A pacing system computes optimal cardiac resynchronization pacing parameters using intrinsic conduction intervals. In one embodiment, the lower portion of the buffer layer is compositional graded AlGaInAs and the upper portion is compositional graded AlInAs. When a packet of data including a task to be handled is received at the adapter, based on the capability registered earlier for the device, the adapter may determine whether to assign the task to the device. The present multi-bit addressing technique allows, for example, 10 to 100 bits of data to be accessed or addressed at a single node. Such compounds are also useful in drug development for non-peptide mimics of the compounds described herein and in the development of therapeutic or diagnostic antibodies. The compositions thereof are useful for treating or relieving pain-related conditions.