Degenerated Bogdanov-Takens bifurcations in an immuno-tumor model
DOI:
https://doi.org/10.1478/C1A0901005Abstract
A mathematical immuno-tumor model proposed by A. Kavaliauskas [Nonlinear Anal. Model. Control 8, 55 (2003)] and consisting of a Cauchy problem for a system of two first-order ordinary differential equations is studied. For some particular parameters values, this model has saddle-node, Hopf and Bogdanov-Takens (BT) singularities. In the case of the BT singularities, we herein derive the normal forms of the governing equations by using ideas and a method from S.-N. Chow, C. Li, and D. Wang [Normal forms and bifurcation of planar vector fields (1994)] and Yu. A. Kuznetsov [Elements of applied bifurcation theory (1994)], based on an appropriate splitting of associated Hilbert spaces. It is found that a limit case of parameters associated with medicine administration corresponds to degenerate BT bifurcations and, so, to a large variety of responses to the medical treatments for admissible parameters near the limit ones.Downloads
Published
2009-11-26
Issue
Section
Articles
License

This work is licensed under a Creative Commons Attribution 4.0 International License.
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).