{HEAD ~ The administrator database} and the one or more investigator databases are communicatively connected to {TAIL ~ the centralized secure database} 
{ HEAD ~ The administrator database } and the one or more investigator databases are communicatively connected to { TAIL ~ the centralized secure database }
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL