Figure 5.

Comparison of viscoelastic properties of collagen-fibril specimens obtained in three tests, including the elastic modulus (a), and the relaxation time (b). The percentage difference of tests X&Y is equal to $\text{testY}-\text{testX}/\text{testX}\times 100\%$, where X&Y could be 1&2, 1&3, or 2&3. The standard derivation is indicated by the error bar. A paired Student's t-test showed that the elastic moduli obtained in tests 2 and 3 were significantly lower (^∗p < 0.001) than those obtained in test 1, whereas no significant difference was found between the elastic moduli obtained in tests 2 and 3. Furthermore, there was no statistically significant difference in the relaxation time among the three tests.