Implementation of the 2002 Ohio nursing home family satisfaction survey : final report

In 2002, the Scripps Gerontology Center conducted the second annual nursing home family satisfaction survey under a contract to the Ohio Dept. of Aging. Seven hundred thirty-six of the 902 nursing homes on the mailing list had at least one survey returned by a family member. Nearly half (48%) of nursing home resident families responded, for a total return of 16,955 family responses. Refinements to the survey instrument showed continued high reliability of domain areas and the instrument as a whole. Changes in instructions to families, and a number of processes were changed this year that resulted in fewer family and facility calls requesting assistance from the toll-free hotline operated by the Margaret Blenkner Research Institute at Benjamin Rose. Comparisons of 2001 and 2002 responses show some significant improvements statewide, with more items showing statewide averages of 90 and above. Among facilities that participated both years, a number of areas also showed statistically significant improvements. The family satisfaction survey is one important component of the comprehensive nursing home information shown on the Ohio Long-Term Care Consumer Guide (www.ltcohio.org)

STM-induced surface aggregates on metals and oxidized silicon

We have observed an aggregation of carbon or carbon derivatives on platinum and natively oxidized silicon surfaces during STM measurements in ultra-high vacuum on solvent-cleaned samples previously structured by e-beam lithography. We have imaged the aggregated layer with scanning tunneling microscopy (STM) as well as scanning electron microscopy (SEM). The amount of the aggregated material increases with the number of STM scans and with the tunneling voltage. Film thicknesses of up to 10 nm with five successive STM measurements have been obtained

Speckle visibility spectroscopy and variable granular fluidization

We introduce a dynamic light scattering technique capable of resolving motion that changes systematically, and rapidly, with time. It is based on the visibility of a speckle pattern for a given exposure duration. Applying this to a vibrated layer of glass beads, we measure the granular temperature and its variation with phase in the oscillation cycle. We observe several transitions involving jammed states, where the grains are at rest during some portion of the cycle. We also observe a two-step decay of the temperature on approach to jamming.Comment: 4 pages, 4 figures, experimen

Kink-induced transport and segregation in oscillated granular layers

We use experiments and molecular dynamics simulations of vertically oscillated granular layers to study horizontal particle segregation induced by a kink (a boundary between domains oscillating out of phase). Counter-rotating convection rolls carry the larger particles in a bidisperse layer along the granular surface to a kink, where they become trapped. The convection originates from avalanches that occur inside the layer, along the interface between solidified and fluidized grains. The position of a kink can be controlled by modulation of the container frequency, making possible systematic harvesting of the larger particles.Comment: 4 pages, 5 figures. to appear in Phys. Rev. Let

Slow relaxation in granular compaction

Experimental studies show that the density of a vibrated granular material evolves from a low density initial state into a higher density final steady state. The relaxation towards the final density value follows an inverse logarithmic law. We propose a simple stochastic adsorption-desorption process which captures the essential mechanism underlying this remarkably slow relaxation. As the system approaches its final state, a growing number of beads have to be rearranged to enable a local density increase. In one dimension, this number grows as $N=\rho/(1-\rho)$, and the density increase rate is drastically reduced by a factor $e^{-N}$. Consequently, a logarithmically slow approach to the final state is found $\rho_{\infty}-\rho(t)\cong 1/\ln t$.Comment: revtex, 4 pages, 3 figures, also available from http://arnold.uchicago.edu/~ebn

Size segregation and convection

The size segregation of granular materials in a vibrating container is investigated using Molecular Dynamics. We find that the rising of larger particles is accompanied by the existence of convection cells even in the case of the lowest possible frequencies. The convection can, however, also be triggered by the larger particle itself. The possibility of rising through this mechanism strongly depends on the depth of the larger particle.Comment: 7 pages, 4 figure