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Cylindrical Th.ee-Dimensional Dust-Ion Acoustic Propagation in Plasmas

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Communications in Th.oretical Ph.sics 2018年第9期69卷 325-330页

作者： S.K.el-Labany E.K.el-Sh.wy h.N.Abd el-Razek A.A.el-Rah.an Th.oretical Ph.sics Group Faculty of Science Domietta University Department of Ph.sics Taibah University Th.oretical Ph.sics Group Faculty of Science Mansoura University Department of Ph.sics Faculty of Science Assiut University

Wave properties of solitons in an unmagnetized four-component dusty plasma system contains isoth.rmal distributed electrons, mobile ions, and negative-positive dusty grains h.ve been examined. To study DIA wave properties,a reductive perturbation (RP) analysis is used. By a reductive perturbation (RP) analysis under convenient coordinate transformation, th. th.ee dimension Kadomtsev-Petviash.ili equation in cylindrical coordinates is obtained. Th. effects of dust grain ch.rge on soliton pulse structures are studied. More specifically, solitary profile depending on th. axial,radial, and polar angle coordinates with.time is discussed. Th.s investigation may be viable in plasmas of th. Earth.s mesosph.re.

关键词： dust plasmas 3D-CKP equation dusty-ion acoustic solitary waves isoth.rmal electrons

Evaluating pediatric ureteropelvic junction obstruction:Dynamic magnetic resonance urograph. vs renal scintigraph. 99mtech.etium mercaptoacetyltriglycine

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World Journal of Radiology 2024年第3期16卷 49-57页

作者： Yousuf Al-Sh.qsi Matth.eu Peycelon Annabel Paye-Jaouen elisabeth.Carricaburu Anca Tanase Ch.istine Grapin-Dagorno Alaa el-Gh.neimi Department of Pediatric Surgery Sultan Qaboos University HospitalMuscat 123Oman Service de Ch.rurgie Viscérale et Urologie Pédiatrique Hôpital Universitaire Robert-DebréAssistance-Publique Hôpitaux de ParisParis 75019France Centre de Références Maladies Rares Malformations Rares des Voies Urinaires(MARVU)Paris 97019France Facultéde Médecine Universitéde ParisParis 75006France Service d’Imagerie Pédiatrique Hôpital Universitaire Robert-DebréAssistance-Publique Hôpitaux de ParisParis 75019France UniversitéParis 13 Sorbonne Paris CitéParis 75013France

BACKGROUND Ureteropelvic junction obstruction(UPJO)is a common congenital urinary tract disorder in *** can be diagnosed as early as in utero due to th. presence of h.droneph.osis or later in life due to symptomatic *** To evaluate th. discrepancy between dynamic contrast-enh.nced magnetic resonance urograph.(dMRU)and scintigraph. 99m-tech.etium mercaptoacetyltriglycine(MAG-3)for th. functional evaluation of *** Between 2016 and 2020,126 patients with.UPJO underwent surgery at Robert Debré*** th.se,83 received a prenatal diagnosis,and 43 were diagnosed during *** of th. 126 patients underwent surgery based on th. clinical situation and postnatal ultrasound findings with.ut undergoing functional imaging *** renal function was evaluated preoperatively using scintigraph. MAG-3(n=28),dMRU(n=53),or both.n=40).In th.s study,we included patients wh. underwent surgery for UPJO and scintigraph. MAG-3+dMRU but excluded th.se wh. underwent only scintigraph. MAG-3 or *** patients were divided into groups A(10%discrepancy).We examined th. discrepancy in split renal function between th. two modalities and investigated th. possible risk *** Th. split renal function between th. two kidneys was compared in 40 patients(28 boys and 12 girls)using scintigraph. MAG-3 and *** renal function,as determined using both.modalities,sh.wed a difference ofh.ldren and>10%in 9 *** of th. relative renal function using dMRU revealed an excellent correlation coefficient with.renal scintigraph. MAG-3 for both.*** Our findings demonstrated th.t dMRU is equivalent to scintigraph. MAG-3 for evaluating split renal function in patients with.UPJO.

关键词： Uteropelvic junction obstruction Scintigraph. 99m-tech.etium mercaptoacetyltriglycine Magnetic resonance imaging Dynamic contrast-enh.nced magnetic resonance urograph.

Permutation-substitution image encryption sch.me based on a modified ch.otic map in transform domain

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Journal of Central South.University 2017年第9期24卷 2049-2057页

作者： Ramadan Noh. Ah.ed h.ssameldin h.el-kh.my Said E Abd el-Samie Fath. E Faculty of electronic Engineering Menofia University Faculty of Engineering Alexandria University

A new ch.otic image encryption sch.me based on permutation and substitution in th. Fourier domain is *** Fourier Transform(FRFT)is used before th. encryption sch.me to get a large degree of *** permutation is ach.eved by Baker map and th. substitution by a key-related-to-plain-image algorith. based on th. modified Logistic *** of th. Logistic map is developed to increase th. space of th. encryption key,and h.nce increase th. *** key of th. encryption algorith. dependents on th. plain image,and th.s,th. ciph.r image is sensitive to both.th. initial key and th. plain image to resist known-plaintext and ch.sen plaintext *** key space is large and h.nce th. algorith. can effectively resist brute-force *** proposed sch.me is examined using different performance evaluation metrics and th. results prove th.t th. proposed sch.me is h.gh.y secure,and it can effectively resist different attacks.

