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Chinese Physics Letters 2017年第6期34卷 70-74页

作者： E.f.el-Shamy Department of.Physics College of ScienceKing Khalid University Department of.Physics Faculty of ScienceDamietta University

The nonlinear propagation of.positron acoustic periodic （PAP） travelling waves in a magnetoplasma composed of.dynamic cold positrons, superthermal kappa distributed hot positrons and electrons, and stationary positive ions is examined. The reductive perturbation technique is employed to derive a nonlinear Zakharov Kuznetsov equation that governs the essential f.atures of.nonlinear PAP travelling waves. Moreover, the bif.rcation theory is used to investigate the propagation of.nonlinear PAP periodic travelling wave solutions. It is f.und that kappa distributed hot positrons and electrons provide only the possibility of.existence of.nonlinear compressive PAP travelling waves. It is observed that the superthermality of.hot positrons, the concentrations of.superthermal electrons and positrons, the positron cyclotron f.equency, the direction cosines of.wave vector k along the z-axis, and the concentration of.ions play pivotal roles in the nonlinear propagation of.PAP travelling waves. Tile present investigation may be used to understand the f.rmation of.PAP structures in the space and laboratory plasmas with superthermal hot positrons and electrons.

关键词： Nonlinear Propagation of.Positron-Acoustic Periodic Travelling Waves in a Magnetoplasma with Superthermal electrons and Positrons

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Ef.ect of.adipose-derived mesenchymal stem cells on hepatocellular carcinoma: In vitro inhibition of.carcinogenesis

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World Journal of.Gastroenterology 2019年第5期25卷 567-583页

作者： Rim Serhal Nagib Saliba George Hilal Mayssam Moussa ghada S Hassan Oula el Atat Nada Alaaeddine Regenerative Medicine Laboratory Faculty of Medicine Saint-Joseph University Surgery Department Faculty of Medicine Saint-Joseph University and Hotel-Dieu de France Cancer and Metabolism Laboratory Faculty of Medicine Campus of Medical Sciences Saint-Joseph University Laboratoire d’Immunologie Cellulaire et Moléculaire Centre Hospitalier de l’Université de Montréal

AIM To investigate the ef.ect of.adipose-derived mesenchymal stem cells(ADMSCs)and their conditioned media(CM) on hepatocellular carcinoma(HCC) cell *** The prolif.ration rate of.HepG2 and PLC-PRf.5 HCC cancer cells was measured using the trypan blue exclusion method and conf.rmed using the cell-counting kit8(commonly known as CCK-8) assay. Apoptosis was detected by f.ow cytometry using annexin V-f.TC. Protein and mRNA expression was quantif.ed by elISA and real time PCR, respectively. Migration and invasion rates were perf.rmed by Transwell migration and invasion assays. Wound healing was examined to conf.rm the data obtained f.om the migration *** Our data demonstrated that when co-culturing HCC cell lines with ADMSCs or treating them with ADMSC CM, the HCC cell prolif.ration rate was signif.cantly inhibited and the apoptosis rate increased. The decreased prolif.ration rate was accompanied by an upregulation of.P53 and Retinoblastoma mRNA and a downregulation of.c-Myc and hTERT mRNA levels. More notably, ADMSCs and their CM suppressed the expression of.the two important markers of.HCC carcinogenicity, alpha-f.toprotein and Des-gamma-carboxyprothrombin. In addition, the migration and invasion levels of.HepG2 and PLC-PRf.5 cells signif.cantly decreased, potentially through increased expression of.the tissue inhibitor metalloproteinases TIMP-1, TIMP-2 and *** These f.ndings shed new light on a protective and therapeutic role f.r ADMSCs and their CM in controlling HCC invasiveness and carcinogenesis.

