Treatment of Polio Delayed Epidemic Model via Computer Simulations

Through the study,the nonlinear delayed modelling has vital significance in the different field of allied sciences like computational biology,computational chemistry,computational physics,computational economics and many more.Polio is a contagious viral illness that in its most severe form causes nerve injury leading to paralysis,difficulty breathing and sometimes death.In recent years,developing regions like Asia,Africa and sub-continents facing a dreadful situation of poliovirus.That is the reason we focus on the treatment of the polio epidemic model with different delay strategies in this article.Polio delayed epidemic model is categorized into four compartments like susceptible,exposed,infective and vaccinated classes.The equilibria,positivity,boundedness,and reproduction number are investigated.Also,the sensitivity of the parameters is analyzed.Well,known results like the Routh Hurwitz criterion and Lyapunov function stabilities are investigated for polio delayed epidemic model in the sense of local and global respectively.Furthermore,the computer simulations are presented with different traditions in the support of the analytical analysis of the polio delayed epidemic model.

Study Development of the Cardiac Computer Simulations

The technique of computer simulations is a very efficient method in investigating mechanisms of many diseases. This paper reviews how the simulations of the human heart started as a simple mathematical models in the past and developed to the point where genetic information is needed to do suitable work like finding out new medicaments against heart diseases. Also the influence of the development of computer performance in the future as well as the data presentation is described.

Spatio-Temporal Dynamics and Structure Preserving Algorithm for Computer Virus Model

The present work is related to the numerical investigation of the spatio-temporal susceptible-latent-breaking out-recovered(SLBR)epidemic model.It describes the computer virus dynamics with vertical transmission via the internet.In these types of dynamics models,the absolute values of the state variables are the fundamental requirement that must be fulfilled by the numerical design.By taking into account this key property,the positivity preserving algorithm is designed to solve the underlying SLBR system.Since,the state variables associated with the phenomenon,represent the computer nodes,so they must take in absolute.Moreover,the continuous system(SLBR)acquires two steady states i.e.,the virus-free state and the virus existence state.The stability of the numerical design,at the equilibrium points,portrays an exceptional aspect about the propagation of the virus.The designed discretization algorithm sustains the stability of both the steady states.The computer simulations also endorse that the proposed discretization algorithm retains all the traits of the continuous SLBR model with spatial content.The stability and consistency of the proposed algorithm are verified,mathematically.All the facts are also ascertained by numerical simulations.

Theoretical study of elastic, mechanical and thermodynamic properties of MgRh intermetallic compound

In the last years,Magnesium alloys are known to be of great technological importance and high scientific interest.In this work,density functional theory plane-wave pseudo potential method,with local density approximation(LDA)and generalized gradient approximation(GGA)are used to perform first-principles quantum mechanics calculations in order to investigate the structural,elastic and mechanical properties of the intermetallic compound MgRh with a CsCl-type structure.Comparison of the calculated equilibrium lattice constant and experimental data shows good agreement.The elastic constants were determined from a linear fit of the calculated stress-strain function according to Hooke's law.From the elastic constants,the bulk modulus B,shear modulus G,Young's modulus E,Poisson's ratioσ,anisotropy factor A and the ratio B/G for MgRh compound are obtained.The sound velocities and Debye temperature are also predicted from elastic constants.Finally,the linear response method has been used to calculate the thermodynamic properties.The temperature dependence of the enthalpy H,free energy F,entropy S,and heat capacity at constant volume C_(v)of MgRh crystal in a quasi-harmonic approximation have been obtained from phonon density of states and discussed for the first report.This is the first quantitative theoretical prediction of these properties.

Density functional study of elastic,mechanical and thermodynamic properties of MgCu with a CsCl-type structure

We have employed the density functional theory plane-wave pseudo potential method,with local density approximation and generalized gradient approximation to perform first-principles quantum mechanics calculations in order to investigate the structural,elastic and mechanical properties of the intermetallic compound MgCu with a CsCl-type structure.The calculated equilibrium lattice constant is in good agreement with the experimental and theoretical values.The elastic constants were determined from a linear fit of the calculated stress-strain function according to Hooke’s law.From the elastic constants,the bulk modulus B,anisotropy factor A,shear modulus G,Young’s modulus E,Poisson’s ratio y,and the ratio B/G for MgCu compound are obtained.Our calculated results for the bulk modulus B,and Young’s modulus E are consistent with the experimental and theoretical data.The sound velocities and Debye temperature are also predicted from elastic constants.Finally,the linear response method has been used to calculate the thermodynamic properties.The temperature dependence of the enthalpy H,free energy F,entropy S,and heat capacity at constant volume Cv of MgCu crystal in a quasi-harmonic approximation have been obtained from phonon density of states and discussed for the first report.

