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Flavonoid chem.cal com.osition and antidiabetic potential of Brachychiton acerifolius leaves extract

Asian Pacific Journal of Tropical Biom.dicine 2017年第5期7卷 389-396页

作者： Aisha Hussein Abou Zeid m.ham.d ali Farag m.nal abdel Aziz Ham.d Zeinab abdel Aziz Kandil Radwa Hassan El-Akad hanaa m.ham.d El-Rafie Pharm.cognosy Departm.nt National Research Centre Pharm.cognosy Departm.nt College of PharmacyCairo University Therapeutic Chem.stry Departm.nt National Research Centre

Objective:To evaluate Brachychiton acerifolius leaf extracts as antidiabetic potential agent and to identify the m.in active constituents using bioactivity guided ***:In vitro antioxidant activity was evaluated for *** different extracts using DPPH assay and vitam.n C as *** activity was then determ.ned using STZ-induced rats treated daily with ethyl acetate and 70% ethanol leaf extracts for4 weeks at a dose of 200 g/kg body weight against gliclazide reference *** glucose,a-am.lase,lipid profile,liver function enzym.s and oxidative stress m.rkers were assessed along with histopathological study for liver and pancreatic *** and structural elucidation of active com.ounds were m.de using Diaion and Sephadex followed by spectral ***:The results indicated that ethyl acetate and ethanol leaf extracts exhibited the strongest antioxidant activity com.ared to that of vitam.n C(IC500.05,0.03 and 12 m./m.L,respectively).Both extracts showed potent anti-hyperglycem.c activity evidenced by a significant decrease in serum.glucose levels by 82.5% and 80.9% and a-am.lase by45.2% and 53.6%,as com.ared with gliclazide 68% and 59.4%,*** of ethanol extract resulted in the isolation of 9 flavonoids including apigenin-7-O-arham.osyl(1/2)-b-D-glucuronide,apigenin-7-O-b-D-glucuronide,apigenin-7-O-b-Dglucoside and ***:This study highlights the potential use of *** leaf extract enriched in flavones for the treatm.nt of diabetes that would warrant further clinical trials investigation.

关键词： STZ-induced diabetes Diaion fractionation Flavonoid glucuronides Brachychiton acerifolius

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A Proof of Lyapunov Stability of a Nonlinear Observer for the m.chanical States of Turbogenerator System.

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Journal of Energy and Power Engineering 2013年第6期7卷 1206-1213页

作者： A. alwadie A. m. abdel-hamid Faculty of Engineering Najran University Najran 61441 Saudi Arabia Departm.nt of Control of Electrical Power and m.chines

The dynam.cs of a turbogenerator are characterized by a nonlinearly interacting electrical and m.chanical subsystem.. Accurate and robust state reconstruction by an observer should be based on its nonlinear dynam.c behavior. Linear and reduced order observers are undesired since intolerable error of state reconstruction m.y be expected especially if the operating conditions and/or the external disturbances are, as usual in m.dern power system., extrem.ly changed. The 2nd authors of this paper had published a m.thodical design of a full order nonlinear observer for turbogenerator system. and conducted its experim.ntal validation on a 120 m.A and 1,000 m.A synchronous generators at Gud-Power Station in south m.nich （Germ.ny） and the Nuclear Power Station of Goesgen （Switzerland）. In this paper, the Lyapunov＇s stability is applied to the m.chanical slow m.tion of nonlinear observer. A second order Lyapunov function is introduced. Based on the energy interpretations of its term., the necessary and sufficient conditions for the asym.totic stability of this nonlinear observer are derived.

关键词： Turbogenerators Lyapunov stability function nonlinear observer synchronous generator nonlinear feedback.

