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Bougainvillea spectabilis flowers extract protects against the rotenone-induced toxicity

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Asian Pacific Journal of Tropical medicine 2017年第5期10卷 457-466页

作者： Omar m.E.abdel-Salam Eman R.Youness Nadia A.ahmed Sayed A.El-Toumy ahmed m.A.Souleman Nermeen Shaffie Dalia m.Abouelfadl Department of Toxicology and Narcotics National Research CentreCairoEgypt Department of medical Biochemistry National Research CentreCairoEgypt Department of Chemistry of Tannins National Research CentreCairoEgypt Department of Phytochemistry and Plant Systematic National Research CentreCairoEgypt Department of Pathology National Research CentreCairoEgypt

Objective:To investigate the effect of two extracts of Bougainvillea spectabilis(B. spectabilis) flowers with yellow and pink/purple on brain oxidative stress and neuronal damage caused in rats by systemic rotenone injection. methods:Rotenone 1.5 mg/kg was given three times per week alone or in combination with B. spectabilis flowers extracts(25 mg or 50 mg) via the subcutaneous route for 2 weeks. Brain concentrations of the lipid peroxidation marker malondialdehyde(mDA),reduced glutathione,nitric oxide(nitrite),the pro-inflammatory cytokine interleukin-1beta(Il-1β) as well as butyrylcholinesterase,and paraoxonase-1(PON-1) activities,were determined. Histopathology and caspase-3 immunohistochemistry were also performed. Results:Rotenone resulted in significant increases of brain mDA(the product of lipid peroxidation),and nitric oxide content along with decreased brain reduced glutathione. There were also marked and significant inhibition of brain PON-1 and BCh E activities and increased Il-1β in brain of rotenone-treated rats. B. spectabilis flowers extract itself resulted in brain oxidative stress increasing both lipid peroxidation and nitrite content whilst inhibiting PON-1 activity. The yellow flowers extract inhibited BCh E activity and increased brain Il-1β. When given to rotenone-treated rats,B. spectabilis extracts,however,decreased lipid peroxidation while their low administered doses increased brain GSH. Brain nitrite decreased by the pink extract but showed further increase by the yellow extract. Either extract,however,caused further inhibition of PON-1 activity while the yellow extract resulted in further inhibition of BChE activity. Histopathological studies indicated that both extracts protected against brain,liver and kidney damage caused by the toxicant. Conclusions:These data indicate that B. spectabilis flowers extracts exert protective effect against the toxic effects of rotenone on brain,liver and kidney. B. spectabilis flowers extracts decreased

关键词： Bougainvillea spectabilis Flowers Extract Rotenone Oxidative stress Parkinson’s disease

Boundary layer flow of maxwell fluid due to torsional motion of cylinder: modeling and simulation

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Applied mathematics and mechanics(English Edition) 2020年第4期41卷 667-680页

作者： m.KHAN A.ahmed J.ahmed Department of mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

This paper investigates the boundary layer flow of the maxwell fluid around a stretchable horizontal rotating cylinder under the influence of a transverse magnetic *** constitutive flow equations for the current physical problem are modeled and analyzed for the first time in the *** torsional motion of the cylinder is considered with the constant azimuthal velocity *** partial differential equations(PDEs)governing the torsional motion of the maxwell fluid together with energy transport are simplified with the boundary layer *** current analysis is valid only for a certain range of the positive Reynolds ***,for very large Reynolds numbers,the flow becomes ***,the governing similarity equations are simplified through suitable transformations for the analysis of the large Reynolds *** numerical simulations for the flow,heat,and mass transport phenomena are carried out in view of the bvp4c scheme in *** outcomes reveal that the velocity decays exponentially faster and reduces for higher values of the Reynolds numbers and the flow penetrates shallower into the free stream *** is also noted that the phenomenon of stress relaxation,described by the Deborah number,causes to decline the flow fields and enhance the thermal and solutal energy transport during the fluid *** penetration depth decreases for the transport of heat and mass in the fluid with the higher Reynolds *** excellent validation of the numerical results is assured through tabular data with the existing literature.

