A method and system for contextual messaging as utilized for decision support is disclosed. The available resources of a transmission medium can be apportioned between subscribers receiving data through the transmission medium and the resources apportioned to a subscriber can be allocated to different data flows by giving priority to low-latency data packets over normal-latency data packets. The gate structure is disposed on the semiconductor substrate within the gate region. A pair of compressive dampers is mounted in the housing between the flexural disk and the housing end plates. Multiple \u201ccorrect\u201d answers are integrated into the learning system to allow individual learning experiences in which navigation through the system is at a pace controlled by the learner. A negative pressure recess which is more profound than the front step bearing is made from the rail surface, and a side step bearing having a depth identical with the front step bearing is made from the rail surface.