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Survey of Clustering Schemes in Mobile Ad hoc Networks

Communications and Network 2013年第2期5卷 8-14页

作者： Abdelhak Bentaleb Abdelhak Boubetra saad Harous Department of Computer Science University of Bachir el Ibrahimi Bordj Bou Arreridj Algeria Faculty of Information Technology United Arab Emirates University P.O Box 17551 Al Ain UAE

Mobile ad-hoc networks (MANETs) are a specific kind of wireless networks that can be quickly deployed without pre- existing infrastructures. They are used in different contexts such as collaborative, medical, military or embedded applications. However, MANETs raise new challenges when they are used in large scale network that contain a large number of nodes. Subsequently, many clustering algorithms have emerged. In fact, these clustering algorithms allow the structuring of the network into groups of entities called clusters creating a hierarchical structure. Each cluster contains a particular node called cluster head elected as cluster head according to a specific metric or a combination of metrics such as identity, degree, mobility, weight, density, etc. MANETs has drawbacks due to both the characteristics of the transmission medium (transmission medium sharing, low bandwidth, etc.) and the routing protocols (information diffusion, path finding, etc.). Clustering in mobile ad hoc networks plays a vital role in improving resource management and network performance (routing delay, bandwidth consumption and throughput). In this paper, we present a study and analyze of some existing clustering approaches for MANETs that recently appeared in literature, which we classify as: Identifier Neighbor based clustering, Topology based clustering, Mobility based clustering, Energy based clustering, and Weight based clustering. We also include clustering definition, review existing clustering approaches, evaluate their performance and cost, discuss their advantages, disadvantages, features and suggest a best clustering approach.

关键词： Clustering Mobile Ad hoc Networks Routing Protocol

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A smart simple spectrophotometric method for simultaneous determination of binary mixtures

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Journal of Pharmaceutical Analysis 2012年第5期2卷 382-385页

作者： Eman S.elzanfaly Ahmed S.saad Abd elaziz B.Abd elaleem Analytical Chemistry Department Faculty of PharmacyCairo UniversityKasr-El Aini Street11562 CairoEgypt

A new simple spectrophotometric method was developed for the simultaneous determination of drugs with interfering spectra in binary mixtures without previous separation. The new method is based on a simple modification for the ratio subtraction method. This modification enabled wider range of application. The proposed ratio difference method was applied for the determination of brimonidine and timolol in laboratory prepared mixtures with mean percentage recoveries 100.40±2.29 and 101.23± 1.30 respectively, and in their pharmaceutical formulation with mean percentage recoveries 101.08±0.44 and 100.66±0.52 respectively. The suggested ratio difference method was validated according to USP guidelines and can be applied for routine aualitv control testing.

关键词： Spectrophotometry Ratio difference Binary mixtures Brimonidine Timolol

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Biosynthesis of raw starch degradingβ-cyclodextrin glycosyltransferase by immobilized cells of Bacillus licheniformis using potato wastewater

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BIOCelL 2021年第6期45卷 1661-1672页

作者： YASSER S.MOSTAFA saad A.ALAMRI SULIMAN A.ALRUMMAN TAREK H.TAHA MOHAMED HASHEM MAHMOUD MOUSTAFA LAMIAA I.FAHMY Department of Biology College of ScienceKing Khalid UniversityAbha9004Saudi Arabia Prince Sultan Bin Abdulaziz Center for Environmental and Tourism Research and Studies King Khalid UniversityAbha9004Saudi Arabia Environmental Biotechnology Department Genetic Engineering and Biotechnology Research InstituteCity of Scientific Research&Technological ApplicationsNew Borg El-Arab City21934Egypt Department of Botany and Microbiology Faculty of ScienceAssiut UniversityAssiut71515Egypt Department of Botany and Microbiology Faculty of ScienceSouth Valley UniversityQena83523Egypt Department of Microbiology and Immunology Faculty of PharmacyOctober University for Modern Science and ArtGiza12451Egypta