关键词： torsional motion maxwell fluid magnetic field stretchable rotating cylinder bvp4c scheme

Transient flow of magnetized maxwell nanofluid: Buongiorno model perspective of Cattaneo-Christov theory

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Applied mathematics and mechanics(English Edition) 2020年第4期41卷 655-666页

作者： m.KHAN A.ahmed J.ahmed Department of mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

The present research article is devoted to studying the characteristics of Cattaneo-Christov heat and mass fluxes in the maxwell nanofluid flow caused by a stretching sheet with the magnetic field *** maxwell nanofluid is investigated with the impact of the Lorentz force to examine the consequence of a magnetic field on the flow characteristics and the transport of *** heat and mass transport mechanisms in the current physical model are analyzed with the modified versions of Fourier’s and Fick’s laws,***,the well-known Buongiorno model for the nanofluids is first introduced together with the Cattaneo-Christov heat and mass fluxes during the transient motion of the maxwell *** governing partial differential equations(PDEs)for the flow and energy transport phenomena are obtained by using the maxwell model and the Cattaneo-Christov theory in addition to the laws of *** transformations are used to convert the PDEs into a system of nonlinear ordinary differential equations(ODEs).The homotopic solution methodology is applied to the nonlinear differential system for an analytic *** results for the time relaxation parameter in the flow,thermal energy,and mass transport equations are discussed *** is noted that higher values of the thermal and solutal relaxation time parameters in the Cattaneo-Christov heat and mass fluxes decline the thermal and concentration fields of the ***,larger values of the thermophoretic force enhance the heat and mass transport in the ***,the Brownian motion of the nanoparticles declines the concentration field and increases the temperature *** validation of the results is assured with the help of numerical tabular data for the surface velocity gradient.

关键词： transient flow Cattaneo-Christov theory maxwell nanofluid Buongiorno model homotopy analysis method (HAm) solution

Thermal analysis in swirl motion of maxwell nanofluid over a rotating circular cylinder

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Applied mathematics and mechanics(English Edition) 2020年第9期41卷 1417-1430页

作者： A.ahmed m.KHAN J.ahmed Department of mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

In this paper,the mechanism of thermal energy transport in swirling flow of the maxwell nanofluid induced by a stretchable rotating cylinder is *** rotation of the cylinder is kept constant in order to avoid the induced axially secondary ***,the novel features of heat generation/absorption,thermal radiation,and Joule heating are studied to control the rate of heat *** effects of Brownian and thermophoretic forces exerted by the maxwell nanofluid to the transport of thermal energy are investigated by utilizing an effective model for the nanofluid proposed by *** whole physical problem of fluid flow and thermal energy transport is modelled in the form of partial differential equations(PDEs)and transformed into nonlinear ordinary differential equations(ODEs)with the help of the suitable flow *** acquired results through the technique bvp4c are reported graphically with physical *** analysis reveals that there is higher transport of heat energy in the maxwell nanoliquid for a constant wall temperature(CWT)as compared with the prescribed surface temperature(PST).Both thermophoretic and Brownian forces enhance the thermal energy transport in the flowing maxwell ***,the temperature distribution increases with increasing values of the radiation parameter and the Eckert *** is also noted that an increase in Reynolds number reduces the penetration depth,and as a result the flow and transport of energy occur only near the surface of the cylinder.

关键词： maxwell nanofluid rotating cylinder heat source/sink Joule heating convective condition numerical solution

mycogenic Silver Nanoparticles From Endophytic Trichoderma atroviride with Antimicrobial Activity

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Journal of Renewable materials 2020年第2期8卷 171-185页

作者： ahmed abdel-Azeem Amr A.Nada Anthonia O’Donovan Vijay Kumar Thakur Amr Elkelish microbiology Section Department of BotanyFaculty of ScienceUniversity of Suez CanalIsmailia41522Egypt Department of Analysis and Evaluation Egyptian Petroleum Research InstituteNasr CityCairoP.B.11727Egypt Institut Européen des membranes IEMUMR-5635Univ MontpellierENSCMCNRSMontpellierFrance School of Science and Computing Galway-Mayo Institute of TechnologyGalwayIreland Enhanced Composites and Structures Center School of AerospaceTransport and ManufacturingCranfield UniversityBedfordshireUK Botany Section Department of BotanyFaculty of ScienceUniversity of Suez CanalIsmailia41522Egypt

