751 research outputs found

    Financial Information Mediation: A Case Study of Standards Integration for Electronic Bill Presentment and Payment Using the COIN Mediation Technology

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    Each player in the financial industry, each bank, stock exchange, government agency, or insurance company operates its own financial information system or systems. By its very nature, financial information, like the money that it represents, changes hands. Therefore the interoperation of financial information systems is the cornerstone of the financial services they support. E-services frameworks such as web services are an unprecedented opportunity for the flexible interoperation of financial systems. Naturally the critical economic role and the complexity of financial information led to the development of various standards. Yet standards alone are not the panacea: different groups of players use different standards or different interpretations of the same standard. We believe that the solution lies in the convergence of flexible E-services such as web-services and semantically rich meta-data as promised by the semantic Web; then a mediation architecture can be used for the documentation, identification, and resolution of semantic conflicts arising from the interoperation of heterogeneous financial services. In this paper we illustrate the nature of the problem in the Electronic Bill Presentment and Payment (EBPP) industry and the viability of the solution we propose. We describe and analyze the integration of services using four different formats: the IFX, OFX and SWIFT standards, and an example proprietary format. To accomplish this integration we use the COntext INterchange (COIN) framework. The COIN architecture leverages a model of sources and receivers’ contexts in reference to a rich domain model or ontology for the description and resolution of semantic heterogeneity.Singapore-MIT Alliance (SMA

    Radiative acceleration and transient, radiation-induced electric fields

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    The radiative acceleration of particles and the electrostatic potential fields that arise in low density plasmas hit by radiation produced by a transient, compact source are investigated. We calculate the dynamical evolution and asymptotic energy of the charged particles accelerated by the photons and the radiation-induced electric double layer in the full relativistic, Klein-Nishina regime. For fluxes in excess of 102710^{27} ergcm2s1{\rm erg} {\rm cm}^{-2} {\rm s}^{-1}, the radiative force on a diluted plasma (n\la 10^{11} cm3^{-3}) is so strong that electrons are accelerated rapidly to relativistic speeds while ions lag behind owing to their larger inertia. The ions are later effectively accelerated by the strong radiation-induced double layer electric field up to Lorentz factors 100\approx 100, attainable in the case of negligible Compton drag. The asymptotic energies achieved by both ions and electrons are larger by a factor 2--4 with respect to what one could naively expect assuming that the electron-ion assembly is a rigidly coupled system. The regime we investigate may be relevant within the framework of giant flares from soft gamma-repeaters.Comment: 14 pages, 7 figures, ApJ, in press (tentatively scheduled for the v. 592, 2003 issue

    Force-Free Models of Magnetically Linked Star-Disk Systems

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    Disk accretion onto a magnetized star occurs in a variety of astrophysical contexts, from young stars to X-ray pulsars. The magnetohydrodynamic interaction between the stellar field and the accreting matter can have a strong effect on the disk structure, the transfer of mass and angular momentum between the disk and the star, and the production of bipolar outflows, e.g., plasma jets. We study a key element of this interaction - the time evolution of the magnetic field configuration brought about by the relative rotation between the disk and the star - using simplified, largely semianalytic, models. We first discuss the rapid inflation and opening up of the magnetic field lines in the corona above the accretion disk, which is caused by the differential rotation twisting. Then we consider additional physical effects that tend to limit this expansion, such as the effect of plasma inertia and the possibility of reconnection in the disk's corona, the latter possibly leading to repeated cycles in the evolution. We also derive the condition for the existence of a steady state for a resistive disk and conclude that a steady state configuration is not realistically possible. Finally, we generalize our analysis of the opening of magnetic field lines by using a non-self-similar numerical model that applies to an arbitrarily rotating (e.g. keplerian) disk.Comment: 75 pages, 22 figures, 2 tables. Submitted to Astrophysical Journa

    Nationally representative trends and geographic variation in treatment of localized prostate cancer: the Urologic Diseases in America project

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    BACKGROUND: Several treatment options for clinically localized prostate cancer currently exist under the established guidelines. We aim to assess nationally representative trends in treatment over time and determine potential geographic variation using two large national claims registries. METHODS: Men with prostate cancer insured by Medicare (1998-2006) or a private insurer (Ingenix database, 2002-2006) were identified using International Classification of Diseases-9 and Current Procedural Terminology-4 codes. Geographic variation and trends in the type of treatment utilized over time were assessed. Geographic data were mapped using the GeoCommons online mapping platform. Predictors of any treatment were determined using a hierarchical generalized linear mixed model using the logit link function. RESULTS: The use of radical prostatectomy increased, 33-48%, in the privately insured i3 database while remaining stable at 12% in the Medicare population. There was a rapid uptake in the use of newer technologies over time in both the Medicare and i3 cohorts. The use of laparoscopic-assisted prostatectomy increased from 1% in 2002 to 41% in 2006 in i3 patients, whereas the incidence increased from 3% in 2002 to 35% in 2006 for Medicare patients. The use of neoadjuvant/adjuvant androgen deprivation therapy was lower in the i3 cohort and has decreased over time in both i3 and Medicare. Physician density had an impact on the type of primary treatment received in the New England region; however, this trend was not seen in the western or southern regions of the United States. CONCLUSIONS: Using two large national claims registries, we have demonstrated trends over time and substantial geographic variation in the type of primary treatment used for localized prostate cancer. Specifically, there has been a large increase in the use of newer technologies (that is, laparoscopic-assisted prostatectomy and intensity-modulated radiation therapy). These results elucidate the need for improved data collection on prostate cancer treatment outcomes to reduce unwarranted variation in care

