1,104 research outputs found

    Private financing of elder care in Sweden. Arguments for and against

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    The idea that there is a need to increase the share of private financing of the costs of elder care is expressed by several actors attempting to influence the direction of social policy Sweden these days. This idea fundamentally challenges established ways of financing and organising delivery of elder care services in Sweden. Underlying proposals for increasing private financing is the claim that the future scope of public elder care provision must contract, both vertically and horizontally. Underlying this claim is the assumption that both the quantity and quality of services demanded will increase, while the supply of public funds cannot. Vertical contraction aims to draw new funds from users willing to pay more to get higher quality services. Horizontal contraction aims to reduce the scope of public sector’s responsibility in service provision. This paper outlines recent developments in private provision of elder care services and examines arguments and actors for increasing private financing. Although the proposals have been put forward by influential actors, opposition to increasing private financing has been expressed, and support for solidaristic funding of elder care remains strong. Accordingly, we also consider these dissenting arguments and actors. Our purpose is to set out and evaluate the arguments, evidence and interests behind the proposals, and the likely outcomes of their implementation.Elder care; Private financing; Social policy; Sweden;

    Uncertainties and instabilities in celestial mechanics

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    Trajectory optimization using regularized variables

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    Regularized equations for a particular optimal trajectory are compared with unregularized equations with respect to computational characteristics, using perturbation type numerical optimization. In the case of the three dimensional, low thrust, Earth-Jupiter rendezvous, the regularized equations yield a significant reduction in computer time

    Capture of dark matter by the Solar System. Simple estimates

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    We consider the capture of galactic dark matter by the Solar System, due to the gravitational three-body interaction of the Sun, a planet, and a dark matter particle. Simple estimates are presented for the capture cross-section, as well as for density and velocity distribution of captured dark matter particles close to the Earth.Comment: 5 page

    Foundations of multiple black hole evolutions

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    We present techniques for long-term, stable, and accurate evolutions of multiple-black-hole spacetimes using the `moving puncture' approach with fourth- and eighth-order finite difference stencils. We use these techniques to explore configurations of three black holes in a hierarchical system consisting of a third black hole approaching a quasi-circular black-hole binary, and find that, depending on the size of the binary, the resulting encounter may lead to a prompt merger of all three black holes, production of a highly elliptical binary (with the third black hole remaining unbound), or disruption of the binary (leading to three free black holes). We also analyze the classical Burrau three-body problem using full numerical evolutions. In both cases, we find behaviors distinctly different from Newtonian predictions, which has important implications for N-body black-hole simulations. For our simulations we use analytic approximate data. We find that the eighth-order stencils significantly reduce the numerical errors for our choice of grid sizes, and that the approximate initial data produces the expected waveforms (after a rescaling of the puncture masses) for black-hole binaries with modest initial separations.Comment: Revtex 4, 13 pages, 15 figure

    New periodic orbits in the solar sail three-body problem

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    We identify displaced periodic orbits in the circular restricted three-body problem, wher the third (small) body is a solar sail. In particular, we consider solar sail orbits in the earth-sun system which are high above the exliptic plane. It is shown that periodic orbits about surfaces of artificial equilibria are naturally present at linear order. Using the method of Lindstedt-Poincare, we construct nth order approximations to periodic solutions of the nonlinear equations of motion. In the second part of the paper we generalize to the solar sail elliptical restricted three-body problem. A numerical continuation, with the eccentricity, e, as the varying parameter, is used to find periodic orbits above the ecliptic, starting from a known orbit at e=0 and continuing to the requied eccentricity of e=0.0167. The stability of these periodic orbits is investigated

    Orbital Stability of Planets in Binary Systems: A New Look at Old Results

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    About half of all known stellar systems with Sun-like stars consist of two or more stars, significantly affecting the orbital stability of any planet in these systems. This observational evidence has prompted a large array of theoretical research, including the derivation of mathematically stringent criteria for the orbital stability of planets in stellar binary systems, valid for the "coplanar circular restricted three-body problem". In the following, we use these criteria to explore the validity of results from previous theoretical studies.Comment: 3 pages, 1 figure; submitted to: Exoplanets: Detection, Formation and Dynamics, IAU Symposium 249, eds. Y.-S. Sun, S. Ferraz-Mello, and J.-L. Zhou (Cambridge: Cambridge University Press

    `Similar' coordinate systems and the Roche geometry. Application

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    A new equivalence relation, named relation of 'similarity' is defined and applied in the restricted three-body problem. Using this relation, a new class of trajectories (named 'similar' trajectories) are obtained; they have the theoretical role to give us new details in the restricted three-body problem. The 'similar' coordinate systems allow us in addition to obtain a unitary and an elegant demonstration of some analytical relations in the Roche geometry. As an example, some analytical relations published in Astrophysical Journal by Seidov in 2004 are demonstrated.Comment: 9 pages (preprint format), 9 figures, published in Astrophysics and Space Scienc

    Marketization in Long-Term Care: A Cross-Country Comparison of Large For-Profit Nursing Home Chains.

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    This article presents cross-country comparisons of trends in for-profit nursing home chains in Canada, Norway, Sweden, United Kingdom, and the United States. Using public and private industry reports, the study describes ownership, corporate strategies, costs, and quality of the 5 largest for-profit chains in each country. The findings show that large for-profit nursing home chains are increasingly owned by private equity investors, have had many ownership changes over time, and have complex organizational structures. Large for-profit nursing home chains increasingly dominate the market and their strategies include the separation of property from operations, diversification, the expansion to many locations, and the use of tax havens. Generally, the chains have large revenues with high profit margins with some documented quality problems. The lack of adequate public information about the ownership, costs, and quality of services provided by nursing home chains is problematic in all the countries. The marketization of nursing home care poses new challenges to governments in collecting and reporting information to control costs as well as to ensure quality and public accountability

    Extrasolar Planet Interactions

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    The dynamical interactions of planetary systems may be a clue to their formation histories. Therefore, the distribution of these interactions provides important constraints on models of planet formation. We focus on each system's apsidal motion and proximity to dynamical instability. Although only ~25 multiple planet systems have been discovered to date, our analyses in these terms have revealed several important features of planetary interactions. 1) Many systems interact such that they are near the boundary between stability and instability. 2) Planets tend to form such that at least one planet's eccentricity periodically drops to near zero. 3) Mean-motion resonant pairs would be unstable if not for the resonance. 4) Scattering of approximately equal mass planets is unlikely to produce the observed distribution of apsidal behavior. 5) Resonant interactions may be identified through calculating a system's proximity to instability, regardless of knowledge of angles such as mean longitude and longitude of periastron (e.g. GJ 317 b and c are probably in a 4:1 resonance). These properties of planetary systems have been identified through calculation of two parameters that describe the interaction. The apsidal interaction can be quantified by determining how close a planet is to an apsidal separatrix (a boundary between qualitatively different types of apsidal oscillations, e.g. libration or circulation of the major axes). The proximity to instability can be measured by comparing the observed orbital elements to an analytic boundary that describes a type of stability known as Hill stability. We have set up a website dedicated to presenting the most up-to-date information on dynamical interactions: http://www.lpl.arizona.edu/~rory/research/xsp/dynamicsComment: 10 pages, 3 figures, 1 table. To appear in the proceedings of IAU Symposium 249: Exoplanets: Detection, Formation and Dynamics, held in Suzhou, China, Oct 22-26 2007. A version with full resolution figures is available at http://www.lpl.arizona.edu/~rory/publications/bg08a.pd
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