18,066 research outputs found

    Binary Biometric Representation through Pairwise Adaptive Phase Quantization

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    Extracting binary strings from real-valued biometric templates is a fundamental step in template compression and protection systems, such as fuzzy commitment, fuzzy extractor, secure sketch, and helper data systems. Quantization and coding is the straightforward way to extract binary representations from arbitrary real-valued biometric modalities. In this paper, we propose a pairwise adaptive phase quantization (APQ) method, together with a long-short (LS) pairing strategy, which aims to maximize the overall detection rate. Experimental results on the FVC2000 fingerprint and the FRGC face database show reasonably good verification performances.\ud \u

    Targeting the Nrf2-Heme Oxygenase-1 Axis after Intracerebral Hemorrhage.

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    BACKGROUND: Injury to cells adjacent to an intracerebral hemorrhage (ICH) is likely mediated at least in part by toxins released from the hematoma that initiate complex and interacting injury cascades. Pharmacotherapies targeting a single toxin or pathway, even if consistently effective in controlled experimental models, have a high likelihood of failure in a variable clinical setting. Nuclear factor erythroid-2 related factor 2 (Nrf2) regulates the expression of heme oxygenase-1 (HO-1) and multiple other proteins with antioxidant and antiinflammatory effects, and may be a target of interest after ICH. METHODS: Studies that tested the effect of HO and Nrf2 in models relevant to ICH are summarized, with an effort to reconcile conflicting data by consideration of methodological limitations. RESULTS: In vitro studies demonstrated that Nrf2 activators rapidly increased HO-1 expression in astrocytes, and reduced their vulnerability to hemoglobin or hemin. Modulating HO-1 expression via genetic approaches yielded similar results. Systemic treatment with small molecule Nrf2 activators increased HO-1 expression in perivascular cells, particularly astrocytes. When tested in mouse or rat ICH models, Nrf2 activators were consistently protective, improving barrier function and attenuating edema, inflammation, neuronal loss and neurological deficits. These effects were mimicked by selective astrocyte HO-1 overexpression in transgenic mice. CONCLUSION: Systemic treatment with Nrf2 activators after ICH is protective in rodents. Two compounds, dimethyl fumarate and hemin, are currently approved for treatment of multiple sclerosis and acute porphyria, respectively, and have acceptable safety profiles over years of clinical use. Further development of these drugs as ICH therapeutics seems warranted

    Does Where You Live Make You Fat? Obesity and Access to Chain Grocers

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    This paper investigates the role that aspects of the physical environment play in determining health outcomes in adults as measured by body mass index (BMI). Using spatial econometric techniques that allow for spatial spillovers and feedback processes, this research specifically examines how differing levels of access to large chain grocers has on individual health outcomes. While other studies have investigated the impact of proximity to food retailers, the pointcoordinate data used in this paper is uniquely suited to spatial econometric estimation at the individual level. In addition to modeling spatial dependence and allowing for unobserved neighborhood effects, the flexibility of the model is increased by incorporating potential spatial heterogeneity between wealthier and lower-income neighborhoods. Using survey responses tied to geographic location, demographic, behavioral, and access to chain grocers, this study finds evidence of spatial dependence pointing to locational impacts on BMI. The effect on individual health outcomes of retailer access improvements varies depending on neighborhood characteristics. Our findings suggest structural differences in the variation and sensitivity of BMI dependent jointly on individual and neighborhood characteristics.body mass index, obesity, spatial dependence, obesogenic environments

    On Mentzer’s Hardness of the k-Center Problem on the Euclidean Plane.

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    An instance of the k-center problem consists of n points in a metric space along with a positive integer k. The goal is to find the smallest radius r such that there exists a subset of k centers picked among them such that every point is within distance r of at least one center. Stuart Mentzer (Mentzer, 1988) wrote a paper showing that in the Euclidean plane, it is NP-Hard to approximate this problem up to a factor of √2 +√3 ≈ 1.93. However, his report is missing some details. In this note, we present details of his full construction

    Autonomous Demand Side Management Based on Energy Consumption Scheduling and Instantaneous Load Billing: An Aggregative Game Approach

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    In this paper, we investigate a practical demand side management scenario where the selfish consumers compete to minimize their individual energy cost through scheduling their future energy consumption profiles. We propose an instantaneous load billing scheme to effectively convince the consumers to shift their peak-time consumption and to fairly charge the consumers for their energy consumption. For the considered DSM scenario, an aggregative game is first formulated to model the strategic behaviors of the selfish consumers. By resorting to the variational inequality theory, we analyze the conditions for the existence and uniqueness of the Nash equilibrium (NE) of the formulated game. Subsequently, for the scenario where there is a central unit calculating and sending the real-time aggregated load to all consumers, we develop a one timescale distributed iterative proximal-point algorithm with provable convergence to achieve the NE of the formulated game. Finally, considering the alternative situation where the central unit does not exist, but the consumers are connected and they would like to share their estimated information with others, we present a distributed agreement-based algorithm, by which the consumers can achieve the NE of the formulated game through exchanging information with their immediate neighbors.Comment: 11 pages, 7 figure
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