Abstract: In a total hip replacement, a stem of a femoral component is disposed in a patient's thigh bone with a ball extending in such femoral component above the stem. The ball is disposed in a hemispherical cup positioned in the patient's pelvis and enveloping the ball for frontal movement of the ball relative to the cup. A low-friction liner (e.g., plastic or ceramic) is disposed at the bottom of the cup. To determine whether the ball is properly positioned in the cup, a first member (e.g., a coil) is disposed on the bottom of the liner. A second member (e.g., a patch defining a loop) is disposed on the patient's thigh in operatively coupled (e.g. magnetic) relationship to the first member. The operative coupling between the members is variable in accordance with variations in the disposition of the ball in the cup. When the first and second members are respectively a coil and a patch, the coil and a capacitance may be fixed in the patient's body in a circuit resonant at a particular frequency.

Abstract: An apparatus illustrated in two embodiments assists a sole worker in the positioning and installing of ceiling panels, such as sheetrock, to ceiling joists. In the first embodiment, a panel is placed on an arm pivotably connected to a post firmly positioned between a floor and a ceiling. Upon the release of a lever, a pressurized gas cylinder causes the arm to lift the panel angularly into substantially horizontal orientation adjacent the ceiling joists. In the second embodiment a plate formed with a ramp portion extends at an angle to a bearing plate portion. The bearing plate portion is fastened to a ceiling joist with the ramp portion angled downward. A first edge of a ceiling panel is placed on the ramp and the opposite edge of the ceiling panel is lifted by a worker so that the first edge is forced upward on the ramp to rest on the bearing portion as the second edge is brought into a substantially horizontal position.