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A comparative study of liquid and solid inner contact roxatidine acetate ion-selective electrode membranes

Chinese Chemical Letters 2015年第6期26卷 714-720页

作者： mohamed K.abd el-Rahman Hala E.Zaazaa samah s.Abbas Badr el-Zeany Zeinab A.el-sherif Dalia A.el-Haddad Analytical Chemistry Department Faculty of PharmacyCairo University National Organization for Drug Control and Research

A comparative study was conducted using two designs of a roxatidine acetate （ROX）-selective electrode; a conventional liquid inner contact called electrode A and a graphite-coated solid contact called electrode 13. The fabrication of electrodes was based on roxatidine-tetraphenylborate （ROX-TPB） as an ion-association complex in a PVC matrix using different plasticizers. electrode A has a linear dynamic range of 2.2 ×10^-5 mol/L to 1.0 ×10^-2 mol/L, with a Nernstian slope of 54.7 mV/decade and a detection limit of 1.4 ×10^-6 mol/L. electrode B shows linearity over the concentration range of 1.0×10^-6 mol/L to 1.0×10^-2 tool/L, with a Nernstian slope of 51.2 mV/decade and a limit of detection of 1.1×10^7 mol/L which is remarkably improved as a result of diminishing ion fluxes in this solid contact, ion-selective electrode. The proposed sensors display useful analytical characteristics for the determination of ROX in bulk powder and its pharmaceutical formulation. The present electrodes show clear discrimination of ROX from several inorganic, organic ions, sugars, some common drug excipients and the degradation product （3-[3-（1-piperidinyl methyl） phenoxy] propyl amine） of ROX. Furthermore, the proposed electrodes were utilized for the determination of ROX in human plasma, where electrode B covers drug Cmax which indicated its applicability to pharmacokinetic, bioavailability and bioequivalent studies. The results obtained by the proposed electrodes were statistically analyzed and compared with those obtained by a reported HPLC method. No significant difference for either accuracy or precision was observed.

关键词： Comparative study Roxatidine acetate Liquid inner contact electrode solid contact electrode Degradation product Plasma

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Design and Analysis of an OsA-BR MAC Protocol for Cognitive Radio Ad Hoc Networks

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International Journal of Communications, Network and system sciences 2014年第7期7卷 223-234页

作者： Hassan Al-Mahdi mohamed wahed safa abd el-Aziz Faculty of sciences and Arts Al Jouf UniversityAl QuryyatKSA Faculty of Computers and Information Suez Canal UniversityIsmailiaEgypt

Cognitive Radio (CR) is a new communication network paradigm introduced to solve the problems of spectrum scarcity and inefficient spectrum usage. Basically, it allows the secondary Users (sUs) to utilize the Licensed Channels (LCs) of the Primary Users (PUs) in an opportunistic manner without causing any harmful interference to the PUs. However, there are many challenges associated with cognitive radio networks, such as the CR Medium Access Control (CR-MAC) protocols. An important issue for CR-MAC protocols is to identify whether the spectrum is licensed or unlicensed. In addition, the sudden appearance of the PU is the most important feature of the distributed CR-MAC protocols. In this paper, a multichannel CR-MAC protocol, which reacts efficiently to the appearance of the PUs, is developed. The proposed protocol is named Opportunistic spectrum Access with backup channel and Buffered data with Resume (OsA-BR). The OsA-BR is an unaided rendezvous, asynchronous, and contention-based MAC protocol. The proposed protocol operates in heterogeneous environment, where the sUs utilize both LCs and unlicensed channel (ULs) and the activities of the Classical Users (CUs) are taken into consideration. In addition, the concept of the backup channel and the buffer with resume are introduced. The simulation results show that OsA-BR accomplishes 35% throughput gain over the sWITCH protocol and 55% over other CR-MAC protocols.

关键词： Rendezvous Cognitive Radio Ad Hoc Analytical Model

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Cu(Ⅱ),Ni(Ⅱ),Co(Ⅱ),Mn(Ⅱ),Zn(Ⅱ)和Cd(Ⅱ)的乙基3-(2-氨硫化亚肼基)-2-(羟胺基)丁烯酸酯配合物:合成、表征和细胞毒性(英文)

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无机化学学报 2014年第6期30卷 1435-1450页

作者： Ramadan M el Bahnasawy abdou s el-Tabl Mohamad M E shakdofa Noran M abd el-wahed Chemistry Department Faculty of ScienceMenoufia University Chemistry Department Faculty of Science and ArtsKhulaisKing Abdulaziz University Inorganic Chemistry Department National Research Center

