You may use air admittance valves to vent individual vents, branch vents, circuit vents, and stack vents. Use individual and branch type air admittance valves to vent fixtures that are on the same floor level and that are connected to a horizontal branch drain.
Overview. The ventricles of the brain are a communicating network of cavities filled with cerebrospinal fluid (CSF) and located within the brain parenchyma. The ventricular system is composed of 2 lateral ventricles, the third ventricle, the cerebral aqueduct, and the fourth ventricle (see the following images).he rest of the CSF production is the result of transependymal flow from the brain to the ventricles. CSF flows from the lateral ventricles, through the interventricular foramens, and into the third ventricle, cerebral aqueduct, and the fourth ventricle.
The Ventricular System. Within the brain there are four ventricles: two lateral (meaning away from the midline of the body), a third ventricle near the center of the brain and the fourth ventricle under the cerebellum. They are all connected by smaller passageways that allow the CSF to circulate slowly among them.