"Managed Care, Physician Incentives, and Norms of Medical Practice: Racing to the Bottom or Pulling to the Top?"

The incentive contracts that managed care organizations write with physicians have generated considerable controversy. Critics fear that if informational asymmetries inhibit patients from directly assessing the quality of care provided by their physician, competition will lead to a "race to the bottom" in which managed care plans induce physicians to offer only minimal levels of care. To analyze this issue we propose a model of competition between managed care organizations. The model serves for both physician incentive contracts and HMO product market strategies in an environment of extreme information asymmetry--physicians perceive quality of care perfectly, and patients don't perceive it at all. We find that even in this stark setting, managed care organizations need not race to the bottom. Rather, the combination of product differentiation and physician practice norms causes managed care organizations to race to differing market niches, with some providing high levels of care as a means of assembling large physician networks. We also find that relative physician practice norms, defined endogenously by the standards of medical care prevailing in a market, exert a "pull to the top" that raises the quality of care provided by all managed care organizations in the market. We conclude by considering the implications of our model for public policies designed to limit the influence of HMO incentive systems.

"Physician Incentives In Managed Care Organizations: Medical Practice Norms and the Quality of Care"

This brief considers the interaction between physician incentive systems and product market competition in the delivery of medical services via managed care organizations. At the center of the analysis is the process by which health maintenance organizations (HMOs) assemble physician networks and the role these networks play in the competition for customers. The authors find that although physician practice styles respond to financial incentives, there is little evidence that HMO cost-containment incentives cause a discernable reduction in care quality. They propose a model of the managed care marketplace that solves for both physician incentive contracts and HMO product market strategies in an environment of extreme information asymmetry: physicians perceive the quality of care they offer perfectly and their patients do not perceive it at all.

AutoSOME: a clustering method for identifying gene expression modules without prior knowledge of cluster number

<p>Abstract</p> <p>Background</p> <p>Clustering the information content of large high-dimensional gene expression datasets has widespread application in "omics" biology. Unfortunately, the underlying structure of these natural datasets is often fuzzy, and the computational identification of data clusters generally requires knowledge about cluster number and geometry.</p> <p>Results</p> <p>We integrated strategies from machine learning, cartography, and graph theory into a new informatics method for automatically clustering self-organizing map ensembles of high-dimensional data. Our new method, called AutoSOME, readily identifies discrete and fuzzy data clusters without prior knowledge of cluster number or structure in diverse datasets including whole genome microarray data. Visualization of AutoSOME output using network diagrams and differential heat maps reveals unexpected variation among well-characterized cancer cell lines. Co-expression analysis of data from human embryonic and induced pluripotent stem cells using AutoSOME identifies >3400 up-regulated genes associated with pluripotency, and indicates that a recently identified protein-protein interaction network characterizing pluripotency was underestimated by a factor of four.</p> <p>Conclusions</p> <p>By effectively extracting important information from high-dimensional microarray data without prior knowledge or the need for data filtration, AutoSOME can yield systems-level insights from whole genome microarray expression studies. Due to its generality, this new method should also have practical utility for a variety of data-intensive applications, including the results of deep sequencing experiments. AutoSOME is available for download at <url>http://jimcooperlab.mcdb.ucsb.edu/autosome</url>.</p

Managing Wild Pigs: A Technical Guide

Wild pigs are and will continue to be a challenging problem for wildlife managers, landowners, farmers, conservationists, and others. Despite ongoing control programs, wild pigs have increased both their range and population size. Because of this growth, wildlife managers will increasingly be involved in dealing with problems caused by wild pigs traditionally, as well as emerging problems such as landscaping damage in suburban areas. Successful management strategies will depend upon persistent, adaptive, and integrated management programs that incorporate sound biological and ecological information. An integrated management approach, in addition to addressing the biological and ecological aspects of wild pigs, will seek to engage stakeholders via comprehensive education and communication programs. We hope this guide can be a valuable tool in that crucial task.https://digitalcommons.usu.edu/hwi_monographs/1000/thumbnail.jp

Under Pressure: Quenching Star Formation in Low-Mass Satellite Galaxies via Stripping

Recent studies of galaxies in the local Universe, including those in the Local Group, find that the efficiency of environmental (or satellite) quenching increases dramatically at satellite stellar masses below ~ $10^8\ {\rm M}_{\odot}$. This suggests a physical scale where quenching transitions from a slow "starvation" mode to a rapid "stripping" mode at low masses. We investigate the plausibility of this scenario using observed HI surface density profiles for a sample of 66 nearby galaxies as inputs to analytic calculations of ram-pressure and viscous stripping. Across a broad range of host properties, we find that stripping becomes increasingly effective at $M_{*} < 10^{8-9}\ {\rm M}_{\odot}$, reproducing the critical mass scale observed. However, for canonical values of the circumgalactic medium density ($n_{\rm halo} < 10^{-3.5}$${\rm cm}^{-3}$), we find that stripping is not fully effective; infalling satellites are, on average, stripped of < 40 - 70% of their cold gas reservoir, which is insufficient to match observations. By including a host halo gas distribution that is clumpy and therefore contains regions of higher density, we are able to reproduce the observed HI gas fractions (and thus the high quenched fraction and short quenching timescale) of Local Group satellites, suggesting that a host halo with clumpy gas may be crucial for quenching low-mass systems in Local Group-like (and more massive) host halos.Comment: updated version after review, now accepted to MNRAS; Accepted 2016 August 22. Received 2016 August 18; in original form 2016 June 2

