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Compressibility-Near-Zero Acoustic Radiation

Physical Review Applied 2021年第2期15卷 024022-024022页

作者： Curtis Rasmussen Andrea Alù Department of Mechanical Engineering The University of Texas at Austin Austin Texas 78712 USA Department of Electrical and Computer Engineering The University of Texas at Austin Austin Texas 78712 USA Photonics Initiative CUNY Advanced Science Research Center New York New York 10031 USA Physics Program Graduate Center City University of New York New York New York 10026 USA

A hallmark of near-zero-index materials is the uniform phase profile that the waves experience as they propagate with staticlike properties in these media. This feature is exploited in electromagnetics for several applications, including for the realization of compact highly directive antennas illuminated by a single source. Here, we discuss the promise of near-zero metamaterials for acoustic radiation, based on the cutoff of a higher-order mode in a waveguide with small holes. We show that the near-zero nature of this phenomenon ensures unusual robustness to disorder, which is analyzed using a statistical description of the radiation patterns for randomly generated location of the holes. The radiation pattern can be made more directive by simply increasing the overall radiating aperture, without having to worry about the specific location of individual holes and their relative distance. The proposed zero-compressibility material offers a promising alternative to traditional acoustic directive sources due to its design simplicity, inherent robustness, and compact profile.

关键词： Acoustic metamaterials Acoustic wave phenomena Disordered systems Acoustic techniques Cavity resonators Green's function methods

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Simulation of arrow-shaped micromixer with obstacles in blood plasma mixing

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AIP Conference Proceedings 2024年第1期3080卷

作者： Ziyan Muhammad Aqsha Basari Mohammad Akita Indianto Ridho Irwansyah Muhammad Satrio Utomo Siti Fauziyah Rahman Biomedical Engineering Study Program Department of Electrical Engineering Faculty of Engineering Universitas Indonesia Kampus UI Depok West Java 16424 Indonesia Research Center for Biomedical Engineering Faculty of Engineering Universitas Indonesia Kampus UI Depok West Java 16424 Indonesia Energy Systems Engineering Graduate Program Faculty of Engineering Universitas Indonesia Kampus UI Depok West Java 16424 Indonesia Department of Mechanical Engineering Faculty of Engineering Universitas Indonesia Kampus UI Depok West Java 16424 Indonesia Research Center for Metallurgy National Research and Innovation Agency Komplek PUSPIPTEK Setu Tangerang Selatan Banten 15314 Indonesia

In recent years, several applications of micromixers have been reported to have a number of advantages, including the use of small amounts of plasma, short reaction times, and good reaction efficiency. The samples analyzed in this study were blood plasma and distilled water. The process is carried out by passive mixing which is based on a microchannel structure to enhance the diffusion of molecules for efficient mixing. The arrow shape was chosen as the micromixer design because it has a better blending performance than the T and Y shapes. The types of obstacles also used to improve the mixing process. The simulation was carried out on COMSOL Multiphysics software version 5.6. The results showed better mixing results for the micromixer design with triangle right facing obstacles with the highest Reynolds number was 9.4326. Then followed by ellips obstacles with a value of 9.4322, then without obstacles that is 9.4309, after that the triangle left facing with a value of 9.4006, and finally the lowest Reynolds number is a design with a diamond obstacles of 9.2514.

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Phase-induced frequency conversion and doppler effect with time-modulated metasurfaces

arXiv

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arXiv 2021年

作者： Ramaccia, Davide Sounas, Dimitrios L. Alù, Andrea Toscano, Alessandro Bilotti, Filiberto Department of Engineering ROMA TRE University Via Vito Volterra 62 Rome00146 Italy Department of Electrical and Computer Engineering Wayne State University DetroitMI48202 United States Photonics Initiative Advanced Science Research Center Physics Program Graduate Center Department of Electrical Engineering City College City University of New York New YorkNY10031 United States

