14781
After the last self - administration session , rats were moved to polycarbonate cages for a 10 - day abstinence period where they either had access to a locked or unlocked running wheel for 2 h / day .
 Chemical: polycarbonate
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: polycarbonate 
Answer:
 Chemical: polycarbonate