In some embodiments {HEAD ~ the pedestal} also has {TAIL ~ a surrounding shroud} defining an annular pumping passage around the pedestal 
has
In some embodiments { HEAD ~ the pedestal } also has { TAIL ~ a surrounding shroud } defining an annular pumping passage around the pedestal
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH