Your CD4 count. These cells are a type of white blood cell that is destroyed by HIV. A healthy person's count varies from 500 - over 1,000. If you have fewer than 200 CD4 cells, then your HIV has progressed to AIDS.
Aircraft fluid lines are usually made of metal tubing. or flexible hose. Metal tubing (also called rigid fluid. lines) is used in stationary applications and where long, relatively straight runs are possible. They are widely. used in aircraft for fuel, oil, coolant, oxygen, instru-. ment, and hydraulic lines. Flexible hose is generally. used with moving parts or where the hose is subject. to considerable vibration. Occasionally, it may be necessary to repair or replace. damaged aircraft fluid lines.
Control line. Control line (also called U-Control) is a simple and light way of controlling a flying model aircraft. The aircraft is connected to the operator by a pair of lines, attached to a handle, that work the elevator of the model. This allows the model to be controlled in the pitch axis.