When you get up in the morning and just before sleep, you are naturally in this state. When you close your eyes your brain automatically starts producing more alpha waves. Many studies monitoring the EEG activity of experienced meditators have revealed strong increases in alpha activity.
Bottom-up processing happens when someone tries to understand language by looking at individual meanings or grammatical characteristics of the most basic units of the text, (e.g. sounds for a listening or words for a reading), and moves from these to trying to understand the whole text.
Flushing is a process by which water is moved through a water pipe at a high velocity so that a scouring action is created. Water is then discharged through a hydrant which in turn removes any material build-up from the pipe. The material removed from this process is harmless and requires no special treatment.