A sealer for a sample testing instrument is disclosed that cuts and seals a fluid conduit that connects a test sample device with a fluid receptacle containing a fluid sample. The blades are formed such that attachment of a blade to the trowel arm is achieved by simply attaching the blade using one or more threaded bolts. A second light source acts directly on living biological entities to sterilize or kill them and thereby disinfect the fluid, and can also serve to activate a semiconductor photocatalyst that in turn causes further damage to biological contaminants. The first promoter material includes a first promoter metal andor a compound of a first promoter metal. A caching mechanism may be configured to make it likely that software components referenced by software power sets are loaded into powered storage types during associated intermittent computing sub-states.