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Helicobacter pylori and gastric cancer in the middle East: A new enigma?

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World Journal of Gastroenterology 2010年第26期16卷 3226-3234页

作者： Nawfal R hussein Institute of Infection Immunity and Inflammation and the Centre for Biomolecular Sciences University of Nottingham Nottingham NG7 2RD United Kingdom

The middle East is the home of ethnic groups from three main backgrounds: Semitic (Arabs and Jews), Indo-European (Persians and Kurdish) and Turkic (Turkish and Turkmens). Its geographic location, which has been under continuous influences from Asia, Europe and Africa, has made it an ideal site for epidemiological studies on Helicobacter pylori (H. pylori) infection and genotyping. The gastric cancer rate differs in this region from very high in Iran (26.1/105) to low in Israel (12.5/105) and very low in Egypt (3.4/105). Epidemiological studies showed that the prevalence of H. pylori is almost similar in those countries with a high level of infection in childhood. Importantly, the frequency of vacA s1 and m1 regions and cagA+ genotypes were higher in non Semitic populations who inhabit the North than Semitic populations, the inhabitants of Southern parts of the middle East. H. pylori infection prevalence, distribution pattern of virulence factors, diet and smoking could not have explained the difference in cancer rate. This reflects the multifactorial aetiology of gastric cancer and suggests that H. pylori infection does not always directly correlate with the risk for gastrointestinal disease, such as gastric cancer. Further detailed investigations and international comparative studies of each risk factor needto be performed to investigate whether this represents a true enigma.

关键词： Helicobacter pylori middle East Gastric cancer dupA cagA vacA iceA

Gamma-ray measurements of natural radioactivity in sedimentary rocks from Egypt

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Nuclear Science and Techniques 2006年第2期17卷 123-128页

作者： A.m.EL-ARABI Adel G.E.ABBADY A.S.hussein Physics Department Faculty of Science South Valley University Qena Egypt Radiation Protection Department Nuclear Power Plants Authority Egypt

The aim of this study was to measure concentrations and distributions of natural radionuclides occurring in rocks. The activity concentrations (Bq·kg-1) of the naturally occurring radionuclides 226Ra, 232Th, and 40K in sedi- mentary rock samples from Eastern Desert (Um El-Huetat), Nile Valley (Gebel Owina) and from southwest Sinai (Wadi Ghweiba) were measured using a high-purity germanium detector. The samples under investigation (clay, shale and sandstone) were used as raw materials in the construction industry (bricks, ceramics, cement, fillers, etc.). Though the sediments of Egypt have already been investigated in the geological and mineralogical aspects, it is necessary to investigate the natural radioactivity in order to complete their classification. The average concentration values of 226Ra, 232Th, 40K in the surveyed samples were 47 ± 7 , 21± 5, 393±19 ***-1 (clay); 23 ± 5, 30 ± 6, 563 ± 24 ***-1 (shale); and 17 ± 4, 14 ± 4, 299 ± 17 ***-1 (sandstone), respectively. All sediment samples have radium equivalent activities ranging from 55 to 115 Bq·kg-1, lower than the limit set in the OECD Report (370 Bq·kg-1). The overall mean outdoor terrestrial gamma dose rates fluctuate from 28 to 55 nGy·h-1. The external gamma radiation dose due to natural radionuclides present in the samples have been computed and compared with the global averages. In terms of the radiation safety, the natural radioactivity of the sediment in Egypt is below the recommended limits of the gamma dose rate. Therefore, they can be used for all kinds of public buildings.

