A microscope has an oil immersion system objective and an imaging lens to make observations by charging oil between a cover glass protecting a sample and the most sample-side lens surface. The bone anchor of the invention incorporates a deformable body that creates an increased anchor body diameter after it is inserted into the cancellous bone and deployed beneath the cortical surface of the bone. In certain embodiments, the power conversion unit may be a stand-alone system or may be incorporated into a device, such as a wire feeder, which is configured to derive power from the arc potential. If a broadcast program is newly selected under a condition where the recording of the currently received broadcast program is prohibited, the recording flag is reset to 0 and the first received video section of the newly selected broadcast program is recorded onto the rewritable optical disc.