Troxel utilized sleep monitoring equipment to measure the patients’ length of continuous sleep, interrupted sleep, length of different stages of sleep, and body movements.

Troxel utilized sleep monitoring equipment to measure the patients' length of continuous sleep, interrupted sleep, length of different stages of sleep, and body movements.

Synchronized movements of the six-way valve and DIV made it possible to establish a simple flow path of the sample and a continuous liquid flow through the column.