A magnetic sensor for reproducing information recorded on a magnetic recording medium senses an external magnetic field using a spin-filtered sensor current flowing through a non-magnetic layer. The compounds are generally aryl piperazine derivatives and are useful in pharmaceutical compositions, methods for the treatment of CCR1-mediated diseases, and as controls in assays for the identification of competitive CCR1 antagonists. The processing performed by the computer includes a fine-tuning capability for positioning the cursor at point on the video screen substantially overlapping the point of regard, and a gaze activated method for selecting computer actions. Specifically, crosstalk and more particularly upstream near end crosstalk in the presence of narrowband interference can be classified to isolate the particular service type causing the upstream NEXT. Preferably, the gate itself is heavily doped so that one half of the gate on the side adjacent the heavily doped P region is also heavily doped with dopants of P-type conductivity and the other half of the gate on the side adjacent the heavily doped N region is also heavily doped with dopants of N-type conductivity.