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Articles 61 - 90 of 105
Full-Text Articles in Life Sciences
Mathematical Modeling Of Two-Dimensional Unsteady Flow In Growing Tumor, N. Gracia, D. N. Riahi, R. Roy
Mathematical Modeling Of Two-Dimensional Unsteady Flow In Growing Tumor, N. Gracia, D. N. Riahi, R. Roy
Applications and Applied Mathematics: An International Journal (AAM)
We investigate the problem of unsteady fluid flow in growing solid tumors. We develop a mathematical model for a growing tumor whose boundary is taken as a sphere, and the unsteady fluid flow within the tumor is assumed to be two dimensional with respect to the radial distance and the latitudinal angle in spherical coordinates. The expressions for the time, radial and latitudinal variations of the flow velocity, pressure, and the two investigated drug concentrations within the tumor were determined analytically. We calculated these quantities in the tumor as well as in a corresponding normal tissue. We find, in particular, …
On The Stability Of A Three Species Syn-Eco-System With Mortality Rate For The Third Species, B. H. Prasad
On The Stability Of A Three Species Syn-Eco-System With Mortality Rate For The Third Species, B. H. Prasad
Applications and Applied Mathematics: An International Journal (AAM)
The system comprises of a commensal (S1) common to two hosts S2 and S3 with mortality rate for the host (S3). Here all the three species posses limited resources. The model equations constitute a set of three first order non-linear simultaneous coupled differential equations. Criteria for the asymptotic stability of all the eight equilibrium states are established. Trajectories of the perturbations over the equilibrium states are illustrated. Further the global stability of the system is established with the aid of suitably constructed Liapunov’s function and the numerical solutions for the growth rate equations are …
Mathematical Model: Comparative Study Of Thermal Effects Of Laser In Corneal Refractive Surgeries, Gokul Kc, Dil B. Gurung, Pushpa R. Adhikary
Mathematical Model: Comparative Study Of Thermal Effects Of Laser In Corneal Refractive Surgeries, Gokul Kc, Dil B. Gurung, Pushpa R. Adhikary
Applications and Applied Mathematics: An International Journal (AAM)
Lasers have been widely used in ophthalmology. Refractive errors are some of the most common ophthalmic abnormalities worldwide. Laser refractive surgery was developed to correct refractive errors myopia, hyperopia and astigmatism. Two types of laser surgical techniques: lamellar and thermal are available to reshape the corneal curvature. Ultraviolet (UV) emitting argon fluoride (ArF) excimer laser is used to sculpt cornea in lamellar procedures, whereas, infrared (IR) emitting holmium yttrium aluminum garnet (Ho: YAG) laser is used to shrink cornea in thermal procedure. Tissue heating is common in all types of laser surgical techniques. Hence, in this paper, a finite element …
Mathematical Modeling And Analysis Of Leukemia: Effect Of External Engineered T Cells Infusion, Manju Agarwal, Archana S. Bhadauria
Mathematical Modeling And Analysis Of Leukemia: Effect Of External Engineered T Cells Infusion, Manju Agarwal, Archana S. Bhadauria
Applications and Applied Mathematics: An International Journal (AAM)
In this paper, a nonlinear model is proposed and analyzed to study the spread of Leukemia by considering the effect of genetically engineered patients T cells to attack cancer cells. The model is governed by four dependent variables namely; naive or susceptible blood cells, infected or dysfunctional blood cells, cancer cells and immune cells. The model is analyzed by using the stability theory of differential equations and numerical simulation. We have observed that the system is stable in the local and global sense if antigenicity rate or rate of stimulation of immune cells is greater than a threshold value dependent …
Long Wavelength Analysis Of A Model For The Geographic Spread Of A Disease, Layachi Hadji