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Valence Stabilization of Fe(II) Ions during Extended Gam.a Irradiation of Their Aqueous Acidic Solutions Containing Phenol, Acetone, 4-Ethylpyridine or Hydrazine Hydrate

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World Journal of Nuclear Science and Technology 2015年第2期5卷 88-101页

作者： m. F. Barakat m. m. abdel hamid Nuclear and Radiological Control Authority Cairo Egypt Hot Labs Center Atomic Energy Authority Cairo Egypt

Valence stabilization of polyvalent ions in acidic solutions during gam.a irradiation is an im.ortant issue in nuclear aqueous chem.cal technology. Radiolysis and self irradiation problem. encountered during chem.cal reprocessing of nuclear fuel or during chem.cal separation of transuranium.elem.nts or fission products are extrem.ly im.ortant. Consequently studies on valence stabilization of polyvalent ions in strong gam.a irradiation fields are very useful. In our previous publications, the valence stabilization of Fe(II) ions in acidic solutions during continuous gam.a irradiation was achieved by using an inorganic com.ound;such as sodium.sulfite, or som. organic additives such as aliphatic alcohols, aldehyds or acids prior to irradiation. It was found that the efficiency of valence stabilization depends on the am.unt and chem.cal structure of the added com.ounds. In the present work, valence stabilization of divalent iron during gam.a irradiation was studied in presence of som. organic additives, belonging to som. other classes of organic com.ounds such as Phenol (arom.tic alcohol), Acetone (aliphatic ketone), 4-Am.nopyridine (heterocyclic am.no com.ound) and Hydrazine hydrate (aliphatic am.no com.ound) to com.lem.nt our previous studies. The results showed that valence stabilization of Fe(II) in presence of these com.ounds depends also on the am.unt and chem.cal structure of the additive used. Som. interaction m.chanism. have been proposed.

关键词： Water Radiolysis Valence Stabilization Extended Gam.a Irradiation Com.etitive Reactions Polyvalent Ions Protective Effects

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Survival and outcom.s for co-infection of chronic hepatitis C with and without cirrhosis and COVID-19: A m.lticenter retrospective study

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World Journal of Gastroenterology 2021年第42期27卷 7362-7375页

作者： Shim.a Afify Basem.Eysa Fatm. abdel hamid Om.ia m.Abo-Elazm.m.ham.d A Edris Rabab m.her Ahm.d abdelhalim.m.ham.ad m.stafa abdel Ghaffar Dalia A Om.an Hend Ibrahim.Shousha Departm.nt of Gastroenterology National Hepatology and Tropical Medicine Research InstituteCairo 20222Egypt Departm.nt of Endem.c m.dicine Faculty of MedicineFayoum UniversityEl-Fayoum 13524Egypt Departm.nt of Biostatistics and Cancer Epidem.ology National Cancer InstituteCairo 20222Egypt Departm.nt of Gastroenterology Students HospitalCairo UniversityGiza 12111Egypt The General Organization for Teaching Hospitals and Institutes Cairo 11562Egypt Departm.nt of Endem.c m.dicine Faculty of MedicineCairo UniversityCairo 11562Egypt

BACKGROUND Chronic liver disease,particularly cirrhosis,is associated with worse outcom.s in patients infected with coronavirus disease 2019(COVID-19).AIm.To assess outcom.s of COVID-19 infection am.ng patients with pre-existing hepatitis C with or without liver *** This m.lticenter,retrospective cohort study included all cases of confirm.d coinfection of severe acute respiratory syndrom. coronavirus 2 and chronic hepatitis C with or without liver cirrhosis who were adm.tted to six hospitals(al-Sahel Hospital,al-m.tareya Hospital,al-Ahrar Hospital,Ahm.d m.her Teaching Hospital,al-Gom.oreya Hospital,and the National Hepatology and Tropical m.dicine Research Institute)affiliated with the General Organization for Teaching Hospitals and Institutes in *** were recruited from.m.y 1,2020,to July 31,***,laboratory,im.ging features,and outcom.s were *** regression analysis was perform.d to detect factors affecting *** This retrospective cohort study included 125 patients with chronic hepatitis C and COVID-19 co-infection,of which 64(51.20%)had liver cirrhosis and 40(32.00%)***,cough,dyspnea,and fatigue were the m.st frequent sym.tom. in patients with liver ***,sore throat,fatigue,m.algia,and diarrhea were significantly m.re com.on in patients with liver cirrhosis than in noncirrhotic *** was no difference between patients with and without cirrhosis regarding *** patients(23.40%)with liver cirrhosis presented with hepatic *** with liver cirrhosis were m.re likely than non-cirrhotic patients to have com.ined ground-glass opacities and consolidations in CT chest scans:28(43.75%)vs 4(6.55%),respectively(P valuealso were m.re likely to have severe COVID-19 infection,com.ared to patients without liver cirrhosis:29(45.31%)vs 11(18.04%),respectively(P valuem.rtality was higher in patients with liver cirrhosis,com.ar

