Abstract: The present invention is an air purifier including an ionizing assembly that operates to charge particulate material in an air flow passing through the purifier. The charged particulate material is attracted to and retained by a filter element disposed downstream of the ionization assembly and having an electrical charge opposite to the charged particulate material. The purified air passing through the filter is directed out of the device, optionally in conjunction with a fragrance that is added to the purified air flow. The ionizing assembly is formed with a ground member disposed adjacent the ionizing member to keep the electrons generated by the ionizing assembly within the purifier, and thus prevent static discharges from occurring outside of the purifier. The air flow is directed by a fan through the purifier in an angular and substantially laminar manner, such that the efficiency of the purifier is increased.

Abstract: The present invention provides an assay device for detection of an analyte which is a member of a specific binding partner in a sample, the assay device comprising a sample application zone, a preabsorbing zone and a specific binding zone. The device can provide a HSV-2 specific assay by preabsorbing HSV-1 antibodies in the preabsorbing zone.

Abstract: Ventilation ducting having a substantially oval and/or elliptical cross-section includes an intermediate section, and an end section at opposite ends of the intermediate section. Both the intermediate and the end sections include a pair of adjacent ducts. The ducts in the intermediate section are separated along their length by a common wall. The common wall may be perforated sheet, mesh or net material. The ducts at each end section are separate tubular members. An engaging device is provided at the intermediate section for suspending the ducting above the ground. A coupling device is provided at each end of the intermediate section for joining together adjacent lengths of the ventilation ducting.