Long Wavelength Analysis Of A Model For The Geographic Spread Of A Disease, Layachi Hadji
Applications and Applied Mathematics: An International Journal (AAM)
We investigate the temporal and spatial evolution of the spread of an infectious disease by performing a long-wavelength analysis of a classical model for the geographic spread of a rabies epidemic in a population of foxes subject to idealized boundary conditions. We consider twodimensional and three-dimensional landscapes consisting of an infinite horizontal strip bounded by two walls a finite distance apart and a horizontal region bounded above and below by horizontal walls, respectively. A nonlinear partial differential evolution Equation for the leading order of infectives is derived. The Equation captures the space and time variations of the spread of the …
An Optimal Harvesting Strategy Of A Three Species Syn-Ecosystem With Commensalism And Stochasticity, M. N. Srinivas, A. Sabarmathi, K. S. Reddy, M. A. S. Srinivas
An Optimal Harvesting Strategy Of A Three Species Syn-Ecosystem With Commensalism And Stochasticity, M. N. Srinivas, A. Sabarmathi, K. S. Reddy, M. A. S. Srinivas
Applications and Applied Mathematics: An International Journal (AAM)
In this paper we have studied the stability of three typical species syn-ecosystem. The system comprises of one commensal S1 and two hosts S2 and S3 . Both S2 and S2 benefit S1 without getting themselves affected either positively or adversely. Further S2 is a commensal of S3 and S3 is a host of both S1 and S2. Limited resources have been considered for all the three species in this case. The model equations of the system constitute a set of three first order non-linear ordinary differential equations. …
Modeling The Transmission Dynamics Of Typhoid In Malaria Endemic Settings, Steady Mushayabasa, Claver P. Bhunu, Ngoni A. Mhlanga
Modeling The Transmission Dynamics Of Typhoid In Malaria Endemic Settings, Steady Mushayabasa, Claver P. Bhunu, Ngoni A. Mhlanga
Applications and Applied Mathematics: An International Journal (AAM)
Typhoid and malaria co-infection is a major public health problem in many developing countries. In this paper, a deterministic model for malaria and typhoid co-infection is proposed and analyzed. It has been established that the model exhibits a backward bifurcation phenomenon. Overall, the study reveals that a typhoid outbreak in malaria endemic settings may lead to higher cumulative cases of dually-infected individuals displaying clinical symptoms of both infections than singly-infected individuals displaying clinical symptoms of either malaria or typhoid.
Effect Of Toxic Metal On Root And Shoot Biomass Of A Plant A Mathematical Model, O. P. Misra, Preety Kalra
Effect Of Toxic Metal On Root And Shoot Biomass Of A Plant A Mathematical Model, O. P. Misra, Preety Kalra
Applications and Applied Mathematics: An International Journal (AAM)
In this paper, a mathematical model is proposed to study the impact of toxic metals on plant growth dynamics due to transfer of the toxic metal in plant tissues. In the model, it is assumed that the plant uptakes the metal from the soil through the roots and then it is transfered in the plant tissues and cells by transport mechanisms. It is observed experimently that when toxic (heavy) metals combines with the nutrient they form a complex compound due to which nutrient loses its inherent properties and the natural charaterstics of the nutrient are damaged. It is noticed that …
Dynamics Of Phytoplankton, Zooplankton And Fishery Resource Model, B. Dubey, Atasi Patra, R. K. Upadhyay
Dynamics Of Phytoplankton, Zooplankton And Fishery Resource Model, B. Dubey, Atasi Patra, R. K. Upadhyay
Applications and Applied Mathematics: An International Journal (AAM)
In this paper, a new mathematical model has been proposed and analyzed to study the interaction of phytoplankton- zooplankton-fish population in an aquatic environment with Holloing’s types II, III and IV functional responses. It is assumed that the growth rate of phytoplankton depends upon the constant level of nutrient and the fish population is harvested according to CPUE (catch per unit effort) hypothesis. Biological and bionomical equilibrium of the system has been investigated. Using Pontryagin’s Maximum Principal, the optimal harvesting policy is discussed. Chaotic nature and bifurcation analysis of the model system for a control parameter have been observed through …
Growth Patterns Of Ethnic Groups In Bexar County With Dynamic Leslie Models, Judith Arriaza, Zhanbo Yang, Flor De María García-Wukovits
Growth Patterns Of Ethnic Groups In Bexar County With Dynamic Leslie Models, Judith Arriaza, Zhanbo Yang, Flor De María García-Wukovits
Applications and Applied Mathematics: An International Journal (AAM)
The purpose of this study is to modify the Leslie model with a dynamic matrix for better population projections in Bexar County, where UIW is located and the authors reside. A dynamic matrix was used to improve the static Leslie model used in the previous study since human population growth is dynamic and complex. The matrix was constructed with functions that modeled the birth rates and survival rates. This allowed the rates to change from year to year. The population projections using the dynamic matrix were compared to the real population data and the static matrix. The researcher concluded that …
The Two-Phase Arterial Blood Flow With Or Without A Catheter And In The Presence Of A Single Or Multi Stenosis, Ani E. Garcia, Daniel N. Riahi
The Two-Phase Arterial Blood Flow With Or Without A Catheter And In The Presence Of A Single Or Multi Stenosis, Ani E. Garcia, Daniel N. Riahi
Applications and Applied Mathematics: An International Journal (AAM)
We consider the problem of blood flow in an artery with or without a catheter and in the presence of single or multi stenosis whose shape is based on the available experimental data for the stenosis in a human’s artery. The presence of stenosis in the artery, which locally narrows portion of the artery, can be a result of fatty materials such as cholesterol in the blood. The use of catheter is important as a standard tool for diagnosis and treatment in patience whose blood flow passage in the artery is affected adversely by the presence of the stenosis within …
Numerical Solution Of Fuzzy Arbitrary Order Predator-Prey Equations, Smita Tapaswini, S. Chakraverty
Numerical Solution Of Fuzzy Arbitrary Order Predator-Prey Equations, Smita Tapaswini, S. Chakraverty
Applications and Applied Mathematics: An International Journal (AAM)
This paper seeks to investigate the numerical solution of fuzzy arbitrary order predator-prey equations using the Homotopy Perturbation Method (HPM). Fuzziness in the initial conditions is taken to mean convex normalised fuzzy sets viz. triangular fuzzy number. Comparisons are made between crisp solution given by others and fuzzy solution in special cases. The results obtained are depicted in plots and tables to demonstrate the efficacy and powerfulness of the methodology.
Spread Of Malicious Objects In Computer Network: A Fuzzy Approach, Bimal K. Mishra, Apeksha Prajapati
Spread Of Malicious Objects In Computer Network: A Fuzzy Approach, Bimal K. Mishra, Apeksha Prajapati
Applications and Applied Mathematics: An International Journal (AAM)
We propose an e-epidemic fuzzy SEIQRS (Susceptible-Exposed-Infectious-Quarantine- Recovered-Susceptible) model for the transmission of malicious codes in a computer network. We have simulated the result for various parameters and analyzed the stability of the model. The efficiency of antivirus software and crashing of the nodes due to attack of malicious code is analyzed. Furthermore, initial simulation results illustrate the behavior of different classes for minimizing the infection in a computer network. It also reflects the positive impact of anti-virus software on malicious code propagation in a computer network. The basic reproduction number R0 f and its formulation is also discussed.
