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Protective effects of Balanites aegyptiaca extract, melatonin and ursodeoxycholic acid against hepatotoxicity induced by methotrexate in male rats

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Asian Pacific Journal of Tropical Medicine 2017年第6期10卷 627-634页

作者： Ayat Os Montasser Hanan saleh Omar A.Ahmed-Farid Aida saad mohamed-assem s.marie National Organization for Drug Control And Research Faculty of science Department of Zoology Cairo University

Objective: To compare the degree of ameliorative effects of Melatonin(MEL), Ursodeoxycholic acid(UDCA) and Balanites aegyptiaca(BA) against hepatotoxicity induced by MTX for one month. Methods: Eighty adult male rats(sprague Dawely) weighing(190±10g), were randomly divided into eight equal groups: Control, MTX, MEL, BA, UDCA, MTX+MEL, MTX+BA, MTX+UDCA. Liver function biomarker enzymes, liver tissue oxidative stress parameters, together with total antioxidant capacity and tumor necrosis factor(TNF-α) were determined. Histopathological and immunohistochemistry examinations for TNF-α were also done. Results: MTX showed significant increase in alanine transaminase(ALT), aspartate transaminase(AsT), alkaline phosphatase(ALP), gamma glutamyl transferase(GGT), total and direct bilirubin, as well as TNF-α levels, oxidized glutathione(GssG), malodialdehyde(MDA) and nitric oxide(NO). whereas, total protein, albumin, total antioxidant capacity, reduced glutathione(GsH), glutathione peroxidase(GPx), glutathione reductase(GR), glutathione s-transferase(GsT), superoxide dismutase(sOD) and catalase(CAT) levels were significantly decreased in MTX treated group. These alterations were improved by MEL and BA treatment, whereas no improvement was noticed in UDCA treatment. Conclusions: BA may be as promising as MEL in the hepatoprotection against MTX toxicity through their antioxidant and radical scavenging activities. In addition, it is not recommended to co-administer UDCA with MTX as it enhanced inflammation and damage to the liver.

关键词： Methotrexate Hepatotoxicity Melatonin Balanites aegyptiaca Ursodeoxycholic acid

New LMI Conditions for Reduced-order Observer of Lipschitz Discrete-time systems: Numerical and Experimental Results

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International Journal of Automation and computing 2019年第5期16卷 644-654页

作者： Noussaiba Gasmi assem Thabet mohamed Aoun Research Center for Automatic Control of Nancy CRAN-CNRS UMR 7039University of LorraineCosnes et Romain 54400France Modeling Analysis and Control of Systems(MACS)LaboratoryNational Engineering School of GabesUniversity of GabesGabes 6072Tunisia

The objective of this paper is to propose a reduced-order observer for a class of Lipschitz nonlinear discrete-time *** conditions that guarantee the existence of this observer are presented in the form of linear matrix inequalities(LMIs). To handle the Lipschitz nonlinearities, the Lipschitz condition and the Young′s relation are adequately operated to add more degrees of freedom to the proposed LMI. Necessary and sufficient conditions for the existence of the unbiased reduced-order observer are given. An extension to H_∞ performance analysis is considered in order to deal with H_∞ asymptotic stability of the estimation error in the presence of disturbances that affect the state of the system. To highlight the effectiveness of the proposed design methodology, three numerical examples are considered. Then, high performances are shown through real time implementation using the ARDUINO MEGA 2560 device.

关键词： Reduced-order observer discrete-time systems Lipschitz systems H_∞ ARDUINO MEGA 2560 device

Predictors of spontaneous Bacterial Peritonitis in Patients with Cirrhotic Ascites

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Journal of Clinical and Translational Hepatology 2018年第4期6卷 372-376页

作者： Khaled Metwally Tamer Fouad Medhat assem Eman Abdelsameea mohamed Yousery Hepatology and Gastroenterology department National Liver InstituteMenoufia UniversityEgypt

Background and Aims:spontaneous bacterial peritonitis(sBP)is a serious complication of liver cirrhosis and a prognostic model to predict it is *** study was designed to test the ability of different laboratory tests and the new scoring system by Wehmeyer and colleagues(consisting of age,C-reactive protein(CRP)and platelet count)to predict ***:Three-hundred patients admitted to the National Liver Institute,University of Menoufia,Egypt(2015-2016)with liver cirrhosis and ascites were included in our *** was diagnosed if ascetic neutrophil count was≥250/μL with no sign of secondary ***:The patient population had age range of 29-81 years old,was 60%men and showed a majority(91.7%)with primary cause of liver disease being hepatitis *** univariate analysis,associations with age,total bilirubin,aspartate aminotransferase level,creatinine level,international normalized ratio,model for endstage liver disease score,total leucocytic count,platelet count and CRP level were *** multivariate analysis,independent predictors were age,platelet count and CRP level(p=0.004,0.013 andspectively).CRP at a cut-off point≥13.5 mg/L could predict sBP(sensitivity of 86.4%and specificity of 66.0%).Wehmeyer's sBP scoring system was predictive(ps with 0 score developed sBP(CRP cut-off of 30 mg/L),while 92.8%with score of 3 or 4 developed *** using our modified Wehmeyer score with CRP cut-off value of 13.5 mg/L,no patient with 0 score developed ***:Age,CRP level and platelet count are independent predictors for sBP and a scoring system including them could easily predict the *** diagnosis could be excluded in patients with 0 score,using CRP cut-off value of 13.5 mg/L.

