Disclosed are working fluid compositions for heat transfer apparatuses, such as refrigeration systems, that include a refrigerant and an ester based lubricant. This logic split permits increased throughput because pending snoop queries must no longer wait until snoop actions complete. The database pool module may be for selectively connecting the processing threads to corresponding database modules including respective user data for jobs to be processed, and determining when a database module becomes unresponsive and terminating processing thread connections to the unresponsive database module based thereon. The methods of the invention are amenable to the large-scale synthesis and purification of oligonucleotides. An actuator is connected to the lower support structure.