Milestones of the Modeling of Human Physiology

An overview of about 70-year research efforts in area of mathematical modeling of human physiology is provided.The overview has two goals:(1)to recognize the main advantages and causes of disadvantages or disappointments;(2)to distinguish the most promising approach for creating future models.Until recently,efforts in the modeling of quantitative physiology were concentrated on the solving of three main types of tasks:(1)how to establish the input-output dynamic characteristics of a given isolated organ or isolated anatomical-functional system(AFS);(2)how to create a computer-based simulator of physiological complex systems(PCM)containing many organs and AFSs;and(3)how to create multi-scale models capable of simulating and explaining causalities in organs,AFSs,PCMs,and in the entire organism in terms that will allow using such models for simulating pathological scenarios(the“Physiome”project)too.The critical analysis of the modeling experience and recent physiological concepts convinced us that the platform provided by the paradigm of physiological super-systems(PPS)looks like the most promising platform for further modeling.PPS causally combines activities of specific intracellular mechanisms(self-tunable but of limited capacities)with their extracellular enhancers.The enhancement appears due to the increase of nutrients incomes toward cells affected because of low energy and inadequate chemical composition of cytoplasm.Every enhancer has its activator chemicals released by the affected cells.In fact,PPS,indicating causal relationships between cellscale and upper-scales(in organs,AFSs,PCMs)physiological activities,is the single platform for future models.They must definitely describe when and how the bottom-to-up information flows do appear and how is the organism-scale adaptation activated against destructive trends in cells.

Structural modeling of proteins by integrating small-angle x-ray scattering data

Elucidating the structure of large biomolecules such as multi-domain proteins or protein complexes is challenging due to their high flexibility in solution. Recently, an ＂integrative structural biology＂ approach has been proposed, which aims to determine the protein structure and characterize protein flexibility by combining complementary high- and lowresolution experimental data using computer simulations. Small-angle x-ray scattering（SAXS） is an efficient technique that can yield low-resolution structural information, including protein size and shape. Here, we review computational methods that integrate SAXS with other experimental datasets for structural modeling. Finally, we provide a case study of determination of the structure of a protein complex formed between the tandem SH3 domains in c-Cb1-associated protein and the proline-rich loop in human vinculin.

Dusty Sheaths in Magnetized Plasmas

Parameters of self-consistent magnetized dusty sheaths are investigated usingcomputer simulations of a temporal evolution of one-dimensional slab plasma with dust particles.The evolution is caused by a collection of electrons and ions by both a wall (electrode) and dustparticles, which are initially immersed into plasma and distributed in front of the electrode.Obtained results show the existence of oscillations of a self-consistent potential in magnetizeddusty sheaths including boundary potentials. Dust particles weaken magnetized sheaths and createadditional sheaths close to a boundary of dust particles. The magnetic field does not influence onthe dust particle charge.

Magnetospheric Physics in China

In the past two years,many progresses were made in Magnetospheric Physics by using the data of SuperMAG,Double Star Program,Cluster,THEMIS,RBSP,DMSP,DEMETER,NOAA,Van Allen probe,Swarm,MMS,ARTEMIS,MESSENGER,Fengyun,BeiDa etc.,or by computer simulations.This paper briefly reviews these works based on papers selected from the 248 publications from January 2018 to December 2019.The subjects covered various sub-branches of Magnetospheric Physics,including geomagnetic storm,magnetospheric substorm,magnetic reconnection,solar wind-magnetosphere-ionosphere interaction,radiation belt,ring current,whistler waves,plasmasphere,outer magnetosphere,magnetotail,planetary magnetosphere,and technique.