关键词：天然放射性核素页岩沙岩埃及

Evaluation of Shell and Tube Heat Exchanger Performance by Using ZnO/Water Nanofluids

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Journal of Harbin Institute of Technology(New Series) 2023年第6期30卷 62-69页

作者： hussein Hayder mohammed Ali Adnan m hussein Kadum mohammed Hussain Allami Barhm mohamad Technical Engineering College/Kirkuk Northern Technical UniversityKirkuk 36001Iraq Computer Engineering Techniques Department Al-Kitab UniversityKirkuk 36001Iraq Department of Petroleum Technology Koya Technical InstituteErbil Polytechnic UniversityErbil 44001Iraq

To examine and investigate the impact of nanofluid on heat exchanger performance,including the total heat transfer,the effect of friction factor,the average Nusselt number,and the thermal efficiency,the output heat transfers of a shell and tube heat exchanger using ZnO nanoparticles suspended in water has been conducted *** governing equations were solved using finite volume techniques and CFD simulations with ANSYS/FLUENT Solver *** nanoparticles volume fractions adopted are 0.2%and 0.35%that used in numerical computations under 200 to 1400 Reynolds numbers *** increasing of temperature is approximately 13%from the bottom to the top of heat exchanger,while the maximum enhancement of Nusselt number is about 10%,19%for volume fractions 0.2%and 0.35%*** elevated values of the friction factor at the volumetric ratios of 0.2%and 0.35%are 0.25%and 0.47%*** findings demonstrate that the performance efficiency of shell and tube heat exchanger is enhanced due to the increase in Nusselt number.

关键词： CFD Reynold number thermal efficiency Nusselt number nanofluid heat exchanger

Synthesis and evaluation of some new oxazolones and imidazolones as antioxidant additives for Egyptian lubricating oils

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Petroleum Science 2012年第3期9卷 389-399页

作者： Ahmed El-mekabaty Osman m.O.Habib hussein m.Hassan Evelin B.moawad Department of Chemistry Faculty of ScienceMansoura University

Oxazolone derivative 2 was utilized as a key intermediate for synthesis of some new oxazolone and imidazolone derivatives. Reaction of oxazolone derivative 2 with diamines under different conditions afforded the corresponding imidazolone derivatives 3-8, respectively. moreover, oxazolone 2 reacted with some heterocyclic amines in glacial acetic acid giving the corresponding imidazolone derivatives 9-14, respectively. Cyclocondensation of thiosemicarbazide with compound 2 in dry pyridine afforded compound 15. Addition of secondary amines to olefin double bond of compound 2 gave the corresponding addition products 16-19, respectively. michael addition of compound 2 with some active methylene compounds afforded oxazolone derivatives 20-23, respectively. These prepared products were evaluated as antioxidant and corrosion inhibitors for gasoline lubricating oil and compounds 6a-e, 10 and 15 exhibited the highest antioxidant and anticorrosive activities. The effect of concentration of additives was studied to recommend the optimum concentration to be used. The results showed, for additive 15, 0.1 g for 1 L oil was the more effective concentration. measurements for thermal analysis and of surface tension of oil after oxidation were also carried out.

关键词： Oxazolone imidazolone benzoimidazole surface tension thermal stability antioxidant additives.

Energy Efficient Scheduler of Aperiodic Jobs for Real-time Embedded Systems

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International Journal of Automation and computing 2020年第5期17卷 733-743页

作者： hussein El Ghor El-Hadi mAggoune University Institute of Technology Lebanese UniversityLebanon Sensor Networks and Cellular Systems(SNCS)Research Center UTSaudi Arabia Electrical Engineering Department University of Tabuk Sensor Networks and Cellular Systems(SNCS)Research Center 71491 TabukSaudi Arabia

Energy consumption has become a key metric for evaluating how good an embedded system is,alongside more performance metrics like respecting operation deadlines and speed of *** improvement is no longer the only metric by which optimality is *** fact,energy efficiency is becoming a preferred choice with a fundamental objective to optimize the system's *** this work,we propose an optimal energy efficient scheduling algorithm for aperiodic real-time jobs to reduce CPU energy ***,we apply the concept of real-time process scheduling to a dynamic voltage and frequency scaling(DVFS)*** address a variant of earliest deadline first(EDF)scheduling algorithm called energy saving-dynamic voltage and frequency scaling(ES-DVFS)algorithm that is suited to unpredictable future energy production and irregular job *** prove that ES-DVFS cannot attain a total value greater than C/ˆSα,whereˆS is the minimum speed of any job and C is the available energy *** also investigate the implications of having in advance,information about the largest job size and the minimum speed used for the competitive factor of *** show that such advance knowledge makes possible the design of semi-on-line algorithm,ES-DVFS∗∗,that achieved a constant competitive factor of 0.5 which is proved as an optimal competitive *** experimental study demonstrates that substantial energy savings and highest percentage of feasible job sets can be obtained through our solution that combines EDF and DVFS optimally under the given aperiodic jobs and energy models.

