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Multiline orthogonal scanning temporal focusing (mosTF) microscopy for scattering reduction in high-speed in vivo brain imaging

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arXiv 2019年

作者： Xue, Yi Boivin, Josiah R. Wadduwage, Dushan N. Park, Jong Kang Nedivi, Elly So, Peter T.C. Dept. of Mechanical Engineering Massachusetts Institute of Technology 77 Massachusetts Ave. CambridgeMA02139 Singapore Laser Biomedical Research Center Massachusetts Institute of Technology 77 Massachusetts Ave. CambridgeMA02139 Singapore Picower Institute Massachusetts Institute of Technology 77 Massachusetts Ave. CambridgeMA02139 United States Dept. of Biological Engineering Massachusetts Institute of Technology 77 Massachusetts Ave. CambridgeMA02139 Singapore Dept. of Biology Massachusetts Institute of Technology 77 Massachusetts Ave. CambridgeMA02139 Singapore Dept. of Brain and Cognitive Sciences Massachusetts Institute of Technology 77 Massachusetts Ave. CambridgeMA02139 United States Center for Advanced Imaging Faculty of Arts and Sciences Harvard University CambridgeMA02138 Dept. of Electrical Engineering and Computer Sciences University of California BerkeleyCA94720 United States

Temporal focusing two-photon microscopy enables high resolution imaging of fine structures in vivo over a large volume. A limitation of temporal focusing is that signal-to-background ratio and resolution degrade rapidly with increasing imaging depth. This degradation originates from the scattered emission photons are widely distributed resulting in a strong background. We have developed Multiline Orthogonal Scanning Temporal Focusing (mosTF) microscopy that overcomes this problem. mosTF captures a sequence of images at each scan location of the excitation line, followed by a reconstruction algorithm reassigns scattered photons back to the correct scan position. We demonstrate mosTF by acquiring mice neuronal images in vivo. Our results show remarkably improvements with mosTF for in vivo brain imaging while maintaining its speed advantage. Copyright © 2019, The Authors. All rights reserved.

关键词： Photons

Probing the universality of topological defect formation in a quantum annealer: Kibble-Zurek mechanism and beyond

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arXiv 2020年

作者： Bando, Yuki Susa, Yuki Oshiyama, Hiroki Shibata, Naokazu Ohzeki, Masayuki Gómez-Ruiz, Fernando Javier Lidar, Daniel A. Suzuki, Sei del Campo, Adolfo Nishimori, Hidetoshi Institute of Innovative Research Tokyo Institute of Technology Nagatsuta-cho Midori-ku Yokohama226-8503 Japan Institute of Innovative Research Tokyo Institute of Technology Oh-okayama Meguro-ku Tokyo152-8550 Japan Department of Physics Tohoku University Sendai980-8578 Japan Graduate School of Information Sciences Tohoku University Sendai980-8579 Japan Sigma-i Co. Ltd. Konan Minato-ku Tokyo108-0075 Japan Donostia International Physics Center San SebastiánE-20018 Spain Departments of Electrical and Computer Engineering Chemistry and Physics University of Southern California Los AngelesCA90089 United States Center for Quantum Information Science & Technology University of Southern California Los AngelesCA90089 United States Department of Liberal Arts Saitama Medical University Moroyama Saitama350-0495 Japan IKERBASQUE Basque Foundation for Science BilbaoE-48013 Spain Department of Physics University of Massachusetts Boston 100 Morrissey Boulevard BostonMA02125 United States Wako Saitama351-0198 Japan