The study was sought to enhance the synthesis of thermal stableβ-cyclodextrin glycosyltransferase(β-CGTase)using potato wastewater as a low-cost medium and assess the degree to which it is efficient for industrial production ofβ-cyclodextrin(β-CD)from raw potato *** bacteria producingβ-CGTase was isolated from Saudi Arabia and the promising strain was identified as Bacillus licheniformis using phylogenetic analysis of the 16S rRNA ***-encapsulated cultures exhibited twice-fold ofβ-CGTase production more than free *** electron microscopy(SEM)of polymeric capsules indicated the potential for a longer shelf-life,which promotes the restoration of activity in bacterial cells across semi-continuous fermentation ofβ-CGTase production for 252 *** optimal conditions forβ-CGTase synthesis using potato wastewater medium were at 36 h,pH of 8.0,and 50°C with 0.4%potato starch and 0.6%yeast extract as carbon and nitrogen sources,*** purified enzyme showed a specific activity of 63.90 U/mg with a molecular weight of∼84.6 kDa as determined by SDS-PAGE *** high enzyme activity was observed up to 60°C,and complete stability was achieved at 75°*** levels of activity and stability were shown at pH 8.0,and the pH range from 7.0–10.0,*** enzyme has an appreciable affinity for raw potato starch with a Km of 5.7×10−6 M and a Vmax of 87.71μmoL/mL/min.β-CD production was effective against 25 U/g of raw potato *** outcomes demonstrated its feasibility to develop a fermentation process by integrating the cost-effective production ofβ-CGTase having distinctive properties forβ-CD production with ecofriendly utilization of potato wastewater.

关键词： Potato wastewater Bacillus licheniformis β-CGTase 16S rDNA gene Semi-continuous fermentation β-cyclodextrin

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Effectiveness of Three Bio-Rational Products and a Traditional Insecticide against Thripsspp. and Bemisia tabaciAttacking Tomato Fields in Kafr el-Sheik Governorate, Egypt

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Agricultural Sciences 2018年第12期9卷 1538-1552页

作者： Hala Adel saad A. Gaffar Ahmed Toman Central Laboratory for Organic Agriculture Agricultural Research Center Cairo Egypt Plant Protection Research Institute Agricultural Research Center Cairo Egypt

Destructive effects of conventional insecticides on environment have created a necessity to introduce bio-rational products in pest control programs. Effectiveness of bio-pesticide (Beauvaria bassiana), natural oil (anti-insect), a botanical extract (nimbecidine) and malathion insecticide was evaluated against Thrips spp. and Bemisia tabaci attacking tomato in Kafr el Sheik, Egypt. The trial was conducted during two successive seasons;2017-18 in a total area of 4912 m2 cultivated with tomato cultivar zero 42. The experiment was set up in a randomized complete block design with five replications for each treatment. Yellow sticky traps were used to monitor population of both pests before and after spraying, in addition, their numbers on plants were counted. Results revealed that highest control rates of both pests were recorded after the fourth day of each spraying. Long inter-applications periods decreased effectiveness and the greatest control resulted when three consecutive sprayings were applied. Malathion achieved the highest suppression of both pests. Within the bio-rational pesticides, nimbecidine gave the greatest thrips control whereas products showed no significant difference for whiteflies. The study recommends those bio-rational compounds to join Integrated Pest Management programs of both pests in Egypt, taking into consideration spraying for 3 consecutive times with at least 5 days intervals.

关键词： Solanum lycopercicum Bio-Pesticide Natural Oil Nimbecidine Malathion

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Cervical Length Estimation and Cervicovaginal Fluid for Placental α-Microglobulin 1 Testing to Screen Women Had Threatened Preterm Labor for Time till Spontaneous Labor

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Advances in Reproductive Sciences 2020年第1期8卷 57-70页

作者： Mohamed Kandil Abdelhaseib Salah saad Alaa Masood Departments of Obstetrics & Gynecology Faculty of Medicine Menoufia University Shibin El Kom Egypt

