In the downstream direction, the OLT (usually) continuously transmits (or may burst transmit). CTLA4 transmits an inhibitory signal to T cells, whereas CD28 transmits a stimulatory signal. The test probe transmits and receives microwaves. With wavelength-division multiplexing, each customer transmits their signal using a unique wavelength. The message model defines a standard set of messages that the ESB transmits and receives. Each antenna transmits a narrow beam. Vomiting, in particular, transmits infection effectively and appears to allow airborne transmission. The Dexcom G4 transmits via radio frequency and requires a dedicated receiver. The device then transmits mileage data to servers. This means that the node that transmits the first 1 loses arbitration. The chip then transmits its data back through the coil to the scanner. The base station transmits correction data to the rover. It also transmits various digital television channels. Anticholinergic drugs block the action of acetylcholine, which transmits messages in the nervous system. The TFC transmits and absorbs compressive forces.