The samples are compressed in normal direction up to 20%
strain. Each sample is compressed only once at a loading rate
of v ¼ 0.000625, 0.00625, 0.0625, 0.315 and 0.625 mm/s and the
force response is recorded as a function of displacement. The
compression experiments are repeated 4 times at each load-
ing rate with a different sample (see Table 1). Hence, a total of
60 tissue samples are examined in compression (4 samples
per loading rate  5 loading rates per liver  3 livers).