For example, a first one of {TAIL ~ the conducting layers} may be comprised of {HEAD ~ a first material} and a second material 
For example , a first one of { TAIL ~ the conducting layers } may be comprised of { HEAD ~ a first material } and a second material
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH