to study experimentally th. ch.racteristics of jet pump. Suction h.ad, driving air pressure and th. percentage of th. distance between th.oat section and nozzle are recorded. Th. effect of each.parameter on th. pump performance is investigated, in order to h.ve a better understanding about th. beh.vior of such.pump under various conditions. A simple geometry jet pump was designed, developed and tested. Th. experiments sh.w th.t we sh.uld be careful in increasing th. suction h.ad, and stability must be considered between th. suction h.ad and th. driving air mass flow rate. Wh.le th. effect of increasing Pa will stop at certain maximum of th. ratio of th. mass flow rate of water to air (M), th.t is any increase in Pa will meet no ch.nge in M. Wh.le increasing S/Dth.will leads to decrease in th. percentage of M because th. optimum S/Dth.= 0.5 so th.t at th.s value we will h.ve th. best performance and any oth.r values for S/Dth.th. percentage M will decreases, but th.s effect is not so clear and it could be neglected. Th. pump performance is not so sensitive with.th. ch.nge of S/Dth.after S/Dth.= 0.5. Also th.s information will h.lp improving and extending th. use of th. jet pump in many practical applications.

关键词： Jet Pump Nozzle-Th.oat Interface Driving Air Pressure

NEW DYNAMIC INEQUALITIES FOR DECREASING FUNCTIONS AND Th.OREMS OF h.Gh.R INTEGRABILITY

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Annals of Applied Math.matics 2018年第2期34卷 165-177页

作者： S.h.saker D.O'Regan M.M.Osman R.P.Agarwal Dept.of Math. Faculty of Science Mansoura University Sch.ol of Math. Statistics and Applied Math. National University of Ireland Dept.of Math. Texas A & M University-Kingsvilie

In th.s paper we establish.some new dynamic inequalities on time scales wh.ch.contain in particular generalizations of integral and discrete inequalities due to h.rdy, Littlewood, Polya, D＇Apuzzo, Sbordone and Popoli... 详细信息

关键词： reverse h.lder's inequality Geh.ing class h.gh.r integrability h.rdy-Littlewood-Polya inequality time scales

肺动脉高压中骨桥蛋白是衰老肺血管细胞表达的重要介质

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中华高血压杂志 2016年第9期24卷 862-862页

作者：刘莉叶鹏 saker M Lipskaia L Marcos E Abid S Parpaleix A h.ussaini A Validire P Girard P Noureddine h.Boyer L Vienney N Amsellem V Marguerit L Maitre B Derumeaux G Dubois-Rande JL Jourdan-Lesaux C Delcroix M Quarck R Adnot S

衰老的肺动脉平滑肌细胞（pulmonaryarterysmooth.usclecells，PA-SMC）可通过产生分泌因子促进肺高血压的发病。该研究的目的是探讨由衰老的PA-SMC释放的细胞外基质蛋白在肺高血压中的作用。方法：对正进行复制的衰老的人类PA-SMC进行... 详细信息

衰老的肺动脉平滑肌细胞（pulmonaryarterysmooth.usclecells，PA-SMC）可通过产生分泌因子促进肺高血压的发病。该研究的目的是探讨由衰老的PA-SMC释放的细胞外基质蛋白在肺高血压中的作用。方法：对正进行复制的衰老的人类PA-SMC进行聚合酶链反应阵列分析，发现骨桥蛋白上调，其介导了衰老PA-SMC介质和基质的刺激作用，以及对PA-SMC生长和迁移的作用。

关键词：骨桥蛋白肺血管肺动脉高压衰老细胞表达介质细胞外基质蛋白肺动脉平滑肌细胞