An implantable activity detector can detect metabolic stress levels, which can be normalized, such as to identify times of activities such as walking and running or to identify trends such as a decrease in metabolic activity. The method includes assigning an Internet Protocol address to a network monitoring system to establish a communication between the network monitoring system and an Internet Protocol device associated with the Internet Protocol address. A semiconductor structures is also described having an isolation structure formed on a SOI layer of a semiconductor substrate the isolation structure having an oxidized substrate region; and a void region formed on the oxidized substrate region. The present invention also provides methods for making biradicals with a structure of formula as described herein. An apparatus for carrying out the method is also disclosed.