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We have observed the propagation of sound in liquid He 3 at 0.32 atm and at frequencies of 15.4 and 45.5 MHz down to a temperature T* of 2 mdeg on the magnetic temperature scale valid for powdered cerium magnesium nitrate (CMN) in the form of a right circular cylinder with diameter equal to height. As the temperature rises the sound attenuation increases, reaches a maximum, and then decreases. At low temperatures the attenuation is proportional to T* 2 and is independent of frequency. At high temperatures the attenuation is proportional to co 2 /T* 2 , where co is the angular frequency. The sound propagation velocity is relatively temperature independent at both high and low temperatures but near the attenuation maximum the velocity changes.In 1957 Landau 1 predicted that at sufficiently low temperatures a new type of sound, which he called zero sound, could be propagated in liquid He 3 . Based on Landau's idea, a more detailed theory of the velocity and attenuation of sound in both the hydrodynamic (first sound) and zero-sound regions was worked out by Khalatnikov and Abrikosov. 2 At temperatures sufficiently high that quantum effects are unimportant, it is predicted that the attenuation of zero sound be proportional to T 2 and independent of frequency. In the first-sound region it is predicted that the attenuation is proportional to OJ 2 /T 2 , corresponding to classical viscous attenuation with viscosity proportional to T~2. Both of these temperature and frequency dependences are observed in the present experiments. In what follows we shall show that there is quantitative agreement with theory on veloc-

In a study of the low-temperature anomalies which appear in disordered solids we have measured the specific heat, thermal conductivity, thermal expansion, and dielectric dispersion for a carefully prepared series of (Si02)~"(K20)"and (Si02)~"(Na20)"glasses. Each sample had a known glass transition temperature Tg, mass density, phonon velocities, covalency, and density and concentration fluctuations. The only significant correlation occurred between the phonon mean free path and the glass-transition temperature. No explicit support was found for any model developed to explain the specific heat and/or thermal conductivity of glasses.

Current approaches to health care quality have failed to reduce health care disparities. Despite dramatic increases in the use of quality measurement and associated payment policies, there has been no notable implementation of measurement strategies to reduce health disparities. The National Quality Forum developed a road map to demonstrate how measurement and associated policies can contribute to eliminating disparities and promote health equity. Specifically, the road map presents a four-part strategy whose components are identifying and prioritizing areas to reduce health disparities, implementing evidence-based interventions to reduce disparities, investing in the development and use of health equity performance measures, and incentivizing the reduction of health disparities and achievement of health equity. To demonstrate how the road map can be applied, we present an example of how measurement and value-based payment can be used to reduce racial disparities in hypertension among African Americans.

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