A chair assembly including a toilet seat, a chair seat lid and a backrest. A coupler is attached to the panel and is removably coupled to the backrest. A magneto-rheological fluid is provided in the damping channel of the flow valve wherein the flow valve includes at least one magnetic device such that the damping channel of the flow valve can be exposed to a magnetic field of the magnetic device. The predetermined structure can include multiple context elements and directed relationships connecting the context elements, the directed relationships forming at least one cycle between the context elements.