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Emergence of the First Strains of SARS-CoV-2 Lineage B.1.1.7 in Romania: Genomic Analysis

JMIRx med 2021年第3期2卷 e28049页

作者： Andrei Lobiuc Mihai Dimian Olga Sturdza Roxana Filip Mihai Covasa Department of Human Health and Development College of Physical Exercise and Sport Stefan cel Mare University of Suceava Suceava Romania. Department of Computers Electronics and Automation College of Electrical Engineering and Computer Science Stefan cel Mare University of Suceava Suceava Romania. Integrated Center for Research Development and Innovation in Advanced Materials Nanotechnologies and Distributed Systems for Fabrication and Control Stefan cel Mare University of Suceava Suceava Romania. Suceava County Emergency Hospital Suceava Romania.

BACKGROUND:The United Kingdom reported the emergence of a new and highly transmissible SARS-CoV-2 variant (B.1.1.7) that rapidly spread to other countries. The impact of this new mutation-which occurs in the S protein-on infectivity, virulence, and current vaccine effectiveness is still under evaluation. OBJECTIVE:The aim of this study is to sequence SARS-CoV-2 samples of cases in Romania to detect the B.1.1.7 variant and compare these samples with sequences submitted to GISAID. METHODS:SARS-CoV-2 samples were sequenced and amino acid substitution analysis was performed using the CoV-GLUE platform. RESULTS:We have identified the first cases of the B.1.1.7 variant in samples collected from Romanian patients, of which one was traced to the region of the United Kingdom where the new variant was originally sequenced. Mutations in nonstructural protein 3 (Nsp3; N844S and D455N) and ORF3a (L15F) were also detected, indicating common ancestry with UK strains as well as remote connections with strains from Nagasaki, Japan. CONCLUSIONS:These results indicate, for the first time, the presence and characteristics of the new variant B.1.1.7 in Romania and underscore the need for increased genomic sequencing in patients with confirmed COVID-19.

关键词： COVID-19 Romania case study epidemiology genetics genome impact infectious disease lineage mutation sequencing spread strain transmission variant virology virus

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Robust medical instrument segmentation challenge 2019

arXiv

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arXiv 2020年

作者： Roβ, Tobias Reinke, Annika Full, Peter M. Wagner, Martin Kenngott, Hannes Apitz, Martin Hempe, Hellena Filimon, Diana Mindroc Scholz, Patrick Tran, Thuy Nuong Bruno, Pierangela Arbelaéz, Pablo Bian, Gui-Bin Bodenstedt, Sebastian Bolmgren, Jon Lindström Bravo-Sánchez, Laura Chen, Hua-Bin González, Cristina Guo, Dong Halvorsen, Pål Heng, Pheng-Ann Hosgor, Enes Hou, Zeng-Guang Isensee, Fabian Jha, Debesh Jiang, Tingting Kirtac, Kadir Jin, Yueming Kletz, Sabrina Leger, Stefan Li, Zhixuan Maier-Hein, Klaus H. Ni, Zhen-Liang Riegler, Michael A. Schoeffmann, Klaus Shi, Ruohua Speidel, Stefanie Stenze, Michael Twick, Isabell Wang, Gutai Wang, Jiacheng Wang, Liansheng Wang, Lu Zhang, Yujie Zhou, Yan-Jie Zhu, Lei Wiesenfarth, Manuel Kopp-Schneider, Annette Müller-Stich, Beat P. Maier-Hein, Lena Heidelberg Germany University of Heidelberg Germany Heidelberg Germany Department of General Heidelberg University Hospital Visceral and Transplant Surgery Heidelberg Germany caresyntax Berlin Germany University of Chinese Academy Sciences Beijing China State Key Laboratory of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences Beijing China SimulaMet Oslo Norway Tromsø Norway Oslo Norway School of Mechanical and Electrical Engineering University of Electronic Science and Technology of China Chengdu China Partner Site Dresden Heidelberg Germany Faculty of Medicine and University Hospital Carl Gustav Carus Technische Universität Dresden Dresden Germany Dresden Germany Universidad de Los Andes Bogotá Colombia Peking University Peking China Department of Computer Science School of Informatics Xiamen University Xiamen China Department of Computer Science and Engineering Chinese University of Hong Kong Hong Kong German Cancer Research Center Division of Biostatistics Heidelberg Germany Institute of Information Technology Klagenfurt University Austria

Intraoperative tracking of laparoscopic instruments is often a prerequisite for computer and roboticassisted interventions. While numerous methods for detecting, segmenting and tracking of medical instruments based on endoscopic video images have been proposed in the literature, key limitations remain to be addressed: Firstly, robustness, that is, the reliable performance of state-of-the-art methods when run on challenging images (e.g. in the presence of blood, smoke or motion artifacts). Secondly, generalization;algorithms trained for a specific intervention in a specific hospital should generalize to other interventions or institutions. In an effort to promote solutions for these limitations, we organized the Robust Medical Instrument Segmentation (ROBUST-MIS) challenge as an international benchmarking competition with a specific focus on the robustness and generalization capabilities of algorithms. For the first time in the field of endoscopic image processing, our challenge included a task on binary segmentation and also addressed multi-instance detection and segmentation. The challenge was based on a surgical data set comprising 10,040 annotated images acquired from a total of 30 surgical procedures from three different types of surgery. The validation of the competing methods for the three tasks (binary segmentation, multi-instance detection and multi-instance segmentation) was performed in three different stages with an increasing domain gap between the training and the test data. The results confirm the initial hypothesis, namely that algorithm performance degrades with an increasing domain gap. While the average detection and segmentation quality of the best-performing algorithms is high, future research should concentrate on detection and segmentation of small, crossing, moving and transparent instrument(s) (parts). Copyright © 2020, The Authors. All rights reserved.

关键词： Endoscopy

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Assessment of plant structural characteristics, health, and ecology using bioacoustic tools 175

Assessment of plant structural characteristics, health, and ...

引用

175th Meeting of the Acoustical Society of America

作者： Mankin, Richard W. Stanaland, Daniel Haseeb, Muhammad Rohde, Barukh Menocal, Octavio Carrillo, Daniel Center for Med. Agric. Veterinary Entomol. United States Department of Agriculture-ARS GainesvilleFL32607 United States Center for Biological Control FAMU TallahasseeFL32307 United States FAMU TallahasseeFL32307 United States Electrical and Computer Engineering University of Florida GainesvilleFL32611 United States Tropical Research and Education Center University of Florida HomesteadFL33031 United States

Plants have responded to abiotic stress and biotic threats with evolutionary adaptations resulting in a variety of plant architectures and cell walls with economically important mechanical properties. Bioacoustic tools have been applied to measure mechanical properties of plant structures, optimize mechanical harvesting, and detect the distribution of root systems, as well as to monitor plant health, photosynthesis, and ecology, and to assess the quality of marketable plant products. In addition, acoustic and vibration sensors are used by entomologists to detect hidden infestations of invasive insect species and to monitor insect movement, feeding, and mating activities on host plants. Reliable identification and interpretation of insect-produced sounds and vibrations on and within plants is complicated by physical processes that filter and distort vibrations as they pass through and reflect from different plant structures and the air. This report considers the use of bioacoustic tools to analyze plant health and structural characteristics, and then discusses how combinations of spectral-, temporal-, and spatial-distribution features of signals detected in plants can be interpreted in ways that properly account for plant structural vibrational filtering and distortion processes and enable reliable assessment of hidden pest infestations, including invasive insect species of importance for plant biosecurity. © 2018 Acoustical Society of America.

关键词： Vibration analysis

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Distributed Resource Allocation through Utility Design – Part I: Optimizing the Performance Certificates via the Price of Anarchy

arXiv

引用

arXiv 2018年

作者： Paccagnan, Dario Chandan, Rahul Marden, Jason R. Mechanical Engineering Department Center of Control Dynamical Systems and Computation UC Santa BarbaraCA93106-5070 United States Department of Electrical and Computer Engineering University of California Santa BarbaraCA93106-5070 United States

—Game theory has emerged as a fruitful paradigm for the design of networked multiagent systems. A fundamental component of this approach is the design of agents’ local utility functions so that their self-interested maximization results in a desirable collective behavior. In this work we focus on a well-studied class of distributed resource allocation problems where each agent is requested to select a subset of resources with the goal of optimizing a given system-level objective, separable over the resources. Our core contribution is the development of a novel framework to tightly characterize the worst case performance of any resulting Nash equilibrium (price of anarchy) as a function of the chosen agents’ utility functions. Leveraging this result, we then identify how to design such utilities so as to optimize the price of anarchy through a tractable linear program. This provides us with a-priori performance certificates applicable to any existing learning algorithm capable of driving the system to an equilibrium. Part II of this work specializes these results to submodular and supermodular objectives, discusses the complexity of computing Nash equilibria, and provides multiple illustrations of the theoretical findings. Copyright © 2018, The Authors. All rights reserved.

