Existence and global attractivity of unique positive periodic solution for a model of hematopoiesis

In this paper, we consider the generalized model of hematopoiesis x (t)=−a(t)x(t) + m i=1 bi (t) 1+xn(t −τi (t)) . By using a fixed point theorem, some criteria are established for the existence of the unique positive ω- periodic solution ˜x of the above equation. In particular, we not only give the conclusion of convergence of xk to ˜x, where {xk} is a successive sequence, but also show that ˜x is a global attractor of all other positive solutions. © 2006 Elsevier Inc. All rights reserved