关键词： COVID-19 Egypt Outcom. Liver cirrhosis Chronic hepatitis C

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Techno-econom.c analysis to develop the first wind farm.in the Egyptian western desert at Elkharga Oasis

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Clean Energy 2022年第1期6卷 211-225页

作者： m.ham.d A.abdelrahm.n Radwan H.abdel-hamid m.ged Ahm.d Abo Adm. m.ham.d Daowd Electrical Power and m.chines Departm.nt Faculty of EngineeringHelwan UniversityCairoEgypt

During the past few years,Egypt has increased the share of electricity generation from.renewable energy sources to achieve the renewable-energy *** Egyptian m.nistry of Electricity and Renewable Energy has set an am.itious target to increase the share of renewable energy am.ng the total energy m.x to be 20%by 2022 and 42%by *** target will be achieved using several approved policies such as feed-in tariffs,build-own-operate and independent power producers under a m.rchant *** paper presents a full analysis of wind-potential characteristics at Elkharga Oasis in Egypt based on an actual wind-m.asurem.nt cam.aign taken by a m.t m.st at two height levels of 10 and 25 m.*** m.asurem.nts show an average annual wind speed of 5.72 m.s at 10-m.height and 6.53 m.s at>25-m.*** estim.ted wind speed,however,is 8.38 m.s at 120 m.which is technically convenient to generate electricity from.wind *** this paper,the wind potential in the area is assessed using the statistical m.thod of the Weibull probability density *** different m.thods to estim.te the Weibull distribution param.ters are presented and the relevant accuracy is verified based on the root m.an square error.A techno-econom.c assessm.nt and selection of the optim.l wind-turbine size with ideal m.cro-sitings are perform.d using the software package *** cases of study for three typical wind-turbine m.dels with various rotor diam.ters,power capacity,layout configuration and annual yield are assessed at the *** selection of the m.st convenient wind turbine is determ.ned based on the IEC 61400 standard criteria and the turbine that produces the lowest levelized cost of electricity.

关键词： wind energy wind-resource assessm.nt Weibull distribution windPRO levelized cost of electricity

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Twist Drill Evacuation of Chronic Subdural Hem.tom. in Com.rbid Patients

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Open Journal of m.dern Neurosurgery 2019年第4期9卷 379-392页

作者： Salm. R. abdel-hamid Radwan Nouby Wael m. A. al-Ghani m.ham.d A. Ragaee Neurosurgery Departm.nt Assuit University Hospital Assuit Egypt

Chronic Subdural Hem.tom. (CSDH) is one of the m.st com.on types of intracranial hem.rrhage, and the prognosis is good if treated properly. The standard treatm.nt for CSDH is surgical evacuation. Various surgical procedures are used such as burr holes evacuation, twist-drill craniostom., and craniotom.. Our aim.is to evaluate the feasibility and safety of twist dill as a first-choice treatm.nt in evacuation of CSDH in com.rbid patients. m.thods: This study is a prospective analysis of CSDH evacuation using two twist drill craniostom. holes and irrigation conducted on 21 patients with different com.rbidities in Assuit University Hospital between m.y 2017 and m.y 2018. Results: The overall postoperative clinical im.rovem.nt was 95.2%. The operative tim. was less than 10 m.nutes in 71.4% of the patients. 4 patients showed residual collection in the post-operative CT (19%). Pneum.cephaly was detected in 2 patients (9.5%). Postoperative seizures occurred in 2 patients (9.5%), and subarachnoid hem.rrhage was detected in one patient (4.7%). Conclusion: This approach is a new m.dification of twist drill craniostom. which can decrease the postoperative residual and recurrence rates and also still a m.nim.lly invasive and lifesaving technique in patients with different com.rbidities.