关键词： Game theory

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Distributed resource allocation through utility design - Part II: Applications to submodular, supermodular and set covering problems

arXiv

引用

arXiv 2018年

作者： Paccagnan, Dario Marden, Jason R. Mechanical Engineering Department Center of Control Dynamical Systems and Computation UC Santa Barbara CA93106-5070 United States Department of Electrical and Computer Engineering University of California Santa BarbaraCA93106-5070 United States

A fundamental component of the game theoretic approach to distributed control is the design of local utility functions. In Part I of this work we showed how to systematically design local utilities so as to maximize the induced worst case performance. The purpose of the present manuscript is to specialize the general results obtained in Part I to a class of monotone submodular, supermodular and set covering problems. In the case of set covering problems, we show how any distributed algorithm capable of computing a Nash equilibrium inherits a performance certificate matching the well known 1 - 1=e approximation of [1]. Relative to the class of submodular maximization problems considered here, we show how the performance offered by the game theoretic approach improves on existing approximation algorithms. We briefly discuss the algorithmic complexity of computing (pure) Nash equilibria and show how our approach generalizes and subsumes previously fragmented results in the area of optimal utility design. Two applications and corresponding numerics are presented: the vehicle target assignment problem and a coverage problem arising in distributed caching for wireless networks. Copyright © 2018, The Authors. All rights reserved.

关键词： Combinatorial optimization

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Semi-global leader-following output consensus of discrete-time linear multi-agent systems with input saturation

Semi-global leader-following output consensus of discrete-ti...

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2018 IEEE International Conference on Real-Time Computing and Robotics, RCAR 2018

作者： Shi, Liangren Li, Yuanlong Lin, Zongli Brown, Charles L. Innovation Center Department of Automation Shanghai Jiao Tong University China Key Laboratory of System Control and Information Processing Ministry of Education Shanghai200240 China Department of Automation Shanghai Jiao Tong University China Department of Electrical and Computer Engineering University of Virginia P.O. Box 400743 CharlottesvilleVA22904-4743 United States

ISBN: (纸本)9781538668689

We consider the problem of semi-global leader-following output consensus for a group of agents, consisting of a leader agent and some follower agents, which are described by discrete-time linear systems and connected on a directed network. For each follower agent, a distributed observer is built that estimates the state of the leader. Based on the estimates of the leader state and the solution of a parameterized algebraic Riccati equation, we design low gain consensus protocols that are shown to solve the semi-global output consensus problem as long as the leader agent is reachable globally on the network. Numerical simulation shows the performance of the proposed consensus protocols. © 2018 IEEE.

关键词： Multi agent systems

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Secure quantum key distribution with realistic devices

arXiv

引用

arXiv 2019年

作者： Xu, Feihu Ma, Xiongfeng Zhang, Qiang Lo, Hoi-Kwong Pan, Jian-Wei Hefei National Laboratory for Physical Sciences at Microscale Department of Modern Physics University of Science and Technology of China Hefei230026 China Shanghai Branch CAS Center for Excellence Synergetic Innovation Center in Quantum Information and Quantum Physics University of Science and Technology of China Shanghai201315 China Center for Quantum Information Institute for Interdisciplinary Information Sciences Tsinghua University Beijing100084 China Center for Quantum Information and Quantum Control Department of Physics Department of Electrical & Computer Engineering University of Toronto TorontoM5S 3G4 Canada

In principle, quantum key distribution (QKD) offers information-theoretic security based on the laws of physics. In practice, however, the imperfections of realistic devices might introduce deviations from the idealized models used in security analyses. Can quantum code-breakers successfully hack real systems by exploiting the side channels? Can quantum code-makers design innovative counter-measures to foil quantum code-breakers? This article reviews theoretical and experimental progress in the practical security aspects of quantum code-making and quantum code-breaking. After numerous attempts, researchers now thoroughly understand and are able to manage the practical imperfections. Recent advances, such as the measurement-device-independent protocol, have closed the critical side channels in the physical implementations, paving the way for secure QKD with realistic devices. Copyright © 2019, The Authors. All rights reserved.

关键词： Quantum cryptography

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Robust ADRC for Nonlinear Time-varying System with Uncertainties 6

Robust ADRC for Nonlinear Time-varying System with Uncertain...

引用

2017 IEEE 6th Data Driven control and Learning Systems Conference (DDCLS’17)

作者： Xiangyang Li Wei Ai Zhiqiang Gao Senping Tian Key Laboratory of Autonomous Systems and Networked Control Ministry of Education School of Automation Science and Engineering South China University of Technology IEEE Center for Advanced Control Technologies Department of Electrical and Computer EngineeringCleveland State University

ISBN: (纸本)9781509054626

Active disturbance rejection control(ADRC) exemplifies the spirit of the data-driven control(DDC) design strategy and shows much promise in obtaining consistent applications in industrial control systems with uncertainties, without the premise that the detailed mathematical model of the controlled system is given. Instead, it is shown that the information needed for the control system to work at high level of effectiveness can be extracted from the input-output data by the use of the extended state observer(ESO). On the other hand, it is shown in this paper that the robustness of ADRC depends on the effectiveness of ESO. Furthermore, taking advantage of the rich body of knowledge in the existing field of robust control, the estimation error in ESO is analysed and, for the purpose of improved robustness, a unique nonlinear component is added to the conventional ADRC law. The modified ADRC which is a kind of robust ADRC law is validated in simulation for a nonlinear time-varying system with parametric and functional uncertainties. It is shown that the proposed robust ADRC law provides more effective tracking performance than the conventional ADRC when the bandwidth of ESO is not wide enough.

关键词： Active Disturbance Rejection control(ADRC) Robust control Extended State Observer(ESO) Nonlinear Time-varying System

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Improved boltzmann machines with error corrected quantum annealing

arXiv

引用

arXiv 2019年

作者： Li, Richard Y. Albash, Tameem Lidar, Daniel A. Department of Chemistry University of Southern California Los AngelesCA90089 United States Center for Quantum Information Science and Technology University of Southern California Los AngelesCA90089 United States Department of Electrical and Computer Engineering University of New Mexico AlbuquerqueNM87131 United States Department of Physics and Astronomy University of New Mexico AlbuquerqueNM87131 United States Center for Quantum Information and Control University of New Mexico AlbuquerqueNM87131 United States Department of Physics and Astronomy University of Southern California Los AngelesCA90089 United States Department of Electrical Engineering University of Southern California Los AngelesCA90089 United States

Boltzmann machines, a class of machine learning models, are the basis of several deep learning methods that have been successfully applied to both supervised and unsupervised machine learning tasks. These models assume that some given dataset is generated according to a Boltzmann distribution, and the goal of the training procedure is to learn the set of parameters that most closely match the input data distribution. Training such models is difficult due to the intractability of traditional sampling techniques, and proposals using quantum annealers for sampling hope to mitigate the cost associated with sampling. However, real physical devices will inevitably be coupled to the environment, and the strength of this coupling affects the effective temperature of the distributions from which a quantum annealer samples. To counteract this problem, error correction schemes that can effectively reduce the temperature are needed if there is to be some benefit in using quantum annealing for problems at a larger scale, where we might expect the effective temperature of the device to not be sufficiently low. To this end, we have applied nested quantum annealing correction (NQAC) to do unsupervised learning with a small bars and stripes dataset, and to do supervised learning with a coarse-grained MNIST dataset, which consists of black-And-white images of hand-written integers. For both datasets we demonstrate improved training and a concomitant effective temperature reduction at higher noise levels relative to the unencoded case. We also find better performance overall with longer anneal times and offer an interpretation of the results based on a comparison to simulated quantum annealing and spin vector Monte Carlo. A counterintuitive aspect of our results is that the output distribution generally becomes less Gibbs-like with increasing nesting level and increasing anneal times, which shows that improved training performance can be achieved without equilibration to the target Gi

关键词： Temperature

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Dispatchable Virtual Oscillator control for Decentralized Inverter-dominated Power Systems: Analysis and Experiments

arXiv

引用

arXiv 2018年

作者： Seo, Gab-Su Colombino, Marcello Subotic, Irina Johnson, Brian Groß, Dominic Dörfler, Florian Power Systems Engineering Center National Renewable Energy Laboratory GoldenCO80401 United States Automatic Control Laboratory ETH Zurich Zurich8092 Switzerland Department of Electrical and Computer Engineering University of Washington SeattleWA98195 United States

—This paper presents an analysis and experimental validation of dispatchable virtual oscillator control (dVOC) for inverter-dominated power systems. dVOC is a promising decentralized control strategy that requires only local measurements to induce grid-forming behavior with programmable droop characteristics. It is dispatchable–i.e., the inverters can vary their power generation via user-defined power set-points and guarantees strong stability. To verify its feasibility, a testbed comprising multiple dVOC-programmed inverters with transmission line impedances is designed. With an embedded synchronization strategy, the dVOC inverters are capable of dynamic synchronization, black start operation, and transient grid voltage regulation with dynamic load sharing, and real-time-programmable droop characteristics for backward compatibility. All these features are experimentally verified. Copyright © 2018, The Authors. All rights reserved.

关键词： Synchronization

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