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A deterministic Susceptible–Infected–Recovered model for studying the impact of media on epidemic dynamics

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Healthcare Analytics 2023年 3卷 100189-100189页

作者： Fome, Anna D. Rwezaura, Herieth Diagne, Mamadou L. Collinson, Shannon Tchuenche, Jean M. Department of Economics Mathematics and Statistics Jordan University College Morogoro Tanzania Mathematics Department University of Dar es Salaam P.O. Box 35062 Dar es Salaam Tanzania Département de Mathématiques UFR des Sciences et Technologies Université de Thiès BP 967 Thiès Senegal Centre for Disease Modelling York University Canada School of Computational and Communication Sciences and Engineering Nelson Mandela African Institution of Science and Technology P.O. Box 447 Arusha Tanzania School of Computer Science and Applied Mathematics University of the Witwatersrand Private Bag 3 Wits 2050 Johannesburg South Africa

It is important to understand how the provision of information influences individuals’ behavior and its impact on disease transmission dynamics. We formulate a simple deterministic Susceptible–Infected–Recovered (SIR) model with vital dynamics and incorporate, one at a time, four media functions used in previous studies to mimic media reporting of a disease outbreak to investigate their impact on the dynamics of an epidemic. The most sensitive model parameter for the epidemic outcome at initial disease transmission and disease prevalence are obtained through normalized forward-sensitivity analyses. Media reporting does not impact initial disease transmission but affects the effective reproduction number as the media coverage begins. Numerical results show that the epidemic will affect a large proportion of the population with no media functions. Still, the epidemic time line may be short. In contrast, the key epidemiological quantities (such as age at infection, peak magnitude, peak time, end of the epidemic, and final epidemic size) vary depending on the media function used. The choice of the media function in a pandemic is critical. The media reporting on the spread of disease during pandemics should be done with care since it could counter-intuitively lead to under or overestimating the disease outbreak. © 2023 The Author(s)

关键词： Deterministic model Disease outbreak Epidemic dynamics Media coverage Sensitivity analysis Susceptible–infected–recovered

Integrability of Goldilocks quantum cellular automata

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arXiv 2024年

作者： Hillberry, Logan E. Piroli, Lorenzo Vernier, Eric Halpern, Nicole Yunger Prosen, Tomaž Carr, Lincoln D. Department of Physics The University of Texas at Austin AustinTX78712 United States Dipartimento di Fisica e Astronomia Università di Bologna INFN Sezione di Bologna via Irnerio 46 BolognaI-40126 Italy Laboratoire de Probabilités Statistique et Modélisation CNRS Université Paris Cité Sorbonne Université Paris France Joint Center for Quantum Information and Computer Science NIST University of Maryland College ParkMD20742 United States Institute for Physical Science and Technology University of Maryland College ParkMD20742 United States Faculty of Mathematics and Physics University of Ljubljana Jadranska 19 LjubljanaSI-1000 Slovenia Institute of Mathematics Physics and Mechanics Jadranska 19 LjubljanaSI-1000 Slovenia Quantum Engineering Program Colorado School of Mines GoldenCO80401 United States Department of Physics Colorado School of Mines GoldenCO80401 United States Department of Applied Mathematics and Statistics Colorado School of Mines GoldenCO80401 United States

Goldilocks quantum cellular automata (QCA) have been simulated on quantum hardware and produce emergent small-world correlation networks. In Goldilocks QCA, a single-qubit unitary is applied to each qubit in a one-dimensional chain subject to a balance constraint: a qubit is updated if its neighbors are in opposite basis states. Here, we prove that a subclass of Goldilocks QCA—including the one implemented experimentally—map onto free fermions and therefore can be classically simulated efficiently. We support this claim with two independent proofs, one involving a Jordan–Wigner transformation and one mapping the integrable six-vertex model to QCA. We compute local conserved quantities of these QCA and predict experimentally measurable expectation values. These calculations can be applied to test large digital quantum computers against known solutions. In contrast, typical Goldilocks QCA have equilibration properties and quasienergy-level statistics that suggest nonintegrability. Still, the latter QCA conserve one quantity useful for error mitigation. Our work provides a parametric quantum circuit with tunable integrability properties with which to test quantum hardware. © 2024, CC BY.