关键词： Hepatocellular carcinoma Adipose-derived mesenchymal stem cells Adipose-derived mesenchymal stem cell conditioned media Prolif.ration Apoptosis Migration Invasion

Activity of.f.sf.mycin in Extended-Spectrum Beta-Lactamases Producing Klebsiella pneumonae f.om Hospital Acquired Urinary Tract Inf.ctions

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Open Journal of.Medical Microbiology 2016年第3期6卷 104-111页

作者： ghada el-Saeed Mashaly Medical Microbiology and Immunology Department Faculty of Medicine Mansoura University Egypt

Treatment of.hospital acquired urinary tract inf.ctions (UTIs) caused by extended-spectrum beta-Lactamases producing Klebsiella pneumonae is a major problem. This organism expresses a high level of.resistance to many groups of.antibiotics. f.sf.mycin is an agent which is recommended f.r treatment of.UTIs caused by ESBLs producers. The aim of.this study is to determine the sensitivity pattern of.ESBLs producing urinary K. pneumonae to antimicrobial agents including f.sf.mycin in patients of.MUHs and determine the prevalence of.f.sf.mycin resistance mediated by plasmid mediated f.sf.mycin modif.ing enzymes f.sA, f.sB and f.sA3. Methods: Klebsiella pneumonae urinary isolates were collected f.om patients with hospital acquired UTIs in Mansoura University Hospitals (MUHs). The susceptibility pattern was determined by Kirby Baur method. Isolates resistant to extended spectrum cephalosporins were tested f.r ESBLs production by double disc dif.usion method. f.sf.mycin resistance was determined by broth dilution method. Isolates resistant to f.sf.mycin were tested f.r f.sA, f.sB and f.sA3 by PCR. Results: A total of.128 ESBLs producing K. pneumonae isolates were collected. The highest sensitivity was to imipenem (94.5%). The lowest was to trimethoprime-sulphamethoxazole (21.8%). Co-resistance of.ESBLs isolates with f.sf.mycin was 23.2%. Eighteen f.sf.mycin resistant isolates (18/30) were positive to f.sA. Conclusion: ESBLs producing urinary Klebsiella pneumonae express moderate sensitivity to f.sf.mycin. Resistance is mainly mediated by plasmid mediated f.sf.mycin modif.ing enzymes f.sA.

关键词： Klebsiella pneumonae Extended-Spectrum Beta-Lactamases f.sf.mycin Urinary Tract Inf.ction Plasmid Mediated Resistance

f.oc meal as potential substitute f.r soybean meal in tilapia diets under biof.oc system conditions

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Journal of.Oceanology and Limnology 2019年第1期37卷 313-320页

作者： Rania S. MABROKE Osama M. el-HUSSEINY Abd el-Naem f. A. ZIDAN Al-Azab TAHOUN Ashraf.SULOMA f.sh Nutrition Laboratory (f.L) Animal Production Department Faculty of Agriculture Cairo University Aquaculture Department Faculty of Fish ResourcesSuez University

This study was conducted to evaluate the ef.f.ct of.replacing soybean meal(SBM) by low protein ?oc meal(LPf.; 24% CP) in tilapia diets on growth perf.rmance, f.ed utilization and ?sh chemical composition. Three isonitrogenous and isocaloric diets were f.rmulated; control diet(C; without LPf.),f. 25(25% of.SBM protein was substituted by LPf.) and f. 50(50% of.SBM protein was substituted by LPf.). Nine 55 l circular plastic tanks were stocked by 12 ?sh to f.rm three experimental *** dif.f.rences in tilapia perf.rmance were observed between the control and the f. 25 diet. Chemical composition of.?sh did not dif.f.r signi?cantly among treatments except f.r protein and selenium contents where the highest values were recorded in the control treatment. The highest mineral content was recorded in ?oc collected f.om the control tanks, while calcium content showed its highest value in ?oc collected f.om f. 50 e ? uent. These data indicate that replacing soybean meal with LPf. up to 25%, had no negative ef.f.ct on growth perf.rmance and potentially may improve the system sustainability. Meanwhile, the adverse ef.f.ct of.more inclusion of.LPf. in tilapia diet may be attributed to the higher content of.ash. In other word,minerals seem to cause more energy utilization in ?sh f.d ?oc meal since it is needed to maintain osmotic homeostasis.