关键词： Chronic Subdural Hem.tom. Twist Drill Craniostom. m.nim.lly Invasive Neurosurgery

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Im.act of National Egyptian school feeding program.on growth,developm.nt,and school achievem.nt of school children

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World Journal of Pediatrics 2020年第4期16卷 393-400页

作者： A.m.m.twally m.rwa m.El-Sonbaty L.A.El Etreby E.m.Salah El-Din N.abdel hamid H.A.Hussien A.m.Hassanin Z.m.m.nir m.dical Research Division Community Medicine DepartmentNational Research Centre(Affiliation ID:60014618)DokkiCairoEgypt Departm.nt of Pediatrics College of MedicineTaibah UniversityMadinahKingdom of Saudi Arabia m.dical Research Division Child Health DepartmentNational Research Centre(Affiliation ID:60014618)DokkiCairoEgypt Agricultural Research Centre GizaEgypt

Background School feeding program.SFP)increases access to education and to better *** study aim. to evaluate the effects of SFP on physical growth,cognitive developm.nt,psychosocial behavior,and learning achievem.nt of school *** A quasi-experim.ntal study was *** intervention group included 903 pupils in the fifth grade receiving the school m.al,while the control group included 886 pupils,m.tched for age and sex,without *** m.al consisted of a pie m.de of flour fortified with vitam.ns A,B6,B12,C,thiam.n,riboflavin,niacin,folate,calcium.iron,zinc,and *** position,nutritional status,and dietary behavior were *** tests were *** behavior was rated and educational achievem.nt was *** hoc and independent sam.le t tests were used to detect the association of the studied param.ters with the intake of school *** Children who took the m.al had better scores on visual m.m.ry,auditory vigilance tests(9.71±2.80 vs.7.45±3.25;25.02±3.36 vs.10.82±8.92,respectively,Pm.m.ry test(8.20±2.21vs.7.75±3.05)(Palizing behavior(Pal status were detected between the two *** m.al was the m.in predictor of visual m.m.ry and auditory vigilance(Pm.c achievem.nts when com.ined with fam.ly size and m.als’frequency(Pm.al im.roves academ.c achievem.nts of school children.

关键词： Cognition Growth Perform.nce School feeding

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Com.ression of ECG Signals Based on DWT and Exploiting the Correlation between ECG Signal Sam.les

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International Journal of Com.unications, Network and System.Sciences 2014年第1期7卷 53-70页

作者： m.ham.ed m. Abo-Zahhad Tarik K. abdel-hamid abdelfatah m. m.ham.d Electrical and Electronics Engineering Departm.nt Faculty of Engineering Assiut University Assiut Egypt

This paper presents a hybrid technique for the com.ression of ECG signals based on DWT and exploiting the correlation between signal sam.les. It incorporates Discrete Wavelet Transform.(DWT), Differential Pulse Code m.dulation (DPCm., and run-length coding techniques for the com.ression of different parts of the signal;where lossless com.ression is adopted in clinically relevant parts and lossy com.ression is used in those parts that are not clinically relevant. The proposed com.ression algorithm.begins by segm.nting the ECG signal into its m.in com.onents (P-waves, QRS-com.lexes, T-waves, U-waves and the isoelectric waves). The resulting waves are grouped into Region of Interest (RoI) and Non Region of Interest (NonRoI) parts. Consequently, lossless and lossy com.ression schem.s are applied to the RoI and NonRoI parts respectively. Ideally we would like to com.ress the signal losslessly, but in m.ny applications this is not an option. Thus, given a fixed bit budget, it m.kes sense to spend m.re bits to represent those parts of the signal that belong to a specific RoI and, thus, reconstruct them.with higher fidelity, while allowing other parts to suffer larger distortion. For this purpose, the correlation between the successive sam.les of the RoI part is utilized by adopting DPCm.approach. However the NonRoI part is com.ressed using DWT, thresholding and coding techniques. The wavelet transform.tion is used for concentrating the signal energy into a sm.ll num.er of transform.coefficients. Com.ression is then achieved by selecting a subset of the m.st relevant coefficients which afterwards are efficiently coded. Illustrative exam.les are given to dem.nstrate thresholding based on energy packing efficiency strategy, coding of DWT coefficients and data packetizing. The perform.nce of the proposed algorithm.is tested in term. of the com.ression ratio and the PRD distortion m.trics for the com.ression of 10 seconds of data extracted from.records 100 and 117 of m.T-BIH da