Windows Influence on Room Daylighting in Residential Buildings

Daylighting studies in buildings are key parts of environmental analysis and can be easily conducted at the early stages of design as part of environmentally responsive building design as well as to inform the final architectural layout and interior design. The main aim of this study is to demonstrate how such daylighting studies can be completed at the early stages of design and, at the same time, to show the impact of window design and positioning on building indoor environments. The paper is focused on a study of window influence on room daylighting in residential buildings and computer lighting simulations in software packages： Windows Daylighting System and Autodesk Ecotect Analysis, have been carried out for different style and positioning of windows using several case studies. The main findings clearly indicated that not only the window size and style matters, but also the positioning of windows considering external walls which would make a significant influence on room daylighting levels and, therefore, such daylight studies are very important for the early stage of environmental analysis during building design.

Effects of Internal Relaxation under Inplane Strain on the Structural,Electronic and Optical Properties of Perovskite BaZrO3

We present the specific ab-initio calculations that detail the variations of perovskite BaZrO3 caused by in-plane strain. Specifically, the internal relaxation, which was not captured in the widely used biaxial strain model, was included in a complementary manner to lattice relaxation. Density functional theory as well as a hybrid functional method based on a plane wave basis set was employed to calculate the lattice structure, elastic constants, electronic properties and optical properties of perovskite BaZrO3. The lattice parameter c exhibited a clear linear dependence on the imposed in-plane strain, but the Poisson＇s ratio caused by internal relaxation was smaller than the elastic deformation, indicating an ＂inelastic＂ or ＂plastic＂ relaxation manner caused by the introduction of internal relaxation. As a result, the related electronic and optical properties of perovskite BaZrO3 were also strongly affected by the in-plane strain, which revealed an effective way to adjust the properties of perovskite BaZrO3 via internal relaxation.

Computational solution of an acid-mediated tumor-growth radial model under logistic growth regimes for normal and cancer cells

Tumor invasion follows a complex mechanism which involves cell migration and proliferation.To study the processes in which primary and secondary metastases invade and damage the normal cells,mathematical models are often extremely useful.In this paper,we present a mathematical model of acid-mediated tumor growth consisting of radially symmetric reaction-diffusion equations.The assumption on the radial symmetry of the solutions is imposed here in view that tumors present spherical symmetry at the microscopic level.Moreover,we consider various empirical mechanisms which describe the propagation of tumors by considering cancer cells,normal cells,and the concentration of H+ions.Among other assumptions,we suppose that these components follow logistictype growth rates.Evidently,this is an important difference with respect to various other mathematical models for tumor growth available in the literature.Moreover,we also add competition terms of normal and tumor cells growth.We carry out a balancing study of the equations of the model,and a numerical model is proposed to produce simulations.Various practical remarks derived from our assumptions are provided in the discussion of our simulations.

A review of advances in tribology in 2020–2021

Around 1,000 peer-reviewed papers were selected from 3,450 articles published during 2020–2021,and reviewed as the representative advances in tribology research worldwide.The survey highlights the development in lubrication,wear and surface engineering,biotribology,high temperature tribology,and computational tribology,providing a show window of the achievements of recent fundamental and application researches in the field of tribology.

Experimental-computational study of fibrous particle transport and deposition in a bifurcating lung model

Experiments carried out using a lung model with a single horizontal bifurcation under different steady inhalation conditions explored the orientation of depositing carbon fibers, and particle deposition frac- tions. The orientations of deposited fibers were obtained from micrographs. Specifically, the effects of the sedimentation parameter （γ）, fiber length, and flow rate on orientations were analyzed. Our results indicate that gravitational effect on deposition cannot be neglected for 0.0228 〈 γ 〈 0.247. The absolute orientation angle of depositing fibers decreased linearly with increasing y for values 0.0228 〈 γ 〈 0.15. Correspondence between Stokes numbers and y suggests these characteristics can be used to estimate fiber deposition in the lower airways. Computer simulations with sphere-equivalent diameter models for the fibers explored deposition efficiency vs. Stokes number. Using the volume-equivalent diameter model, our experimental data for the horizontal bifurcation were replicated. Results for particle deposition using a lung model with a vertical bifurcation indicate that body position also affects deposition.