A clock with a twenty four hour display includes a minute hand, a second hand, a minute scale, a date display, and an hour scale on a first conchoid. The facility receives an indication that a user has captured a machine-readable symbol encoding an identifier that identifies a particular online discussion. The power level detection circuit also has a control circuit coupled to the first, second and third signals for outputting a power level detection signal if there is a change in the second signal, and when the power level is greater than the level of the third signal and less than the level of the first signal. With respect to the culturing of malignant cells, for example, it is believed that by maintaining the malignant cells within a multicellular particulate of the originating tissue, growth of the malignant cells themselves is facilitated versus the overgrowth of fibroblasts or other cells which tends to occur when suspended tumor cells are grown in culture. The controller uses a comparison algorithm to determine what fluid settings in the valve are necessary to effect a desired fluid flow through the valve, and prepares an input signal to be sent to one or more motors controlling the translational and rotational motion of the cam.