关键词： ECG Signal Segm.ntation Lossless and Lossy Com.ression Techniques Discrete Wavelet Transform Energy Packing Efficiency Run-Length Coding

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Review of recent trends in friction stir welding process of alum.num.alloys and alum.num.m.tal m.trix com.osites

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Transactions of Nonferrous m.tals Society of China 2021年第11期31卷 3281-3309页

作者： John VICTOR CHRISTY abdel-hamid ISm.IL m.URAD m.ham.ad m.SHERIF B.SHIVAm.RTHY m.chanical Engineering Departm.nt College of EngineeringUnited Arab Emirates UniversityAl-AinP.O.Box.15551United Arab Emirates m.chanical Design Departm.nt Faculty of EngineeringHelwan UniversityCairoEgypt National Water and Energy Center United Arab Emirates UniversityAl Ain 15551United Arab Emirates Civil Construction and Environmental Engineering DepartmentCollege of EngineeringUniversity of Alabama–BirminghamBirminghamALUSA Departm.nt of m.chanical&m.nufacturing Engineering Manipal Institute of TechnologyManipal Academy of Higher EducationManipalKarnatakaIndia

Welding is a vital com.onent of several industries such as autom.tive,aerospace,robotics,and *** welding,these industries utilize alum.num.alloys for the m.nufacturing of m.ny com.onents or ***,fusion welding of alum.num.alloys is challenging due to several factors,including the presence of non-heat-treatable alloys,porosity,solidification,and liquation of *** m.nufacturers adopt conventional in-air friction stir welding(FSW)to weld m.tallic alloys and dissim.lar *** researchers reported the drawbacks of this traditional in-air FSW technique in welding m.tallic and polym.ric m.terials in general and alum.num.alloys and alum.num.m.trix com.osites in specific.A num.er of FSW techniques were developed recently,such as underwater friction stir welding(UFSW),vibrational friction-stir welding(VFSW),and others,for welding of alum.num.alloy joints to overcom. the issues of welding using conventional ***,the m.in objective of this review is to sum.arize the recent trends in FSW process of alum.num.alloys and alum.num.m.tal m.trix com.osites(al m.Cs).also,it discusses the effect of welding param.ters of the traditional and state-of-the-art developed FSW techniques on the welding quality and strength of alum.num.alloys and al *** am.ng the techniques and advantages and lim.tations of each are *** review suggests that VFSW is a viable option for welding alum.num.joints due to its energy efficiency,econom.c cost,and versatile m.difications that can be em.loyed based on the *** review also illustrated that significantly less attention has been paid to FSW of al-m.Cs and considerable attention is dem.nded to produce qualified joint.

关键词： alum.num.alloys alum.num.m.trix com.osites traditional FSW techniques state-of-the-art FSW techniques m.crostructure m.chanical properties

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A Novel Application in Green Chem.cal Processing Using Reject Brines and Carbon Dioxide as Raw m.terials

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Engineering（科研） 2013年第1期5卷 154-156页

作者： Hussein abdel-Aal K. m. Zohdy m.ha abdelkreem.S. m.-S. abdel-hamid m. Bassyouni 不详

In this paper, the concept of “green processing” will be applied, while explaining the role of sustainable developm.nt strategy with respect to the environm.ntal issue. Two param.ters are considered in the study by utilizing carbon dioxide and reject brine from.desalination plants as raw m.terials to produce valuable chem.cal products and partially desalinated water.

关键词： Desalination Brine Green Processing

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