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Mechanisms of alcohol-mediated hepatotoxicity in human-immunodeficiency-virus-infected patients

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World Journal of Gastroenterology 2011年第20期17卷 2500-2506页

作者： Gyongyi Szabo samir Zakhari Department of Medicine LRB-208 University of Massachusetts Medical School National Institute on Alcohol Abuse and Al coholism National Institutes of Health

Clinical observations have demonstrated that excessive chronic alcohol use negatively affects human immuno- deficiency virus (HIV) infection and contributes to the liver manifestations of the disease, even in HIV mono- infection. HIV/hepatitis C virus (HCV) co-infection is as- sociated with increased progression of HVC liver disease compared to HCV infection alone, and both of these are negatively affected by alcohol use. Recent data suggest that alcohol use and HIV infection have common targets that contribute to progression of liver disease. Both HIV infection and chronic alcohol use are associated with increased gut permeability and elevated plasma levels of lipopolysaccharide; a central activator of inflammatory responses. Both alcoholic liver disease and HIV infec tionresult in non-specific activation of innate immunity, proinflammatory cytokine cascade upregulation, as well as impaired antigen presenting cell and dendritic cell functions. Finally, alcohol, HIV and antiretroviral therapyaffect hepatocyte functions, which contributes to liver damage. The common targets of alcohol and HIV infection in liver disease are discussed in this minireview.

关键词：艾滋病毒感染肝脏疾病酒精性毒性机制人类免疫缺陷病毒丙型肝炎病毒介导患者

Spatial Variability and Cartography of Maximum Annual Daily Rainfall under Different Return Periods in Northern Algeria

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Journal of Mountain Science 2015年第6期12卷 1403-1421页

作者： MEDDI Mohamed TOUMI samir National High School of Hydraulic (ENSH)

The estimation of precipitation quantiles has always been an area of great importance to meteorologists, hydrologists, planners and managers of hydrotechnical infrastructures. In many cases, it is necessary to estimate the values relating to extreme events for the sites where there is little or no measurement, as well as their return periods. A statistical approach is the most used in such cases. It aims to find the probability distribution that best fits the maximum daily rainfall values. In our study, 231 rainfall stations were used to regionalize and find the best distribution for modeling the maximum daily rainfall in Northern Algeria. The L-moments method was used to perform a regionalization based on discordance criteria and homogeneity test. It gave rise to twelve homogeneous regions in terms of LCoefficient of variation(L-CV), L-Skewness(L-CS) and L-Kurtosis(L-CK). This same technique allowed us to select the regional probability distribution for each group using the Z statistic. The generalized extreme values distribution(GEV) was selected to model the maximum daily rainfall of 10 groups located in the north of the steppe region and the generalized logistic distribution(GLO) for groups representing the steppes of Central and Western Algeria. The study of uncertainty by the bias and RMSE showed that the regional approach is acceptable. We have also developed maximum daily rainfall maps for 2, 5, 10, 20, 50 and 100 years return periods. We relied on a network of 255 rainfall stations. The spatial variability of quantiles was evaluated by semi-variograms. All rainfall frequency models have a spatial dependence with an exponential model adjusted to the experimental semi-variograms. The parameters of the fitted semi-variogram for different return periods are similar, throughout, while the nugget is more important for high return periods. Maximum daily rainfall increases from South to North and from West to East, and is more significant in the coastal areas of ea

关键词：阿尔及利亚空间变异性日降雨量重现期降水量 Logistic分布区域概率分布广义极值分布

Re-evaluation of several heavy metals removal by natural limestones

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Frontiers of Chemical Science and Engineering 2014年第4期8卷 418-432页

作者： Ali SDIRI samir BOUAZIZ Laboratory of Water Energy and Environment National Engineering School University of Sfax Sfax 1173-3038 Tunisia

Different treatment technologies have been efficiently applied to remove heavy metals from waste- water. Efforts have been made to find out the most economic water treatment technology by using low cost and easily accessible natural materials. On the other hand, heavy metals are the most threatening groundwater contaminants because of their toxicity and harmful effects on human and biota. This review discusses the use of natural geological materials for heavy metal removal in aqueous systems. Special attention has been devoted to natural limestone through a systematic inventory of relevant published reports. The removal of toxic metals may include different mechanisms （e.g., physisorption, chemisorptions, precipitation, etc.）, depending on the physico-chemical properties of the material and the removed metal. Sorption of toxic metals （e.g., Pb, Cu, Cd, Zn, Cr, Hg, etc.） onto natural limestone involved precipitation of metal carbonate as a predominant removal process, but often subordinated by adsorption and ion exchange, depending on the physico-chemical properties of the studied limestone.

关键词： limestone heavy metals sorption waste-water passive treatment technology

Numerical study on discharge characteristics influenced by secondary electron emission in capacitive RF argon glow discharges by fluid modeling

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Chinese Physics B 2018年第2期27卷 415-422页

作者：赵璐璐刘悦 Tagra samir Key Laboratory of Materials Modification by Laser Ion and Electron Beams (Ministry of Education) School of PhysicsDalian University of Technology School of Information Science and Engineering Dalian Polytechnic University

A one-dimensional（1D） fluid model of capacitive RF argon glow discharges between two parallel-plate electrodes at low pressure is employed. The influence of the secondary electron emission on the plasma characteristics in the discharges is investigated numerically by the model. The results show that as the secondary electron emission coefficient increases,the cycle-averaged electric field has almost no change; the cycle-averaged electron temperature in the bulk plasma almost does not change, but it increases in the two sheath regions; the cycle-averaged ionization rate, electron density, electron current density, ion current density, and total current density all increase. Also, the cycle-averaged secondary electron fluxes on the surfaces of the electrodes increase as the secondary electron emission coefficient increases. The evolutions of the electron flux, the secondary electron flux and the ion flux on the powered electrode increase as the secondary electron emission coefficient increases. The cycle-averaged electron pressure heating, electron Ohmic heating, electron heating, and ion heating in the two sheath regions increase as the secondary electron emission coefficient increases. The cycle-averaged electron energy loss increases with increasing secondary electron emission coefficient.

关键词： RF glow discharge secondary electron emission fluid model

Fuzzy Adaptive Control of a Fractional Order Chaotic System With Unknown Control Gain Sign Using a Fractional Order Nussbaum Gain

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IEEE/CAA Journal of Automatica Sinica 2019年第3期6卷 816-823页

作者： Khatir Khettab samir Ladaci Yassine Bensafia IEEE the Electrical Engineering Department University of Mohamed Boudiaf M’sila 28000 Algeria Electrical Engineering Department University of Skikda the EEA Department National Polytechnic School of Constantine B. P. 75 A Ali Mendjli 25000 Constantine Algeria SP-Lab Laboratory Department of Electronics Mentouri University Yassine Bensafia is with the Electrical Engineering Department University of Bouira

In this paper we propose an improved fuzzy adaptive control strategy, for a class of nonlinear chaotic fractional order(SISO) systems with unknown control gain sign. The online control algorithm uses fuzzy logic sets for the identification of the fractional order chaotic system, whereas the lack of a priori knowledge on the control directions is solved by introducing a fractional order Nussbaum gain. Based on Lyapunov stability theorem, stability analysis is performed for the proposed control method for an acceptable synchronization error level. In this work, the Gr ¨unwald-Letnikov method is used for numerical approximation of the fractional order systems. A simulation example is given to illustrate the effectiveness of the proposed control scheme.

关键词： Adaptive fuzzy control chaos synchronization fractional order Nussbaum function Lyapunov stability nonlinear fractional order systems

Application of artificial intelligence techniques in modeling attenuation behavior of ionization radiation: a review

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Radiation Detection Technology and Methods 2023年第1期7卷 56-83页

作者： Joseph Konadu Boahen samir A.Elsagheer Mohamed Ahmed S.G.Khalil Mohsen A.Hassan Materials Science and Engineering Department School of Innovative Design EngineeringEgypt-Japan University of Science and Technology(E-JUST)P.O.Box 179New Borg El-Arab CityEgypt Computer Science and Information Technology Programs Egypt-Japan University of Science and Technology(E-JUST)AlexandriaEgypt Faculty of Engineering Aswan UniversityAswanEgypt Institute of Basic and Applied Science Egypt-Japan University of Science and Technology(E-JUST)179 New Borg El-Arab CityAlexandriaEgypt Environmental and Smart Technology Group Faculty of ScienceFayoum UniversityFayoum63514Egypt

Introduction Shielding of ionizing radiations,which are gamma rays,neutrons,and X-rays,can be achieved by attenuating its intensity using different *** is therefore crucial in ensuring the safety of lives and essential equipment in areas such as nuclear power plants,radiotherapy facilities,space exploration,and *** Intelligent technologies have become desirable in modeling shielding materials’attenuation behavior due to their unique *** The overview aims to present the recent application of AI technologies in modeling the radiation attenuation behavior of *** A total of 41 relevant articles were obtained using Scopus and web of science *** search was restricted to articles and conference papers published within the last two *** From the overview,it was realized that AI techniques can predict the attenuation properties of shielding materials and optimize the shield *** methods can be grouped into predictive models which are:fuzzy logic,Support Vector Regression,Neural Networks,and optimization models which include Genetic algorithms,Ant Colony,and Particle Swarm *** networks are the most robust and widely used *** predictive models are used in predicting parameters such as attenuation coefficient,buildup factor,shield thickness,and radiation dose rates,whiles the optimization techniques are employed in single and multi-objective attenuator *** In the overview,the accuracies and complexities of the various AI techniques have been discussed giving insight into their *** AI techniques are easy to model compared to conventional methods and can save computational time when coupled with conventional statistical and deterministic models or employed as a standalone technique.

关键词： Ionization radiation Attenuation behavior Artificial intelligence Modeling

Effects of cathodic component of current on porosity and hardness characteristics of micro plasma oxidation(MPO) coatings on aluminum alloy

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中国有色金属学会会刊：英文版 2005年第1期15卷 113-118页

作者： samir Hamid Awad 钱翰城 School of Mechanical Engineering Chongqing University Chongqing 400044 China

Micro plasma oxidation(MPO) has recently been investigated as a novel, rapid and effective means to provide modified surfaces with improved properties of load bearing and wear resistance on light alloys particularly aluminum alloys. MPO is a multifactor-controlled process, these factors must be controlled to produce high quality coatings. The main research emphasis in MPO coating development over the past years seems to be the attainment of higher hardness levels and thick coatings. The porosity of MPO coating is the most complex phenomenon affecting the distribution, levels and the measurements of the hardness; and it is controlled by suitable selection of important parameters such as the electrical conditions. Ceramics coatings were synthesized on Al substrate by MPO to examine the effects of adding a cathodic phase alternated with anodic-cathodic current on the porosity and hardness characteristics of coatings by X-ray diffraction(XRD), scanning electron microscopy(SEM), and microhardness tester. The coatings produced by the combined mode are more dense and less porous than that by the anodic-cathodic mode. (Microhardness) test shows that the coatings produced by the combined mode exhibit both the highest hardness, and less reduction percentage in hardness with increasing the coatings thickness. These improvements become more significant for the polished and thicker coatings.

关键词：微观等离子体氧化铝合金硬度多孔材料

Effects of gas pressure on plasma characteristics in dual frequency argon capacitive glow discharges at low pressure by a self-consistent fluid model

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Chinese Physics B 2017年第12期26卷 361-370页

A self-consistent fluid model for dual radio frequency argon capacitive glow discharges at low pressure is established. Numerical results are obtained by using a finite difference method to solve the model numerically, and the results are analyzed to study the effect of gas pressure on the plasma characteristics. It shows that when the gas pressure increases from 0.3 Torr （1 Torr=1.33322102 Pa） to 1.5 Torr, the cycle-averaged plasma density and the ionization rate increase; the cycle-averaged ion current densities and ion energy densities on the electrodes electrode increase; the cycle-averaged electron temperature decreases. Also, the instantaneous electron density in the powered sheath region is presented and discussed. The cycle-averaged electric field has a complex behavior with the increasing of gas pressure, and its changes take place mainly in the two sheath regions. The cycle-averaged electron pressure heating, electron ohmic heating, electron heating, and electron energy loss are all influenced by the gas pressure. Two peaks of the electron heating appear in the sheath regions and the two peaks become larger and move to electrodes as the gas pressure increases.

关键词： dual frequency gas pressure glow discharge

Super Compact UWB Monopole Antenna for Small IoT Devices

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Computers, Materials & Continua 2022年第11期73卷 2785-2799页

作者： Ahmed Jamal Abdullah Al-Gburi Zahriladha Zakaria Merih Palandoken Imran Mohd Ibrahim A.A.Althuwayb Sarosh Ahmad samir Salem Al-Bawri Department of Electronics and Computer Engineering(FKEKK) Center for Telecommunication Research and Innovation(CeTRI)Universiti Teknikal Malaysia Melaka(UTeM)Durian Tungal76100Malaysia Department of Electrical and Electronics Engineering Izmir Katip Celebi UniversityIzmir35620Turkey Electrical Engineering Department Jouf UniversitySakaka72388AljoufKingdom of Saudi Arabia Universidad Carloa III de Madrid Leganes28911MadridSpain Space Science Centre Climate Change InstituteUniversiti Kebangsaan Malaysia(UKM)Bangi43600Malaysia

This article introduces a novel,ultrawideband(UWB)planar monopole antenna printed on Roger RT/5880 substrate in a compact size for small Internet of Things(IoT)*** total electrical dimensions of the proposed compact UWB antenna are 0.19λo×0.215λo×0.0196λo with the overall physical sizes of 15 mm×17 mm×1.548 mm at the lower resonance frequency of 3.8 *** planar monopole antenna is fed through the linearly tapered microstrip line on a partially structured ground plane to achieve optimum impedance matching for UWB *** proposed compact UWB antenna has an operation bandwidth of 9.53 GHz from 3.026 GHz up to 12.556 GHz at−10 dB return loss with a fractional bandwidth(FBW)of about 122%.The numerically computed and experimentally measured results agree well in between.A detailed time-domain analysis is additionally accomplished to verify the radiation efficiency of the proposed antenna design for the ultra-wideband signal *** fabricated prototype of a compact UWB antenna exhibits an omnidirectional radiation pattern with the low peak measured gain required of 2.55 dBi at 10 GHz and promising radiation efficiency of 90%.The proposed compact planar antenna has technical potential to be utilized in UWB and IoT applications.

关键词： Internet of things(IoT) ultra-wideband(UWB)application compact UWB monopole antenna