Fig. 3.

Theoretical modeling of straining the hierarchical helix scaffold. (A) Simulated results show the local strain of the hierarchical helix scaffold under an applied 50% engineering strain, showing that the local material strain is much smaller than the applied engineering strain. (B) The field of local material strains on the helix scaffold and primary yarn under the same engineering strains, showing a much larger local material strain on the primary yarn compared with the helix scaffold. (C) The simulated correlations between local strain and engineering strain show that the local strains on the helix scaffold are much smaller than those on the primary yarn under the same engineering strain. Experimental measurements of cell elongation also fit well with the simulated local material strain of the helix scaffold. (D) Local orientations of seeded cells on the helix scaffolds are consistent with simulated local orientations of nanofibers under the same engineering strain.