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Hypolipidemic activity of Tamarix articulata Vahl. in diabetic rats

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Journal of Integrative Medicine 2017年第6期15卷 476-482页

作者： morad hebi mohamed eddouks faculty of sciences and techniques errachidia moulay ismail universityBoutalamine52000 Errachidia Morocco

OBJECTIVE： Tamarix articulata Vahl. （Tamaricaceae） is a medicinal plant commonly used in Morocco for the treatment of diabetes mellitus and cardiovascular diseases. The objective of this study was to evaluate the hypolipidemic activity of aqueous extract of T. articulata in normal and streptozotocin （STZ）-induced diabetic rats. Phytochemical analysis as well as determination of polyphenol and flavonoid contents in the aqueous extract of T. articulata was performed. METHODS： The effects of oral administration of aqueous extract of T. articulata （5 mg/kg） on the plasma total cholesterol, triglyceride and high-density lipoprotein cholesterol （HDL-c） concentrations were measured in both normal and STZ-induced diabetic rats. Total phenolic content of the aqueous extract was determined by Folin-Ciocalteu method. In addition, determination of flavonoid content was performed using colorimetric AICI3 method. RESULTS： A single oral administration in diabetic rats induced a significant increase in the HDL-c concentration after 6 h of treatment with T. articulata （5 mg/kg）. The results also demonstrated that the aqueous extract of T. articulata produced a significant decrease of serum total cholesterol after repeated oral administration in diabetic rats （P 〈 0.01）. The total polyphenol and flavonoid contents of T. articulata aqueous extract were equal to 102.50 mg of gallic acid equivalent per gram of extract and 54.83 mg of quercetin equivalent per gram of extract, respectively. CONCLUSION： According to preliminary phytochemical screening of the aerial part of T. articulata, severa classes of chemicals have been found, such as polyphenols, flavonoids, tannins, cyanidins （flavones, catechols）, mucilage, sesquiterpenes, terpenoids and carbohydrates. In conclusion, T. articulata exhibits a hypolipidemic effect in diabetic rats and its beneficial role as hypolipidemic agent should be evaluated in clinical studies.

关键词： hypolipidemic streptozotocin total cholesterol triglycerides flavonoids

Ensuring the possibility of using thorium as a fuel in a pressurized water reactor(PWR)

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Nuclear Science and Techniques 2021年第12期32卷 37-52页

作者： mohamed Y.M.Mohsen mohamed A.E.Abdel-Rahman AAbdelghafar Galahom Nuclear Engineering Department Military Technical CollegeKobry ElkobbahCairoEgypt Higher Technological Institute 10th of Ramadan CityEgypt

The possibility of utilizing thorium as a fuel in a pressurized water reactor(PWR)has been proven from the neutronic perspective in our previously published work without assessing the thermal hydraulic(TH)and solid structure ***,the TH and solid structure performances must be studied to confirm these results and ensure the possibility of using a thorium-based fuel as an excellent accident-tolerant *** TH and solid structure performances of thorium-based fuels were investigated and compared with those of UO_(2).The radial and axial power peaking factors(PPFs)for UO_(2),(^(232)Th,^(235)U)O_(2),and(^(232)Th,^(233)U)O_(2)were examined with a PWR assembly to determine the total PPF of each *** Gd_(2)O_(3)and Er_(2)O_(3)were tested as burnable absorbers(BAs)to manage the excess reactivity at the beginning of the fuel cycle(BOC)and reduce the total ***_(2)O_(3)resulted in a more significant reduction to the total PPF and,therefore,a greater reduction to the temperature distribution compared to Gd_(2)O_(3).Given these results,we analyzed the effects of adding Er_(2)O_(3)to thorium-based fuels on their TH and solid structure performances.

