A temperature independent reference circuit includes first and second bipolar transistors with commonly coupled bases. The systems may further comprise a bioactive agent. This combination inhibits abrasion of the tie for the life of the tie. Each of a plurality of trenches extending into the drift region perpendicular to the current flow includes a dielectric layer lining at least a portion of the trench sidewalls and at least one conductive electrode. In addition, a caller may redeem advancement tokens earned in a previous hold queue while waiting in current hold queue, where the redeemable advancement tokens are accessible across multiple call centers according to the caller identification. The method includes the steps of: capturing an image of a portion of the coding pattern; and low-pass filtering the captured image so as to obscure data elements in the image and preserve target elements in the image.