In {TAIL ~ the case} of {HEAD ~ a positive logic signal}, the signal is active high where the logically true state corresponds to a logic level one 
In { TAIL ~ the case } of { HEAD ~ a positive logic signal } , the signal is active high where the logically true state corresponds to a logic level one
OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH