A computer-implemented method for detecting fraudulent payment transactions performed over a payment network is provided. The page buffer comprises a first latch configured to store first even page data of the even page cell group when a first read operation is performed, a second latch configured to store odd page data of the odd page cell group when a second read operation is performed, and a third latch configured to store second even page data of the even page cell group when a third read operation is performed. Clarified wax is removed at the top of the settler. Additionally, an automatic stop feature prevents a sensor cable from retracting without depression of the lever, thus maintaining the exact length of cable required to connect a monitor to the monitoring site on a patient.