The number of topological defects created in a system driven through a quantum phase transition exhibits a power-law scaling with the driving time. This universal scaling law is the key prediction of the Kibble-Zurek mechanism (KZM), and testing it using a hardware-based quantum simulator is a coveted goal of quantum information science. Here we provide such a test using quantum annealing. Specifically, we report on extensive experimental tests of topological defect formation via the one-dimensional transverse-field Ising model on two different D-Wave quantum annealing devices. We find that the quantum simulator results can indeed be explained by the KZM for open-system quantum dynamics with certain quantitative deviations from the theory likely caused by factors such as random control errors and transient effects. We also probe physics beyond the KZM by identifying signatures of universality in the distribution and cumulants of the number of kinks, and again find agreement with the quantum simulator results. This implies that the predictions of generalized KZM theory for an isolated system, applies beyond its original scope to an open system. This amounts to the first experimental observation of previously unknown behavior of a quantum system via quantum simulation. To check whether an alternative, classical interpretation of these results is possible, we used the spin-vector Monte Carlo model, a candidate classical description of the D-Wave device. We find that the degree of agreement with the experimental data from the D-Wave devices is better for the KZM, a quantum theory, than for the classical spin-vector Monte Carlo model, thus favoring a quantum description of the device. Our work provides an experimental test of quantum critical dynamics in an open quantum system, and paves the way to new directions in quantum simulation experiments. Copyright © 2020, The Authors. All rights reserved.

关键词： Quantum optics

Unifying modular and core-periphery structure in functional brain networks over development

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arXiv 2019年

作者： Gu, Shi Xia, Cedric Huchuan Ciric, Rastko Moore, Tyler M. Gur, Ruben C. Gur, Raquel E. Satterthwaite, Theodore D. Bassett, Danielle S. School of Computer Science and Engineering University of Electronic Science and Technology of China Chengdu China Department of Psychiatry University of Pennsylvania PhiladelphiaPA19104 United States Department of Bioengineering School of Engineering and Applied Science University of Pennsylvania 210 S. 33rd Street 240 Skirkanich Hall PhiladelphiaPA19104-6321 Department of Physics and Astronomy College of Arts and Sciences University of Pennsylvania PhiladelphiaPA19104 United States Department of Electrical and Systems Engineering University of Pennsylvania PhiladelphiaPA19104 United States Department of Neurology Perelman School of Medicine University of Pennsylvania PhiladelphiaPA19104 United States

At rest, human brain functional networks display striking modular architecture in which coherent clusters of brain regions are activated. The modular account of brain function is pervasive, reliable, and reproducible. Yet, a complementary perspective posits a core-periphery or rich-club account of brain function, where hubs are densely interconnected with one another, allowing for integrative processing. Unifying these two perspectives has remained difficult due to the fact that the methodological tools to identify modules are entirely distinct from the methodological tools to identify core-periphery structure. Here we leverage a recently-developed model-based approach-the weighted stochastic block model-that simultaneously uncovers modular and core-periphery structure, and we apply it to fMRI data acquired at rest in 872 youth of the Philadelphia Neurodevelopmental Cohort. We demonstrate that functional brain networks display rich meso-scale organization beyond that sought by modularity maximization techniques. Moreover, we show that this meso-scale organization changes appreciably over the course of neurodevelopment, and that individual differences in this organization predict individual differences in cognition more accurately than module organization alone. Broadly, our study provides a unified assessment of modular and core-periphery structure in functional brain networks, providing novel insights into their development and implications for behavior. Copyright © 2019, The Authors. All rights reserved.

关键词： Brain

Compensation of perceived hardness of a virtual object with cutaneous feedback 7

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Compensation of perceived hardness of a virtual object with ...

7th IEEE World Haptics Conference, WHC 2017

作者： Park, Jaeyoung Kim, Jaeha Oh, Yonghwan Tan, Hong Z. Robotics and Media Institute Korean Institute of Science and Technology Seoul Korea Republic of Haptic Interface Research Laboratory School of Electrical and Computer Engineering Purdue University West LafayetteIN47907 United States

ISBN: (纸本)9781509014255

Wearable glove type haptic interfaces are often required to be light weight, which constrains the actuator to exert low torques. This causes a virtual object to feel compliant, reducing the range of presented surface properties. To overcome the limitation, we propose to compensate the hardness of a virtual object with cutaneous feedback. A cutaneous haptic interface is designed to present the hardness to a user's fingertip along with a force-feedback interface and the corresponding rendering strategy is proposed. Two experiments were conducted to evaluate the proposed approach for one-finger touch and two-finger grip for stiffness values under 0.3 N/mm. Experimental results indicate that the addition of cutaneous feedback led the virtual surface to feel significantly harder than the nominal stiffness felt by force-feedback alone. In addition, the perceived hardness was significantly affected by the rate of hardness rendered with cutaneous interface when the nominal stiffness was increased. © 2017 IEEE.

