Figure 2. Features of Stress-Strain Behavior Captured by the VAA.

The black curve shows σ₁₁ vs. λ_a from a sample test using 5 mg/mL fibrinogen. The gray curve is a scaled form of the second derivative of the σ₁₁ with respect to λ_a. Points A and B indicate the yield stress and yield stretch, respectively. The ultimate tensile strength (UTS) and ultimate stretch are noted by points C and D, respectively. The linear portion of the black stress-strain curve is estimated by a dotted gray line. The slope of this line is the tangent modulus.