Figure 6

(a) Solutions of system (9)–(10) with gamma-distributed parameters β on [2, ∞) and δ on [0.9, ∞). Uninfected cells, X(t), infected cells, Y(t), and the total tumor load, X(t) + Y(t), are shown in blue, green and black, respectively. The initial means of distributions are E _β (0) = 11 and E _δ (0) = 10, initial variances are ${\sigma }_{\beta }^2$ (0) = 8 and ${\sigma }_{\delta }^2$ (0) = 0.5. The initial conditions X(0) = 0.5, Y(0) = 0.1 and γ = 0.7. (b) The parametric curve (E _β (t), E _δ (t)) in the parameter space