1,966 research outputs found

    Generalized Bayesian Record Linkage and Regression with Exact Error Propagation

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    Record linkage (de-duplication or entity resolution) is the process of merging noisy databases to remove duplicate entities. While record linkage removes duplicate entities from such databases, the downstream task is any inferential, predictive, or post-linkage task on the linked data. One goal of the downstream task is obtaining a larger reference data set, allowing one to perform more accurate statistical analyses. In addition, there is inherent record linkage uncertainty passed to the downstream task. Motivated by the above, we propose a generalized Bayesian record linkage method and consider multiple regression analysis as the downstream task. Records are linked via a random partition model, which allows for a wide class to be considered. In addition, we jointly model the record linkage and downstream task, which allows one to account for the record linkage uncertainty exactly. Moreover, one is able to generate a feedback propagation mechanism of the information from the proposed Bayesian record linkage model into the downstream task. This feedback effect is essential to eliminate potential biases that can jeopardize resulting downstream task. We apply our methodology to multiple linear regression, and illustrate empirically that the "feedback effect" is able to improve the performance of record linkage.Comment: 18 pages, 5 figure

    Suppression of geometrical barrier in Bi2Sr2CaCu2O8+δBi_2Sr_2CaCu_2O_{8+\delta} crystals by Josephson vortex stacks

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    Differential magneto-optics are used to study the effect of dc in-plane magnetic field on hysteretic behavior due to geometrical barriers in Bi2Sr2CaCu2O8+δBi_2Sr_2CaCu_2O_{8+\delta} crystals. In absence of in-plane field a vortex dome is visualized in the sample center surrounded by barrier-dominated flux-free regions. With in-plane field, stacks of Josephson vortices form vortex chains which are surprisingly found to protrude out of the dome into the vortex-free regions. The chains are imaged to extend up to the sample edges, thus providing easy channels for vortex entry and for drain of the dome through geometrical barrier, suppressing the magnetic hysteresis. Reduction of the vortex energy due to crossing with Josephson vortices is evaluated to be about two orders of magnitude too small to account for the formation of the protruding chains. We present a model and numerical calculations that qualitatively describe the observed phenomena by taking into account the demagnetization effects in which flux expulsion from the pristine regions results in vortex focusing and in the chain protrusion. Comparative measurements on a sample with narrow etched grooves provide further support to the proposed model.Comment: 12 figures (low res.) Higher resolution figures are available at the Phys Rev B version. Typos correcte

    STROZ Lidar Results at the MOHAVE III Campaign, October, 2009, Table Mountain, CA

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    During October, 2009 the GSFC STROZ Lidar participated in a campaign at the JPL Table Mountain Facility (Wrightwood, CA, 2285 m Elevation) to measure vertical profiles of water vapor from near the ground to the lower stratosphere. On eleven nights, water vapor, aerosol, temperature and ozone profiles were measured by the STROZ lidar, two other similar lidars, frost-point hygrometer sondes, and ground-based microwave instruments made measurements. Results from these measurements and an evaluation of the performance of the STROZ lidar during the campaign will be presented in this paper. The STROZ lidar was able to measure water vapor up to 13-14 km ASL during the campaign. We will present results from all the STROZ data products and comparisons with other instruments made. Implications for instrumental changes will be discussed

    Denaturation of Heterogeneous DNA

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    The effect of heterogeneous sequence composition on the denaturation of double stranded DNA is investigated. The resulting pair-binding energy variation is found to have a negligible effect on the critical properties of the smooth second order melting transition in the simplest (Peyrard-Bishop) model. However, sequence heterogeneity is dramatically amplified upon adopting a more realistic treatment of the backbone stiffness. The model yields features of ``multi-step melting'' similar to those observed in experiments.Comment: 4 pages, LaTeX, text and figures also available at http://matisse.ucsd.edu/~hw

    The Effect of Air on Granular Size Separation in a Vibrated Granular Bed

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    Using high-speed video and magnetic resonance imaging (MRI) we study the motion of a large sphere in a vertically vibrated bed of smaller grains. As previously reported we find a non-monotonic density dependence of the rise and sink time of the large sphere. We find that this density dependence is solely due to air drag. We investigate in detail how the motion of the intruder sphere is influenced by size of the background particles, initial vertical position in the bed, ambient pressure and convection. We explain our results in the framework of a simple model and find quantitative agreement in key aspects with numerical simulations to the model equations.Comment: 14 pages, 16 figures, submitted to PRE, corrected typos, slight change

    Boson-assisted tunneling in layered metals

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    A theory for boson-assisted tunneling via randomly distributed resonant states in a layered metals is developed. As particular examples, we consider the electron-phonon interaction and the interaction between localized and conduction electrons. The theory is applied to explain a non-monotonic variation of the out-plane resistivity with temperature observed in quasi-two-dimensional metals.Comment: 14 pages, 5 figure

    Invariant construction of solutions to Einstein's field equations - LRS perfect fluids II

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    The properties of LRS class II perfect fluid space-times are analyzed using the description of geometries in terms of the Riemann tensor and a finite number of its covariant derivatives. In this manner it is straightforward to obtain the plane and hyperbolic analogues to the spherical symmetric case. For spherically symmetric static models the set of equations is reduced to the Tolman-Oppenheimer-Volkoff equation only. Some new non-stationary and inhomogeneous solutions with shear, expansion, and acceleration of the fluid are presented. Among these are a class of temporally self-similar solutions with equation of state given by p=(γ−1)μ,1<γ<2p=(\gamma-1)\mu, 1<\gamma<2, and a class of solutions characterized by σ=−Θ/6\sigma=-\Theta/6. We give an example of geometry where the Riemann tensor and the Ricci rotation coefficients are not sufficient to give a complete description of the geometry. Using an extension of the method, we find the full metric in terms of curvature quantities.Comment: 24 pages, 1 figur

    WHO-ISG collaboration on assistive technologies for healthy ageing-in-place:A round table discussion

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    Assistive Technology (AT) is used at various points in the lifespan by those coping with either short-term or long-term impairments, which can involve living with chronic conditions and/or comorbidities. In the case of older adults, AT can support or compensate for the functional or cognitive declines that they are likely to face in later life. AT can be integrated as part of smart homes (see Figure 1 from van Dijken et al, 2006); and should be safe to use, effective, easy to access, affordable, and not seen as stigmatising. In addition, AT should support older adults to have a meaningful life while building self-esteem, and autonomy and promoting social participation and community engagement. For this roundtable discussion, we present and discuss a WHO-ISG collaborative project focused on Assistive Technology for Healthy Ageing. For this project, we consider applications and use AT not only from a medical standpoint but also situated within a social perspective in the context of Gerontechnology. Results and propositions according to the WHO-UNICEF global report on assistive technology were applied as a starting point for this project (WHO, 2022), prioritising the potential benefits to individuals, their communities, and society and with a focus on identifying potential barriers that may occur and how to mitigate them

    Leiomyosarcoma of the breast in a patient with a 10-year-history of cyclophosphamide exposure: a case report

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    A 50 year old woman with a 10-year history of systemic lupus erythematosus (SLE) and intermittent low-dose cyclophosphamide therapy developed a palpable mass at the periphery of her left breast. Ultrasound guided core biopsy revealed a spindle cell neoplasm characterized on final pathology as a low grade leiomyosarcoma
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