Grayscale-Image Encryption Using Random Hill Cipher Over Sln(F) Associated With Discrete Wavelet Transformation, D. C. Mishra, R. K. R. K. Sharma
Grayscale-Image Encryption Using Random Hill Cipher Over Sln(F) Associated With Discrete Wavelet Transformation, D. C. Mishra, R. K. R. K. Sharma
Applications and Applied Mathematics: An International Journal (AAM)
Image data are highly sensitive and prone to incidental decoding by intruders. The security of image data in an insecure network is therefore a major issue. In this paper, we have presented a novel approach for grayscale-image encryption and decryption using Random Hill cipher over SLn(F) associated with discrete wavelet transformation. Earlier techniques for encryption and decryption of image data discussed missing the keys, but in this approach, both the keys and the arrangement of RHC are emphasized. Additionally, keys multiplication side (pre or post) over a grayscale-image data matrix also inevitable to know, to correctly decrypt the encrypted image …
Global Dynamics Of A Water-Borne Disease Model With Multiple Transmission Pathways, Prasanta K. Mondal, T. K. Kar
Global Dynamics Of A Water-Borne Disease Model With Multiple Transmission Pathways, Prasanta K. Mondal, T. K. Kar
Applications and Applied Mathematics: An International Journal (AAM)
We propose and analyze a water born disease model introducing water-to-person and person-toperson transmission and saturated incidence. The disease-free equilibrium and the existence criterion of endemic equilibrium are investigated. Trans critical bifurcation at the disease-free equilibrium is obtained when the basic reproductive number is one. The local stability of both the equilibria is shown and a Lyapunov functional approach is also applied to explore the global stability of the system around the equilibria. We display the effects of pathogen contaminated water and infection through contact on the system dynamics in the absence of person-to-person contact as well as in the …
Effect Of Rising Temperature Due To Ozone Depletion On The Dynamics Of A Prey-Predator System: A Mathematical Model, O. P. Misra, Preety Kalra
Effect Of Rising Temperature Due To Ozone Depletion On The Dynamics Of A Prey-Predator System: A Mathematical Model, O. P. Misra, Preety Kalra
Applications and Applied Mathematics: An International Journal (AAM)
It is well recognized that the greenhouse gas such as Chlorofluoro Carbon (CFC) is responsible directly or indirectly for the increase in the average global temperature of the Earth. The presence of CFC is responsible for the depletion of ozone concentration in the atmosphere due to which the heat accompanied with the sun rays are less absorbed causing increase in the atmospheric temperature of the Earth. The increase in the temperature level directly or indirectly affects the dynamics of interacting species systems. Therefore, in this paper a mathematical model is proposed and analyzed using stability theory to asses the effects …
Modeling The Effect Of Environmental Factors On The Spread Of Bacterial Disease In An Economically Structured Population, Ram Naresh, Surabhi Pandey
Modeling The Effect Of Environmental Factors On The Spread Of Bacterial Disease In An Economically Structured Population, Ram Naresh, Surabhi Pandey
Applications and Applied Mathematics: An International Journal (AAM)
We have proposed and analyzed a nonlinear mathematical model for the spread of bacterial disease in an economically structured population (rich and poor) including the role of vaccination. It is assumed that rich susceptible get infected through direct contact with infectives in the same class and with infectives from the poor class who work as service providers in the houses of rich people, living in much cleaner environment. The susceptible in the poor class are assumed to become infected through direct contact with infectives in the same class as well as by bacteria present in their own environment, degraded due …
A Mathematical Study On The Dynamics Of An Eco-Epidemiological Model In The Presence Of Delay, T. K. Kar, Prasanta K. Mondal
A Mathematical Study On The Dynamics Of An Eco-Epidemiological Model In The Presence Of Delay, T. K. Kar, Prasanta K. Mondal
Applications and Applied Mathematics: An International Journal (AAM)
In the present work a mathematical model of the prey-predator system with disease in the prey is proposed. The basic model is then modified by the introduction of time delay. The stability of the boundary and endemic equilibria are discussed. The stability and bifurcation analysis of the resulting delay differential equation model is studied and ranges of the delay inducing stability as well as the instability for the system are found. Using the normal form theory and center manifold argument, we derive the methodical formulae for determining the bifurcation direction and the stability of the bifurcating periodic solution. Some numerical …
The Principle Of Linearized Stability For Size-Structured Population Models, M. El-Doma
The Principle Of Linearized Stability For Size-Structured Population Models, M. El-Doma
Applications and Applied Mathematics: An International Journal (AAM)
The principle of linearized stability for size-structured population dynamics models is proved giving validity to previous stability results reported in, for example, El-Doma (2008-1). In particular, we show that if all the roots of the characteristic equation lie to the left of the imaginary axis then the steady state is locally exponentially stable, and on the other hand, if there is at least one root that lies to the right of the imaginary axis then the steady state is unstable. We also point out cases when there is resonance
The Dynamics Of Stage Structured Prey-Predator Model Involving Parasitic Infectious Disease, Raid K. Naji, Dina S. Al-Jaf
The Dynamics Of Stage Structured Prey-Predator Model Involving Parasitic Infectious Disease, Raid K. Naji, Dina S. Al-Jaf
Applications and Applied Mathematics: An International Journal (AAM)
In this paper a prey-predator model involving parasitic infectious disease is proposed and analyzed. It is assumed that the life cycle of predator species is divided into two stages immature and mature. The analysis of local and global stability of all possible subsystems is carried out. The dynamical behaviors of the model system around biologically feasible equilibria are studied. The global dynamics of the model are investigated with the help of Suitable Lyapunov functions. Conditions for which the model persists are established. Finally, to nationalize our analytical results, numerical simulations are worked out for a hypothetical set of parameter values.