关键词： CRP Predictors sBP Cirrhosis scoring

series solution of a natural convection flow for a Carreau fluid in a vertical channel with peristalsis

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Journal of Hydrodynamics 2015年第6期27卷 969-979页

作者： ABD ELMABOUD Y. MEKHEIMER Kh.s. mohamed mohamed s. Mathematics Department Faculty of Science and ArtsKhulaisUniversity Of Jeddah Mathematics Department Faculty of ScienceAl-Azhar University(Assiut Branch) Mathematics Department Faculty of ScienceTaif University Hawia Mathematics Department Faculty of ScienceAl-Azhar University

An analysis has been achieved to study the natural convection of a non-Newtonian fluid （namely a Carreau fluid） in a vertical channel with rhythmically contracting walls. The Navier-stokes and the energy equations are reduced to a system of non- linear PDE by using the long wavelength approximation. The optimal homotopy analysis method （OHAM） is introduced to obtain the exact solutions for velocity and temperature fields. The convergence of the obtained OHAM solution is discussed explicitly. Numerical calculations are carried out for the pressure rise and the features of the flow and temperature characteristics are analyzed by plotting graphs and discussed in detail.

关键词： homotopy analysis method (HAM) peristaltic transport carreau fluid heat transfer natural convection flow

Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral Mechanical Vibrations in Rotary Drilling systems

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structural Durability & Health Monitoring 2025年第1期19卷 77-103页

作者： sabrina Meddah sid Ahmed Tadjer Abdelhakim Idir Kong Fah Tee mohamed Zinelabidine Doghmane Madjid Kidouche Applied Automation Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Institute of Electrical and Electronic Engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of Industrial Enterprises University of BoumerdesBoumerdes35000Algeria Electrical Engineering Department Mohamed Boudiaf University of M’silaM’sila28000Algeria Department of Civil and Environmental Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Construction and Building Materials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and *** achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is *** study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling *** study speciﬁcally investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency *** events not only hinder the efﬁciency of drilling but also lead to exhaustion and harm to the system’s components since they are difﬁcult to be detected and controlled in real *** study investigates the dynamic interactions of these vibrations,speciﬁcally in their high-frequency modes,usingﬁeld data obtained from measurement while ***ﬁndings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem *** obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control ***,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect ***,by exploiting theseﬁndings,the assessment of structural resilience in rotary drilling systems can be ***,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efﬁciency of rotary drilling systems in the petroleum industry.

关键词： Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis ﬁeld data analysis

Advanced algorithms for retrieving pileup peaks of digital alpha spectroscopy using antlions and particle swarm optimizations

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Nuclear science and Techniques 2020年第4期31卷 47-68页

作者： mohamed s.El_Tokhy Engineering Department NRCAtomic Energy AuthorityP.No.13759InshasEgypt

Optimization algorithms are applied to resolve the second-order pileup(sOP)issue from high counting rates occurring in digital alpha *** are antlion optimizer(ALO)and particle swarm optimization(PsO)*** optimization algorithms are coupled to one of the three proposed peak finder *** custom time-domain algorithms are proposed for retrieving sOP peaks,namely peak seek,slope tangent,and fast array *** addition,an average combinational algorithm is *** time occurrence of the retrieved peaks is tested for an elimination of illusive *** methods are inaccurate and *** and PsO optimizations are used for the localization of retrieved *** cost values that achieve the best fitness values are ***,the optimum positions of the detected peak heights are *** metrics of the optimized algorithms and their influences on the retrieved peaks parameters are *** among such algorithms are investigated,and the algorithms are inspected in terms of their computational time and average *** peak seek algorithm achieves the lowest average computational error for pulse parameters(amplitude and position).However,the fast array algorithm introduces the largest average error for pulse *** addition,the peak seek algorithm coupled with an ALO or PsO algorithm is observed to realize a better performance in terms of the optimum cost and computational *** contrast,the performance of the peak seek recovery algorithm is improved using the ***,the computational time of the peak optimization using the PsO is much better than that of the ALO *** a final conclusion,the accuracy of the peaks detected by the PsO surpasses that for the peaks detected by the *** implemented peak retrieval algorithms are validated through a comparison with experimental results from previous *** proposed algorithms achieve a notable pr

关键词： Alpha spectrometry instrument second-order pileup signal processing Optimization algorithms

Optimal and Memristor-Based Control of A Nonlinear Fractional Tumor-Immune Model

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Computers, Materials & Continua 2021年第6期67卷 3463-3486页

