In certain preferred embodiments, {HEAD ~ the molar ration} of :{TAIL ~ A} is in the range of 1:1 to 1:10 
In certain preferred embodiments , { HEAD ~ the molar ration } of : { TAIL ~ A } is in the range of 1:1 to 1:10
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH