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Predicting risk of cardiovascular disease using retinal optical coherence tomography imaging

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arXiv 2024年

作者： Maldonado-Garcia, Cynthia Bonazzola, Rodrigo Ferrante, Enzo Julian, Thomas H. Sergouniotis, Panagiotis I. Ravikumar, Nishant Frangi, Alejandro F. Centre for Computational Imaging and Simulation Technologies in Biomedicine School of Computing University of Leeds Leeds United Kingdom CONICET-UNL Santa Fe Argentina Division of Evolution Infection and Genomics School of Biological Sciences Faculty of Biology Medicine and Health University of Manchester Manchester United Kingdom Manchester Royal Eye Hospital Manchester University NHS Foundation Trust Manchester United Kingdom Manchester Centre for Genomic Medicine Saint Mary’s Hospital Manchester University NHS Foundation Trust Manchester United Kingdom Wellcome Genome Campus Cambridge United Kingdom Division of Informatics Imaging and Data Sciences School of Health Sciences Faculty of Biology Medicine and Health University of Manchester Manchester United Kingdom School of Computer Science Faculty of Science and Engineering University of Manchester Kilburn Building Manchester United Kingdom Christabel Pankhurst Institute University of Manchester Manchester United Kingdom NIHR Manchester Biomedical Research Centre Manchester Academic Health Science Centre Manchester United Kingdom

Cardiovascular diseases (CVD) are the leading cause of death globally. Non-invasive, cost-effective imaging techniques play a crucial role in early detection and prevention of CVD. Optical coherence tomography (OCT) has gained recognition as a potential tool for early CVD risk prediction, though its use remains underexplored. In this study, we investigated the potential of OCT as an additional imaging technique to predict future CVD events. We analysed retinal OCT data from the UK Biobank. The dataset included 612 patients who suffered a myocardial infarction (MI) or stroke within five years of imaging and 2,234 controls without CVD (total: 2,846 participants). A self-supervised deep learning approach based on Variational Autoencoders (VAE) was used to extract low-dimensional latent representations from high-dimensional 3D OCT images, capturing distinct features of retinal layers. These latent features, along with clinical data, were used to train a Random Forest (RF) classifier to differentiate between patients at risk of future CVD events (MI or stroke) and healthy controls. Our model achieved an AUC of 0.75, sensitivity of 0.70, specificity of 0.70, and accuracy of 0.70, outperforming the QRISK3 score (the third version of the QRISK cardiovascular disease risk prediction algorithm;AUC = 0.60, sensitivity = 0.60, specificity = 0.55, accuracy = 0.55). The choroidal layer in OCT images was identified as a key predictor of future CVD events, revealed through a novel model explainability approach. This study demonstrates that retinal OCT imaging is a cost-effective, non-invasive alternative for predicting CVD risk, offering potential for widespread application in optometry practices and hospitals. © 2024, CC BY-NC-ND.

关键词： Optical coherence tomography

New bounds and generalizations of locally recoverable codes with availability

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New bounds and generalizations of locally recoverable codes ...

作者： Kruglik, Stanislav Nazirkhanova, Kamilla Frolov, Alexey Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow121205 Russia Department of Radio Engineering and Cybernetics Moscow Institute of Physics and Technology Moscow141701 Russia

We investigate the distance properties of linear locally recoverable codes (LRC codes) with all-symbol locality and availability. New upper and lower bounds on the minimum distance of such codes are derived. The upper bound is based on the shortening method and generalized Hamming weights that are fundamental parameters of any linear codes with many useful applications. This bound improves existing upper bounds. To reduce the gap in between upper and lower bounds, we do not restrict the alphabet size and propose explicit constructions of codes with locality and availability via rank-metric codes. The first construction relies on expander graphs and is better in low rate region. The second construction utilizes the LRC codes developed by Wang et al. as inner codes and is better in high rate region. We also suggest one possible generalization of LRC codes in which the recovering sets can intersect in a small number of coordinates. This feature allows us to increase the achievable code rate and still meet load balancing requirements. We derive upper and lower bounds on the parameters of such codes and present explicit constructions of codes with such a property. © 1963-2012 IEEE.

关键词： Fault tolerance

Estimation of the Second Moment Based on Rounded data

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Journal of Mathematical sciences (United States) 2019年第6期237卷 819-825页

作者： Samsonov, S.V. Ushakov, N.G. Ushakov, V.G. Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow Russian Federation Department of Mathematical Sciences Norwegian University of Science and Technology Trondheim Norway Moscow State University Moscow Russian Federation

Sample moments are unbiased estimators of theoretical moments (if the latter exist). In practice, however, observations are rounded under registration, which leads to systematic errors. In [1–3] it was shown that random measurement errors can provide the reduction of rounding errors, when the expectation is estimated by the first sample moment. This gives a possibility to manage the rounding error of the result, if one can add some noise to observations before registration. Moreover, this error can be made arbitrarily small. Now we find conditions under which this takes place for the second moment. © 2019, Springer science+Business Media, LLC, part of Springer Nature.

关键词： Estimators Registration second moment Noise Systematic errors Error measure Moment of force Rounding error Tea random measurement

Relativistic modified Bessel-Gaussian beam generated from plasma-based beam braiding

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Physical Review A 2021年第2期104卷 L021501-L021501页

作者： Bifeng Lei Daniel Seipt Mingyuan Shi Bin Liu Jingwei Wang Matt Zepf Sergey G. Rykovanov Helmholtz Institute Jena Fröbelstieg 3 07743 Jena Germany GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstrasse 1 64291 Darmstadt Germany Faculty of Physics and Astronomy Friedrich-Schiller-Universität Jena 07743 Jena Germany Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences 201800 Shanghai China Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow 121205 Russia

We theoretically and numerically demonstrate the generation of a relativistic modified Bessel-Gaussian beam (MBGB) via plasma-based beam braiding. It is realized by injecting several intense Gaussian pulses with well-designed offsets and angles into an underdense plasma channel which acts as a laser-pulse combiner via refractive coupling. The MBGB propagates stably in the plasma channel with a well-controlled orbital angular momentum of large value, exciting a twisted plasma wave. After leaving the plasma, it becomes unguided and survives in vacuum for at least hundreds of femtoseconds. This method is insensitive to the initial laser injection conditions and thus should be robust for experimental implementation. It provides an alternative approach in generating high-quality tunable intense optical vortex beams which are desired for various applications.

关键词： Laser driven electron acceleration Laser wakefield acceleration Laser-plasma interactions Plasma acceleration & new acceleration techniques

No-Dealer: Byzantine Fault-Tolerant Random Number Generator

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No-Dealer: Byzantine Fault-Tolerant Random Number Generator

IEEE Conference on Computer Communications Workshops, INFOCOM Wksps

作者： Mikhail Krasnoselskii Grigorii Melnikov Yury Yanovich Moscow Russia Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology (Skoltech) Moscow Russia Laboratory of Data Mining and Predictive Modeling Institute for Information Transmission Problems (IITP RAS) Moscow Russia

The following topics are dealt with: learning (artificial intelligence); Internet of Things; mobile computing; cloud computing; cryptography; telecommunication traffic; data privacy; autonomous aerial vehicles; resour... 详细信息

ISBN: (数字)9781728186955

ISBN: (纸本)9781728186962

关键词： Fault tolerance Fault tolerant systems Protocols Peer-to-peer computing computational modeling Public key

Coding with noiseless feedback over the Z-channel

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arXiv 2020年

作者： Deppe, Christian Lebedev, Vladimir Maringer, Georg Polyanskii, Nikita The Institute for Communications Engineering Technical University of Munich Germany The Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Russia The Institute for Information Transmission Problems Russian Academy of Sciences Russia

In this paper, we consider encoding strategies for the Z-channel with noiseless feedback. We analyze the combinatorial setting where the maximum number of errors inflicted by an adversary is proportional to the number of transmissions, which goes to infinity. Without feedback, it is known that the rate of optimal asymmetric-error-correcting codes for the error fraction τ ≥ 1/4 vanishes as the blocklength grows. In this paper, we give an efficient feedback encoding scheme with n transmissions that achieves a positive rate for any fraction of errors τ Copyright © 2020, The Authors. All rights reserved.

关键词： Signal encoding

Incorruptible Auditing: Blockchain-Powered Graph database Management

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Incorruptible Auditing: Blockchain-Powered Graph Database Ma...

IEEE International Conference on Blockchain and Cryptocurrency (ICBC)

作者： Victor Ermolaev Indrek Klangberg Yash Madhwal Silver Vapper Sjoerd Wels Yury Yanovich Software Department Bitfury Amsterdam The Netherlands Electrical Engineering Mathematics and Computer Science Department University of Twente Enschede The Netherlands Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology (Skoltech) Moscow Russia

ISBN: (数字)9781728166803

ISBN: (纸本)9781728166810

In modern and interconnected world, information is accumulatively stored digitally, making the process of exchanging, gathering and querying the information much easier. Continuously, it has introduced new challenges about how to ensure its consistency and reliability due to the sheer volume of data. A blockchain-based information system can provide an incorruptible record of history, enabling better auditing and data management practices. The paper describes how to combine an Exonum blockchain and a Neo4j graph database into a system that can provide a verifiable audit trail of data integrity and its modifications for information stored in a graph database.

关键词： History Bitcoin Peer-to-peer computing Contracts

Intense harmonics with time-varying orbital angular momentum from relativistic plasma mirrors

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arXiv 2021年

作者： Wang, Jingwei Zepf, Matt Leng, Yuxin Li, Ruxin Rykovanov, Sergey G. Shanghai 201800 China Collaborative Innovation Center of IFSA Shanghai Jiao Tong University Shanghai 200240 China Helmholtz Institute Jena Fröbelstieg 3 Jena07743 Germany Faculty of Physics and Astronomy Friedrich-Schiller-Universität Jena Jena07743 Germany High Performance Computing and Big Data Laboratory Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow121205 Russia

In this Letter using three-dimensional particle-in-cell simulations and analytical considerations we demonstrate intense high-order plasma surface harmonics carrying a time-varying orbital angular momentum (OAM) - the self-torque. We show that by using two laser beams with different OAMs l1 and l2 and a certain delay between each other and shooting them obliquely on an overdense plasma target, one can generate harmonics with OAM spanning nl1 to nl2, where n is the order of the harmonic. Such intense self-torqued harmonics can offer new possibilities in ultrafast spectroscopy. © 2021, CC BY.

关键词： Harmonic analysis

Optimal multistage group testing algorithm for 3 defectives

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arXiv 2020年

作者： Vorobyev, Ilya Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow127051 Russia Advanced Combinatorics and Complex Networks Lab Moscow Institute of Physics and Technology Dolgoprudny141701 Russia

Group testing is a well-known search problem that consists in detecting of s defective members of a set of t samples by carrying out tests on properly chosen subsets of samples. In classical group testing the goal is to find all defective elements by using the minimal possible number of tests in the worst case. In this work, a multistage group testing problem is considered. Our goal is to construct a multistage search procedure, having asymptotically the same number of tests as an adaptive one. We propose a new approach to designing multistage algorithms, which allows us to construct a 5-stage algorithm for finding 3 defectives with the optimal number 3 log2 t(1 + o(1)) of *** Codes 68R05 Copyright © 2020, The Authors. All rights reserved.

关键词： Well testing