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.
CSF flows out of the ventricles of the brain where it is produced and into the subarachnoid space of the brain and cord. Some CSF also flows down through a channel in the center of the cord called the central canal. The central canal, however, appears to close with age.SF is produced in the chambers of the brain called ventricles. The two highest ventricles in the brain are the lateral ventricles. The third ventricle lies below them and the fourth ventricle lies below the third. A dense plexus of blood vessels, called the telea choroidea, lies close to the ventricles.