Athenian cultural dominance continued throughout the Roman period, and the buildings added to the Agora reflect the educational role of the city, a role that ended only with the closing of the pagan philosophical schools by the Christian emperor Justinian in A.D. 529.
Bearing, in machine construction, a connector (usually a support) that permits the connected members to rotate or to move in a straight line relative to one another. Often one of the members is fixed, and the bearing acts as a support for the moving member. Most bearings support rotating shafts against either transverse (radial) or thrust (axial) loads.
The hub bearing assembly is part of the mechanism of a car wheel. It is the assembly of hubs and bearings that facilitate the rotation of the wheel on the road surface. The hub bearing assembly consists of a wheel hub on which the bearings are mounted. The hub is attached to the axle and the bearings keep the wheel spinning smoothly. Hub bearing assemblies differ between front and back wheel sets.