Fig. 9.

Application: migration of cells on a system of electrospun fibers under a VEGF gradient. Cell macroscopic density at time $t=3$ in response to a chemotactic gradient oriented toward the north (as indicated by the arrow) is illustrated in two scenarios: fibers horizontally oriented in the entire domain (a) and fibers vertically oriented in the entire domain (b). The cell sensing radius in both cases is $R=0.7$. The time evolution of the cell mean speed defined in (75) is shown in (c) for the case of perpendicular cues (continuous line that corresponds to scenario (a)) and parallel cues (dashed line that corresponds to scenario (b))(color figure online)