A directory event system for providing timely event notifications of each data manipulation of a master directory database and for providing timely event notifications of each corresponding data replication to a replicate directory database is disclosed. A plurality of electrodes may be disposed about an elongate shaft. The present invention may be adapted for use with cyclonic separation devices of all types, including single- and multi-stage cyclonic separators. The position of the tool tip can be digitized relative to fiducial markers visible in an MRI experiment. The light diffuser may reduce directionality in the ambient light sensor. The operating voltages are based on the selected load resistor and the current-voltage characteristics for the diode of the rectifying circuit at the associated spectrum portion.