The radius of the colony does not allow us to uniquely estimate D and q . All results correspond to experiments where the cells were pretreated with Mitomycin–C to prevent cell proliferation. Images in (A–B), show the entire cell colony for experiments initialised with 30,000 cells at t=0 and t=48 hours, respectively. The scale bar corresponds to 1.5 mm. An equivalent model simulation of the experiment is shown in (E–F), using D=243μ m2hour−1, q=0 and λ=0hour−1. For all images in (A–D), the detected location of the leading edge using the image analysis software is shown in black, while the red circle corresponds to the equivalent circle with the same area as enclosed by the leading edge. Results in (C) and (D) show the time evolution of the average radius of the expanding colony detected in the experiments. The error bars correspond to one standard deviation from the mean (black). Corresponding model simulations which match the experimental results are superimposed (colour lines). Simulation results were averaged over three identically–prepared realisations using three different combinations of parameters which are shown by the coloured crosses on the error surfaces in (G) and (H). The model simulations in (C–D) were generated using D=162μ m2hour−1 and q=0 (red), D=162μ m2hour−1 and q=0.3 (blue) and D=1215μ m2hour−1 and q=0.8 (green), while solutions in (D), were generated using D=81μ m2hour−1 and q=0 (red), D=243μ m2hour−1 and q=0.5 (blue), and D=1215μ m2hour−1 and q=0.8 (green), respectively. The error surfaces in (G) and (H) show Error
(D,q), given by Equation 3, for various values of D and q. The error surfaces were by averaging the radius estimates from three experimental replicates and three identically–prepared model realisations.