A memory system includes a volatile first storing unit, a nonvolatile second storing unit, and a controller. Such enriched populations are useful for studies of the molecular events that occur during differentiation and for generating cells for cell replacement therapy. A plunger reciprocably moves between the stop and the seat to open and close the controlled outlet through the operation of a solenoid assembly. The word items are then processed according to a number of factors, including part-of-speech, entries in dictionaries and thesaurus and other factors. This avoids altering the transient AC characteristics of the memory cell when predicting its performance.