There is an increasing interest in developing nanoparticles with diverse biologic *** this end,we prepared 10 to 15 nm silver nanoparticles(AgNP)from native isolates of Trichoderma *** this study,endophytic fungi hosted four medicinal plants in Saint Katherine Protectorate,South Sinai,Egypt have been isolated by surface sterilization technique on four isolation *** species,based on their frequency of occurrence,out of twenty recovered taxa were tested for their capability to synthesize extracellular *** atroviride hosted Chiliadenus montanus was found to be the best candidate for the production of mycogenic AgNPs among all examined *** mycosynthesized AgNPs were compared with chemically synthesized and characterized using Ultraviolet-visible(UV-vis)spectroscopy,Raman spectroscopy,X-ray diffraction(XRD)and high-resolution transmission electron microscopy(HRTEm)*** HRTEm result showed the distribution of spherical AgNPs ranging from 10 to 15 *** atroviride isolate was subjected to sequencing for confirmation of phenotypic *** internal transcribed spacer(ITS)1-5.8 s-ITS2 rDNA sequences obtained were compared with those deposited in the GenBank Database and registered with accession number mH283876 in the NCBI ***,anticandidal and antifungal effects of chemically and mycosynthesized AgNPs were examined at various concentrations in vitro against six pathogenic bacteria and 4 pathogenic fungi by agar well diffusion *** antibiotics;Gentamicin,Amoxicillin,Clotrimazole,and Nystatin at 5μg/disk were taken as positive controls,while 5%DmSO was used as the negative *** data revealed that the application of mycogenic AgNPs at a concentration of 100 ppm resulted in maximum inhibition of pathogenic bacteria and *** data suggest that AgNPs from native isolates of Trichoderma atroviride(mH283876)offer a source of rapid synthesis of eco-friendly,e

关键词： Antimicrobial endobionts mycogenic AgNPS Saint Katherine Protectorate

Slip flow and variable properties of viscoelastic fluid past a stretching surface embedded in a porous medium with heat generation

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Journal of Central South University 2016年第4期23卷 991-999页

作者： ahmed m.megahed Department of mathematics Faculty of Science Benha University (13518)

This study examines theoretically and computationally the non-Newtonian boundary layer flow and heat transfer for a viscoelastic fluid over a stretching continuous sheet embedded in a porous medium with variable fluid properties, slip velocity, and internal heat generation/absorption. The flow in boundary layer is considered to be generated solely by the stretching of the sheet adjacent to porous medium with boundary wall slip condition. Highly nonlinear momentum and thermal boundary layer equations governing the flow and heat transfer are reduced to set of nonlinear ordinary differential equations by appropriate transformation. The resulting ODEs are successfully solved numerically with the help of shooting method. Graphical results are shown for non-dimensional velocities and temperature. The effects of heat generation/absorption parameter, the porous parameter, the viscoelastic parameter, velocity slip parameter, variable thermal conductivity and the Prandtl number on the flow and temperature profiles are presented. moreover, the local skin-friction coefficient and Nusselt number are presented. Comparison of numerical results is made with the earlier published results under limiting cases.

关键词： viscoelastic fluid variable fluid properties slip velocity

Variable fluid properties and variable heat flux effects on the flow and heat transfer in a non-Newtonian maxwell fluid over an unsteady stretching sheet with slip velocity

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Chinese Physics B 2013年第9期22卷 480-485页

作者： ahmed m. megahed Department of mathematics Faculty of ScienceBenha University

The effects of variable fluid properties and variable heat flux on the flow and heat transfer of a non-Newtonian maxwell fluid over an unsteady stretching sheet in the presence of slip velocity have been studied. The governing differential equations are transformed into a set of coupled non-linear ordinary differential equations and then solved with a numerical technique using appropriate boundary conditions for various physical parameters. The numerical solution for the governing non-linear boundary value problem is based on applying the fourth-order Runge-Kutta method coupled with the shooting technique over the entire range of physical parameters. The effects of various parameters like the viscosity parameter, thermal conductivity parameter, unsteadiness parameter, slip velocity parameter, the Deborah number, and the Prandtl number on the flow and temperature profiles as well as on the local skin-friction coefficient and the local Nusselt number are presented and discussed. Comparison of numerical results is made with the earlier published results under limiting cases.

