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    Implementing Health Reform at the State Level: Access and Care for Vulnerable Populations

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    The Affordable Care Act1 (ACA) promises to improve access to coverage and care for two vulnerable groups: low-income persons who are excluded by a lack of resources and chronically ill and disabled people who are excluded by the dysfunction of our existing insurance and care delivery systems. ACA’s sprawling provisions raise a wealth of implementation challenges that are exacerbated by the compromises required to move reform through Congress. In particular, the compromise between regulatory/public program advocates and advocates for private, market-driven programs requires thoughtful regulatory coordination between public and private health systems. The anticipated increase in coverage is roughly split between expansions in Medicaid and private enrollment, each of which is projected to cover approximately 16 million Americans.2 How ACA will be implemented has been the subject of constant attention since its enactment, and federal regulators have been generating program and regulatory information with commendable assiduity. However, state-level reform will be crucial to the effectiveness of the ACA implementation for low-income and chronically ill people. Federal structural regulations will be implemented and interpreted at the state level. As learned from the varied implementation of Medicaid and other state/ federal programs, state efforts can either effectuate or frustrate the intent of health coverage measures. This article is focused on five key implementation issues states face as they turn to new tasks in the governance of Medicaid and private non-group and small group coverage. The Medicaid reforms and the extension of private coverage through Exchanges raise separate challenges. However, as described here, many key implementation issues apply to both systems

    Stabilization of Extra Dimensions at Tree Level

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    By considering the effects of string winding and momentum modes on a time dependent background, we find a method by which six compact dimensions become stabilized naturally at the self-dual radius while three dimensions grow large.Comment: 15 pages, 2 figures, minor typos correcte

    Topology of Entanglement Evolution of Two Qubits

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    The dynamics of a two-qubit system is considered with the aim of a general categorization of the different ways in which entanglement can disappear in the course of the evolution, e.g., entanglement sudden death. The dynamics is described by the function ~n(t), where ~n is the 15-dimensional polarization vector. This representation is particularly useful because the components of ~n are direct physical observables, there is a meaningful notion of orthogonality, and the concurrence C can be computed for any point in the space. We analyze the topology of the space S of separable states (those having C = 0), and the often lower-dimensional linear dynamical subspace D that is characteristic of a specific physical model. This allows us to give a rigorous characterization of the four possible kinds of entanglement evolution. Which evolution is realized depends on the dimensionality of D and of D \cap S, the position of the asymptotic point of the evolution, and whether or not the evolution is "distance-Markovian", a notion we define. We give several examples to illustrate the general principles, and to give a method to compute critical points. We construct a model that shows all four behaviors.Comment: 15 pages, 11 figures, 2 tabl

    The ``Nernst Theorem'' and Black Hole Thermodynamics

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    The Nernst formulation of the third law of ordinary thermodynamics (often referred to as the ``Nernst theorem'') asserts that the entropy, SS, of a system must go to zero (or a ``universal constant'') as its temperature, TT, goes to zero. This assertion is commonly considered to be a fundamental law of thermodynamics. As such, it seems to spoil the otherwise perfect analogy between the ordinary laws of thermodynamics and the laws of black hole mechanics, since rotating black holes in general relativity do not satisfy the analog of the ``Nernst theorem''. The main purpose of this paper is to attempt to lay to rest the ``Nernst theorem'' as a law of thermodynamics. We consider a boson (or fermion) ideal gas with its total angular momentum, JJ, as an additional state parameter, and we analyze the conditions on the single particle density of states, g(ϵ,j)g(\epsilon,j), needed for the Nernst formulation of the third law to hold. (Here, ϵ\epsilon and jj denote the single particle energy and angular momentum.) Although it is shown that the Nernst formulation of the third law does indeed hold under a wide range of conditions, some simple classes of examples of densities of states which violate the ``Nernst theorem'' are given. In particular, at zero temperature, a boson (or fermion) gas confined to a circular string (whose energy is proportional to its length) not only violates the ``Nernst theorem'' also but reproduces some other thermodynamic properties of an extremal rotating black hole.Comment: 20 pages, plain LaTeX fil

    String Gas Cosmology and Structure Formation

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    It has recently been shown that a Hagedorn phase of string gas cosmology may provide a causal mechanism for generating a nearly scale-invariant spectrum of scalar metric fluctuations, without the need for an intervening period of de Sitter expansion. A distinctive signature of this structure formation scenario would be a slight blue tilt of the spectrum of gravitational waves. In this paper we give more details of the computations leading to these results.Comment: 12 pages, 3 figure

    Risk factors associated with adenoma recurrence following cold snare endoscopic mucosal resection of polyps ≥ 20 mm: a retrospective chart review

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    Background and study aims: Cold snare endoscopic mucosal resection (EMR) is being increasingly utilized for non-pedunculated polyps ≥ 20 mm due to adverse events associated with use of cautery. Larger studies evaluating adenoma recurrence rate (ARR) and risk factors for recurrence following cold snare EMR of large polyps are lacking. The aim of this study was to define ARR for polyps ≥ 20 mm removed by cold snare EMR and to identify risk factors for recurrence. Patients and methods: A retrospective chart review of colon cold snare EMR procedures performed between January 2015 and July 2019 at a tertiary care medical center was performed. During this period, 310 non-pedunculated polyps ≥ 20 mm were excised using cold snare EMR with follow-up surveillance colonoscopy. Patient demographic data as well as polyp characteristics at the time of index and surveillance colonoscopy were collected and analyzed. Results: A total of 108 of 310 polyps (34.8 %) demonstrated adenoma recurrence at follow-up colonoscopy. Patients with a higher ARR were older ( P  = 0.008), had endoscopic clips placed at index procedure ( P  = 0.017), and were more likely to be Asian and African American ( P  = 0.02). ARR was higher in larger polyps ( P  \u3c 0.001), tubulovillous adenomas ( P  \u3c 0.001), and polyps with high-grade dysplasia ( P  = 0.003). Conclusions: Although cold snare EMR remains a feasible alternative to hot snare polypectomy for resection of non-pedunculated polyps ≥ 20 mm, endoscopists must also carefully consider factors associated with increased ARR when utilizing this technique

    The Output Gap, the Labor Wedge, and the Dynamic Behavior of Hours

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    We use a standard quantitative business cycle model with nominal price and wage rigidities to estimate two measures of economic ineffciency in recent U.S. data: the output gap - the gap between the actual and effcient levels of output - and the labor wedge - the wedge between households' marginal rate of substitution and firms' marginal product of labor. We establish three results. (i ) The output gap and the labor wedge are closely related, suggesting that most ineffciencies in output are due to the ineffcient allocation of labor. (ii ) The estimates are sensitive to the structural interpretation of shocks to the labor market, which is ambiguous in the model. (iii ) Movements in hours worked are essentially exogenous, directly driven by labor market shocks, whereas wage rigidities generate a markup of the real wage over the marginal rate of substitution that is acyclical. We conclude that the model fails in two important respects: it does not give clear guidance concerning the effciency of business cycle uctuations, and it provides an unsatisfactory explanation of labor market and business cycle dynamics
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