关键词： Haptic interfaces

Experiments in Routing Vehicles for Municipal Services

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Experiments in Routing Vehicles for Municipal Services

International Conference on High Performance Computing and Simulation

作者： Imran Mahmood Sahar Idwan Junaid Ahmed Zubairi Izzeddin Matar Center for Research in Modeling & Simulation School of Electrical Engineering and Computer Science National University of Sciences and Technology CS and Engineering Department School of Engineering American U of Ras Al Khaimah Ras al Khaimah UAE and Comp Sci & Apps Dept Hashemite University Computer and Information Sciences Department College of Liberal Arts and Sciences State University of New York at Fredonia Faculty of Information Technology Software Engineering Department University of Petra

ISBN: (纸本)9781538678800

In this paper, route planning of waste collection trucks using R&R (Ruin and Recreate) approach is explored. We assume the trucks are guided by the central depot in selecting the optimal route for waste collection. Heuristic algorithms are simulated to find the optimal routes for the waste management fleet. Through the use of smart dumpsters that can communicate the current level of waste using sensors and communication modules, we aim to reduce the number of trucks used, the total time taken and total distance traveled by the fleet in a day. Our work is based on variations of CVRPTW (Capacitated Vehicle Routing Problem with Time Window Constraint). The central management system selects the dumpsters, based on their waste levels, in descending order, and dispatches appropriate number of trucks, with path assignments using Ruin and Recreate (R&R) approach of the VRPTW strategy. The municipal authority saves transit time, fuel cost and service time by using our approach, through a simulation of smart waste collection.

关键词： Smart Dumpster Capacitated Vehicle Routing Problem with Time Window Constraint Ruin & Recreate Search heuristic Waste management Simulation

Adaptive Position Tracking Compensation for High-Speed Trains with Actuator Failures

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IFAC-PapersOnLine 2017年第1期50卷 14266-14271页

作者： Mao, Zehui Tao, Gang Jiang, Bin Yan, Xing-Gang Zhong, Maiying College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing210016 China Department of Electrical and Computer Engineering University of Virginia CharlottesvilleVA22904 United States School of Engineering and Digital Arts University of Kent Canterbury KentCT2 7NT United Kingdom Shandong University of Science and Technology Qingdao266590 China

In this paper, an adaptive failure compensation is proposed for high-speed trains with traction system actuator failures to achieve the position tracking. To deal with the time-varying parameters of the train motion dynamics, the piecewise constant model is introduced to describe the train dynamics with variable parameters. For the system with actuator failures, the adaptive controller with the adaptive laws is designed to achieve the position tracking, in the presence of the system piecewise constant parameters and actuator failure parameters which are unknown. Simulation results on a high-speed train model are presented to illustrate the performance of the developed adaptive actuator failure compensation control scheme. © 2017

关键词： Adaptive control systems Actuators Railroad cars Railroad transportation Railroads Tracking (position) Actuator failures Adaptive Control Adaptive controllers Failure compensation High speed train (HST) Piece wise constants Time varying parameter Tracking compensation

Distributed compressive sensing for correlated information sources 7th

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Distributed compressive sensing for correlated information s...

7th International Conference on Big Data Technologies and Applications, BDTA 2016

作者： Park, Jeonghun Hwang, Seunggye Yang, Janghoon Bae, Kitae Ko, Hoon Kim, Dong Ku Department of Electrical and Computer Engineeing University of Texas at Austin AustinTX United States LG Electronics Anyang Korea Republic of Department of New Media Contents Seoul Media Institute of Technology Seoul Korea Republic of College of Information and Communication Engineering Sungkyunkwan University Suwon Korea Republic of School of Electrical and Electronics Engineering Yonsei University Seoul Korea Republic of

ISBN: (纸本)9783319589664

The abstract should summarize the contents of the paper and should Distributed Compressive Sensing (DCS) improves the signal recovery performance of multi signal ensembles by exploiting both intra- and inter-signal correlation and sparsity structure. In this paper, we propose a novel algorithm, which improves detection performance even without a priori-knowledge on the correlation structure for arbitrarily correlated sparse signal. Numerical results verify that the propose algorithm reduces the required number of measurements for correlated sparse signal detection compared to the existing DCS algorithm. © ICST Institute for computer Sciences, Social Informatics and Telecommunications engineering 2017.