Objectives: Evaluation of diagnostic performance of rapid testing of cervico-vaginal fluid (CVF) for fetal fibronectin (FFN) and placental α-microglobulin 1 (PAMG-1) as screening of women presented by threatened preterm labor (TPTL) with intact membranes for duration till getting spontaneous labor (SL). Patients & Methods: 37 women presenting with TPTL underwent CVF samplings before digital examination and then underwent transvaginal ultrasonography for estimation of cervical length (CL). All women received fluid and anxiolytic therapy and if uterine contractions persisted, all had received tocolytic therapy with oral nifedipine or intravenous magnesium sulphate according to requirements. Incidence of SL within Results: Incidence of SL was 13.5%, 35.2% and 51.3% within 48-hr, 2 - 7 and 7 - 14 days, respectively. Duration till labor after sampling was positively correlated with CL, while was negatively correlated with positive FFN and PAMG-1 tests. Positive FFN test had high specificity, while positive PAMG-1 test had high sensitivity for labor within 7 days. Regression analysis defined short CL and positive PAMG-1 test as significant predictors for short duration till SL. ROC curve analysis defined short cervix and positive PAMG-1 test as significant predictors for labor within 48-hr and within 2 - 7 days respectively and combined negative PAMG-1 test and CL of 20 - 25 mm were significant predictors for labor within 7 - 14 days. Conclusion: PAMG-1 test had high specificity, if positive, for predicting SL and high NPP, if negative, for excluding labor within 7 days, so it can be used as rapid adjuvant to clinical evaluation to help management decision-making. Moreover, PAMG-1 test is recommended screening test for being easy-to-use bedside test, provides rapid results, can be used after vaginal exam and coitus and does not require a speculum examination or specialized equipment to analyze results.

关键词： Threatened Preterm Labor Cervico-Vaginal Fluid Fetal Fibronectin Placental α-Microglobulin 1 Screening Spontaneous Labor

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A Novel Method for PID Tuning Using a Modified Biogeography-Based Optimization Algorithm

A Novel Method for PID Tuning Using a Modified Biogeography-...

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第24届中国控制与决策会议

作者： M. M. Sayed M. S. saad H. M. Emara E. E. Abou el-Zahab the department of electrical Power and Machines Cairo UniversityEgypt.

Proportional integral derivative （PID） controller tuning is an area of interest for researchers. This paper presents a novel method for PID controller tuning using a modified biogeography-based optimization（MBBO） algorithm. Biogeography-based optimization （BBO） is a novel evolutionary algorithm that is based on the mathematical models of biogeography. Biogeography is the study of the geographical distribution of biological organisms. In the BBO model, problem solutions are represented as islands, and the sharing of features between solutions is represented as immigration and emigration between the islands. In this paper, a modified version of the BBO is proposed to improve its convergence. The MBBO algorithm is compared with the BBO using benchmarks functions. The proposed algorithm is applied to the problem of PID controller tuning and is compared with conventional biogeography-based optimization （BBO）, and Particle swarm optimization （PSO）.

关键词： Process Control evolutionary algorithm (EA) Biogeography-Based Optimizationand PID controller

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Temporal and Spatial Effects on Some Physiological Parameters of the Bivalve Lithophaga lithophaga(Linnaeus, 1758) from Coastal Regions of Alexandria, Egypt

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Open Journal of Ecology 2014年第12期4卷 732-743页

作者： Eman Hashem Radwan Sherifa Shaker Hamed Gaber Ahmed saad Department of Zoology Faculty of Science Alexandria University Alexandria Egypt Department of Zoology Faculty of Science Damnhour University El Behara Egypt Department of Zoology College of Science King Saud University Saudi Arabia KSA Department of Biology College of Medicine Dammam University Saudi Arabia KSA

The date clam, Lithophaga lithophaga is a popular edible bivalve. It was collected from three different locations (Abo-Quir, Miami and el-Mex) along the coast of Alexandria-Egypt to determine the effect of two heavy metals as copper (Cu) and cadmium (Cd). The three organs were selected: gill, mantle and digestive gland. The enzymatic change is correlated with the concentration of metals. The present results suggest that Miami water is less polluted with Cu and Cd as compared to the two other locations. The physicochemical parameters are not significant among the three locations. Water of Abu-Quir and el-Max may be hazardous to bivalves. The order of levels of Cu and Cd was: gill > digestive gland > mantle. The present study illustrated that, in Abu Quir, there was a high positive correlation between Cd and Succinate dehydrogenase (SDH) as r = 0.969 whereas Cu and SDH as r = -0.91.