    Relating the Kick Velocities of Young Pulsars with Magnetic Field Growth Timescales Inferred From Braking Indices

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    A nascent neutron star may be exposed to fallback accretion soon after the proto-neutron star stage. This high accretion episode can submerge the magnetic field deep in the crust. The diffusion of the magnetic field back to the surface will take hundreds to millions of years depending on the amount of mass accreted and the consequent depth the field is buried. Neutron stars with large kick velocities will accrete less amount of fallback material leading to shallower submergence of their fields and shorter time-scales for the growth of their fields. We obtain the relation τOhmv1\tau_{\rm Ohm} \propto v^{-1} between the space velocity of the neutron star and Ohmic time-scale for the growth of the magnetic field. We compare this with the relation between the measured transverse velocities, vv_{\perp} and the field growth time-scales, μ/μ˙\mu/\dot{\mu}, inferred from the measured braking indices. We find that the observational data is consistent with the theoretical prediction though the small number of data precludes a strong conclusion. Measurement of the transverse velocities of pulsars B1509-58, J1846-0258, J1119-6127 and J1734-3333 would increase the number of the data and strongly contribute to understanding whether pulsar fields grow following fallback accretion.Comment: Accepted to MNRAS Letters. Title and abstract are change

    Rethinking Work and Family Policy: The Making and Taking of Parental Leave in Australia

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    Despite the continued increase in female participation rates, Australia remains one of only two developed nations in the world without a paid maternity leave scheme. While research interest and public policy debate about paid maternity leave entitlements continues, little is known about the actual utilization of the 52 weeks unpaid parental leave that is currently available to all employees. Moreover, research and policy debate on the availability and provision of paid paternity leave has only just begun. This paper argues that, given the gendered nature of employee entitlements, it is time to re-evaluate all aspects of parental leave policy in Australia. Using unique data from a national survey of Australian employees, the paper provides a statistical analysis of the use of unpaid parental leave and the availability of paid maternity leave. The paper models the availability of paid maternity leave to Australian employees as a function of demographic and organizational characteristics, including annual income, union status, and establishment size. A parallel analysis of the likelihood that an individual has used the unpaid parental leave provision is also provided. The results show that the existing unpaid parental leave provision is rarely used and that the current availability of paid maternity leave is inequitable. The paper discusses the conceptual and policy implications of these results and concludes that a re-thinking of parental leave policy in Australia is essential if gender inequities at work and in society are to be addressed

    Marrow angiogenesis-associated factors as prognostic biomarkers in patients with acute myelogenous leukaemia

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    Bone marrow (BM) neoangiogenesis plays an important role in acute myelogenous leukaemia (AML), and depends on the interplay of members of the vascular endothelial growth factor (VEGF) and angiopoietin (Ang) families. We determined the marrow levels of seven molecules associated with angiogenesis in 52 AML patients before chemotherapy and 20 healthy controls: VEGF-A, VEGF/PlGF, VEGF-C, VEGF-D, Ang-1, Ang-2, and Tie-2. All the molecules were quantified using enzyme-linked immunosorbent assay (ELISA). Comparing to normal controls, the marrow levels of VEGF/PlGF, Ang-2, and Tie-2 were significantly higher, and those of VEGF-C and Ang-1 were significantly lower in the AML patients (P<0.001). A total of 31 patients were further subjected to survival analysis. Patients with lower Tie-2 (<26 ng ml−1) and Ang-2 levels (<4500 pg ml−1) displayed a survival advantage (P=0.037 and 0.042, respectively), same as patients with higher VEGF/PlGF (⩾1 pg ml−1) and VEGF-D levels (⩾350 pg ml−1) (P=0.020 and 0.016, respectively). An angio-index ((Ang-2 × Tie-2)/(VEGF/PlGF × VEGF-D)) was established and multivariate Cox regression analysis revealed that patients with higher angio-index values (⩾50) displayed poor prognosis (hazard ratio 5.91, 95% confidence interval 1.99–17.56; P=0.001). The angio-index is closely associated with the clinical outcome of AML patients and may be valuable in disease prognosis
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