Figure 3.

Numerical calculation of the spatiotemporal response of a 2D active viscoelastic fluid in response to COLA. (A) Representative calculated nondimensional height (gray) and velocity field (arrows) of the cortex at times 0, 0.02, 0.04, 0.06, 0.08, and 0.68 after COLA by setting the height to zero in the dark region around the red line in the leftmost image (see main text). (B) Effect of variation of α₁ on the spatial velocity profile at 0.5 s after cut. The x component of velocity vectors was averaged along the y direction and within the box indicated by the broken orange line in the second panel of (A). (C–E) Effect of variation of α₂ and α₃ on the time evolution of the half-width of the cut opening, determined by fitting an ellipse to the opening boundary. Note that changing α₁ has a small effect on time evolution of the width of the opening (E). Unless otherwise specified, parameter values are α₁ = 2.0, α₂ = 0.25, and α₃ = 4.5. For (B)–(E), we have dimensionalized time by ${\tau }_a=25\text{s}$ and length by ${\lambda }_c=25\mu \text{m}$.