A complimentary single-ended-input OTA-C universal filter structures in terms of integrated circuits is provided. The sheet has a central nose engaging area, a pair of viewing areas on opposite sides of the nose engaging area and a pair of temple engaging areas each extending from one of the viewing areas. Combustion air passages correspond to, and align with the air passages in the nozzle. An irradiation assembly and a method for test printing are also described. Advantageously, in the biochip reader, a lower SN ration is obtained together with lower cost; and in the electrophoresis system, concurrent detection of multiple polychromatic fluorescence patters is attained. The lead testing assembly may be freestanding or may be incorporated into an existing testing instrument.