{HEAD ~ Superconducting operating temperatures} can be provided by {TAIL ~ a cryogenic container} refrigerated by a closed cycle cryogenic refrigerator, a stored cryogen, or in space, a heat sink 
{ HEAD ~ Superconducting operating temperatures } can be provided by { TAIL ~ a cryogenic container } refrigerated by a closed cycle cryogenic refrigerator , a stored cryogen , or in space , a heat sink
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH