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Hepatoprotective and Antioxidant Activity of Rhizome of Podophyllum hexandrum against Carbon Tetra Chloride Induced Hepatotoxicity in Rats

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Biomedical and Environmental Sciences 2013年第3期26卷 209-221页

作者： Showkat ahmad GANIE Bilal ahmad ZARGAR Akbar MASOOD Mohammad Afzal ZARGAR Department of Biochemistry University of Kashmir Department of Pharmaceutical Sciences University of Kashmir

Objective To test possible antioxidant activity of n-hexane extract of Podophyllum hexandrum under in vitro and in vivo conditions. Methods The in vitro antioxidant activity was evaluated by the ability of the extract to interact with the stable free radical DPPH, Superoxide （02）, Hydroxyl （OH）, Hydrogen peroxide （H202） radicals, and reducing power ability of the extract was also evaluated. Under in vivo conditions the extract was evaluated for its hepatoprotective activity by measuring different biochemical parameters, such as serum alanine aminotransaminase, serum aspartate aminotransaminase and serum lactate dehydrogenase and antioxidant enzymes. Antioxidant status was estimated by determining the activities of antioxidative enzymes, glutathione reductase （GR）, glutathione peroxidase （GPx）, glutathione-S-transferase （GST） and superoxide dismutase （SOD）, and by determining the levels of reduced glutathione （GSH） and thiobarbituric acid reactive substances （TBARS）. Results Hexane extract of P. hexondrum exhibited good radical scavenging capacity in neutralization of DPPH, O2-, OH, and H202 radicals in a dose dependent manner, n-hexane extract of Podophyllum hexandrum at the doses of 20, 30, and 50 mg/kg-day produced hepatoprotective effect by decreasing the activity of serum marker enzymes, while it significantly increased the levels of glutathione （GSH）, glutathione peroxidase （GPx）, glutathione reductase （GR）, super oxide dismutase （SOD）, and glutathione-S-transferase （GST） in a dose dependant manner. The effect of n-hexane extract was comparable to that of standard antioxidant vitamin E. Conclusion The extract of Podophyllum hexandrum possess free radical scavenging activity under in vitro conditions and could protect the liver tissue against CCI4 induced oxidative stress probably by increasing antioxidant defense activities.

关键词： Podophyllum hexandrum Free radicals in-vitro experiments Biochemical parameters Antioxidant Liver protection

Improvement of microstructure and corrosion properties of friction stir welded AA5754 by adding Zn interlayer

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International Journal of Minerals,Metallurgy and Materials 2018年第8期25卷 967-973页

作者： Ali Shamsipur Amir Anvari ahmad Keyvani Department of Mining and Metallurgical Engineering Amirkabir University of Technology School of Metallurgy and Materials Engineering Faculty of Technology and EngineeringShahrekord University

This study investigated the effect of Zn foil layers on the microstructure and corrosion characteristics of friction stir welded aluminum alloy *** of various joints were prepared by applying different rotational and welding speeds,and their microstructures were evaluated via a metallographic technique and scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy elemental *** anticorrosion behavior of joints in the absence and presence of a Zn interlayer was studied by cyclic potentiodynamic polarization test in 3.5 wt% Na Cl aqueous solution,and sound welds were obtained in the presence of the Zn interlayer *** results revealed that the joint made at a rotational speed of 800 r/min and traveling speed of 15 mm/min achieved a chemical composition identical to that of aluminum alloy 7 xxx series,and as such,it showed the best resistance to corrosion.

关键词： friction stir welding AA5754 aluminum alloy zinc interlayer microstructure corrosion resistance

Compaction analysis and optimisation of convex-faced pharmaceutical tablets using numerical techniques

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Particuology 2019年第6期17卷 10-21页

作者： ahmad Baroutaji Sandra Lenihan Keith Bryan School of Engineering Faculty of Science and EngineeringUniversity of WolverhamptonTelfordUK School of Mechanical Electrical and Process EngineeringCork Institute of TechnologyCorkIreland

Capping failure,edge chipping,and non-uniform mechanical properties of convex-faced pharmaceutical tablets are common problems in the pharma *** this paper,the finite element method(FEM)and design of experiment techniques are used to determine the optimal shape of convex-faced(CF)pharmaceutical tablet which has more uniform mechanical properties and less capping and chipping *** effects of different geometrical parameters and friction on the compaction responses of convex-faced pharmaceutical tablets were first identified and *** FEM model of the tabletting process was generated using the implicit code ABAQUS and validated against experimental *** surface methodology was used to establish the relationship between the design variables,represented by the geometrical parameters and friction coefficient,and compaction responses of interest including residual die pressure,relative density variation within a tablet,and relative shear stress at the edge of a tablet.A statistical-based optimisation approach was then used to optimise the shape of CF *** obtained results demonstrated how the geometrical parameters and friction coefficient of CF pharmaceutical tablets strongly affect their compaction behaviour and quality.