关键词： Thermal hydraulic(TH) Solid structure Thorium-based fuel Gd2O3 Er_(2)O_(3)

Performance of Free Space Optical Communication System Based on M-ary PPM Modulation over Double Generalized Gamma Channel

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China Communications 2020年第4期17卷 19-30页

作者： mohamed maalej Hichem Besbes Higher School of Communications of Tunis University of Carthage2083 El Ghazala ArianaTunisia

In this paper, we provide analytical results on average Symbol Error Probability(SEP) of a Free Space Optics(FSO) link employing M-ary Pulse Position Modulation(PPM), subjected to turbulent atmosphere modeled with Double Generalized Gamma(DGG) distribution. FSO link is generally impaired by turbulent atmosphere and pointing errors. As far as we know, results are presented in previous works by considering the atmosphere turbulence modeled with a Gamma-Gamma distribution. In our work, we also give asymptotic results on average SEP in order to approximate its evolution at high Signal-to-Noise-Ratio(SNR). Numerical results showed that FSO link performance is enhanced when PPM-modulation index is increased, for both strong and moderate turbulence regimes, and for both strong and weak pointing error jitter. Monte-Carlo simulations were presented to corroborate our analytical expressions.

关键词： FSO DGG atmospheric turbulence PPM modulation SEP pointing error

The effect of atomic spontaneous decay on the dynamics of the negativity of the Wigner function of radiation

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Chinese Physics B 2011年第9期20卷 44-48页

作者： Abdel-Baset A.mohamed Faculty of Science Assiut UniversityAssiutEgypt

The exact solution of the master equation for the case of a high-Q cavity with atomic decay is found. We use the negativity of the Wigner function （WF） as an indicator of nonclassicality. It is found that the negative values of the field WF are very sensitive to any change in the damping parameter. The atomic spontaneous decay leads to the simultaneous disappearance of both entanglement and nonclassicality of quantum states. Moreover, the purity of the field states is completely lost.

关键词： non-classicality entanglement atomic decay

Computing Connected Resolvability of Graphs Using Binary Enhanced Harris Hawks Optimization

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Intelligent Automation & Soft Computing 2023年第5期36卷 2349-2361页

作者： Basma mohamed Linda Mohaisen mohamed Amin mathematics and Computer Science Department Faculty of ScienceMenoufia UniversityShebin Elkom32511Egypt Faculty of Computer and Information Technology King Abdulaziz UniversityJeddah21589Saudi Arabia

In this paper,we consider the NP-hard problem ofﬁnding the minimum connected resolving set of graphs.A vertex set B of a connected graph G resolves G if every vertex of G is uniquely identiﬁed by its vector of distances to the ver-tices in B.A resolving set B of G is connected if the subgraph B induced by B is a nontrivial connected subgraph of *** cardinality of the minimal resolving set is the metric dimension of G and the cardinality of minimum connected resolving set is the connected metric dimension of *** problem is solved heuristically by a binary version of an enhanced Harris Hawk Optimization(BEHHO)*** is theﬁrst attempt to determine the connected resolving set *** combines classical HHO with opposition-based learning,chaotic local search and is equipped with an S-shaped transfer function to convert the contin-uous variable into a binary *** hawks of BEHHO are binary encoded and are used to represent which one of the vertices of a graph belongs to the connected resolving *** feasibility is enforced by repairing hawks such that an addi-tional node selected from V\B is added to B up to obtain the connected resolving *** proposed BEHHO algorithm is compared to binary Harris Hawk Optimi-zation(BHHO),binary opposition-based learning Harris Hawk Optimization(BOHHO),binary chaotic local search Harris Hawk Optimization(BCHHO)*** results conﬁrm the superiority of the BEHHO for determining connected metric dimension.

关键词： Connected resolving set binary optimization harris hawks algorithm

Robust Adaptive Control for Mobile manipulators

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International Journal of Automation and computing 2011年第1期8卷 8-13页

作者： mohamed Boukattaya Tarak Damak mohamed Jallouli Control of Industrial Process Unit National School of Engineers University of Sfax Intelligent Control Design and Optimization of Complex Systems Unit National School of Engineers University of Sfax

This paper addresses the trajectory tracking control of a nonholonomic wheeled mobile manipulator with parameter uncertainties and disturbances. The proposed algorithm adopts a robust adaptive control strategy where parametric uncertainties are compensated by adaptive update techniques and the disturbances are suppressed. A kinematic controller is first designed to make the robot follow a desired end-effector and platform trajectories in task space coordinates simultaneously. Then, an adaptive control scheme is proposed, which ensures that the trajectories are accurately tracked even in the presence of external disturbances and uncertainties. The system stability and the convergence of tracking errors to zero are rigorously proven using Lyapunov theory. Simulations results are given to illustrate the effectiveness of the proposed robust adaptive control law in comparison with a sliding mode controller.