Metasurfaces consisting of electrically thin and densely packed planar arrays of subwavelength elements enable an unprecedented control of the impinging electromagnetic fields. Spatially modulated metasurfaces can efficiently tailor the spatial distribution of these fields with great flexibility. Similarly, time modulated metasurfaces can be successfully used to manipulate the frequency content and time variations of the impinging field. In this paper, we present time-modulated reflective metasurfaces that cause a frequency shift to the impinging radiation, thus realizing an artificial Doppler effect in a non-moving electrically thin structure. Starting from the theoretical analysis, we analytically derive the required time modulation of the surface admittance to achieve this effect, and present a realistic time-varying structure, based on a properly designed and dynamically tuned high-impedance surface. It is analytically and numerically demonstrated that the field emerging from the metasurface is up-/down-converted in frequency according to the modulation profile of the metasurface. The proposed metasurface concept, enabling a frequency modulation of the electromagnetic field "on-the-fly", may find application in telecommunication, radar, and sensing scenarios. Copyright © 2021, The Authors. All rights reserved.

关键词： Doppler effect

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Young Women Exposed Actively to the Value of biomedical engineering

Young Women Exposed Actively to the Value of Biomedical Engi...

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Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Lara A. Thompson Nian Zhang Department of Mechanical Engineering Biomedical Engineering Program University of the District of Columbia Washington DC USA Department of Electrical & Computer Engineering University of the District of Columbia Washington DC USA

ISBN: (数字)9781728119908

ISBN: (纸本)9781728119915

To bridge the gap between the biological sciences (typically female-dominated) and engineering (typically male-dominated), biomedical engineering (BME) activities could potentially be used as a vehicle to alter female students' perception of engineering as a whole. Female's pursuit of STEM (Science, Technology, engineering and Math) degrees is typically confined to the biological sciences and females earn a high proportion of degrees in nursing, psychology and the social sciences, yet male presence persists in physical sciences and engineering. Female's participation in engineering remains much lower than men at all degree levels. Here, research questions included do female high school students: 1) perceive engineering as relevant? 2) have an interest & aptitude towards exploring engineering in college and as a career? 3) have anxiety in terms of engineering? 4) have engineering "role-confidence"? Participants, a randomly selected pool of 28 high school students (almost exclusively female from schools throughout the DC Metro area) took part in a week-long, all-day workshop where they were exposed to female engineering mentors, peers, and activities tied to BME & engineering. Pre and post surveys, adapted from standard STEM surveys, were administered to the pool of participants. Increases in confidence and interest in engineering and decreased anxiety were observed following female high school students' participation in hands-on activities in BME.

关键词： STEM Weaving Conferences Biology biomedical engineering Robots engineering profession

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biomedical data and AI

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Science China Life Sciences 2025年第5期68卷 1536-1540页

作者： Hao Xu Shibo Zhou Zefeng Zhu Vincenzo Vitelli Liangyi Chen Ziwei Dai Ning Yang Luhua Lai Shengyong Yang Sergey Ovchinnikov Zhuoran Qiao Sirui Liu Chen Song Jianfeng Pei Han Wen Jianfeng Feng Yaoyao Zhang Zhengwei Xie Yang-Yu Liu Zhiyuan Li Fulai Jin Hao Li Mohammad Lotfollahi Xuegong Zhang Ge Yang Shihua Zhang Ge Gao Pulin Li Qi Liu Jing-Dong Jackie Han Peking-Tsinghua Center for Life Sciences (CLS) Academy for Advanced Interdisciplinary StudiesPeking University Center for Quantitative Biology (CQB) Academy for Advanced Interdisciplinary StudiesPeking University Peking University-Tsinghua University-National Institute of Biological Sciences Joint Graduate Program Academy for Advanced Interdisciplinary StudiesPeking University Department of Physics University of Chicago School of Life Sciences Southern University of Science and Technology Peking University Chengdu Academy for Advanced Interdisciplinary Biotechnologies College of Chemistry and Molecular Engineering Peking University Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan University Department of Biology Massachusetts Institute of Technology Lambic Therapeutics Inc. Changping Laboratory Al for Science Institute Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence Fudan University Department of Obstetrics and Gynecology West China Second University HospitalSichuan University Peking University International Cancer Institute and Peking University-Yunnan Baiyao International Medical Institute and State Key Laboratory of Natural and Biomimetic Drugs Department of Molecular and Cellular PharmacologySchool of Pharmaceutical SciencesPeking University Health Science CenterPeking University Channing Division of Network Medicine Department of MedicineBrigham and Women's Hospital and Harvard Medical School Center for Artificial Intelligence and Modeling the Carl R.Woese Institute for Genomic BiologyUniversity of Illinois Urbana-Champaign Department of Genetics and Genome Sciences School of Medicine and Department of Computer and Data Sciences and Department of Population and Quantitative Health SciencesCase Western Reserve University Department of Biochemistry and Biophysics University of California Sanger Institute Department of Automation Tsinghua University State Key Laboratory of Multimodal Artificial Intelligence Systems I

