FIG. 8.

Constructing a closed loop trajectory using C = 0 and C = 0.5, with C_avg = 0.366. (a) By using segments of a trajectory for C = 0 and C = 0.5, switching values at points A and B, we construct a closed periodic orbit. (b) Using the same total dose, we show the MTD and LDM trajectories starting from point A. Both eventually move to the S corner, although initially the MTD trajectory moves toward the H corner (tumor regression) before recurrance. (c) The MTD, LDM, and adaptive schedules are depicted. (d) We plot the average fitness $\langle f\rangle$ for the three different chemo-schedules. The adaptive schedule is able to maintain a higher average fitness throughout.