3138
Monitored resistance and stress changed as a function of strain exhibiting hysteresis with more prominent residual strain during stretching and compression cycles and 3-point bending flexural tests of PA and CoPA substrates .
 resistance, stress, as, strain, hysteresis, residual, compression, bending, PA
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
Answer:
 resistance, stress, as, strain, hysteresis, residual, compression, bending, PA