合成了Cu（Ⅱ）,Ni（Ⅱ）,Co（Ⅱ）,Mn（Ⅱ）,Zn（Ⅱ）和Cd（Ⅱ）的乙基3-（2-氨硫化亚肼基）-2-（羟胺基）丁烯酸酯配合物（H2L）并用元素分析,DTA热分析,IR,UV-Vis,1H-NMR,质谱,顺磁共振以及磁矩,电导率测量等对合成的配合物进行表征... 详细信息

合成了Cu（Ⅱ）,Ni（Ⅱ）,Co（Ⅱ）,Mn（Ⅱ）,Zn（Ⅱ）和Cd（Ⅱ）的乙基3-（2-氨硫化亚肼基）-2-（羟胺基）丁烯酸酯配合物（H2L）并用元素分析,DTA热分析,IR,UV-Vis,1H-NMR,质谱,顺磁共振以及磁矩,电导率测量等对合成的配合物进行表征.摩尔电导率测量结果证明合成的配合物为非电解质.光谱数据表明配体分别表现为一元的三齿配体,一元的二齿配体,中性的二齿配体,中性的三齿配体,一元的四齿配体或二元的四齿配体通过席夫碱的氮原子,氨基硫脲中的氮原子,肟中的氮原子和硫酮中的硫原子与金属离子键合生成围绕金属离子的四面体或平面正方形构型.固态Cu（Ⅱ）（2）,（3）,（4）和（5）的配合物顺磁共振谱表明其为轴向对称,但（10～15）的配合物却为各向异性.配体和配合物（2）,（3）,（10）,（13）,（16）和（19）由于它们对乳腺癌（MCF-7细胞系）和肝癌（HePG-2细胞系）的抑制作用而表现出潜在的抗癌活性.

关键词：缩氨基硫脲肟配合物光谱研究磁性细胞毒性

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Improved RC6 Block Cipher Based on Data Dependent Rotations

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Computers, Materials & Continua 2022年第1期70卷 1921-1934页

作者： Osama s.Faragallah Ibrahim F.elashry Ahmed AlGhamdi Walid el-shafai s.el-Rabaie Fathi E.abd el-samie Hala s.el-sayed mohamed A.elaskily Department of Information Technology College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of electrical Communications Faculty of EngineeringKafrelsheikh UniversityKafrelsheikhEgypt Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of electronics and electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Department of electrical Engineering Faculty of EngineeringMenoufia UniversityShebin El-Kom32511Egypt Department of Informatics Electronic Research Institute(ERI)CairoEgypt

This paper introduces an Improved RC6(IRC6)cipher for data encryption based on data-dependent *** proposed scheme is designed with the potential of meeting the needs of the Advanced Encryption standard(AEs).Four parameters are used to characterize the proposed *** parameters are the size of the word(w)in bits,the number of rounds(r),the length of the secret key(b)in bytes,and the size of the block(L)in *** main feature of IRC6 is the variable number of working registers instead of just four registers as in RC6,resulting in a variable block size for plaintext and *** IRC6 cipher is designed to improve the robustness against attacks by increasing the diffusion for each round and providing greater security with fewer *** effectiveness of the proposed IRC6 scheme is verified against theoretical *** proposed IRC6 scheme depends on full diffusion and confusion mechanisms regardless of the utilized block *** proposed IRC6 scheme saves 70%of the encryption time and 64%of the decryption time of *** simulation results prove that the IRC6 achieves a better encryption/decryption time compared to the ***,the proposed IRC6 is anticipated to fulfill the market needs and system security requirements.

关键词： Cryptography block cipher RC6,IRC6,AEs

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The vitreomacular interface in different types of agerelated macular degeneration

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International Journal of Ophthalmology(English edition) 2017年第2期10卷 246-253页

作者： mohamed abd elM onaem el-Hifnawy Hisham Ali Ibrahim Amir Ramadan Gomaa mohamed A elmasry Ophthalmology Department Alexandria University Faculty of MedicineKhartoum SquareAzaritaAlexandria 21526Egypt

AIM： To evaluate the vitreomacular interface in cases with wet age-related macular degeneration（AMD） and to compare them to eyes with dry AMD and normal ***： This was a cross-sectional comparative study that included 87 eyes with wet AMD,42 eyes with dry AMD and 40 eyes without AMD as a control *** coherence tomography（OCT） examination was performed for all patients to assess the vitreomacular ***： In the wet AMD group,34.5% of cases had vitreomacular adhesion（VMA）.Only 14.3% of dry AMD cases and 10% of control cases had *** was a significant difference between the control group and the wet AMD group（P=0.004） as well as the dry and wet AMD group（P=0.017）.There was also a significant difference between the incidence of VMA in patients with subretinal choroidal neovascularization（CNV,type 1） and intraretinal CNV（type 2 or type 3）（P=0.020）.CONCLUsION： There is an association between posterior vitreous attachment and *** is also an increased incidence of VMA with intra-retinal CNV.

