In particular, {HEAD ~ the current flow} at any point 15 can vary in proportion to {TAIL ~ the stress} at that point 
In particular , { HEAD ~ the current flow } at any point 15 can vary in proportion to { TAIL ~ the stress } at that point
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH