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Infectious Disease Modelling 2024年第2期9卷 329-353页

作者： Mohamed Ladib aziz ouhinou Abdul-aziz Yakubu University of Sultan Moulay Slimane Faculty of Sciences and TechniquesTeam of Mathematics and InteractionsBéni-MellalMorocco Howard University Dept MathWashingtonDC20059USA

We develop a mathematical model to investigate the effect of contact tracing on containing epidemic outbreaks and slowing down the spread of transmissible *** propose a discrete-time epidemic model structured by disease-age which includes general features of contact *** model is fitted to data reported for the early spread of COVID-19 in South Korea,Brazil,and *** calibrated values for the contact tracing parameters reflect the order pattern observed in its performance intensity within the three *** the fitted values,we estimate the effective reproduction number R_(e)and investigate its responses to varied control scenarios of contact *** the positivity of solutions,and a stability analysis of the disease-free equilibrium are provided.

关键词： Mathematical modeling Infectious diseases Discrete systems Disease-age structured populations Contact tracing Effective reproduction number COVID-19

Two paths, one goal: mechanism of calcium homeostasis to balance plant growth and immunity

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Science China Life Sciences 2025年第1期 306-308页

作者： aziz Ul Ikram Yanping Jing Huan Chen Jian Chen International Genome Center Jiangsu University Joint Center for Single Cell Biology School of Agriculture and BiologyShanghai Jiao Tong University

Calcium(Ca2+) is an essential nutrient and a cellular signal in plants. The level of free Ca2+in the apoplast is ～10,000-fold higher than that in the cytoplasm at the resting state. This large Ca2+level gradient across the membrane between the interior and exterior can cause Ca2+overload and toxicity. Plants have evolved mechanisms to export Ca2+out of the cytoplasm or store it in intracellular organelles, such as endoplasmic reticulum（ER）, mitochondria, and vacuole.

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Mathematical modeling and optimal control problems in brain tumor targeted drug delivery strategies

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International Journal of Biomathematics 2017年第4期10卷 235-296页

作者： aziz Belmiloudi Mathematics Research Institute of Rennes (IRMAR) European University of Brittany (UEB) 20 Av. des Buttes de Coesmes CS 14315 35043 Rennes Cedex France

In this paper, we present a mathematical model that describes tumor-normal cells inter- action dynamics focusing on role of drugs in treatment of brain tumors. The goal is to predict distribution and necessary quantity of drugs delivered in drug-therapy by using optimal control framework. The model describes interactions of tumor and normal cells using a system of reactions^diffusion equations involving the drug concentration, tumor cells and normal tissues. The control estimates simultaneously blood perfusion rate, reabsorption rate of drug and drug dosage administered, which affect the effects of brain tumor chemotherapy. First, we develop mathematical framework which mod- els the competition between tumor and normal cells under chemotherapy constraints. Then, existence, uniqueness and regularity of solution of state equations are proved as well as stability results. Afterwards, optimal control problems are formulated in order to minimize the drug delivery and tumor cell burden in different situations. We show existence and uniqueness of optimal solution, and we derive necessary conditions for optimality. Finally, to solve numerically optimal control and optimization problems, we propose and investigate an adjoint multiple-relaxation-time lattice Boltzmann method for a general nonlinear coupled anisotropic convection-diffusion system （which includes the developed model for brain tumor targeted drug delivery system）.

关键词： Optimal control coupled nonlinear reaztion-diffusion equations anisotropicbrain tumor growth diffusion tensor drug delivery chemotherapy real-time monitoringof distribution logistic growth pointwise controllers adjoint system population dyna-mics magnetic resonance imaging (MRI) convection-enhanced delivery (CED) adjointmultiple-relaxation-time lattice Boltzmann method multiscale Chapman-Enskog expan-sion optimization of therapies.

Fabrication of novel ZnO/MnWO_4 nanocomposites with p-n heterojunction: Visible-light-induced photocatalysts with substantially improved activity and durability

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Journal of Materials Science & Technology 2018年第10期34卷 1891-1901页

作者： Mahsa Pirhashemi aziz Habibi-Yangjeh Department of Chemistry Faculty of Science University of Mohaghegh Ardabili P.O. Box 179 Ardabil Iran

We report, for the first time, binary ZnO/MnW04 nanocomposites with p-n heterojunction fabricated by a simple ultrasonic-calcination route. The phase structure, morphology, and optical along with tex- tural properties were comprehensively characterized. The photocatalytic performance was studied via degradations of rhodamine B, methyl blue and methyl orange （RhB, MB, MO）, and fuchsine pollutants under visible-light illumination. The ZnO/MnW04 nanocomposites exhibited better photocatalytic per-formance than their single components and the nanocomposite with 30 wt% MnW04 showed the highest activity. Photocatalytic performance of this nanocomposite is 22.5, 17.7, 26.8, and 23.9 times higher than that of the ZnO sample in degradations of RhB, MB, MO, and fuchsine dyes, respectively. The improved photocatalytic performance was ascribed to the formation ofp-n heterojunction between ZnO and MnW04 with high charge separation efficiency as well as strong visible-light absorption ability. The possible mechanism for the improved photocatalytic performance was proposed. This study revealed that the novel ZnO/MnW04 p-n heterojunction can act as a promising visible-light-active photocatalyst for environmental applications.

关键词： ZnO/MnW04 p-n heterojunction Visible-light-active Photocatalyst

Numerical Simulation of Dual-Phase-Lag Model and Inverse Fractional Single-Phase-Lag Problem for the Non-Fourier Heat Conduction in a Straight Fin

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Journal of Thermal Science 2020年第3期29卷 632-646页

作者： MOZAFARIFARD Milad AZIMI aziz MEHRZAD Salem Department of Mechanical Engineering Shahid Chamran University of AhvazAhvaz ***Iran

In recent years,many studies have been done on heat transfer in the fin under unsteady boundary conditions using Fourier and non-Fourier *** this paper,unsteady non-Fourier heat transfer in a straight fin having an internal heat source under periodic temperature at the base was investigated by solving numerically Dual-Phase-Lag and Fractional Single-Phase-Lag *** this way,the governing equations of these models were presented for heat conduction analysis in the fin,and their results of the temperature distribution were validated using the theoretical results of Single and Dual-Phase-Lag *** that,for the first time the order of fractional derivation and heat flux relaxation time of the fractional model were obtained for the straight fin problem under periodic temperature at the base using Levenberg-Marquardt parameter estimation *** solve the inverse fractional heat conduction problem,the numerical results of Dual-Phase-Lag model were used as the *** results obtained from Fractional Single-Phase-Lag model could predict the fin temperature distribution at unsteady boundary condition at the base as well as the Dual-Phase-Lag model could.

关键词： non-Fourier heat transfer fractional calculus inverse heat transfer Levenberg-Marquardt straight fin unsteady boundary condition

Designing Bayesian Two-Sided Group Chain Sampling Plan for Gamma Prior Distribution

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Computer Systems Science & Engineering 2023年第2期44卷 1069-1079页

作者： Waqar Hafeez Nazrina aziz School of Quantitative of Sciences Universiti Utara MalaysiaSintok06010Malaysia Institute of Strategic Industrial Decision Modelling(ISIDM) Universiti Utara MalaysiaSintok06010Malaysia

Acceptance sampling is used to decide either the whole lot will be accepted or rejected,based on inspection of randomly sampled items from the same *** an alternative to traditional sampling plans,it is possible to use Baye-sian approaches using previous knowledge on process *** study pre-sents a Bayesian two-sided group chain sampling plan(BTSGChSP)by using various combinations of design *** BTSGChSP,inspection is based on preceding as well as succeeding *** function is used to derive the probability of lot acceptance based on defective and non-defective *** distribution is considered as a suitable prior for Poisson *** quality regions are found,namely:(i)quality decision region(QDR),(ii)probabil-istic quality region(PQR),(iii)limiting quality region(LQR)and(iv)indifference quality region(IQR).Producer’s risk and consumer’s risk are considered to esti-mate the quality regions,where acceptable quality level(AQL)is associated with producer’s risk and limiting quality level(LQL)is associated with consumer’s ***,AQL and LQL are used in the selection of design parameters for *** values based on all possible combinations of design parameters for BTSGChSP are presented and inﬂection points’values are ***ﬁnding exposes that BTSGChSP is a better substitute for the existing plan for industrial practitioners.

关键词： Bayesian acceptance sampling poisson distribution gamma distribution producer’s risk consumer’s risk

Analytical Solution for Time-dependent Flow of a Third Grade Fluid Induced Due to Impulsive Motion of a Flat Porous Plate

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Acta Mathematicae Applicatae Sinica 2015年第3期31卷 757-766页

作者： Taha aziz F.M.Mahomed Azeem Shahzad Asim aziz School of Computational and Applied Mathematics DST-NRF Centre of Excellence in Mathematical and Statistical Sciences Differential Equations Continuum Mechanics and Applications University of the Witwatersrand School of Natural Sciences National University of Sciences and Technology Department of Mathematics Quaid-i-Azam University Department of Basic Sciences and Humanities National University of Sciences and Technology College of Electrical and Mechanical Engineering

The aim of the present communication is to discuss the analytical solution for the unsteady flow of a third grade fluid which occupies the space y 〉 0 over an infinite porous plate. The flow is generated due to the motion of the plate in its own plane with an impulsive velocity V（t）. Translational symmetries in variables t and y are utilized to reduce the governing non-linear partial differential equation into an ordinary differential equation. The reduced problem is then solved using homotopy analysis method（HAM）. Graphs representing the solution are plotted and discussed and proper conclusions are drawn.

关键词： third grade fluid Porous plate translational symmetries Homotopy analysis method(HAM)

Erosion and runoff reduction potential of vetiver grass for hill slopes:A physical model study

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International Journal of Sediment Research 2023年第1期38卷 49-65页

作者： Shamontee aziz Mohammad Shariful Islam BUET-Japan Institute of Disaster Prevention and Urban Safety (BUET-JIDPUS) Bangladesh University of Engineering and Technology (BUET) Department of Civil Engineering Bangladesh University of Engineering and Technology (BUET)

Severe erosion is caused by intense rainfall in tropical regions. The erodible soil of steep hill slopes,accompanied by destruction of vegetation due to human interventions results in accelerated erosion. A sustainable and cost-effective solution such as vetiver grass(Chrysopogon zizanioides) is, thus, required to control the erosion process. In the current study, 6 small-scale glass models: 1 bare and 5 with vetiver grass, having a slope angle of 37°have been constructed. One year after planting, artificial rainfall of extremely high intensity was applied to all 6 small models and the role of vetiver canopy and roots in erosion and runoff control was observed. To see the effect of soil texture, one among these 5 models was made with silty sand and others contained sandy silt. The results demonstrated that, for sandy silt, the inclusion of vetiver reduced the soil loss by 94%-97%, and soil detachment rates were lowered by 95%.The average runoff also was reduced by 21%. The canopy cover showed a positive impact on reducing both quantities. An increase in average root diameter from 1.6 to 2.5 mm increases the soil loss due to its negative impact on added cohesion. The added cohesion showed a linearly negative correlation with soil loss. A composite system of vetiver and jute geotextile was most effective in erosion reduction among 4vegetated models with sandy silt. Under same vetiver planting layout, the grass covered model of silty sand yielded 84% lower erosion and 62.5% lower runoff than the grass covered one with sandy silt. Thus,vetiver was more effective in erosion and runoff reduction for soil with a greater percentage of sand, and soil type dominated the erosion process.

关键词： Erosion Small-scale model experiments Surface runoff Artificial rainfall Vetiver

Corrosion Inhibition of SiCp/5A06 Aluminum Metal Matrix Composite by Cerium Conversion Treatment

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Chinese Journal of Aeronautics 2009年第6期22卷 670-676页

作者： Irfan aziz Zhang Qi Xiang Min School of Materials Science and Engineering Beo'ing University of Aeronautics and Astronautics Beijing 100191 China

This article studies the effects of the CeCl3 concentrations in conversion solutions with and without addition of NaCl, pH-values of conversion solution, drying temperature, time and temperature of immersion on the Ce-conversion coatings for corrosion protection of the SiCp/5A06 Al-MMC and 5A06 Al-alloy in the 3.5% NaCl aqueous solution at room temperature. Potentiodynamic polarization tests reveal that the Ce-conversion treatment could markedly improve the pitting corrosion resistance of the composite and the matrix alloy in chloride containing environment. The best corrosion resistance effects are obtained for the samples treatment in 1% CeCl3.7H2O/3.5% NaCl solution at 45℃ for 60 min, followed by drying at 100 ℃ for 30 min. Examinations by means of scanning electron microscopy （SEM）, energy dispersion spectroscopy （EDS） and X-ray photoelectron spectroscopy （XPS） indicate that this behavior is due to the precipitation of Ce-oxides/hydroxides on the cathodic intermetallics and the Al-oxide film on the rest of the metal matrix.

关键词： cerium thermal coatings SiCp/5A06 Al matrix composites potentiodynamic polarization alkaline corrosion

Zonal distribution and population biology of Ilyoplax frater (Brachyura:Ocypodoidea:Dotillidae) in a coastal mudflat of Pakistan

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Current Zoology 2010年第2期56卷 244-251页

作者： Noor Us SAHER Naureen aziz QURESHI Centre of Excellence in Marine Biology University of Karachi Department of Fisheries and Aquaculture University of Veterinary and Animal Sciences

Zonal distribution and population biology of llyoplaxfrater were studied in a mangrove mudflat area of Pakistan. The crabs were collected from Korangi creek through transect and quadrat method from low tide level to high tide level. Two transects were delimited in a mangrove area of Korangi creek （24°79′N/67°20′E）. On each transect, three 0.25 m quadrats were sampled at three tidal levels on a monthly basis during low tide periods from March 2001 to February 2002. A total of 1124 crabs were obtained, of which 482 were males and 642 were females. Density of crabs varied between 0 and 90/m^2. The density and size distribution varied and showed significant differences from low to high tide level, and were positively correlated with the percent moisture, percent organic matter and sediment grain size. The carapace width （CW） ranged from 2.5 to 11.5 mm for male and 2.5 to 11.0 mm for female and was not significantly different. The overall sex ratio did not differ significantly from the expected 1：1 throughout the year in small crabs but was significantly different in adult crabs （Z2 = 49.73） with more male crabs, Size frequency distribution showed recruitment of juvenile crabs （〈 4 mm） nearly throughout the year except during June and July. Presence of ovigerous females in all months with seasonal peaks in September, October, December and May indicates seasonal continuous breeding. Weight of egg mass increases with weight of ovigerous females and show positive linear relationship. The estimated mean diameter of egg was 2.83±0.25μm, and the average number of eggs was 3065±902.

关键词： Ilyoplaxfrater Population biology Zonal distribution Sex ratio Fecundity Korangi creek Pakistan