Before revision:  In this experiment, the average spacing between adjacent actin rings, as well as the variance of the spacing, are measured. In this paper, we model the spectrins in this actin-spectrin network as worm-like chains(WLCs), which are stretched to lengths close to their contour lengths. The result attained shows that the observed variance in the separation between actin rings is consistent with the thermal fluctuation of spectrins predicted by the WLC model .
After revision:  In this experiment, the end-to-end distance projected to the force direction .