作者： Amr M.s.Mahdy Mahmoud Higazy mohamed s.mohamed Department of Mathematics College of ScienceTaif UniversityTaif21944Saudi Arabia Department of Mathematics Faculty of ScienceZagazig UniversityZagazig44519Egypt Department of Physics and Engineering Mathematics Faculty of Electronic engineeringMenoufia UniversityMenouf32952Egypt Department of Mathematics Faculty of ScienceAl-Azher UniversityNasr City11884Egypt

In this article,the reduced differential transform method is introduced to solve the nonlinear fractional model of *** fractional derivatives are described in the Caputo *** solutions derived using this method are easy and very *** model is given by its signal flow ***,a simulation of the system by the simulink of MATLAB is *** disease-free equilibrium and stability of the equilibrium point are *** of a fractional optimal control for the cancer model is *** addition,to control the system,we propose a novel modification of its *** modification is based on converting the model to a memristive one,which is a first time in the literature that such idea is used to control this type of ***,we study the system’s stability via the Lyapunov exponents and Poincare maps before and after *** order differential equations(FDEs)are commonly utilized to model systems that have memory,and exist in several physical phenomena,models in thermoelasticity field,and biological *** have been utilized to model the realistic biphasic decline manner of elastic systems and infection of diseases with a slower rate of *** are more useful than integer-order in modeling sophisticated models that contain physical phenomena.

关键词： RDTM tumor-immune optimal control caputo derivative signal flow simulink disease-free equilibrium stability memristive lyapunov exponents poincare map

Paraconductivity study in ErBa_2Cu_(3-x)M_xO_(7-δ)(M=Zn, Fe) superconductors

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Chinese Physics B 2013年第11期22卷 562-568页

作者： A.sedky s.B.mohamed Physics Department Faculty of Science King Faisal University Physics Department Faculty of Science Assiut University

We report here the paraconductivity of ErBa2Cu3-xMxO7-δ （M = Zn and Fe） superconductors. The logarithmic plots of excess conductivity Δσ and reduced temperature C reveal two different exponents corresponding to crossover temperature as a result of shifting the order parameter from 2 to 3. The first exponent in the normal field region is close to 1, in which the order parameter dimensionality （OPD） is 2. The second exponent in the critical field region is close to 0.5, in which the OPD is 3. The coherence length, interlayer coupling, interlayer separation and carrier concentration decrease with increasing doping content, and their values for Fe samples are different from those of Zn samples. While anisotropy is increased with increasing doping content, it is generally higher for a Zn sample than that for an Fe sample. We also estimate several physical parameters such as upper critical magnetic fields in the a–b plane and along the c axis （Bab and Bc）, and critical current density J at 0 K. Although Bab and Bc are generally increased with doping content increasing, the value of Bab is found to be twice more than that of Bc. A similar behavior is obtained for J （0 K） and its value is higher in the Fe sample than that in the Zn sample. These results are discussed in terms of oxygen deficiency, localization of carriers, and flux pinning, which are produced by doping.

关键词： ceramics chemical synthesis X-ray diffraction electrical properties transport properties

Numerical Investigation of Rotating stall in Centrifugal Compressor with Vaned and Vaneless Diffuser

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Journal of Thermal science 2015年第4期24卷 323-333页

作者： Taher Halawa mohamed Alqaradawi mohamed s.Gadala Ibrahim shahin Osama Badr Mechanical Engineering Department UBC-University of British ColumbiaVancouverB.C.Canada Mechanical Engineering Department Cairo University Mechanical & Industrial Engineering Department Qatar University Mechanical Engineering Department Abu Dhabi University Mechanical and Industrial Engineering Department Qatar UniversityDohaQatar Mechanical Engineering Department Benha University Mechanical Engineering Department British University

This study presents a numerical simulation of the stall and surge in a centrifugal compressor and presents a description of the stall development in two different *** first case is for a compressor with vaneless diffuser and the second is for a compressor with vaned diffuser of the vane island *** main aim of this study is to compare the flow characteristics and behavior for the two compressors near the surge operating condition and provide further understanding of the diffuser role when back flow occurs at *** showed that for a location near the diffuser entrance,the amplitude of the static pressure fluctuations for the vaneless diffuser case is higher than that for the vaned diffuser case near surge *** pressure fluctuations in the case of the vaneless diffuser appear with a gradual decrease of the mean pressure value as a part of the surge *** for the case of the vaned diffuser,the pressure drop during surge occurs faster than the case of the vaneless ***,results indicated that during surge in the case of vaneless diffuser,there is a region with low velocity and back flow that appears as a layer connecting all impeller passages near shroud surface and this layer develops in size with *** the other hand,for the case of vaned diffuser during surge,the low velocity regions appear in random locations in some passages and these regions expand with time towards the shroud *** showed that during stall,the impeller passages are exposed to identical impact from stall cells in the case of vaneless diffuser while the stall effect varies from passage to another in the case of the vaned diffuser.

关键词： centrifugal compressors rotating stall surge vaneless diffuser vaned diffuser