4,151 research outputs found
Race and “Hotspots” of Preventable Hospitalizations
Abstract
Preventable hospitalizations (PHs) are those for ambulatory care-sensitive conditions that indicate insufficiencies in local primary healthcare. PH rates tend to be higher among African Americans, in urban centers, rural areas and areas with more African American residents. The objective of this study is to determine geographic clusters of high PH rates (“spatial clusters”) by race. Data from Maryland hospitals were utilized to determine the rates of PHs in zip code tabulation areas (ZCTAs) by race in 2010. Geographic clusters of ZCTAs with higher than expected PH rates were identified using Scan Statistic and Anselin’s Local Moran’s I. 10 PH spatial clusters were observed among the total population with an average PH rate of 3,046.6 per 100,000 population. Among whites, the average PH rate was 3,339.9 per 100,000 in 11 PH spatial clusters. Only five PH spatial clusters were observed among African Americans with a higher average PH rate (3,710.8 per 100,000). The locations and other characteristics of PH spatial clusters differed by race. These results can be used to target resources to areas with high PH rates. Because PH spatial clusters are observed in differing locations for African Americans, approaches that include cultural tailoring may need to be specifically targeted
Notes on a new species of pedalion found in the Solomon Islands
The paper I have the honour to read before this Society
might be entitled, with some truth, " The History of a Lost
Opportunity." In a paper which I read before the Royal
Microscopical Society of London, in 1889, on a "New Species
of Megalotrocha," I spoke of Dunk Island, off the coast of
Queensland "I
found the water of such a solitary and lifeless pool literally
swarming with a wonderful pedalion." But at that time
(1888) I did not realise that this rotifer was a totally distinct
and new species. Last August (1893) whilst examining
some water collected in the artificially hollowed-out trunk
of a coconut tree, made by the natives of New Georgia for
drinking purposes, and growing on a small island in Eendoya
Harbour, Solomon Islands, I once again came across this
pedalion in considerable numbers. Then I recognised my
old friend of the Australian coast, and realised that it was
a new species, differing in essential details from the only
known species of Pedalion, P. mirum. Before I could,
however, complete mv examination of this rotifer, the news
arrived that this same species had been discovered by Dr.
Levander, of Helsingfors, in Finland, in October, 1892, and
had been named by him P. fennicum four years after I first
had seen it
Algorithms for 3D rigidity analysis and a first order percolation transition
A fast computer algorithm, the pebble game, has been used successfully to
study rigidity percolation on 2D elastic networks, as well as on a special
class of 3D networks, the bond-bending networks. Application of the pebble game
approach to general 3D networks has been hindered by the fact that the
underlying mathematical theory is, strictly speaking, invalid in this case. We
construct an approximate pebble game algorithm for general 3D networks, as well
as a slower but exact algorithm, the relaxation algorithm, that we use for
testing the new pebble game. Based on the results of these tests and additional
considerations, we argue that in the particular case of randomly diluted
central-force networks on BCC and FCC lattices, the pebble game is essentially
exact. Using the pebble game, we observe an extremely sharp jump in the largest
rigid cluster size in bond-diluted central-force networks in 3D, with the
percolating cluster appearing and taking up most of the network after a single
bond addition. This strongly suggests a first order rigidity percolation
transition, which is in contrast to the second order transitions found
previously for the 2D central-force and 3D bond-bending networks. While a first
order rigidity transition has been observed for Bethe lattices and networks
with ``chemical order'', this is the first time it has been seen for a regular
randomly diluted network. In the case of site dilution, the transition is also
first order for BCC, but results for FCC suggest a second order transition.
Even in bond-diluted lattices, while the transition appears massively first
order in the order parameter (the percolating cluster size), it is continuous
in the elastic moduli. This, and the apparent non-universality, make this phase
transition highly unusual.Comment: 28 pages, 19 figure
Self-organization with equilibration: a model for the intermediate phase in rigidity percolation
Recent experimental results for covalent glasses suggest the existence of an
intermediate phase attributed to the self-organization of the glass network
resulting from the tendency to minimize its internal stress. However, the exact
nature of this experimentally measured phase remains unclear. We modify a
previously proposed model of self-organization by generating a uniform sampling
of stress-free networks. In our model, studied on a diluted triangular lattice,
an unusual intermediate phase appears, in which both rigid and floppy networks
have a chance to occur, a result also observed in a related model on a Bethe
lattice by Barre et al. [Phys. Rev. Lett. 94, 208701 (2005)]. Our results for
the bond-configurational entropy of self-organized networks, which turns out to
be only about 2% lower than that of random networks, suggest that a
self-organized intermediate phase could be common in systems near the rigidity
percolation threshold.Comment: 9 pages, 6 figure
Self-organized criticality in the intermediate phase of rigidity percolation
Experimental results for covalent glasses have highlighted the existence of a
new self-organized phase due to the tendency of glass networks to minimize
internal stress. Recently, we have shown that an equilibrated self-organized
two-dimensional lattice-based model also possesses an intermediate phase in
which a percolating rigid cluster exists with a probability between zero and
one, depending on the average coordination of the network. In this paper, we
study the properties of this intermediate phase in more detail. We find that
microscopic perturbations, such as the addition or removal of a single bond,
can affect the rigidity of macroscopic regions of the network, in particular,
creating or destroying percolation. This, together with a power-law
distribution of rigid cluster sizes, suggests that the system is maintained in
a critical state on the rigid/floppy boundary throughout the intermediate
phase, a behavior similar to self-organized criticality, but, remarkably, in a
thermodynamically equilibrated state. The distinction between percolating and
non-percolating networks appears physically meaningless, even though the
percolating cluster, when it exists, takes up a finite fraction of the network.
We point out both similarities and differences between the intermediate phase
and the critical point of ordinary percolation models without
self-organization. Our results are consistent with an interpretation of recent
experiments on the pressure dependence of Raman frequencies in chalcogenide
glasses in terms of network homogeneity.Comment: 20 pages, 18 figure
Study of high resolution wind measuring systems. phase ii- analysis
Comparative analysis of high resolution wind measuring system
A New Methodology for Developing A Self-Report Psychodiversity Questionnaire: Update and Future Directions For A Work in Progress
A novel self-report methodology for the construction of a multidimensional questionnaire measure of psychodiversity is described and preliminary findings from three exploratory studies examining construct validity in relation to indices of well-being are discussed. Arising from these empirical endeavours, the notion of metamotivational state specific psychodiversity is proposed. The need for additional item generation for the combined alloic-autic and masterysympathy pairs is acknowledged. Suggestions are made for further research developing and using the resultant measure both within and beyond Reversal Theory
Clustering of matter in waves and currents
The growth rate of small-scale density inhomogeneities (the entropy
production rate) is given by the sum of the Lyapunov exponents in a random
flow. We derive an analytic formula for the rate in a flow of weakly
interacting waves and show that in most cases it is zero up to the fourth order
in the wave amplitude. We then derive an analytic formula for the rate in a
flow of potential waves and solenoidal currents. Estimates of the rate and the
fractal dimension of the density distribution show that the interplay between
waves and currents is a realistic mechanism for providing patchiness of
pollutant distribution on the ocean surface.Comment: 4 pages, 1 figur
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