The development of artificial intelligence(AI) and the mining of biomedical data complement each other. From the direct use of computer vision results to analyze medical images for disease screening, to now integrating biological knowledge into models and even accelerating the development of new AI based on biological discoveries, the boundaries of both are constantly expanding, and their connections are becoming closer.

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Shape Anisotropy-Governed High-Performance Nanomagnetosol for In Vivo Magnetic Particle Imaging of Lungs

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Small 2024年第5期20卷 e2305300页

作者： Nigam, Saumya Mohapatra, Jeotikanta Makela, Ashley V. Hayat, Hanaan Rodriguez, Jessi Mercedes Sun, Aixia Kenyon, Elizabeth Redman, Nathan A. Spence, Dana Jabin, George Gu, Bin Ashry, Mohamed Sempere, Lorenzo F. Mitra, Arijit Li, Jinxing Chen, Jiahui Wei, Guo-Wei Bolin, Steven Etchebarne, Brett Liu, J. Ping Contag, Christopher H. Wang, Ping Precision Health Program Michigan State University East LansingMI48824 United States Department of Radiology College of Human Medicine Michigan State University East LansingMI48824 United States Department of Physics The University of Texas at Arlington ArlingtonTX76019 United States Michigan State University East LansingMI48824 United States Department of Biomedical Engineering College of Engineering Michigan State University East LansingMI48824 United States Human Biology Program College of Natural Science Michigan State University East LansingMI48824 United States Department of Obstetrics Gynecology and Reproductive Sciences College of Human Medicine Michigan State University East LansingMI48824 United States Department of Materials Science and Engineering National Cheng Kung University Tainan City701 Taiwan Department of Mathematics College of Natural Science Michigan State U niversity East LansingMI48824 United States Department of Electrical and Computer Engineering College of Engineering Michigan State University East LansingMI48824 United States Department of Biochemistry and Molecular Biology College of Natural Science Michigan State University East LansingMI48824 United States Department of Pathobiology and Diagnostic Investigation College of Veterinary Medicine Michigan State University East LansingMI48824 United States Osteopathic Medical Specialties College of Osteopathic Medicine Michigan State University East LansingMI48824 United States Department of Microbiology and Molecular Genetics Michigan State University East LansingMI48824 United States

Caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), coronavirus disease 2019 (COVID-19) has shown extensive lung manifestations in vulnerable individuals, putting lung imaging and monitoring at the forefront of early detection and treatment. Magnetic particle imaging (MPI) is an imaging modality, which can bring excellent contrast, sensitivity, and signal-to-noise ratios to lung imaging for the development of new theranostic approaches for respiratory diseases. Advances in MPI tracers would offer additional improvements and increase the potential for clinical translation of MPI. Here, a high-performance nanotracer based on shape anisotropy of magnetic nanoparticles is developed and its use in MPI imaging of the lung is demonstrated. Shape anisotropy proves to be a critical parameter for increasing signal intensity and resolution and exceeding those properties of conventional spherical nanoparticles. The 0D nanoparticles exhibit a 2-fold increase, while the 1D nanorods have a > 5-fold increase in signal intensity when compared to VivoTrax. Newly designed 1D nanorods displayed high signal intensities and excellent resolution in lung images. A spatiotemporal lung imaging study in mice revealed that this tracer offers new opportunities for monitoring disease and guiding intervention. © 2023 The Authors. Small published by Wiley-VCH GmbH.