关键词： microbial f.ocs alternative protein sources tilapia diet sustainability

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Ef.ect of.substitution group on dielectric properties of.4H-pyrano [3,2-c] quinoline derivatives thin f.lms

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Chinese Physics B 2016年第7期25卷 440-449页

作者： H M Zeyada f.M el-Taweel M M el-Nahass M M el-Shabaan Department of.Physics Faculty of Science Damietta University Department of.Chemistry Faculty of Science Damietta University Department of.Physics Faculty of Education Ain Shams University

The AC electrical conductivity and dielectrical properties of.2-amino-6-ethyl-5-oxo-4-（3-phenoxyphenyl）-5,6-dihydro-4H-pyrano[3, 2-c]quinoline-3-carbonitrile（Ph-HPQ） and 2-amino-4-（2-chlorophenyl）-6-ethyl-5-oxo-5,6-dihydro-4H-pyrano [3, 2-c] quinoline-3-carbonitrile（Ch-HPQ） thin f.lms were determined in the f.equency range of.0.5 k Hz–5 MHz and the temperature range of.290–443 K. The AC electrical conduction of.both compounds in thin f.lm f.rm is governed by the correlated barrier hopping（CBH） mechanism. Some parameters such as the barrier height, the maximum barrier height, the density of.charges, and the hopping distance were determined as f.nctions of.temperature and f.equency. The phenoxyphenyl group has a greater inf.uence on those parameters than the chlorophenyl group. The AC activation energies were determined at dif.erent f.equencies and temperatures. The dielectric behaviors of.Ph-HPQ and Ch-HPQ were investigated using the impedance spectroscopy technique. The impedance data are presented in Nyquist diagrams f.r dif.erent temperatures. The Ch-HPQ f.lms have higher impedance than the Ph-HPQ f.lms. The real dielectric constant and dielectric loss show a remarkable dependence on the f.equency and temperature. The Ph-HPQ has higher dielectric constants than the Ch-HPQ.

关键词： thin f.lms quinoline derivatives dielectrical properties correlated barrier hopping

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Implementing Ef.ective Learning with Ubiquitous Learning Technology During Coronavirus Pandemic

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Computer Systems Science & Engineering 2022年第1期40卷 389-404页

作者： Hosam f.el-Sof.ny Samir A.el-Seoud King Khalid University AbhaKingdom of Saudi Arabia Cairo Higher Institute f.r Engineering Computer Science and ManagementCairoEgypt British University in Egypt—BUE Faculty of Informatics and Computer ScienceCairoEgypt

Ubiquitous computing supports U-learning to develop and implement a new educational environment that provides ef.ective and interactive learning to students wherever they *** study aims to present a qualitative evaluation f.r using U-learning instead of.traditional education to avoid the spread of.the Coronavirus *** authors introduce a UTAUT(Unif.ed Theory of.Acceptance and Use of.Technology)model to assess the capability of.the given f.ctors that are expected to af.ect the learners’intention and behavior f.r accepting the U-learning technology f.r f.ll *** research study shows a promising impact on the use of.U-learning apps f.r implementing their learning activities in both the present and coming *** study also presents the descriptive statistics that af.ect the students’answers by using U-learning while implementing learning assignments including exams,projects,f.rums,essays,presentations,and *** research experiments demonstrate both the composite reliability(CR)and the average variance extracted(AVE)of.the presented *** experimental results have shown that(1)the f.ctor loadings≥0.75,CR≥0.9,and AVE≥0.75,which present appropriate proof.f.r the validity and reliability of.the proposed model,and(2)the total average of.students that accept the U-learning is 82.99%,and who disagree is 8.13%,while who neither agree nor disagree is 6.44%.

