Abstract: This invention relates to procedures for the calibration of systems for continuously measuring the concentration of substances in a body fluid. The system comprises first and second sensors adapted for subcutaneous insertion and an electronic calculator unit adapted for measuring signals from the two sensors. The system is calibrated following the steps of: a) introducing the first sensor subcutaneously, b) calibrating the first sensor, c) obtaining sensor data S1(t) provided by the first sensor, d) introducing the second sensor subcutaneously, e) obtaining sensor data S2(t) provided by the second sensor, f) determining the rate of change over time ?R(t)/?t, R(t) being a signal which correlates to sensor data S2(t) over time, and g) performing a calibration of the second sensor when ?R(t)/?t is less than a predetermined value, said calibration of the second sensor being performed using sensor data S1(t) obtained by the first sensor.

Abstract: A graphical user interface provides access to communications and other applications in a home environment by utilizing icons that are consistent with a refrigerator/magnet metaphor. A background is displayed on a touch screen, and one or more virtual magnets are displayed on the background. The virtual magnets may be dragged to new locations by a user. Tapping on a virtual magnet activates a corresponding application. The virtual magnets can further exhibit magnetic properties, such as alternatively repelling or attracting one another. When an application is activated, an application window is made to appear on the background, preferably in the form of a sheet of paper. The corresponding virtual magnet can be made to appear to be affixing the sheet of paper to the background, thereby reinforcing the refrigerator/magnet metaphor.