关键词： Capping failure Edge chipping Tabletting FEM Optimisation Residual radial pressure

Nanoscale mass sensing based on vibration of single-layered graphene sheet in thermal environments

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Acta Mechanica Sinica 2014年第1期30卷 84-91页

作者： S.ahmad Fazelzadeh Esmaeal Ghavanloo School of Mechanical Engineering Shiraz University

Based on vibration analysis, single-layered graphene sheet （SLGS） with multiple attached nanoparticles is developed as nanoscale mass sensor in thermal environments. Graphene sensors are assumed to be in simplysupported configuration. Based on the nonlocal plate the- ory which incorporates size effects into the classical theory, closed-form expressions lot the frequencies and relative fre- quency shills of SLGS-based mass sensor are derived using the Galerkin method. The suggested model is justified by a good agreement between the results given by the present model and available data in literature. The effects of tem- perature difference, nonlocal parameter, the location of the nanoparticle and the number of nanoparticles on the relative frequency shift of the mass sensor are also elucidated. The obtained results show that the sensitivity of the SLGS- based mass sensor increases with increasing temperature difference.

关键词： Vibration - Single-layered graphene sheet. Ther- mal environment - Nonlocal elasticity theory Relative frequency shift

Influence of soaking time in deep cryogenic treatment on the microstructure and mechanical properties of low-alloy medium-carbon HY-TUF steel

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International Journal of Minerals,Metallurgy and Materials 2016年第6期23卷 658-666页

作者： ahmad Zare S.R.Hosseini Department of Materials Engineering Maleke-ashtar University of Technology

The influence of soaking time in deep cryogenic treatment on the tensile and impact properties of low-alloy medium-carbon HY-TUF steel was investigated in this study. Microstructural studies based on phase distribution mapping by electron backscatter diffraction show that the deep cryogenic process causes a decrease in the content of retained austenite and an increase in the volume fraction of η-carbide with increasing soaking time up to 48 h. The decrease in the content of retained austenite from ~1.23vol% to 0.48vol% suggests an isothermal martensitic transformation at 77 K. The η-type precipitates formed in deep cryogenic-treated martensite over 48 h have the Hirotsu and Nagakura orientation relation with the martensitic matrix. Furthermore, a high coherency between η-carbide and the martensitic matrix is observed by high-resolution transmission electron microscopy. The variations in macrohardness, yield strength, ultimate tensile strength, and ductility with soaking time in the deep cryogenic process show a peak/plateau trend.

关键词： low alloy steel medium carbon steel cryogenic treatment microstructure mechanical properties fractography

Hyper-Tuned Convolutional Neural Networks for Authorship Verification in Digital Forensic Investigations

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Computers, Materials & Continua 2023年第8期76卷 1947-1976页

作者： Asif Rahim Yanru Zhong Tariq ahmad Sadique ahmad Mohammed A.ElAffendi School of Computer and Information Security Guilin University of Electronic TechnologyGuilin541004China Guangxi Key Laboratory of Intelligent Processing of Computer Images and Graphics Guilin University of Electronic TechnologyGuilin541004China School of Information and Communication Guilin University of Electronic TechnologyGuilin541004China EIAS:Data Science and Blockchain Laboratory College of Computer and Information SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia

Authorship verification is a crucial task in digital forensic investigations,where it is often necessary to determine whether a specific individual wrote a particular piece of *** Neural Networks(CNNs)have shown promise in solving this problem,but their performance highly depends on the choice of *** this paper,we explore the effectiveness of hyperparameter tuning in improving the performance of CNNs for authorship *** conduct experiments using a Hyper Tuned CNN model with three popular optimization algorithms:Adaptive Moment Estimation(ADAM),StochasticGradientDescent(SGD),andRoot Mean Squared Propagation(RMSPROP).The model is trained and tested on a dataset of text samples collected from various authors,and the performance is evaluated using accuracy,precision,recall,and F1 *** compare the performance of the three optimization algorithms and demonstrate the effectiveness of hyperparameter tuning in improving the accuracy of the CNN *** results show that the Hyper Tuned CNN model with ADAM Optimizer achieves the highest accuracy of up to 90%.Furthermore,we demonstrate that hyperparameter tuning can help achieve significant performance improvements,even using a relatively simple model architecture like *** findings suggest that the choice of the optimization algorithm is a crucial factor in the performance of CNNs for authorship verification and that hyperparameter tuning can be an effective way to optimize this ***,this paper demonstrates the effectiveness of hyperparameter tuning in improving the performance of CNNs for authorship verification in digital forensic *** findings have important implications for developing accurate and reliable authorship verification systems,which are crucial for various applications in digital forensics,such as identifying the author of anonymous threatening messages or detecting cases of plagiarism.

