The present invention provides methods, compositions, substrates, and kits useful for analyzing the metabolic activity in cells, tissue, and animals and for screening test compounds for their effect on cytochrome P450 activity. A codeword that represents at least a first message of a first information type and a second message of a second information type is received. The system includes a battery charger circuit, a voltage regulator circuit, and a voltage tracking circuit. A second submodel is based on reaction kinetics of cell metabolism and is operatively coupled with the first submodel. In accordance with the illustrative embodiment of the present invention, a plurality of gas-uptake ducts are arranged on a boundary that surrounds a missile, thereby providing a barrier to the propagation of blast energy andor fragments across the boundary.