672 research outputs found

    Fusing Continuous-valued Medical Labels using a Bayesian Model

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    With the rapid increase in volume of time series medical data available through wearable devices, there is a need to employ automated algorithms to label data. Examples of labels include interventions, changes in activity (e.g. sleep) and changes in physiology (e.g. arrhythmias). However, automated algorithms tend to be unreliable resulting in lower quality care. Expert annotations are scarce, expensive, and prone to significant inter- and intra-observer variance. To address these problems, a Bayesian Continuous-valued Label Aggregator(BCLA) is proposed to provide a reliable estimation of label aggregation while accurately infer the precision and bias of each algorithm. The BCLA was applied to QT interval (pro-arrhythmic indicator) estimation from the electrocardiogram using labels from the 2006 PhysioNet/Computing in Cardiology Challenge database. It was compared to the mean, median, and a previously proposed Expectation Maximization (EM) label aggregation approaches. While accurately predicting each labelling algorithm's bias and precision, the root-mean-square error of the BCLA was 11.78±\pm0.63ms, significantly outperforming the best Challenge entry (15.37±\pm2.13ms) as well as the EM, mean, and median voting strategies (14.76±\pm0.52ms, 17.61±\pm0.55ms, and 14.43±\pm0.57ms respectively with p<0.0001p<0.0001)

    High-Q2Q^2 Elastic eded-scattering and QCD predictions

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    In the framework of pertubative QCD it is argued that in the elastic eded-scattering at Q2∼Q^{2}\sim few (GeV/c)2(GeV/c)^{2} the light-cone-frame helicity-flip amplitudes could not be omitted. The obtained BA\frac{B}{A} ratio of Rosenbluth structure functions is shown to be in a good agreement with experimental data. The high Q2Q^2 behavior of tensor analysing power T20T_{20} is discussed.Comment: 6 pages + 2 ps figures not included, LaTeX, ITP-93-33

    A Survey on Blood Pressure Measurement Technologies: Addressing Potential Sources of Bias

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    Regular blood pressure (BP) monitoring in clinical and ambulatory settings plays a crucial role in the prevention, diagnosis, treatment, and management of cardiovascular diseases. Recently, the widespread adoption of ambulatory BP measurement devices has been driven predominantly by the increased prevalence of hypertension and its associated risks and clinical conditions. Recent guidelines advocate for regular BP monitoring as part of regular clinical visits or even at home. This increased utilization of BP measurement technologies has brought up significant concerns, regarding the accuracy of reported BP values across settings. In this survey, focusing mainly on cuff-based BP monitoring technologies, we highlight how BP measurements can demonstrate substantial biases and variances due to factors such as measurement and device errors, demographics, and body habitus. With these inherent biases, the development of a new generation of cuff-based BP devices which use artificial-intelligence (AI) has significant potential. We present future avenues where AI-assisted technologies can leverage the extensive clinical literature on BP-related studies together with the large collections of BP records available in electronic health records. These resources can be combined with machine learning approaches, including deep learning and Bayesian inference, to remove BP measurement biases and to provide individualized BP-related cardiovascular risk indexes

    Scaling law for the electromagnetic form factors of the proton

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    The violation of the scaling law for the electric and magnetic form factors of the proton are examined within the cloudy bag model. The suppression of the ratio of the electric and magnetic form factors is natural in the bag model. The pion cloud plays a moderate role in understanding the recent data from TJNAF.Comment: 8 pages, REVTeX, 2 figures include
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