Abstract: Sulphated vinyl polymers such as sulphated polyvinylalcohol, sulphated copolymers of (meth)acrylic acid and vinylalcohol, and pharmaceutically acceptable salts thereof, have an antiviral effect against human immunodeficiency virus and may therefore be used as a therapeutic agent for treating retrovirus infections like AIDS and AIDS-related diseases. Their antiviral activity is apparently based on inhibition of virus adsorption; their inhibitory effect on giant cell formation is stronger than that of dextran sulphate.

Abstract: A flume distribution system includes a distributor having a stationary lower portion and a removable upper portion. The lower portion defines a duct which is in fluid communication with a flume and at least one underdrain lateral. The lower portion also includes an apertured end wall which abuts one of the underdrain laterals at a lateral inlet, and a stop is disposed within the duct and spaced from the end wall. The duct receives a removable orifice plate which is adapted to pivot between a slant inactive position abutting the stop and an upright active position restricting the aperture in the end wall. During backwash operations, water is introduced to the flume and enters each duct in the lower portion of the distributor, and the pressure of the incoming water causes the orifice plate to pivot from the slant position to the upright position, reducing the cross-sectional area of the aperture in the end wall and thereby regulating the velocity of backwash flow from the flume into the lateral inlet.