965 research outputs found

    Does cost sharing really reduce inappropriate prescriptions?

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    This paper explores different empirical strategies to examine the effect of cost sharing for prescription drugs in some dimensions of medication-related quality, namely the probability of inappropriate prescription drug use among United States seniors. Using data from 1996 to 2005, we explore various specifications that correct for sample selection, endogeneityž and unobserved heterogeneity. We find a small, but measurable, negative price elasticity for inappropriate drug use with respect to self-reported average out-of-pocket costs for all drugs consumed. That is, user fees reduce the use of potentially inappropriate medications, however the elasticity of cost sharing is lower than that of drugs in general and the price elasticity is relatively close to zero, suggesting that any quality improvements from co-payments are small

    Does Cost Sharing really Reduce Inappropriate Prescriptions?

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    This paper explores different empirical strategies to examine the effect of cost sharing for prescription drugs in some dimensions of medication-related quality, namely the probability of inappropriate prescription drug use among United States seniors. Using data from 1996 to 2005, we explore various specifications that correct for sample selection, endogeneityž and unobserved heterogeneity. We find a small, but measurable, negative price elasticity for inappropriate drug use with respect to self-reported average out-of-pocket costs for all drugs consumed. That is, user fees reduce the use of potentially inappropriate medications, however the elasticity of cost sharing is lower than that of drugs in general and the price elasticity is relatively close to zero, suggesting that any quality improvements from co-payments are small.

    Magnetoresistivity in a Tilted Magnetic Field in p-Si/SiGe/Si Heterostructures with an Anisotropic g-Factor: Part II

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    The magnetoresistance components ρxx\rho_{xx} and ρxy\rho_{xy} were measured in two p-Si/SiGe/Si quantum wells that have an anisotropic g-factor in a tilted magnetic field as a function of temperature, field and tilt angle. Activation energy measurements demonstrate the existence of a ferromagnetic-paramagnetic (F-P) transition for a sample with a hole density of pp=2×1011\times10^{11}\,cm−2^{-2}. This transition is due to crossing of the 0↑\uparrow and 1↓\downarrow Landau levels. However, in another sample, with pp=7.2×1010\times10^{10}\,cm−2^{-2}, the 0↑\uparrow and 1↓\downarrow Landau levels coincide for angles Θ\Theta=0-70o^{\text{o}}. Only for Θ\Theta > 70o^{\text{o}} do the levels start to diverge which, in turn, results in the energy gap opening.Comment: 5 pages, 6 figure

    Study of a Threshold Cherenkov Counter Based on Silica Aerogels with Low Refractive Indices

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    To identify π±\pi^{\pm} and K±K^{\pm} in the region of 1.0∌2.51.0\sim 2.5 GeV/c, a threshold Cherenkov counter equipped with silica aerogels has been investigated. Silica aerogels with a low refractive index of 1.013 have been successfully produced using a new technique. By making use of these aerogels as radiators, we have constructed a Cherenkov counter and have checked its properties in a test beam. The obtained results have demonstrated that our aerogel was transparent enough to make up for loss of the Cherenkov photon yield due to a low refractive index. Various configurations for the photon collection system and some types of photomultipliers, such as the fine-mesh type, for a read out were also tested. From these studies, our design of a Cherenkov counter dedicated to π/K\pi / K separation up to a few GeV/c %in the momentum range of 1.0∌2.51.0 \sim 2.5 GeV/c with an efficiency greater than 9090 \% was considered.Comment: 21 pages, latex format (article), figures included, to be published in Nucl. Instrm. Meth.

    Relativistic confinement of neutral fermions with a trigonometric tangent potential

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    The problem of neutral fermions subject to a pseudoscalar potential is investigated. Apart from the solutions for E=±mc2E=\pm mc^{2}, the problem is mapped into the Sturm-Liouville equation. The case of a singular trigonometric tangent potential (∌tanÎłx\sim \mathrm{tan} \gamma x) is exactly solved and the complete set of solutions is discussed in some detail. It is revealed that this intrinsically relativistic and true confining potential is able to localize fermions into a region of space arbitrarily small without the menace of particle-antiparticle production.Comment: 12 page

    eStorys: A visual storyboard system supporting back-channel communication for emergencies

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    This is the post-print version of the final paper published in Journal of Visual Languages & Computing. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2010 Elsevier B.V.In this paper we present a new web mashup system for helping people and professionals to retrieve information about emergencies and disasters. Today, the use of the web during emergencies, is confirmed by the employment of systems like Flickr, Twitter or Facebook as demonstrated in the cases of Hurricane Katrina, the July 7, 2005 London bombings, and the April 16, 2007 shootings at Virginia Polytechnic University. Many pieces of information are currently available on the web that can be useful for emergency purposes and range from messages on forums and blogs to georeferenced photos. We present here a system that, by mixing information available on the web, is able to help both people and emergency professionals in rapidly obtaining data on emergency situations by using multiple web channels. In this paper we introduce a visual system, providing a combination of tools that demonstrated to be effective in such emergency situations, such as spatio/temporal search features, recommendation and filtering tools, and storyboards. We demonstrated the efficacy of our system by means of an analytic evaluation (comparing it with others available on the web), an usability evaluation made by expert users (students adequately trained) and an experimental evaluation with 34 participants.Spanish Ministry of Science and Innovation and Universidad Carlos III de Madrid and Banco Santander

    The Structure Of The D49 Phospholipase A2 Piratoxin Iii From Bothrops Pirajai Reveals Unprecedented Structural Displacement Of The Calcium-binding Loop: Possible Relationship To Cooperative Substrate Binding

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    Snake venoms are rich sources of phospholipase A2 homologues, both active calcium-binding Asp49 enzymes and essentially inactive Lys49 proteins. They are responsible for multiple pharmacological effects, some of which are dependent on catalytic activity and others of which are not. Here, the 2.4 Å X-ray crystal structure of an active Asp49 phospholipase A2 from the venom of the snake Bothrops pirajai, refined to conventional and free R values of 20.1 and 25.5%, respectively, is reported. Unusually for phospholipases A2, the dependence of the enzyme rate on the substrate concentration is sigmoidal, implying cooperativity of substrate binding. The unprecedented structural distortion seen for the calcium-binding loop in the present structure may therefore be indicative of a T-state enzyme. An explanation of the interaction between the substrate-binding sites based on the canonical phospholipase A2 dimer is difficult. 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    The structure of the D49 phospholipase A(2) piratoxin III from Bothrops pirajai reveals unprecedented structural displacement of the calcium-binding loop: possible relationship to cooperative substrate binding

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    Snake venoms are rich sources of phospholipase A(2) homologues, both active calcium-binding Asp49 enzymes and essentially inactive Lys49 proteins. They are responsible for multiple pharmacological effects, some of which are dependent on catalytic activity and others of which are not. Here, the 2.4 Angstrom X-ray crystal structure of an active Asp49 phospholipase A(2) from the venom of the snake Bothrops pirajai, refined to conventional and free R values of 20.1 and 25.5%, respectively, is reported. Unusually for phospholipases A(2), the dependence of the enzyme rate on the substrate concentration is sigmoidal, implying cooperativity of substrate binding. The unprecedented structural distortion seen for the calcium-binding loop in the present structure may therefore be indicative of a T-state enzyme. An explanation of the interaction between the substrate-binding sites based on the canonical phospholipase A(2) dimer is difficult. However, an alternative putative dimer interface identified in the crystal lattice brings together the calcium-binding loops of neighbouring molecules, along with the C-terminal regions which are disulfide bonded to those loops, thereby offering a possible route of communication between active sites.59225526
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