关键词： maxwell fluid unsteady stretching sheet variable fluid properties variable heat flux

Kaoline-based catalyst for a high stability desulfurization of sour heavy naphtha in a three-phase oscillatory baffled reactor

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Particuology 2024年第1期84卷 249-260页

作者： Hassan m.Hmood Saba A.Gheni Safaa m.R.ahmed mudheher m.Ali hamid Yonis Saleh mohammed H.mohammed Awad E.mohammed marwan A.mahomood Hiba R.mohammed ahmed A.Hassan Adam Harvey North Refineries Company Ministry of OilIraq Chemical Engineering Department Tikrit UniversityIraq ministry of Oil Iraq AL-Hawija Technical Institute Northern Technical UniversityMoselIraq School of Engineering Newcastle UniversityUK

To meet the rapidly increasing demand for energy and the dramatic depletion of conventional crude oil,it is imperative to utilize sour *** no coke being produced,oxidative desulfurization(ODS)of naphtha lowers its sulfur content and average molecular *** this article,we outline a method for heavy naphtha non-extractive ODS using a very stable *** technique involves the use of a solid catalyst with oxygen gas as the *** necessitated relatively high mixing intensities;hence a three-phase Oscillatory Baffled Reactor(OBR)was *** catalyst was based on the zeolite ZSm-5,prepared from natural kaolin by a series of delamination and activation steps and impregnated with Fe.A TiO2 nanolayer was applied,using the sol-gel method,to prevent rapid *** reactor performance was evaluated to minimize the sulfur content in the naphtha *** to the protective coating,the sulfur conversion stabilized at 90%.The results of this work establish the use of natural clay-based catalysts in a continuous,three-phase ODS,particularly with regard to proving long-term *** also showed that modest ODS can be achieved using an environmentally friendly oxidant,at mild operating conditions,whilst maintaining stability.

关键词： Natural kaoline Desulfurization Three-phase Oscillatory baffled reactor

Interrelationship between Toll-like receptors and infection after orthotopic liver transplantation

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World Journal of Transplantation 2020年第6期10卷 162-172页

作者： mahmoud El-Bendary mustafa Naemattalah ahmed Yassen Naser mousa Dina Elhammady ahmed m Sultan mohamed abdel-Wahab Department of Tropical medicine and Hepatology Faculty of MedicineMansoura UniversityMansoura 35111Egypt Department of medical Biochemistry Faculty of MedicineMansoura UniversityMansoura 35111Egypt Gastroenterology Surgical Centre Faculty of MedicineMansoura UniversityMansoura 35111Egypt

Early microbial recognition by the innate immune system is accomplished by Toll-like receptors(TLRs),with resultant initiation of a pro-inflammatory response against infecting *** spite of presence of an abundance of Toll-like receptors on the surface of the liver,gut bacteria does not elicit an inflammatory reaction in healthy individuals due to tolerance to these TLRs,suggesting that the inflammatory responses seen in the liver are the result of breakdown of this *** orthotopic liver transplantation is often life saving in many instances,death following this procedure is most commonly due to infection that occurs in up to 80%of transplant recipients,most commonly due to microbial causes in up to 70%of cases and viral infections in 20%,while fungal infections affect only 8%of *** probability of acquiring infection following hepatic transplantation is heightened due to affection of the innate immune defense mechanisms of the host following this *** nucleotide polymorphisms of TLRs have been associated with increased likelihood of either development of post-transplant infection or eradication of infecting ***,conflicting reports from other studies reveal that prevalence of this single nucleotide polymorphism is not increased in infected patients.

关键词： Toll like receptors Infection Liver transplantation Cirrhosis Immunity Orthotopic