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Concerns about air pollution, climate change, and oil supply insecurity, requires changes in automotive engine/fuel technologies in directions, that offer both the potential for achieving near-zero emission of air pollutants, and a substitute of petroleum. Alternative automotive engine/fuel options, which are evolving towards these goals, are compared and discussed.

As the number of cars and the amount of driving increase, it becomes necessary to reduce air pollutant emissions per car in order to meet air quality goals. Yet it [...]

Several factors must first be considered before purchasing a charge-coupled device (CCD) camera. Buyers must first examine the camera's quantum efficiency (QE) versus wavelength plot. QE measurements are often made by the CCD manufacturer and simply passed along to the camera maker. In choosing the right camera, the performance of the CCD must first be assessed against the user's requirements. Deciding how much read and dark noise can be tolerated for a specific use can pose a lot of problems. Low-read noise MPP cameras are used for low light level spectroscopy while TE-cooled cameras are used for high light level spectroscopy.

Severe local air pollution, aggravation of the global warming condition and the inaccessibility of coal reserves in China have fueled interest into alternative sources of electricity, such as wind power. Wind power has been in use in China for over 3,000 years. Studies showed that it can provide the same amount of electricity in distant electricity demand centers by combining oversized wind farms, utilizing long-distance transmission lines and large-scale electrical storage. However, problems in funding and the legal structure of the scheme must be addressed.

Alternative sources of energy that are environment friendly are needed to maintain sustainable progress well into the future. Despite current environmental problems caused by fossil fuels, prospects are high for technologies providing new sources of energy. Sustainable development requires efficiency in energy use as well as sources that are beneficial to theenvironment. In this respect, the US needs to implement a new energy policy that would encourage increased energy output and the creation and marketing of new energy sources friendly to the environment.

Abstract Nitric oxide (NO) is a free radical that plays an important role in modulating platelet adhesion and aggregation. Platelets are a source of vascular NO, but since erythrocytes avidly scavenge NO, the functional significance of platelet-derived NO is not clear. Our purpose was to determine if NO from platelets affects platelet thrombus formation in the presence of anticoagulated whole blood in an in vitro parallel plate flow system. We studied platelet adhesion and aggregation on a collagen type III surface in the presence of physiologically relevant fluid mechanical shear stress. We found that certain receptor mediated agonists (insulin and isoproterenol) caused a concentration dependent reduction in thrombus formation at a shear rate of 1000 s-1. This effect was mediated by NO since it was abolished in the presence of the NO inhibitor L-nitro-arginine-methyl-ester (L-NAME). As expected, at venous levels of shear rate (100 s-1) neither of the agonists had any effect on thrombus formation since platelet adhesion does not depend on activation at these low levels of shear. Interestingly, at a shear rate of 2000 s-1 the addition of L-NAME caused an increase in platelet coverage suggesting that shear, by itself, induces NO production by platelets. This is the first demonstration of shear stress causing platelets to produce an inhibitor of platelet activation. These results demonstrate that the development of a platelet thrombus is regulated in a complex way and that platelets produce functionally significant amounts of NO even in the presence of whole blood.

Study designed to determine which version of a game developed in strict compliance with competing models of incentive and dissonance would be more effective in producing attitude change found that results were similar in the experimental groups. Similarity is attributed to sense of identification with simulation characters reported by subjects. (MBR)

Discussion of conditions under which simulation games promote changes in attitudes focuses on identification theory as a predictor of attitude change. Incentive theory and cognitive dissonance theory are discussed, and a study of community college students is described that tested the role of identification in changing attitudes. (LRW)

Three groups of 109 undergraduates evidenced attitude shifts from participation to simulation games which were structured in accordance with either the cognitive dissonance or incentive models of attitude change. Identification was suggested as an extra factor influencing attitude change. (CMV)

An educational model to realize the goal of dynamic intellectualism is presented. The model consists of a framework of integrative and subject-specific objectives, and a series of learning activities in the twin domains of theory and practice with which to meet the objectives. (SK)