Chaos in a Tumor Growth Model with Delayed Responses of the Immune System

A simple prey-predator-type model for the growth of tumor with discrete time delay in the immune system is considered. It is assumed that the resting and hunting cells make the immune system. The present model modifies the model of El-Gohary (2008) in that it allows delay effects in the growth proc...

Full description

Saved in:
Bibliographic Details
Main Authors: M. Saleem, Tanuja Agrawal
Format: Article
Language:English
Published: Wiley 2012-01-01
Series:Journal of Applied Mathematics
Online Access:http://dx.doi.org/10.1155/2012/891095
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849401534160306176
author M. Saleem
Tanuja Agrawal
author_facet M. Saleem
Tanuja Agrawal
author_sort M. Saleem
collection DOAJ
description A simple prey-predator-type model for the growth of tumor with discrete time delay in the immune system is considered. It is assumed that the resting and hunting cells make the immune system. The present model modifies the model of El-Gohary (2008) in that it allows delay effects in the growth process of the hunting cells. Qualitative and numerical analyses for the stability of equilibriums of the model are presented. Length of the time delay that preserves stability is given. It is found that small delays guarantee stability at the equilibrium level (stable focus) but the delays greater than a critical value may produce periodic solutions through Hopf bifurcation and larger delays may even lead to chaotic attractors. Implications of these results are discussed.
format Article
id doaj-art-8ccaff6faff0433f80ebab288dc9844f
institution Kabale University
issn 1110-757X
1687-0042
language English
publishDate 2012-01-01
publisher Wiley
record_format Article
series Journal of Applied Mathematics
spelling doaj-art-8ccaff6faff0433f80ebab288dc9844f2025-08-20T03:37:44ZengWileyJournal of Applied Mathematics1110-757X1687-00422012-01-01201210.1155/2012/891095891095Chaos in a Tumor Growth Model with Delayed Responses of the Immune SystemM. Saleem0Tanuja Agrawal1Department of Applied Mathematics, Z. H. College of Engineering & Technology, A.M.U, Aligarh 202002, IndiaDepartment of Applied Mathematics, Z. H. College of Engineering & Technology, A.M.U, Aligarh 202002, IndiaA simple prey-predator-type model for the growth of tumor with discrete time delay in the immune system is considered. It is assumed that the resting and hunting cells make the immune system. The present model modifies the model of El-Gohary (2008) in that it allows delay effects in the growth process of the hunting cells. Qualitative and numerical analyses for the stability of equilibriums of the model are presented. Length of the time delay that preserves stability is given. It is found that small delays guarantee stability at the equilibrium level (stable focus) but the delays greater than a critical value may produce periodic solutions through Hopf bifurcation and larger delays may even lead to chaotic attractors. Implications of these results are discussed.http://dx.doi.org/10.1155/2012/891095
spellingShingle M. Saleem
Tanuja Agrawal
Chaos in a Tumor Growth Model with Delayed Responses of the Immune System
Journal of Applied Mathematics
title Chaos in a Tumor Growth Model with Delayed Responses of the Immune System
title_full Chaos in a Tumor Growth Model with Delayed Responses of the Immune System
title_fullStr Chaos in a Tumor Growth Model with Delayed Responses of the Immune System
title_full_unstemmed Chaos in a Tumor Growth Model with Delayed Responses of the Immune System
title_short Chaos in a Tumor Growth Model with Delayed Responses of the Immune System
title_sort chaos in a tumor growth model with delayed responses of the immune system
url http://dx.doi.org/10.1155/2012/891095
work_keys_str_mv AT msaleem chaosinatumorgrowthmodelwithdelayedresponsesoftheimmunesystem
AT tanujaagrawal chaosinatumorgrowthmodelwithdelayedresponsesoftheimmunesystem