According to an embodiment, a pattern classifier device includes a decision unit, an execution unit, a calculator, and a determination unit. In a preferred embodiment, the nucleoside is L-FMAU, or a pharmaceutically acceptable salt or prodrug thereof. A seat 18, 56 supported on the port closure member receives a plug to shift the port closure member to the open port position, wherein the port 32, 56 exposes increased fluid pressure to the piston 24, 58, 70 to move to an activated position.