关键词： Qubits

COMPARING PERFORMANCE OF CROP SPECIES MIXTURES AND PURE STANDS

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Frontiers of Agricultural Science and engineering 2021年第3期8卷 481-489页

作者： Wopke VAN DER WERF Lizhen ZHANG Chunjie LI Ping CHEN Chen FENG Zhan XU Chaochun ZHANG Chunfeng GU Lammert BASTIAANS David MAKOWSKI TjeerdJan STOMPH Wageningen University Centre for Crop Systems Analysis6700 AK Wageningenthe Netherlands College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China College of Resources and Environmental Sciences National Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China College of Agronomy/Sichuan Engineering Research Center for Crop Strip Intercropping System/Key Laboratory of Crop Ecophysiology and Farming System in Southwest Ministry of Agriculture and Rural Affairs of ChinaChengdu 611130China Tillage and Cultivation Research Institute Liaoning Academy of Agricultural SciencesShenyang 110161China INRAe AgroParisTechUniversitéParis-SaclayUnit Applied Mathematics and Computer Science(UMR MIA 518)16 rue Claude Bernard F-75231 ParisFrance

Intercropping is the planned cultivation of species mixtures on agricultural *** has many attributes that make it attractive for developing a more sustainable agriculture,such as high yield,high resource use efficiency,lower input requirements,natural suppression of pests,pathogens and weeds,and building a soil with more organic carbon and *** is needed which species combinations perform best under different circumstances and which management is suitable to bring out the best from intercropping in a given production *** literature is replete with case studies on intercropping from across the globe,but evidence synthesis is needed to make this information ***-analysis requires a careful choice of metric that is appropriate for answering the question at hand,and which lends itself for a robust *** paper reviews some metrics that may be used in the quantitative synthesis of literature data on intercropping.

关键词： intercropping species mixtures metaanalysis metrics indicators

Symbolic genetic algorithm for discovering open-form partial differential equations (SGA-PDE)

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Physical Review Research 2022年第2期4卷 023174-023174页

作者： Yuntian Chen Yingtao Luo Qiang Liu Hao Xu Dongxiao Zhang Eastern Institute for Advanced Study Yongriver Institute of Technology Ningbo Zhejiang 315201 People's Republic of China Department of Computer Science University of Washington Seattle Washington 98195 USA RealAI Beijing 100085 People's Republic of China Beijing Innovation Center for Engineering Science and Advanced Technology (BIC-ESAT) Energy and Resources Engineering (ERE) and State Key Laboratory for Turbulence and Complex Systems (SKLTCS) College of Engineering Peking University Beijing 100871 People's Republic of China National Center for Applied Mathematics Shenzhen (NCAMS) Southern University of Science and Technology Shenzhen Guangdong 518055 People's Republic of China Department of Mathematics and Theories Peng Cheng Laboratory Shenzhen Guangdong 518000 People's Republic of China

Partial differential equations (PDEs) are concise and understandable representations of domain knowledge, which are essential for deepening our understanding of physical processes and predicting future responses. However, the PDEs of many real-world problems are uncertain, which calls for PDE discovery. We propose the symbolic genetic algorithm to discover open-form PDEs (SGA-PDE) directly from data without prior knowledge about the equation structure. SGA-PDE focuses on the representation and optimization of PDEs. Firstly, SGA-PDE uses symbolic mathematics to realize the flexible representation of any given PDE, transforms a PDE into a forest, and converts each function term into a binary tree. Secondly, SGA-PDE adopts a specially designed genetic algorithm to efficiently optimize the binary trees by iteratively updating the tree topology and node attributes. The SGA-PDE is gradient free, which is a desirable characteristic in PDE discovery since it is difficult to obtain the gradient between the PDE loss and the PDE structure. In the experiment, SGA-PDE not only successfully discovered the nonlinear Burgers’ equation, the Korteweg–de Vries equation, and the Chafee-Infante equation but also handled PDEs with fractional structure and compound functions that cannot be solved by conventional PDE discovery methods.

