Although Americans embrace cutting-edge technology, the negative impacts of a lifestyle dependent upon such progress prompt many to feel "environmental guilt," says a UC Davis environmental design professor. "Americans, in increasing numbers and intensities, feel guilty about what technological development has done to the landscape," says Robert Thayer Jr., whose book "Gray World, Green Heart" will be published in December by John Wiley and Sons. Such guilt, Thayer says, is most acute in North America, though ecological degradation is found around the world. An example of environmental guilt expressed in the landscape is "NIMBY" (Not In My Back Yard) attitudes toward development and siting of facilities such as power plants, airports and waste repositories. Thayer also cites other examples such as zoning that keeps technology at a distance from homes and recreational areas and the concealment of air conditioners or electric substations behind architectural facades. As for the root cause of such guilt, Thayer says Americans may feel some remorse that science and technology have so thoroughly replaced religion as the primary force guiding lifestyle and behavior.