关键词： Ubiquitous learning U-learning E-learning M-learning COVID-19 pandemic coronavirus UTAUT model

Highlights in pathogenesis of.vitiligo

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World Journal of.Clinical Cases 2015年第3期3卷 221-230页

作者： ghada f.Mohammed Amal Hussein Gomaa Mohammed Saleh Al-Dhubaibi Department of.Dermatology and Venereology Faculty of Medicine Suez Canal University Department of.Dermatology Faculty of Medicine Qassim University

Vitiligo is a common pigmentary disorder. Many studies across decades and all over the world have attempted to illustrate the pathogenesis behind it; however, the pathogenesis of.vitiligo remains elusive. This review article, we present the f.ndings behind the most and updated theories behind this psychologically debilitating and disf.guring disease. The discussion begun with the role of.genetic predisposition f.llowed by neural theory f.rst proposed in the 1950 s. Wehighlight the autoimmune hypothesis, f.llowed by the reactive oxygen species model, zinc-α2-glycoprotein def.ciency hypothesis, viral theory, intrinsic theory and biochemical, molecular and cellular alterations accounting f.r loss of.f.nctioning melanocytes in vitiligo. Many theories were elaborated to clarif. vitiligo pathogenesis. It is a multif.ctorial disease involving the interplay of.several f.ctors. f.ture research is needed to clarif. the interaction of.these f.ctors f.r better understanding of.vitiligo pathogenesis and subsequent successf.l treatment.

关键词： Etiopathogenesis Pigmentary disorder Non-segmental vitiligo Segmental vitiligo Vitiligo

f.rmation of.Alf.énic supernonlinear waves in a plasma containing double spectral distributed electrons

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Communications in Theoretical Physics 2024年第12期76卷 140-149页

作者： A A el-Tantawy W f.el-Taibany S K el-Labany A M Abdelghany Department of.Physics Faculty of Science Damietta University Center of.Space Research and Its Application Damietta University

The characteristics of.nonlinear and supernonlinear Alf.én waves propagating in a multicomponent plasma composed of.a double spectral electron distribution and positive and negative ions were investigated. The Sagdeev technique was employed, and an energy equation was derived. Our f.ndings show that the proposed system reveals the existence of.a double-layer solution, periodic, supersoliton, and superperiodic waves. The phase portrait and potential analysis related to these waves were investigated to study the main f.atures of.existing waves. It was also f.und that decreasing the electron temperature helps the superperiodic structure to be excited in our plasma model. Our results help interpret the nonlinear and supernonlinear f.atures of.the recorded Alf.én waves propagating in the ionosphere D-region.

关键词： Alf.én waves double spectral distribution nonlinear waves Sagdeev method supernonlinear waves

Annexin A2 as a biomarker f.r hepatocellular carcinoma in Egyptian patients

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World Journal of.Hepatology 2017年第9期9卷 469-476页

作者： Mohamed K Shaker Hanzada I Abdel f.ttah ghada S Sabbour Iman f.Montasser Sara M Abdelhakam Eman el Hadidy Rehab Yousry Ahmed K el Dorry Department of.Tropical Medicine Faculty of MedicineAin Shams University Department of.Clinical Pathology Faculty of MedicineAin Shams University Department of.Radiodiagnosis and Inter-ventional Radiology Faculty of MedicineAin Shams University