关键词： Mobile manipulator trajectory tracking robust adaptive control sliding mode control uncertainties and disturbances.

Unknown Inputs Observer for a Class of Nonlinear Uncertain Systems: An LMI Approach

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International Journal of Automation and computing 2012年第3期9卷 331-336页

作者： Kamel mohamed Mohammed Chadli mohamed Chaabane Industrial Process Control Unit National Engineering School of Sfax University of Picardie Jules Verne MIS (EA 4290). 7 rue Moulin Neuf 80000 Amiens France

This paper deals with the simultaneous estimation of states and unknown inputs for a class of Lipschitz nonlinear systems using only the measured outputs. The system is assumed to have bounded uncertainties that appear on both the state and output matrices. The observer design problem is formulated as a set of linear constraints which can be easily solved using linear matrix inequalities (LMI) technique. An application based on manipulator arm actuated by a direct current (DC) motor is presented to evaluate the performance of the proposed observer. The observer is applied to estimate both state and faults.

关键词： Unknown inputs observer uncertain nonlinear systems Lipschitz condition bounded uncertainties linear matrix inequality (LMI)

Performance Evaluation and Effectiveness of the Reverberation Room

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Sound & Vibration 2021年第1期55卷 43-55页

作者： mohamed Abd-Elbasseer Hatem Kh mohamed Acoustics Laboratory National Institute of Standards(NIS)GizaEgypt

This research presents a thorough evaluation of the reverberation room at Acoustics Laboratory in National Institute of Standards(NIS)according to the related international *** evaluation aims at examining the room performance and exploring its effectiveness in the frequency range from 125 Hz to 10000 Hz according to the international standard *** room,which was designed and built several years ago,is an irregular rectangular shape free from *** volume is about 158.84 m^(3),which meets the requirement of the ISO 354 standard Lmaxmay be due to a lack of diffusivity of the sound field at this *** evaluation proves that the NIS reverberation room is in full agreement with the international standards,which in turns qualifies the room to host measurements inside without concerns.

关键词： Reverberation room cut-off frequency sound absorption spatial uniformity modal counts

Ore Controls and Metallogenesis of Au-Ag Deposits at Atalla Mine,Central Eastern Desert of Egypt

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Acta Geologica Sinica(English Edition) 2020年第5期94卷 1451-1470页

作者： mohamed ABD EL MONSEF Geology Department Faculty of ScienceTanta UniversityTanta 31527Egypt Institute of Geological Sciences Faculty of ScienceMasaryk UniversityBrnoCzech Republic

Gold-silver deposits in the Atalla area occur as hydrothermal quartz veins in NE–SW pre-existing fractures within the Atalla granitic *** orientation of such quartz veins has been attributed to extensional behavior related to the Atalla Shear Zone(ASZ).The Atalla area is covered by a variety of lithologies that are(from oldest to youngest):metasedimentary rocks,metavolcanic rocks,ophiolite assemblage(serpentinites/talc-carbonates),Atalla granite and Dokhan volcanic ***,Atalla granite ranges in composition from granodiorite to *** geochemistry constrains the calc-alkaine affinity of the Atalla granite that was intruded within an orogenic(syncollision)tectonic *** ore minerals are represented by gold/silver(electrum),pyrite(Py1&Py2),arsenopyrite,pyrrhotite,sphalerite,chalcopyrite,galena,covellite and *** temperature of ore formation ranges from 240 to 285℃and the estimated fluid pressure is in the range of 20–100 *** on the geological setting,ore textures and fluid characteristics;the Atalla Au-Ag deposits are considered to be orogenic in nature,formed from a continental collision(~653-590 ma),synchronous with the emplacement of calc-alkaline magmatism during the evolutionary history of the Arabian Nubian Shield(ANS).The initial ore-forming fluid was primarily derived from a metamorphic source related to ophiolitic-serpentinite rocks under deep regional conditions of greenschist-amphibolite facies,where the Atalla granitic eruption provided the required temperature conditions for the metamorphic process to take *** such conditions,the transportation of ore metals as bisulfide complexes is *** deposition of ore minerals was triggered by fluidwallrock interaction through fracture pathways in conjunction with a temperature-pressure drop that is likely to have been related to uplift into the crustal levels.

关键词： Gold-silver arsenopyrite geothermometry fluid inclusions orogenic deposits Atalla Shear Zone(ASZ)