Definition. 1  Troponins are specific proteins found in heart muscle. Troponin testing is done to diagnose heart attacks (myocardial infarctions). 2  When heart muscle is damaged, as in a myocardial infarction (MI), troponins leak out of cells and into the bloodstream.
Variable Ratio Schedule (VR) This is going to be a little confusing at first, but hang on and it will become clear. A variable ratio schedule (VR) is a type of operant conditioning reinforcement schedule in which reinforcement is given after an unpredictable (variable) number of responses are made by the organism. This is almost identical to a Fixed-Ratio Schedule but the reinforcements are given on a variable or changing schedule.
GDC News and Information Blog. 1  VRDC Fall is happening this September, and the call for talks is open! posted Mar 23 2017. 2  GDC 2017 talks are now available to watch via the GDC Vault! posted Mar 14 2017. 3  GDC wraps up another great show and announces 2018 dates. posted Mar 13 2017.  Overwatch nets Game of the Year at 2017 Game Developers Choice Awards.