关键词： Convolutional Neural Network(CNN) hyper-tuning authorship verification digital forensics

Metabolism of energy substrates of in vitro and in vivo derived embryos from ewes synchronized and super ovulated with norgestomet and porcine follicle stimulating hormone

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Journal of Animal Science and Biotechnology 2013年第1期4卷 58-64页

作者： ahmad Azizi-Moghadam Department of Clinical Sciences College of Veterinary Medicine University of Zabol

The synchronization and ovulatory responses of Sangsari cross bred ewes and metabolism of energy substrates in 8-cell stage embryos to hatched blastocysts stage produced in vitro or in vivo were investigated. Ewes were assigned randomly to receive 37.5 IU of porcine follicle stimulating hormone （FSH-P） daily for the 3 days preceding implant removal （Day 0）. Synchronization of estrus was carried out using a 1.5 mg norgestomet （Crestar） ear implant for ] 2 days. Ewes in estrus were mated two to three times with rams of proven fertility. At the time of first mating each ewe was administered 1000 IU of human chorionic gonadotrophin （hCG） to induce ovulation. Surgical embryo recovery was performed on Days 4 and 6 after onset of estrus （Day 0） and recovered embryos were subjected to comparative metabolism studies with in vitro derived embryos at the same stage of development. The number of corpora lutea （CL）, unovulated follicles and overall ovarian activity were recorded for each ewe during the breeding and non-breeding seasons. While the pattern of oxidation was similar among in vitro and in vivo derived embryos, a low pyruvate to lactate ratio was the preferred substrate of embryos derived in vitro. A high level of production of C02 and lactate resulted from a stress response to the suboptimal culture environment. The first marked increase in the metabolism of glucose by ovine embryos was detected in compact morula stage, but there was no significant increase in the oxidation of glucose after the morula stage. Two different concentrations of glucose were compared, but this did not affect metabolism. However, the rate of incorporation and metabolism of glucose tended to be higher at the 0.56 mmol/L glucose dosage.

关键词： Crestar Glucose Lactate Metabolism Norgestomet Pyruvate

Optimization of Manganese and Magnesium Contents in As-cast Aluminum-Zinc-Indium Alloy as Sacrificial Anode

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Journal of Materials Science & Technology 2011年第9期27卷 785-792页

作者： Mohammad R. Saeri ahmad Keyvani Materials Engineering Division Faculty of Engineering Shahrekord University

In this study, effects of manganese and magnesium content on the electrochemical properties of Al-Zn-ln sacrificial anode were studied in 0.5 mol/L NaCl solution （pH=5）. The aluminum base alloy with different amounts of Mn and Mg were melted at 750℃, then casted at molds at 25℃. Corrosion experiments were mounted to determine the optimal effect of Mn and Mg on the efficiencies of the aluminum alloy anodes. The corroded and unexposed sample surfaces were subjected to microstructure characterization by optical and scanning electron microscopy. AI-Zn-ln alloy doped with 0%, 0.01%, 0.05%.0.2% and 0.3% by weights of Mn and 0%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5% and 3.0% by weights of Mg were prepared to determine the effect of Mn and Mg on anode efficiency in the environment. The different microstructures of the evolved AI- Zn-ln-Mg-Mn alloy were correlated with the anode efficiencies. The Al-5.0%Zn-2.0%Mg-0.15%Mn-0.02%ln gave the best anode efficiency （about 83%）. The microstructures of the corroded surface of the optimized alloy revealed decreased distribution of the pockets of localized attacks which are characteristics of pitting （or crevice） corrosion.

关键词： Corrosion Aluminum alloy Sacrificial anode Manganese Magnesium Current capacity

Zero group velocity longitudinal modes in an isotropic cylinder

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Acta Mechanica Sinica 2018年第3期34卷 475-481页

作者： Takasar Hussain Faiz ahmad Muhammad Ozair Department of Mathematics COMSATS Institute of Information Technology School of Natural Sciences National University of Sciences and Technology

Zero group velocity （ZGV） modes are studied in an isotropic cylinder. The L （0, 2） mode behaves anomalously for the materials with a value of the bulk velocity ratio, to, in the range √2 〈 κ 〈 2.64 and normally otherwise. All higher modes, except the first few, have no ZGV point for all isotropic materials. This is explained analytically by finding the slope of phase velocity dispersion curves of modes first when the phase velocity equals κ and then at their initial state.

关键词： Isotropic cylinder Longitudinal modes Zerogroup velocity point