关键词： age-related macular degeneration vitreomacular interface optical coherence tomography macula

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3D FEM simulations and experimental validation of plastic deformation of pure aluminum deformed by ECAP and combination of ECAP and direct extrusion

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Transactions of Nonferrous Metals society of China 2017年第6期27卷 1338-1352页

作者： mohamed Ibrahim abd el AAL Mechanical engineering Department College of Engineering Prince Sattam Bin Abdulaziz UniversityWadi Addawasir Kingdom of Saudi Arabia Mechanical Design & Production Department Faculty of Engineering Zagazig University Zagazig Egypt

Rigid-viscoplastic3D finite element simulations(3D FEM)of the equal channel angular pressing(ECAP),thecombination of ECAP+extrusion with different extrusion ratios,and direct extrusion of pure aluminum were performed ***3D FEM simulations were carried out to investigate the load-displacement behavior,the plastic deformationcharacteristics and the effective plastic strain homogeneity of Al-1080deformed by different forming *** simulationresults were validated by microstructure observations,microhardness distribution maps and the correlation between the effectiveplastic strain and the microhardness ***3D FEM simulations were performed successfully with a good agreement with theexperimental *** load-displacement curves and the peak load values of the3D FEM simulations and the experimentalresults were close from each *** microhardness distribution maps were in a good conformity with the effective plastic straincontours and verifying the3D FEM simulations *** ECAP workpiece has a higher degree of deformation homogeneity thanthe other deformation *** microhardness values were calculated based on the average effective plastic *** microhardness values fitted the experimental results *** microstructure observations in the longitudinal andtransverse directions support the3D FEM effective plastic strain and microhardness distributions result in different formingprocesses.

关键词： equal channel angular pressing (ECAP) extrusion finite element method (FEM) microhardness deformation homogeneity microstructure

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Physio-biochemical and nutrient constituents of peanut plants under bentazone herbicide for broad-leaved weed control and water regimes in dry land areas

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Journal of Arid Land 2020年第4期12卷 630-639页

作者： Hani s sAUDY Ibrahim M el–METWALLY Goma A abd el–sAMAD Agronomy Department Faculty of AgricultureAin Shams University68–Hadayek Shoubra 11241CairoEgypt Botany Departments National Research CentreEl–Behos St.Dokki 12622CairoEgypt

The abundance of broad-leaved weeds in peanut fields represents the handicap in weed management programs, since limited specific herbicides can be recommended to control them. Moreover, the physio-biochemical constituents and nutritional status in peanut plants as affected by available herbicides, i.e., bentazone under water stress conditions are not well known. Therefore, field trials were conducted during the growing seasons in 2016 and 2017 to investigate the interactional impact of irrigation levels(I_(50), I_(75) and I_(100), representing irrigation by 50%, 75% and 100% of crop evapotranspiration, respectively) and weed control practices(bentazone, bentazone+hoeing once, hoeing twice and weedy check as control) on dominant broad-leaved weeds as well as peanut physiological and agronomic traits. Result indicated that the efficiency of weed control for each weeded treatment under I_(50) significantly equaled with its counterpart under I_(75) or I_(100). Bentazone+hoeing once diminished weed biomass by 89.3% and enhanced chlorophyll content of peanut plants by 51.2%. Bentazone relatively caused a reduction in carotenoides. Hoeing twice and bentazone+hoeing once under I_(100) in both growing seasons as well as hoeing twice under I_(75) in 2017 were the superior combinations for boosting pod yield of peanut plants. Treatment of bentazone+hoeing once and I_(75) recorded the lowest reduction in N utilization percentage and the highest increase in potassium utilization percentage of peanut plants. eliminating weeds enhanced water use efficiency by 37.8%, 49.6% and 34.7% under I_(50), I_(75) and I_(100), respectively. In conclusion, peanut seems to be tolerant to bentazone at moderate water supply, thus it can be safely used in controlling the associated broad-leaved weeds.

关键词： biochemical traits drought nutritional status peanut productivity weed growth

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Effect of Cyclic stress Reduction on the Creep Characteristics of AZ91 Magnesium Alloy

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Acta Metallurgica sinica(English Letters) 2015年第8期28卷 1065-1073页

作者： Alaa Farag abd el-Rehim Physics Department Faculty of Science King Khalid University Physics Department Faculty of Education Ain Shams University

The creep deformation behavior of aged AZ91 magnesium alloy under the cyclic stress reduction has been investigated in the temperature range 353–383 K. The microstructural evolution of the AZ91 magnesium alloy at different heat treatment conditions has been studied using optical microscopy and scanning electron microscopy. The minimum strain rate, e_min, was found to be higher under cyclic stress reduction condition than that under static creep condition for the same maximum stress. Cyclic creep acceleration is interpreted using the interaction of moving dislocations with the existing b-phase（Mg17Al12） precipitates. The mean value of the activation energy of secondary creep stage was found to be equal to that quoted for lattice self-diffusion of magnesium mechanism.