A study of vision screening for kindergarteners

A study of vision screening for kindergartener

The Gibbs-Thomson formula at small island sizes - corrections for high vapour densities

In this paper we report simulation studies of equilibrium features, namely circular islands on model surfaces, using Monte-Carlo methods. In particular, we are interested in studying the relationship between the density of vapour around a curved island and its curvature-the Gibbs-Thomson formula. Numerical simulations of a lattice gas model, performed for various sizes of islands, don't fit very well to the Gibbs-Thomson formula. We show how corrections to this form arise at high vapour densities, wherein a knowledge of the exact equation of state (as opposed to the ideal gas approximation) is necessary to predict this relationship. Exploiting a mapping of the lattice gas to the Ising model one can compute the corrections to the Gibbs-Thomson formula using high field series expansions. We also investigate finite size effects on the stability of the islands both theoretically and through simulations. Finally the simulations are used to study the microscopic origins of the Gibbs-Thomson formula. A heuristic argument is suggested in which it is partially attributed to geometric constraints on the island edge.Comment: 27 pages including 7 figures, tarred, gzipped and uuencoded. Prepared using revtex and espf.sty. To appear in Phys. Rev.

The Metal-Poor Halo of the Andromeda Spiral Galaxy (M31)

We present spectroscopic observations of red giant branch (RGB) stars over a large expanse in the halo of the Andromeda spiral galaxy (M31), acquired with the DEIMOS instrument on the Keck II 10-m telescope. Using a combination of five photometric/spectroscopic diagnostics -- (1) radial velocity, (2) intermediate-width DDO51 photometry, (3) Na I equivalent width (surface gravity sensitive), (4) position in the color-magnitude diagram, and (5) comparison between photometric and spectroscopic [Fe/H] estimates -- we isolate over 250 bona fide M31 bulge and halo RGB stars located in twelve fields ranging from R = 12-165kpc from the center of M31 (47 of these stars are halo members with R > 60 kpc). We derive the photometric and spectroscopic metallicity distribution function of M31 RGB stars in each of these fields. The mean of the resulting M31 spheroid (bulge and halo) metallicity distribution is found to be systematically more metal-poor with increasing radius, shifting from = -0.47+/-0.03 (sigma = 0.39) at R = -0.94+/-0.06 (sigma = 0.60) at R ~ 30 kpc to = -1.26+/-0.10 (sigma = 0.72) at R > 60 kpc, assuming [alpha/Fe] = 0.0. These results indicate the presence of a metal-poor RGB population at large radial distances out to at least R = 160 kpc, thereby supporting our recent discovery of a stellar halo in M31: its halo and bulge (defined as the structural components with R^{-2} power law and de Vaucouleurs R^{1/4} law surface brightness profiles, respectively) are shown to have distinct metallicity distributions. If we assume an alpha-enhancement of [alpha/Fe] = +0.3 for M31's halo, we derive = -1.5+/-0.1 (sigma = 0.7). Therefore, the mean metallicity and metallicity spread of this newly found remote M31 RGB population are similar to those of the Milky Way halo.Comment: Accepted for publication in ApJ on May 4th, 2006 (submitted on Jan 30, 2006). 16 pages, 13 figures, 3 table

Mini-mast CSI testbed user's guide

The Mini-Mast testbed is a 20 m generic truss highly representative of future deployable trusses for space applications. It is fully instrumented for system identification and active vibrations control experiments and is used as a ground testbed at NASA-Langley. The facility has actuators and feedback sensors linked via fiber optic cables to the Advanced Real Time Simulation (ARTS) system, where user defined control laws are incorporated into generic controls software. The object of the facility is to conduct comprehensive active vibration control experiments on a dynamically realistic large space structure. A primary goal is to understand the practical effects of simplifying theoretical assumptions. This User's Guide describes the hardware and its primary components, the dynamic characteristics of the test article, the control law implementation process, and the necessary safeguards employed to protect the test article. Suggestions for a strawman controls experiment are also included

Large-scale implementation of adaptation and mitigation actions in agriculture

This paper identifies sixteen cases of large-scale actions in the agriculture and forestry sectors that have adaptation and/or mitigation outcomes, and distils lessons from the cases. The cases cover policy and strategy development (including where climate-smart objectives were not the initial aim), climate risk management through insurance, weather information services and social protection, and agricultural initiatives that have a strong link to climate change adaptation and mitigation. Key lessons learned include: - Trade-offs can be avoided, at least in the near-term and over limited spatial scale - We need cost-effective and comparable indices for measuring GHG fluxes and for monitoring adaptive capacity - Strong government support is crucial to enable large-scale successes - Upfront costs may be substantial and can be met from multiple sources - An iterative and participatory learning approach with investment in capacity strengthening is critical