关键词： Real-time systems energy efficiency aperiodic jobs scheduling dynamic voltage scaling low-power systems embedded systems

Preparation of new and novel wave like poly(2-anisidine) zirconium tungstate nanocomposite: Thermal, electrical and ion-selective studies

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Chinese Journal of Chemical Engineering 2019年第2期27卷 459-466页

作者： Anish Khan Aftab Aslam Parwaz Khan mahmoud A.hussein Bernaurdshaw Neppolian Abdullah m.Asiri Chemistry Department King Abdulaziz University Center of Excellence for Advanced materials Research King Abdulaziz University Polymer Chemistry Laboratory Chemistry Department Faculty of Science Assiut University SRm Research Institute SRM University

It is necessary to synthesize new material for the advancements of the technology. In this study, new and novel poly(2-anisidine)@zirconium tungstate(P2A/ZrW_2O_8) was synthesized by simple so-gel method. Physicochemical characterization of P2A/ZrW_2O_8 was done by thermogravimetric analysis(TGA), scanning electron microscopy(SEm), X-ray powder diffraction(XRD), Fourier transform infrared spectroscopy(FTIR), ion exchange and simultaneous four probe dc conductivity studies. The conductivity study revealed its highly semiconducting nature, in the range of 10^(-1)–10^(-2) S·cm^(-1). Ion-exchange capabilities of the composite make it applicable for cation-exchange studies. The result of distribution studies(Kd) revealed its selectivity towards Cd^(2+) compared to other metal ions. This property of the composite was utilized for designing Cd^(2+) selective membrane electrode. Several important physical parameters of the ion-selective electrode were determined, such as Nernstian slope(32.32 mV·decade^(-1)), working pH range was 2.0–4.0 and response time was found ～ 17 *** analytical utility of this wave like composite membrane electrode was as, indicator electrode in various potentiometric titrations.

关键词： Conducting polymers Electrochemistry Ion-exchangers Electrode Cd^2+ Poly(2-anisidine)

Proteomic profiling reveals engineered chitosan nanoparticles mediated cellular crosstalk and immunomodulation for therapeutic application in apical periodontitis

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Bioactive materials 2022年第5期7卷 77-89页

作者： Hebatullah hussein Anil Kishen The Kishen Lab Dental Research InstituteUniversity of TorontoTorontoON M5G 1G6Canada Faculty of Dentistry University of TorontoTorontoON M5G 1G6Canada Faculty of Dentistry Ain Shams UniversityEndodontics DepartmentCairoEgypt School of Graduate Studies University of TorontoTorontoON M5G 1G6Canada Department of Dentistry Mount Sinai Health SystemMount Sinai HospitalTorontoON M5G 1X5Canada

macrophages(mQ)are major constituents of chronically inflamed periapical tissues in apical *** study aimed to investigate the immunomodulatory effect of engineered bioactive chitosan-based nanoparticles(CSnp)antibiofilm medication on mQ cocultured with periodontal ligament fibroblasts(PdLF).Cells viability,spreading,PdLF migration,and intracellular CSnp uptake were *** mass Tag-based proteomics was applied to analyze mQ global protein expression profiles after interaction with Enterococcus faecalis biofilm,CSnp-treated biofilm,and *** inflammatory mediators were *** bioinformatics analyses,candidate proteins were validated via targeted *** maintained cells viability,increased mQ spreading,and PdLF migration(pmission electron micrographs demonstrated CSnp internalization via macropinocytosis,clathrin-mediated endocytosis,and *** analysis revealed that CSnp-treated biofilm upregulated proteins(>1.5-folds,pment in the pathway of metal sequestration by antimicrobial proteins,while downregulated proteins showed enrichment in *** upregulated proteins exhibiting antioxidant and immunoregulatory *** of SERPINB1 by CSnp(>1.5-folds,pm reduced pro-inflammatory IL-1β and nitric oxide but enhanced anti-inflammatory IL-10 and TGF-β1(pmmed mQ proteomic and cytokine profiles to modulate biofilm-mediated inflammation,and prompted PdLF migration,emphasizing its potential to regulate healing process in the treatment of apical periodontitis.