Modeling Spread Of Polio With The Role Of Vaccination, Manju Agarwal, Archana S. Bhadauria
Modeling Spread Of Polio With The Role Of Vaccination, Manju Agarwal, Archana S. Bhadauria
Applications and Applied Mathematics: An International Journal (AAM)
In this paper, we have proposed and analyzed a nonlinear mathematical model for the spread of Polio in a population with variable size structure including the role of vaccination. A threshold parameter, R , is found that completely determines the stability dynamics and outcome of the disease. It is found that if R 1, the disease free equilibrium is stable and the disease dies out. However, if R >1, there exists a unique endemic equilibrium that is locally asymptotically stable. Conditions for the persistence of the disease are determined by means of Fonda’s theorem. Moreover, numerical simulation of the proposed …
Mathematical Modeling Of Peristaltic Flow Of Chyme In Small Intestine, Daniel N. Riahi, Ranadhir Roy
Mathematical Modeling Of Peristaltic Flow Of Chyme In Small Intestine, Daniel N. Riahi, Ranadhir Roy
Applications and Applied Mathematics: An International Journal (AAM)
Mathematical models based on axisymmetric Newtonian incompressible fluid flow are studied for the peristaltic flow of chyme in the small intestines, which is an axisymmetric cylindrical tube. The flow is modeled more realistically modeled by assuming that the peristaltic rush wave is a non-periodic mode composed of two sinusoidal waves of different wavelengths, which propagate at the same speed along the outer boundary of the tube. Both cases of flow in a tube and in an annulus that are modeled and investigated in the present paper correspond respectively to the cases of flow of chyme in the small intestine in …
A Cellular Automata Model Of Infection Control On Medical Implants, Alicia Prieto-Langarica, Hristo Kojouharov, Benito Chen-Charpentier, Liping Tang
A Cellular Automata Model Of Infection Control On Medical Implants, Alicia Prieto-Langarica, Hristo Kojouharov, Benito Chen-Charpentier, Liping Tang
Applications and Applied Mathematics: An International Journal (AAM)
S. epidermidis infections on medically implanted devices are a common problem in modern medicine due to the abundance of the bacteria. Once inside the body, S. epidermidis gather in communities called biofilms and can become extremely hard to eradicate, causing the patient serious complications. We simulate the complex S. epidermidis-Neutrophils interactions in order to determine the optimum conditions for the immune system to be able to contain the infection and avoid implant rejection. Our cellular automata model can also be used as a tool for determining the optimal amount of antibiotics for combating biofilm formation on medical implants.
Shooting Neural Networks Algorithm For Solving Boundary Value Problems In Odes, Kais I. Ibraheem, Bashir M. Khalaf
Shooting Neural Networks Algorithm For Solving Boundary Value Problems In Odes, Kais I. Ibraheem, Bashir M. Khalaf
Applications and Applied Mathematics: An International Journal (AAM)
The objective of this paper is to use Neural Networks for solving boundary value problems (BVPs) in Ordinary Differential Equations (ODEs). The Neural networks use the principle of Back propagation. Five examples are considered to show effectiveness of using the shooting techniques and neural network for solving the BVPs in ODEs. The convergence properties of the technique, which depend on the convergence of the integration technique and accuracy of the interpolation technique are considered.
