Abstract: A cytometer includes an avalanche photodiode, a switching power supply, a filter, and voltage adjustment circuitry. The switching power supply includes a feedback loop. The filter is electrically connected between the switching power supply and the avalanche photodiode. The voltage adjustment circuitry adjusts a voltage on the feedback loop based at least in part on a voltage measured between the filter and the avalanche photodiode.

Abstract: A display and a method of displaying articles for sale in a mass retail environment. The method comprises displaying multiple product containers in an adjacent fashion, in a row, on a shelf, where each container includes the same brand display. The method further comprises including product containers having a common characteristic selected from the group consisting of fragrance, product color, container shape, container color and combinations thereof. The products include at least two product types selected from the group consisting of personal care products, home care products, and laundry care products.