Figure 1.

Simplified schematics and glossary of terms used for defining mechanical properties of a deformable biological viscoelastic material (A) with a defined area A, initial length L0 and width W0 under applied shear force $\overrightarrow{F}$ undergoing sample elongation ΔL along the direction of the shear (B). The same deformable viscoelastic material can be either stretched (ie, material undergoes elongation) (C) or compressed (ie, material undergoes deformation) under the application of external force $\overrightarrow{F}$ perpendicular to the surface area A, resulting in changes in length Ln and width Wn, thereby allowing determination of several mechanical parameters including the Young’s modulus E. (Figure 1 was adapted and modified from Wu et al.11)