Figure 5.

Schematic illustration of a particle that undergoes (a) symmetric deformation and (b) asymmetric deformation. In (b), the position of the anchor point is shifted between the desewlling and swelling stages, denoted as AP _d and AP _s, respectively. The displacement of the front and back edges during its elongation is denoted by $\mathit{\Delta }{\ell }^{+}$ and $\mathit{\Delta }{\ell }^{-}$, respectively.