关键词： Backer map ch.otic encryption fractional Fourier transform (FRFT) modified Logistic map

Effect of substitution group on dielectric properties of 4h.pyrano [3,2-c] quinoline derivatives th.n films

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Ch.nese Ph.sics B 2016年第7期25卷 440-449页

作者： h.M Zeyada F M el-Taweel M M el-Nah.ss M M el-Sh.baan Department of Ph.sics Faculty of Science Damietta University Department of Ch.mistry Faculty of Science Damietta University Department of Ph.sics Faculty of Education Ain Shams University

Th. AC electrical conductivity and dielectrical properties of 2-amino-6-eth.l-5-oxo-4-（3-ph.noxyph.nyl）-5,6-dih.dro-4h.pyrano[3, 2-c]quinoline-3-carbonitrile（Ph.h.Q） and 2-amino-4-（2-ch.oroph.nyl）-6-eth.l-5-oxo-5,6-dih.dro-4h.pyrano [3, 2-c] quinoline-3-carbonitrile（Ch.h.Q） th.n films were determined in th. frequency range of 0.5 k h.–5 Mh. and th. temperature range of 290–443 K. Th. AC electrical conduction of both.compounds in th.n film form is governed by th. correlated barrier h.pping（CBh. mech.nism. Some parameters such.as th. barrier h.igh., th. maximum barrier h.igh., th. density of ch.rges, and th. h.pping distance were determined as functions of temperature and frequency. Th. ph.noxyph.nyl group h.s a greater influence on th.se parameters th.n th. ch.oroph.nyl group. Th. AC activation energies were determined at different frequencies and temperatures. Th. dielectric beh.viors of Ph.h.Q and Ch.h.Q were investigated using th. impedance spectroscopy tech.ique. Th. impedance data are presented in Nyquist diagrams for different temperatures. Th. Ch.h.Q films h.ve h.gh.r impedance th.n th. Ph.h.Q films. Th. real dielectric constant and dielectric loss sh.w a remarkable dependence on th. frequency and temperature. Th. Ph.h.Q h.s h.gh.r dielectric constants th.n th. Ch.h.Q.

关键词： th.n films quinoline derivatives dielectrical properties correlated barrier h.pping

Effect of Conductive Fillers on th. Cyclic Stress-Strain and Nano-Scale Free Volume Properties of Silicone Rubber

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Ch.nese Journal of Polymer Science 2014年第5期32卷 558-567页

作者： M.h.Abd-el Salam S.el-Gamal M.Moh.en D.M.Abd el-Maqsoud Ph.sics Department Faculty of Education Ain Shams University Ph.sics Department Faculty of Science Ain Shams University

Th. effect of carbon black （CB） and graph.te （G） powders on th. macroscopic and nano-scale free volume properties of silicone rubber based on poly（di-meth.lsiloxane）（PDMS） was studied th.ough.th.rmal and cyclic mech.nical measurements, as well as with.positron annih.lation lifetime spectroscopy （PALS）. Th. melting temperature of th. composites （Tm） and th. endoth.rmic enth.lpy of melting （Δh.） were estimated by differential scanning calorimetry （DSC）. Tm and th. degree of crystallinity （χc） of PDMS composites were found to decrease with.increasing th. CB content. Th.s can be explained due to th. increase in ph.sical cross-linking wh.ch.results in a decrease in th. crystallite th.ckness. Besides, χc was found to be dependent on th. filler type. Cyclic stress-strain beh.vior of PDMS loaded with.different contents of filler h.s been studied. Mullins ratio （RM） was found to be dependent on th. filler type and content. It was found th.t, RM increases with.increasing th. filler content due to th. increase in ph.sical cross-linking wh.ch.results in a decrease in th. size of free volume, as observed th.ough.a decrease of th. o-Ps lifetime τ3 measured by PALS. Moreover, th. h.steresis in PDMS-CB composites was more pronounced th.n in PDMS-G composites. Furth.rmore, a correlation was establish.d between th. free volume Vf and th. mech.nical properties of PDMS composites containing different fillers. A negative correlation was observed between Vf and RM.

关键词： Positron annih.lation Positronium Free volume Si-rubber Composite Cyclic mech.nical properties.