Global Stability Of Worms In Computer Network, Bimal Kumar Mishra, Aditya Kumar Singh
Global Stability Of Worms In Computer Network, Bimal Kumar Mishra, Aditya Kumar Singh
Applications and Applied Mathematics: An International Journal (AAM)
An attempt has been made to show the impact of non-linearity of the worms through SIRS (susceptible – infectious – recovered - susceptible) and SEIRS (susceptible – exposed – infectious – recovered - susceptible) e-epidemic models in computer network. A very general form of non-linear incidence rate has been considered satisfying the worm propagating behavior in computer network. The concavity conditions with a non-linear incidence rate and under the constant population size assumption are shown to be stable. Such systems have either a unique and stable endemic equilibrium state or no endemic equilibrium state at all; in the latter case, …
Approximate Approach To The Das Model Of Fractional Logistic Population Growth, S. Das, P. K. Gupta, K. Vishal
Approximate Approach To The Das Model Of Fractional Logistic Population Growth, S. Das, P. K. Gupta, K. Vishal
Applications and Applied Mathematics: An International Journal (AAM)
In this article, the analytical method, Homotopy perturbation method (HPM) has been successfully implemented for solving nonlinear logistic model of fractional order. The fractional derivatives are described in the Caputo sense. Using initial value, the explicit solutions of population size for different particular cases have been derived. Numerical results show that the method is extremely efficient to solve this complicated biological model.
Remarks On The Stability Of Some Size-Structured Population Models V: The Case When The Death Rate Depends On Adults Only And The Growth Rate Depends On Size Only, M. El-Doma
Applications and Applied Mathematics: An International Journal (AAM)
We continue our study of size-structured population dynamics models when the population is divided into adults and juveniles, started in El-Doma (To appear). We concentrate our efforts in the special case when the death rate depends on adults only, the growth rate depends on size only and the maximum size for an individual in the population is infinite. Three demographic parameters are identified and are shown to determine conditions for the (in)stability of a nontrivial steady state. We also give examples that illustrate the stability results. The results in this paper generalize previous results, for example, see Calsina, et al. …
Two-Layered Model Of Blood Flow Through Composite Stenosed Artery, Padma Joshi, Ashutosh Pathak, B. K. Joshi
Two-Layered Model Of Blood Flow Through Composite Stenosed Artery, Padma Joshi, Ashutosh Pathak, B. K. Joshi
Applications and Applied Mathematics: An International Journal (AAM)
In this paper a steady, axisymmetric flow, with a constricted tube has been studied. The artery has been represented by a two-layered model consisting of a core layer and a peripheral layer. It has been shown that the resistance to flow and wall shear stress increases as the peripheral layer viscosity increases. The results are compared graphically with those of previous investigators. It has been observed that the existence of peripheral layer is useful in representation of diseased arterial system.
Remarks On The Stability Of Some Size-Structured Population Models Vi: The Case When The Death Rate Depends On Juveniles Only And The Growth Rate Depends On Size Only And The Case When Both Rates Depend On Size Only, M. El-Doma
Applications and Applied Mathematics: An International Journal (AAM)
We continue our study of size-structured population dynamics models when the population is divided into adults and juveniles, started in El-Doma (to appear 1) and continued in El-Doma (to appear 2). We concentrate our efforts in two special cases, the first is when the death rate depends on juveniles only and the growth rate depends on size only, and, the second is when both the death rate and the growth rate depend on size only. In both special cases we assume that the maximum size for an individual in the population is infinite. We identify three demographic parameters and show …
Remarks On The Stability Of Some Size-Structured Population Models Iv: The General Case Of Juveniles And Adults, M. El-Doma
Applications and Applied Mathematics: An International Journal (AAM)
The stability of some size-structured population dynamics models is investigated when the population is divided into adults and juveniles. We determine the steady states and study their stability. We also give examples that illustrate the stability results. The results in this paper generalize previous results, for example, see Calsina, et al. (2003), El-Doma (2006), Farkas, et al. (2008), and El-Doma (2008 a).