An acetabular reamer for cutting a required cut shape. The apparatus comprises a cutting mechanism and a holding mechanism. Methods of detecting individual cells, particularly rare cells from large heterogeneous cell populations, through detection of nucleic acids are described. For at least one zone, a projected time at which the zone will reach a target index value is determined based on the linear function, and the polishing parameter for at least one zone on at least one substrate is adjusted such that the at least one zone of the at least one substrate has closer to the target index at the projected time than without such adjustment. Accordingly, the object is placed at a desirable position in the scene. As a result, the records of the apartment data can be compared to the records of the home data on an equivalent basis.