关键词： Chitosan-based nanoparticles macrophages Immunomodulation Tandem mass tags mass spectrometry Endodontics

Survey and Analysis of VoIP Frame Aggregation methods over A-mSDU IEEE 802.11n Wireless Networks

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Computers, materials & Continua 2021年第2期66卷 1283-1300页

作者： mosleh m.Abualhaj Abdelrahman H.hussein manjur Kolhar mwaffaq Abu AlHija Al-Ahliyya Amman University AmmanJordan Prince Sattam Bin Abdulaziz University Al-KharjSaudi Arabi

The IEEE 802.11n standard has provided prominent features that greatly contribute to ubiquitous wireless *** the last ten years,voice over IP(VoIP)has become widespread around the globe owing to its low-cost or even free call *** combination of these technologies(VoIP and wireless)has become desirable and inevitable for ***,VoIP faces a bandwidth utilization issue when working with 802.11 wireless *** bandwidth utilization is inefficient on the grounds that(i)80 bytes of 802.11/RTP/UDP/IP header is appended to 10–730 bytes of VoIP payload and(ii)765μs waiting intervals follow each 802.11 VoIP *** considering the quality requirements of a VoIP call,be including frame aggregation in the IEEE 802.11n standard has been suggested as a solution for the bandwidth utilization ***,several aggregation methods have been proposed to handle the quality requirements of VoIP calls when carried over an IEEE 802.11n wireless *** this survey,we analyze the existing aggregation methods of VoIP over the A-mSDU IEEE 802.11n wireless *** survey provides researchers with a detailed analysis of the bandwidth utilization issue concerning the A-mSDU 802.11n standard,discussion of the main approaches of frame aggregation methods and existing aggregation methods,elaboration of the impact of frame aggregation methods on network performance and VoIP call quality,and suggestion of new areas to be investigated in conjunction with frame *** survey contributes by offering guidelines to design an appropriate,reliable,and robust aggregation method of VoIP over 802.11n standard.

关键词： VoIP VoIP frame aggregation IEEE 802.11n bandwidth utilization A-mSDU A-mPDU

Grasshopper KUWAHARA and Gradient Boosting Tree for Optimal Features Classifications

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Computers, materials & Continua 2022年第8期72卷 3985-3997页

作者： Rabab Hamed m.Aly Aziza I.hussein Kamel H.Rahouma The Higher Institute for management and Information Technology Minya61768Egypt Department of Electrical and Computer Engineering Effat UniversityJeddahKSA Electrical Engineering Department Faculty of EngineeringMinia UniversityMinia6111Egypt

This paper aims to design an optimizer followed by a Kawahara filter for optimal classification and prediction of employees’*** algorithm starts by processing data by a modified K-means technique as a hierarchical clustering method to quickly obtain the best features of employees to reach their best *** work of this paper consists of two *** first part is based on collecting data of employees to calculate and illustrate the performance of each *** second part is based on the classification and prediction techniques of the employee *** model is designed to help companies in their decisions about the employees’*** classification and prediction algorithms use the Gradient Boosting Tree classifier to classify and predict the *** of the paper give the percentage of employees which are expected to leave the company after predicting their performance for the coming *** also show that the Grasshopper Optimization,followed by“KF”with the Gradient Boosting Tree as classifier and predictor,is characterized by a high *** proposed algorithm is compared with other known techniques where our results are fund to be superior.

关键词： metaheuristic algorithm KUWAHARA filter Grasshopper optimization algorithm and Gradient boosting tree