A developer carrying member having less environmental dependence is provided. In one example, the system comprises components designed to degrade upon the presence of desired concentrations of proteinases, specifically matrix metalloproteinases, and subsequent release of the agent. The fuel injection controller supplies fuel to the engine through the direct injector and the intake injector when the engine is idling. The embodiments may be implemented using a workbench, which is an analytical tool, implementable by processor software, hardware, or a combination thereof. The drug reservoir is compressible and adapted to contain a drug.