A miniaturized piezoelectric Mössbauer spectrometer with feedback control.

A Mössbauer spectrometer was built and evaluated using an amplified piezoelectric actuator under feedback control for the Doppler velocity drive. The actuator was driven with a quadratic displacement waveform, giving a linear velocity profile. The optimization of the piezoelectric Doppler drive under feedback control was performed with measurements from a laser Doppler vibrometer.

Anharmonic Origin of the Giant Thermal Expansion of NaBr.

All phonons in a single crystal of NaBr are measured by inelastic neutron scattering at temperatures of 10, 300, and 700 K. Even at 300 K, the phonons, especially the longitudinal-optical phonons, show large shifts in frequencies and show large broadenings in energy owing to anharmonicity. Ab initio computations are first performed with the quasiharmonic approximation (QHA) in which the phonon frequencies depend only on V and on T only insofar as it alters V by thermal expansion.

Geriatric models of care for neurodegenerative disorders.

New models of care seek to reorganize healthcare to meet the challenges of a growing number of persons with chronic conditions, to optimize the use of the available workforce, and to improve the quality of care. Increasingly, these models also seek to organize care in a manner that addresses cost and efficiency in addition to quality of care. This chapter first revisits the history of chronic care models and then provides a description of successful and sustainable examples of integrated, multidisciplinary approaches for persons with dementia, persons with Parkinson's disease, and the frail elderly.

Entropic elasticity and negative thermal expansion in a simple cubic crystal.

While most solids expand when heated, some materials show the opposite behavior: negative thermal expansion (NTE). In polymers and biomolecules, NTE originates from the entropic elasticity of an ideal, freely jointed chain. The origin of NTE in solids has been widely believed to be different.