关键词： Nanorods

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MaxHiC: A robust background correction model to identify biologically relevant chromatin interactions in Hi-C and capture Hi-C experiments (vol 18, e1010241, 2022)

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PLOS COMPUTATIONAL BIOLOGY 2022年第9期18卷 e1010241页

作者： Alinejad-Rokny, Hamid Modegh, Rassa Ghavami Rabiee, Hamid R. Sarbandi, Ehsan Ramezani Rezaie, Narges Tam, Kin Tung Forrest, Alistair R. R. Harry Perkins Institute of Medical Research QEII Medical Centre and Centre for Medical Research The University of Western Australia Perth Australia Bio Medical Machine Learning Lab (BML) The Graduate School of Biomedical Engineering UNSW Sydney Sydney Australia Health Data Analytics Program AI-enabled Processes (AIP) Research Centre Macquarie University Sydney Australia Bioinformatics and Computational Biology Lab Department of Computer Engineering Sharif University of Technology Tehran Iran Center for Complex Biological Systems University of California Irvine Irvine California United States of America

Hi-C is a genome-wide chromosome conformation capture technology that detects interactions between pairs of genomic regions and exploits higher order chromatin structures. Conceptually Hi-C data counts interaction frequencies between every position in the genome and every other position. Biologically functional interactions are expected to occur more frequently than transient background and artefactual interactions. To identify biologically relevant interactions, several background models that take biases such as distance, GC content and mappability into account have been proposed. Here we introduce MaxHiC, a background correction tool that deals with these complex biases and robustly identifies statistically significant interactions in both Hi-C and capture Hi-C experiments. MaxHiC uses a negative binomial distribution model and a maximum likelihood technique to correct biases in both Hi-C and capture Hi-C libraries. We systematically benchmark MaxHiC against major Hi-C background correction tools including Hi-C significant interaction callers (SIC) and Hi-C loop callers using published Hi-C, capture Hi-C, and Micro-C datasets. Our results demonstrate that 1) Interacting regions identified by MaxHiC have significantly greater levels of overlap with known regulatory features (e.g. active chromatin histone marks, CTCF binding sites, DNase sensitivity) and also disease-associated genome-wide association SNPs than those identified by currently existing models, 2) the pairs of interacting regions are more likely to be linked by eQTL pairs and 3) more likely to link known regulatory features including known functional enhancer-promoter pairs validated by CRISPRi than any of the existing methods. We also demonstrate that interactions between different genomic region types have distinct distance distributions only revealed by MaxHiC. MaxHiC is publicly available as a python package for the analysis of Hi-C, capture Hi-C and Micro-C data.

关键词： Genomics Chromatin Genome-wide association studies Single nucleotide polymorphisms Histones Gene regulation Deoxyribonucleases Insulators

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Unitary Excitation Transfer between Coupled Cavities Using Temporal Switching

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Physical Review Letters 2021年第1期127卷 013902-013902页

作者： Yarden Mazor Michele Cotrufo Andrea Alù Department of Electrical and Computer Engineering The University of Texas at Austin Austin Texas 78712 USA School of Electrical Engineering Tel-Aviv University Ramat-Aviv Tel-Aviv 69978 Israel Photonics Initiative Advanced Science Research Center City University of New York New York New York 10031 USA Physics Program Graduate Center of the City University of New York New York New York 10016 USA

Tailored time variations can enable efficient control over signal flows, giving rise to exotic wave phenomena. In this work, we demonstrate how abrupt temporal switching of the coupling between two cavities can tailor the energy flow between them beyond the limitations of static scenarios, enabling unitary excitation transfer. The proposed scheme is robust with respect to a wide range of nonidealities, with implications for classical and quantum phenomena, from computing to nanophotonic systems.

关键词： Metamaterials Coupled oscillators

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Shoulder Flexion Pre-Movement Recognition Through Subject-Specific Brain Regions to Command an Upper Limb Exoskeleton

Shoulder Flexion Pre-Movement Recognition Through Subject-Sp...

