The disclosed methods and apparatus relate generally to accessing electronic data about persons of interest. The system comprises a filter bank, a control module and a blend module. The terminal apparatus presets a rejection condition for rejecting the reception of present data transmitted from a sender by user setting processing with a present reception rejection processing program. The amplifying device and the signal processing method may be applied in a communication network system. Intravascular indicators are stimulated, and emissions patterns detected for computation of cardiac output, cardiac index, blood volume and other indicators of cardiovascular health.