关键词： Classical statistical mechanics Complex fluids Neuronal dynamics Shock waves Turbulence

Distributed entanglement generation from asynchronously excited qubits

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arXiv 2020年

作者： Huan, Tian-Tian Zhou, Rigui Ian, Hou Institute of Applied Physics and Materials Engineering University of Macau China College of Mathematics and Computer Science Chifeng University Chifeng024000 China College of Information Engineering Shanghai Maritime University Shanghai201306 China

The generation of GHZ states calls for simultaneous excitation of multiple qubits. The peculiarity of such states is reflected in their nonzero distributed entanglement which is not contained in other entangled states. We study the optimal way to excite three superconducting qubits through a common cavity resonator in a circuit such that the generation of distributed entanglement among them could be obtained at the highest degree in a time-controllable way. A non-negative measure quantifying this entanglement is derived as a time function of the quadripartite system evolution. We find that this measure does not stay static but obtains the same maximum periodically. When the qubit-resonator couplings are allowed to vary, its peak value is enhanced monotonically by increasing the greatest coupling strength to one of the qubits. The period of its peak to peak revival maximizes when the couplings become inhomogeneous, thus qubit excitation becoming asynchronous, at a relative ratio of 0.35. The study demonstrates the role of asynchronous excitations for time-controlling multi-qubit systems, in particular in extending entanglement time. Copyright © 2020, The Authors. All rights reserved.

关键词： Quantum entanglement

OPINION MANIPULATION ON FARSI TWITTER

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arXiv 2022年

作者： Farzam, Amirhossein Moradi, Parham Mohammadi, Saeedeh Padar, Zahra Siegel, Alexandra A. Department of Political Science Duke University DurhamNC27708 United States Department of Engineering Sciences and Applied Mathematics Northwestern University EvanstonIL60208 United States Max Planck Institute for Mathematics in the Sciences Leipzig04103 Germany Center for Complex Networks and Social Data Science Tehran Iran Department of Physics Shahid Beheshti University Tehran Iran School of Mathematics and Statistics University College Dublin BelfieldDublin 4 Ireland Department of Computer Science University of Freiburg Freiburg Germany Department of Political Science University of Colorado BoulderCO80309 United States

For Iranians and the Iranian diaspora, the Farsi Twittersphere provides an important alternative to state media and an outlet for political discourse. But this understudied online space has become an opinion manipulation battleground, with diverse actors using inauthentic accounts to advance their goals and shape online narratives. Examining trending discussions crossing social cleavages in Iran, we explore how the dynamics of opinion manipulation differ across diverse issue areas. Our analysis suggests that opinion manipulation by inauthentic accounts is more prevalent in divisive political discussions than non-divisive or apolitical discussions. We show how Twitter's network structures help to reinforce the content propagated by clusters of inauthentic accounts in divisive political discussions. Analyzing both the content and structure of online discussions in the Iranian Twittersphere, this work contributes to a growing body of literature exploring the dynamics of online opinion manipulation, while improving our understanding of how information is controlled in the digital age. © 2022, CC BY.

关键词： Social networking (online)

Minimum-complexity graph simplification under Fréchet-like distances

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arXiv 2021年

作者： Filtser, Omrit Mirzanezhad, Majid Wenk, Carola Department of Applied Mathematics and Statistics State University of New York at Stony Brook NY United States Transportation Research Institute College of Engineering University of Michigan Ann ArborMI United States Department of Computer Science Tulane University New OrleansLA United States

Simplifying graphs is a very applicable problem in numerous domains especially in computational geometry. Given a geometric graph and a threshold, the minimum-complexity graph simplification asks for computing an alternative graph of minimum complexity so that the distance between the two graphs remains at most the threshold. In this paper we propose several NP-hardness and algorithmic results depending on the type of input and simplified graphs, the vertex placement of the simplified graph, and the distance measures between them (graph and traversal distances [1, 2]). In general, we show that for arbitrary input and output graphs, the problem is NP-hard under some specific vertex-placement of the simplified graph. When the input and output are trees, and the graph distance is applied from the simplified tree to the input tree, we give an O(kn5) time algorithm, where k is the number of the leaves of the two trees that are identical and n is the number of vertices of the input. © 2021, CC BY.