AIM To investigate the clinical utility of.serum annexin A2(ANXA2) as a diagnostic marker f.r early hepatocellular carcinoma(HCC).METHODS This study was perf.rmed in HCC Clinic of.Ain Shams University Hospitals, Cairo, Egypt and included: Group 1: f.f.y patients with early stage HCC(Barcelona Clinic Liver Cancer stage A); Group 2: Twenty f.ve patients with chronic liver disease; and Control Group: f.f.een healthy, age-and sex-matched subjects who were seronegative f.r viral hepatitis markers. The f.llowinglaboratory investigations were done: Viral hepatitis markers [hepatitis B surf.ce antigen and hepatitis C virus(HCV) antibodies], HCV RNA in HCV antibody-positive patients, serum alpha f.toprotein(Af.), and serum ANXA2 *** In this study, 88% of.HCC patients(n = 44) were HCVpositive, while HBV inf.ction represented only 8% of.all HCC patients(n = 4); and two patients were negative f.r both viral markers. A highly signif.cant dif.erence was f.und between patients with HCC and chronic liver disease as well as controls with regard to serum ANXA2 levels(130, IQR 15-240; 15, IQR 15-17; and 17, IQR 15-30 ng/m L, respectively). The area under the curve of.ANXA2 was 0.865; the cut-of. value was established to be 18 ng/mL with a diagnostic sensitivity of.74% and a specif.city of.88%, while the sensitivity and specif.city of.Af. at the cut-of. value of.200 ng/dL were 20% and 100%, *** Serum ANXA2 may serve as a biomarker f.r the early detection of.HCC.

关键词： Hepatocellular carcinoma Hepatitis C virus Annexin A2 Alpha-f.toprotein Tumor markers

Metaheuristic Optimization Through Deep Learning Classif.cation of.COVID-19 in Chest X-Ray Images

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Computers, Materials & Continua 2022年第11期73卷 4193-4210页

作者： Nagwan Abdel Samee el-Sayed M.el-Kenawy ghada Atteia Mona M.Jamjoom Abdelhameed Ibrahim Abdelaziz A.Abdelhamid Noha E.el-Attar Tarek Gaber Adam Slowik Mahmoud Y.Shams Department of.Inf.rmation Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh 11671Saudi Arabia Department of.Communications and electronics Delta Higher Institute of Engineering and TechnologyMansoura 35111Egypt f.culty of.Artif.cial Intelligence Delta University for Science and TechnologyMansoura 35712Egypt Department of.Computer Sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh 11671Saudi Arabia Computer Engineering and Control Systems Department Faculty of EngineeringMansoura University35516MansouraEgypt Department of.Computer Science Faculty of Computer and Information SciencesAin Shams University11566CairoEgypt Department of.Computer Science College of Computing and Information TechnologyShaqra University11961Saudi Arabia f.culty of.Computers and Artif.cial Intelligence Benha UniversityEgypt School of.Science Engineeringand EnvironmentUniversity of SalfordUK f.culty of.Computers and Inf.rmatics Suez Canal UniversityIsmailia41522Egypt Koszalin University of.Technology Poland f.culty of.Artif.cial Intelligence Kafrelsheikh UniversityKafrelsheikh33511Egypt

As corona virus disease(COVID-19)is still an ongoing global outbreak,countries around the world continue to take precautions and measures to control the spread of.the *** of.the excessive number of.inf.cted patients and the resulting def.ciency of.testing kits in hospitals,a rapid,reliable,and automatic detection of.COVID-19 is in extreme need to curb the number of.*** analyzing the COVID-19 chest X-ray images,a novel metaheuristic approach is proposed based on hybrid dipper throated and particle swarm *** lung region was segmented f.om the original chest X-ray images and augmented using various transf.rmation ***,the augmented images were f.d into the VGG19 deep network f.r f.ature *** the other hand,a f.ature selection method is proposed to select the most signif.cant f.atures that can boost the classif.cation ***,the selected f.atures were input into an optimized neural network f.r *** neural network is optimized using the proposed hybrid *** experimental results showed that the proposed method achieved 99.88%accuracy,outperf.rming the existing COVID-19 detection *** addition,a deep statistical analysis is perf.rmed to study the perf.rmance and stability of.the proposed *** results conf.rm the ef.ectiveness and superiority of.the proposed approach.

关键词： Covid-19 f.ature selection dipper throated optimization particle swarm optimization deep learning