关键词： Compressed sensing

Room-temperature lasing action in GaN quantum wells in the infrared 1.5 µm region

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arXiv 2018年

作者： Ho, V.X. Al tahtamouni, T.M. Jiang, H.X. Lin, J.Y. Zavada, J.M. Vinh, N.Q. Department of Physics Center for Soft Matter and Biological Physics Virginia Tech BlacksburgVA24061 United States Materials Science & Technology Program College of Arts & Sciences Qatar University Doha2713 Qatar Department of Electrical and Computer Engineering Texas Tech University LubbockTX79409 United States Department of Electrical and Computer Engineering New York University BrooklynNY11201 United States

Large-scale optoelectronics integration is strongly limited by the lack of efficient light sources, which could be integrated with the silicon complementary metal-oxide-semiconductor (CMOS) technology. Persistent efforts continue to achieve efficient light emission from silicon in the extending the silicon technology into fully integrated optoelectronic circuits. Here, we report the realization of room-temperature stimulated emission in the technologically crucial 1.5 µm wavelength range from Er-doped GaN multiple-quantum wells on silicon and sapphire. Employing the well-acknowledged variable stripe technique, we have demonstrated an optical gain up to 170 cm-1 in the multiple-quantum well structures. The observation of the stimulated emission is accompanied by the characteristic threshold behavior of emission intensity as a function of pump fluence, spectral linewidth narrowing and excitation length. The demonstration of room-temperature lasing at the minimum loss window of optical fibers and in the eye-safe wavelength region of 1.5 µm are highly sought-after for use in many applications including defense, industrial processing, communication, medicine, spectroscopy and imaging. As the synthesis of Er-doped GaN epitaxial layers on silicon and sapphire has been successfully demonstrated, the results laid the foundation for achieving hybrid GaN-Si lasers providing a new pathway towards full photonic integration for silicon optoelectronics. Driven by the strong need for cheap and integrable Si-based optoelectronic devices for a wide range of applications, continuing endeavors have been made to develop structures for light emission, modulation, and detection in this material system. Recent breakthroughs including the demonstration of a high-speed optical modulator in Si,1-2 photodetectors3, and waveguides4 have brought the concept of transition from electrical to optical interconnects closer to realization. However, the base for silicon photonics, namely, a group IV la

关键词： Semiconductor quantum wells

Predictable and precise template-free CRISPR editing of pathogenic variants (vol 563, pg 646, 2018)

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NATURE 2019年第7746期567卷 E1-E2页

作者： Shen, Max W. Arbab, Mandana Hsu, Jonathan Y. Worstell, Daniel Culbertson, Sannie J. Krabbe, Olga Cassa, Christopher A. Liu, David R. Gifford, David K. Sherwood, Richard I. Computational and Systems Biology Program Massachusetts Institute of Technology Cambridge USA Computer Science and Artificial Intelligence Laboratory Massachusetts Institute of Technology Cambridge USA Merkin Institute of Transformative Technologies in Healthcare Broad Institute of Harvard and MIT Cambridge USA Department of Chemistry and Chemical Biology Harvard University Cambridge USA Howard Hughes Medical Institute Harvard University Cambridge USA Department of Biological Engineering Massachusetts Institute of Technology Cambridge USA Molecular Pathology Unit Center for Cancer Research and Center for Computational and Integrative Biology Massachusetts General Hospital Charlestown USA Division of Genetics Department of Medicine Brigham and Women’s Hospital and Harvard Medical School Boston USA Hubrecht Institute for Developmental Biology and Stem Cell Research Royal Netherlands Academy of Arts and Sciences (KNAW) Utrecht The Netherlands Broad Institute of MIT and Harvard Cambridge USA Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge USA

In this Article, a data processing error affected Fig. 3e and Extended Data Table 2; these errors have been corrected online.

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