关键词： Graphic methods

A Non-negative Matrix Factorization Based Method for Identifying Essential Proteins

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Research Square

Research Square 2021年

作者： Zhang, Zhihong Hu, Sai Yan, Wei Zhao, Bihai Wang, Lei School of Information Technology and Management Hunan University of Finance and Economics Changsha410205 China College of Computer Engineering and Applied Mathematics Changsha University Hunan Changsha410022 China Hunan Provincial Key Laboratory of Nutrition and Quality Control of AquaticAnimals Department of Biological and Environmental Engineering Changsha University Hunan Changsha410022 China

Background Identification of essential proteins is very important for understanding the basic requirements to sustain a living organism. In recent years, various different computational methods have been proposed to identify essential proteins based on protein-protein interaction (PPI) networks. However, there has been reliable evidence that a huge amount of false negatives and false positives exist in PPI data. Therefore, it is necessary to reduce the influence of false data on accuracy of essential proteins prediction by integrating multi-source biological information with PPI networks. Results In this paper, we proposed a non-negative matrix factorization and multiple biological information based model (NDM) for identifying essential proteins. The first stage in this progress was to construct a weighted PPI network by combing the information of protein domain, protein complex and the topology characteristic of the original PPI network. Then, the non-negative matrix factorization technique was used to reconstruct an optimized PPI network with whole enough weight of edges. In the final stage, the ranking score of each protein was computed by the PageRank algorithm in which the initial scores were calculated with homologous and subcellular localization information. In order to verify the effectiveness of the NDM method, we compared the NDM with other state-of-the-art essential proteins prediction methods. The comparison of the results obtained from different methods indicated that our NDM model has better performance in predicting essential proteins. Conclusion Employing the non-negative matrix factorization and integrating multi-source biological data can effectively improve quality of the PPI network, which resulted in the led to optimization of the performance essential proteins identification. This will also provide a new perspective for other prediction based on protein-protein interaction networks. © 2021, CC BY.

关键词： Non-negative matrix factorization

Multiregion Multiscale Image Segmentation with Anisotropic Diffusion 25th

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Multiregion Multiscale Image Segmentation with Anisotropic D...

25th International Conference on Pattern Recognition Workshops, ICPR 2020

作者： Prasath, V. B. Surya Thanh, Dang Ngoc Hoang Hai, Nguyen Hoang Dvoenko, Sergey Department of Electrical Engineering and Computer Science University of Cincinnati CincinnatiOH45221 United States Division of Biomedical Informatics Cincinnati Children’s Hospital Medical Center CincinnatiOH45229 United States Department of Biomedical Informatics College of Medicine University of Cincinnati CincinnatiOH45267 United States Department of Pediatrics University of Cincinnati College of Medicine CincinnatiOH45257 United States Department of Information Technology School of Business Information Technology University of Economics Ho Chi Minh City Ho Chi Minh City Viet Nam Department of Computer Science Vietnam-Korea University of Information and Communication Technology – The University of Danang Danang Viet Nam Department of Information Security Institute of Applied Mathematics and Computer Science Tula State University Tula city Russia

ISBN: (纸本)9783030688202

We present a multiregion image segmentation approach which utilizes multiscale anisotropic diffusion based scale spaces. By combining powerful edge preserving anisotropic diffusion smoothing with isolevel set linking and merging, we obtain coherent segments which are tracked across multiple scales. A hierarchical tree representation of the given input image with progressively simplified regions is used with intra-scale splitting and inter-scale merging for obtaining multiregion segmentations. Experimental results on natural and medical images indicate that multiregion, multiscale image segmentation (MMIS) approach obtains coherent segmentation results. © 2021, Springer Nature Switzerland AG.

关键词： Diffusion