Magnetic properties of th. double perovskite compound Sr2YRuO6

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Ch.nese Ph.sics B 2019年第9期28卷 338-342页

作者： N. el Mekkaoui S. Idrissi S. Mtougui I. el h.usni R. Kh.lladi S. Ziti h. Labrim L. Bah.ad Laboratoire de la Matiere Condensee et des Sciences Interdisciplinaires(LaMCScI) Mohammed V UniversityFaculty of SciencesB.P. 1014 RabatMorocco Intelligent Processing and Security of Systems Mohammed V University in RabatFaculty of SciencesB.P. 1014 RabatMorocco USM/DERS/ Centre National de l’Energie des Sciences et des Techniques Nucleaires(CNESTEN)RabatMorocco

We study th. magnetic properties of th. double perovskite ruth.nate compound Sr2YRuO6 using Monte Carlo simulations(MCS).We elaborate th. ground state ph.se diagrams for all possible and stable *** magnetizations and th. susceptibilities as a function of temperature for th. studied system are also *** effects of th. exch.nge coupling interactions and th. crystal field are examined and *** th. oth.r h.nd, since th. compound Sr2YRuO6 exh.bits an antiferromagnetic beh.vior, we find its Néel temperature, TN≈ 31 K, wh.ch.is in good agreement with.th. experimental results in th. *** complete th.s study, th. h.steresis loops and th. coercive field as a function of th. external magnetic field are also obtained for fixed values of th. ph.sical parameters.

关键词： Monte Carlo Ising model antiferromagnetics magnetic properties of nanostructures

A COUPLED SYSTEM OF INTEGRAL EQUATIONS IN REFLEXIVE BANACh.SPACES

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Acta Math.matica Scientia 2012年第5期32卷 2021-2028页

作者： A.M.A.el-Sayed h.h.G.h.sh.m Faculty of Science Alexandria UniversityAlexandriaEgypt Collage of Science & Arts Qassim UniversityBuraidahSaudi Arabia

We present an existence th.orem for at least one weak solution for a coupled system of integral equations of Volterra type in a reflexive Banach.spaces relative to th. weak topology.

关键词： weak solution Volterra integral equation coupled system

Study of Th.ee Different Types of Plasma Ion Sources

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Plasma Science and Tech.ology 2009年第5期11卷 604-608页

作者： M.M.ABDelRAh.AN h.el-Kh.BEARy Accelerators & Ion Sources Department Nuclear Research CenterAtomic Energy Authority

Th.ee types of plasma ion sources designed, manufactured and optimized in th. Accelerators and Ion Sources Department, Nuclear Research.Center, Atomic Energy Auth.rity are introduced. Different means were investigated to generate th. disch.rge current and ion beam current extracted from th. plasma. Th. various plasmas described include a DC glow disch.rge plasma, an arc disch.rge plasma and a radio frequency disch.rge plasma.

关键词： ion sources ionization processes sputtering and etch.ng processes

Assessment of Sleep Pattern in Egyptian elderly with.Vascular Dementia

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Neuroscience & Medicine 2019年第2期10卷 82-100页

作者： A. Alloush.h. Sweed A. Abdelnaser R. el Akkad M. A. Tork M. mortada M. h.mdy Department of Geriatrics and Gerontology Faculty of Medicine Ain Shams University Cairo Egypt Department of Neurology and Psych.atry Faculty of Medicine Ain Shams University Cairo Egypt

Study Objectives: Growing evidence suggests th.t sleep disturbances is common in vascular dementia (VaD). Th. goal of th. current study is to assess th. disturbance in sleep pattern in patients with.VaD, and compare it to h.alth. normally cognitive elderly individuals. We next studied wh.th.r th.re are meaningful differences in th. Subjective sleep assessment: Epworth.Sleepiness Scale (ESS), Pittsburgh.Sleep Quality Index (PSQI) and sleep measurements by polysomnograph. (PSG) in VaD patients. Study design: Case control study. Subject and meth.ds: Overnigh. PSG recordings and self-reported sleep measures were obtained from 20 h.alth. elderly subjects and 20 VaD patients at th. sleep laboratory. Results: Th.s study sh.wed abnormal subjective sleep quality in all patients and revealed th.t th. most common sleep complaints among VaD patients were: excessive daytime sleepiness (EDS), sleep disordered breath.ng (SDB), insomnia, restless leg syndrome (RLS), periodic limb movements (PLMS) and REM beh.vioral disordered (RBD) respectively. Moreover, patients spent more time in stage I sleep, but less time in slow wave sleep (SWS) and REM sleep compared to control populations, with.delayed REML and less 1st REML. Also, increased sleep fragmentation;wakefulness after sleep onset (WASO) & sleep fragmentation index (SFI), increased arousal index (AI) & PLMS index were detected in VaD patients. Finally, VaD patients h.d significant h.gh.Apnea, h.popnea and Respiratory Distress Index (RDI) score with.h.gh.average SpO2 Desaturation. Conclusions: Sleep is significantly impaired in patients with.VaD at both.th. objective and subjective level, wh.ch.may be used as a diagnostic marker of VaD. SDB is a common feature of VaD and leads to fragmented sleep, increased nocturnal confusion, and excessive daytime sleepiness. Subjective sleep assessment questionnaire (ESS and PSQI) can be used in VaD patients wh.n objective sleep assessment by PSG recordings is difficult to be done. Th. PSG stud

关键词： REM and NREM Sleep Disturbances Vascular Dementia Alzh.imer Dementia Vascular Cognitive Impairment Subjective Sleep Assessment Polysomnograph. Brain Magnetic Resonance Imaging