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Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Yunier Prieur-Coloma Denis Delisle-Rodríguez Leondry Mayeta-Revilla Dharmendra Gurve Ramón A. Reinoso-Leblanch Alberto López-Delis Teodiano Bastos Sri Krishnan Adson F. da Rocha Center of Medical Biophysics University of Oriente Cuba Postgraduate Program in Electrical Engineering Federal University of Espirito Santo Brazil Department of Biomedical Engineering University of Oriente Cuba Department of Electrical Computer and Biomedical Engineering Ryerson University Toronto Canada Department of Electrical Engineering University of Brasilia Brasilia Brasil

ISBN: (数字)9781728119908

ISBN: (纸本)9781728119915

This work presents two brain-computer interfaces (BCIs) for shoulder pre-movement recognition using: 1) manual strategy for Electroencephalography (EEG) channels selection, and 2) subject-specific channels selection by applying non-negative factorization matrix (NMF). Besides, the proposed BCIs compute spatial features extracted from filtered EEG signals through Riemannian covariance matrices and a linear discriminant analysis (LDA) to discriminate both shoulder pre-movement and rest states. We studied on twenty-one healthy subjects different frequency ranges looking the best frequency band for shoulder pre-movement recognition. As a result, our BCI located automatically EEG channels on the contralateral moved limb, and enhancing the pre-movement recognition (ACC = 71.39 ± 12.68%, κ = 0.43 ± 0.25%). The ability of the proposed BCIs to select specific EEG locations more cortically related to the moved limb could benefit the neuro-rehabilitation process.

关键词： Electroencephalography Manuals Covariance matrices Shoulder Frequency measurement Exoskeletons Brain-computer interfaces

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Enhanced Superconducting Qubit Performance Through Ammonium Fluoride Etch

arXiv

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arXiv 2024年

作者： Kopas, Cameron J. Goronzy, Dominic P. Pham, Thang Torres Castanedo, Carlos G. Cheng, Matthew Cochrane, Rory Nast, Patrick Lachman, Ella Zhelev, Nikolay Z. Vallières, André Murthy, Akshay A. Oh, Jin-Su Zhou, Lin Kramer, Matthew J. Cansizoglu, Hilal Bedzyk, Michael J. Dravid, Vinayak P. Romanenko, Alexander Grassellino, Anna Mutus, Josh Y. Hersam, Mark C. Yadavalli, Kameshwar Rigetti Computing BerkeleyCA United States Department of Materials Science and Engineering Northwestern University EvanstonIL United States Center for Applied Physics and Superconducting Technologies Northwestern University EvanstonIL United States Department of Physics and Astronomy Northwestern University EvanstonIL United States Department of Physics University of Oregon EugeneOR United States Graduate Program in Applied Physics Northwestern University EvanstonIL60208 United States Fermi National Accelerator Laboratory BataviaIL United States Ames Laboratory U.S. Department of Energy AmesIA United States Northwestern University EvanstonIL United States Department of Chemistry Northwestern University EvanstonIL United States Department of Electrical and Computer Engineering Northwestern University EvanstonIL United States

The performance of superconducting qubits is often limited by dissipation and two-level systems (TLS) losses. The dominant sources of these losses are believed to originate from amorphous materials and defects at interfaces and surfaces, likely as a result of fabrication processes or ambient exposure. Here, we explore a novel wet chemical surface treatment at the Josephson junction-substrate and the substrate-air interfaces by replacing a buffered oxide etch (BOE) cleaning process with one that uses hydrofluoric acid followed by aqueous ammonium fluoride. We show that the ammonium fluoride etch process results in a statistically significant improvement in median T1 by ∼ 22% (p = 0.002), and a reduction in the number of strongly-coupled TLS in the tunable frequency range. Microwave resonator measurements on samples treated with the ammonium fluoride etch prior to niobium deposition also show ∼ 33% lower TLS-induced loss tangent compared to the BOE treated samples. As the chemical treatment primarily modifies the Josephson junction-substrate interface and substrate-air interface, we perform targeted chemical and structural characterizations to examine materials’ differences at these interfaces and identify multiple microscopic changes that could contribute to decreased TLS. © 2024, CC BY-NC-ND.

关键词： Fluorine compounds

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