关键词： Magnesium alloys Microstructure Cyclic stress Dislocations

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serum ferritin in neonatal cholestasis: A specific and active molecule or a non-specific bystander marker?

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Hepatobiliary & Pancreatic Diseases International 2019年第2期18卷 173-180页

作者： Behairy el-sayed Behairy Hatem abd-Alsattar Konswa Hanaa Talaat Ahmed Dina shehata el-Azab Nermin mohamed Adawy Ahmad mohamed sira Department of Pediatric Hepatology Gastroenterology and Nutrition National Liver Institute Menofiya University Department of Pathology National Liver Institute Menofiya University

Background: serum ferritin(sF) and consequently hepatic iron have long been considered important in liver fibrosis progression. They have been studied in different liver diseases with no previous reports in neonatal cholestasis(NC). This study aimed to measure sF in different etiologies of NC and investigate its relation to hepatic iron and fibrosis. Methods: sF was measured in 75 infants, including 50 with NC and 25 with sepsis. sF was compared between these two groups. Biochemical parameters, hepatic iron grades, and liver fibrosis and other histopathological characteristics and correlated with sF were assessed in NC group. Finally, a comparison between intrahepatic cholestasis and obstructive etiology was performed. Results: sF was elevated in NC(1598 ± 2405 ng/mL) with no significant difference from those with sepsis( P = 0.445). NC and sepsis constituted augmenting factors leading to more elevation of sF(2589 ± 3511 ng/mL). sF was significantly correlated with hepatic iron grades( r = 0.536, P s( ≥ grade 3) of iron deposition with sensitivity of 100%, specificity of 70% and accuracy of 85%. Moreover, sF was significantly higher( P se with intrahepatic cholestasis(2602 ± 3154 ng/mL) and their prevalent pathological findings of giant cell transformation( P = 0.009) and hepatocyte swelling( P = 0.023) than those with obstructive etiology(672 ± 566 ng/mL) and their prevalent pathological findings of ductular proliferation( P = 0.003) and bile plugs( P = 0.002). sF was unrelated to the grade of liver fibrosis( P = 0.058). Conclusions: sF is non-specifically elevated in NC, with positive correlation to hepatic iron grades. sF ≥ 803.5 ng/mL can predict higher grades( ≥ grade 3) of hepatic iron. However, an active role of increased sF and hepatic iron in disease progression remains questionable.

关键词： Biliary atresia Liver fibrosis Hepatic iron grade Intrahepatic cholestasis Iron

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Facies Analysis and Biostratigraphy of the Miocene sequence,Cairo-suez District,Egypt

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Journal of Earth science 2017年第1期28卷 1-8页

作者： abdelbaset el-sorogy mohamed abd-elmoneim Ahmed Mowafi Khaled Al-Kahtany Hisham Gahlan Department of Geology and Geophysics College of Science King Saud University Riyadh 11451 Saudi Arabia Geology Department Faculty of Science Zagazig University Zagazig 44519 Egypt

Miocene siliciclastic-carbonate deposits are widely exposed in Cairo-suez District, Egypt. These deposits are underlain and overlain by continental sediments of Oligocene and post Miocene, respectively. Three stratigraphic sections were investigated at Gabals Geneife, Homeira and Gharra. Lithostrtigraphically, the Miocene sequence could be differentiated into two main rock units representing shallow deposits with relatively intermittent deep marine incursions. These are from base to top, Gharra Formation and Genefe Formation. Detailed macrofossils investigations led to the recognition of four macrofossil zones, namely Alectryonella plicatula-Crassostrea frondosa Range Zone, Echinolampas amplus-scutella ammonis Range Zone, Chlamys（Macrochlamys） sardoa-Chlamys（Argopecten） submalvinae Range Zone, and Chlamys gentoni-Pecten（Oppenheimopecten） benedictus-Pecten（P.） ziziniae Assemblage Zone. Microfacies analysis and identified taxa indicated that the Miocene sequence was deposited in transgressive-regressive cycles ranged from near shore, warm shallow inner to middle shelf marine environments with storm influence during the accumulation of the oyster banks.

关键词： facies analysis biostratigraphy Miocene Cairo-suez District Egypt.

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