关键词： Lithophaga lithophaga Heavy Metals Cu Enzyme Activities

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Impact of Selected Environmental Pollutants on the Ultrastructure of the Gills in Pinctada radiatafrom Coastal Zones, Egypt

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Open Journal of Ecology 2014年第14期4卷 907-917页

作者： Sherifa Shaker Hamed Eman Hashem Radwan Gaber Ahmed saad Department of Zoology College of Science King Saud University Saudi Arabia KSA Department of Zoology Faculty of Science Alexandria University Alexandria Egypt Department of Zoology Faculty of Science Damnhour University El Behara Egypt Department of Biology College of Medicine Dammam University Saudi Arabia KSA

There has been an increasing interest in marine oysters (order: Petridae) in recent years because their numbers are declining in many parts of the world and also because they are used as monitors of pollution. The present study describes the microscopic structure of gills as viewed by light and electron microscopy in two locations selected in Alexandria coast, Eastern Harbor (E.H.) and el Asafra. The specimens in the E.H. represent the presence of extracellular mineralized granules.

关键词： Gill Bivalve Transmission electron Microscope Pinctada radiata

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Impact of past HBV exposure on virological response to combined interferon ribavirin therapy in patients with chronic HCV genotype 4

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Open Journal of Internal Medicine 2011年第2期1卷 38-43页

作者： M. Said M. S. el-Raziky M. Abdel-Hamid Y. saad M. Hashem S. Zakaria M. K. Mohamed G. Esmat 不详

Aim: is to investigate if past exposure to HBV in chronic HCV infection promotes the progression of liver disease and influences Interferon (INF) response or not. Methods: 185 patients with chronic HCV were recruited and randomized into 2 groups, group I was treated with PEG-IFN alfa-2b plus ribavirin and group II with 3 MU/TIW IFN alfa-2b plus ribavirin. All patients had HBsAg negative & patients had HBc Ab positive tested for HBsAb. Patients with HBc Ab (n = 37) were tested for serum HBV DNA. Pretreatment liver biopsy and Immunohistochemistry was performed for detection of HBsAg and HBcAg using monoclonal antibodies. Demographic and laboratory data were collected. Results: 70/185 (38%) patients had Anti-HBc, 37 (20%) had isolated anti-HBc and none of the 37 subjects with isolated anti-HBc had serum HBV DNA. Sustained Viral Response (SVR) was achieved in 32/70 (46%) and 46/115 (40%) in anti-HBc seropositive and seronegative patients respectively, in conventional IFN group SVR was 37% and 39% in past HBV exposed patients and unexposed respectively, in PEG IFN group SVR was 59% and 41% in past HBV exposed patients and unexposed respectively. Among anti-HBc and anti-HBs seropositive patients SVR was 10/12 [83%] and 4/21 [19%] p = 0.004 in PEG and conventional IFN respectively. Marked fibrosis was diagnosed in 20% past HBV exposed patients versus 10% in unexposed patients (p = 0.01). Conclusion: past HBV exposure promotes the progression of liver disease but has no effect on the SVR to antiviral therapy in chronic HCV genotype 4 patients.

关键词： HCV Genotype 4 Past HBV Exposure Response To Interferon Therapy

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Efficient Facilitated Transport of Lead and Cadmium Across a Plasticized Triacetate Membrane Mediated by D2EHPA and TOPO

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Materials Sciences and Applications 2011年第6期2卷 615-623页

作者： Omar Arous Fairouz saad Saoud Mourad Amara Hacène Kerdjoudj Laboratory of Hydrometallurgy and Inorganic Molecular Chemistry U.S.T.H.B-Faculty of Chemistry POBOX 32 El Alia 16111 Bab Ezzouar Algeria

Cellulose triacetate membranes doped with organo-phosphoric carriers (2-ethylhexyl) phosphoric acid noted (D2EHPA) or trioctyl phosphine oxide noted (TOPO) as fixed carriers and 2-nitro phenyl octyl ether noted (NPOE) or tris ethylhexyl phosphate noted (TEHP) as a plasticizers have been prepared and applied for investigation to the facilitated transport of Pb(II) and Cd(II) ions from aqueous nitrate source phase. The membranes Polymer-Plasticizer- Carrier were characterised using chemical techniques as well as Fourier Transform Infra-Red (FTIR), X-ray Diffraction and Scanning electron microscopy (SEM). A study of the transport across a polymer inclusion membrane has shown that the lead or cadmium transport efficiency was increased using D2EHPA as carrier at pH 1-2.

关键词： Cellulose Triacetate NPOE TEHP D2EHPA TOPO Membrane

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