Abstract: An optical stack for sensing a presence of an analyte is provided. The optical stack includes a sensor material. The sensor material includes a first optical response including a first optical property having a second value in response to an excitation signal including the first optical property having a first value different from the second value. The first optical response includes a second optical property sensitive to the presence of the analyte. The optical stack includes a first optical film disposed proximate the sensor material and includes a third optical property having respective third and fourth values in response to the respective first and second values of the first optical property. The third value is different from the fourth value by at least a factor of 2.

Abstract: A disk drive selects seek speed and seek acoustics based on a history of seek requests from a host computer. The history of seek requests can include time intervals between seek requests, seek lengths of seek requests, locations of seek requests, a backlog of seek requests, whether seek requests are read requests or write requests, and whether seek requests are sequential or random.