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The 2022 report of the Lancet Countdown on health and climate change: health at the mercy of fossil fuels (vol 400, pg 1619, 2022)

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LANCET 2022年第10365期400卷 1766-1766页

作者： Romanello, M. Di Napoli, C. Drummond, P. Institute for Global Health University College London London UK School of Agriculture Policy and Development University of Reading Reading UK Institute for Sustainable Resources University College London London UK Department of Global Health Centre for Health and the Global Environment University of Washington Seattle WA USA UCL Energy Institute University College London London UK Department of Health Sciences University of York York UK Department of Meteorology University of Reading Reading UK Institute for Risk and Disaster Reduction University College London London UK School of Earth and Environment University of Leeds Leeds UK Centre on Climate Change and Planetary Health London School of Hygiene & Tropical Medicine London UK School of Population Health University of Melbourne Melbourne VIC Australia Department of Earth System Science Tsinghua University Beijing China Mercator Research Institute on Global Commons and Climate Change Berlin Germany Department of Environment Climate Change and Health World Health Organization Geneva Switzerland Institute of Environmental Sciences University of Geneva Geneva Switzerland Cardiovascular Epidemiology Unit Department of Public Health & Primary Care University of Cambridge Cambridge UK School of Government University of Birmingham Birmingham UK Economic Analysis of Climate Impacts and Policy Division Centro Euro-Mediterraneo sui Cambiamenti Climatici Venice Italy Institute for Environmental Design and Engineering University College London London UK Natural Resources Institute University of Greenwich London UK Department of Environmental Health Sciences and Yale Center on Climate Change and Health Yale University New Haven CT USA Department of Civil and Environmental Engineering Northeastern University Boston MA USA Department of Fish and Wildlife Conservation Virginia Polytechnic Institute and State University Blacksburg VA USA Department of Geography University College London London UK NU

With advancements in the science of detection and attribution studies, the influence of climate change over many events has now been quantified. Because of the rapidly increasing temperatures, vulnerable populations (adults older than 65 years, and children younger than one year of age) were exposed to 3·7 billion more heatwave days in 2021 than annually in 1986–2005 (indicator 1.1.2), and heat-related deaths increased by 68% between 2000–04 and 2017–21 (indicator 1.1.5), a death toll that was significantly exacerbated by the confluence of the COVID-19 pandemic. Despite the local cooling and overall health benefits of urban greenspaces, only 277 (27%) of 1038 global urban centres were at least moderately green in 2021 (indicator 2.2.3), and the number of households with air conditioning increased by 66% from 2000 to 2020, a maladaptive response that worsens the energy crisis and further increases urban heat, air pollution, and greenhouse gas emissions. [...]millions of people do not have access to the energy needed to keep their homes at healthy temperatures, preserve food and medication, and meet the seventh Sustainable Development Goal (to ensure access to affordable, reliable, sustainable, and modern energy for all). Aggravating this situation even further, governments continue to incentivise fossil fuel production and consumption: 69 (80%) of 86 countries reviewed had net-negative carbon prices (ie, provided a net subsidy to fossil fuels) for a net total of US$400 billion

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Agents, subsystems, and the conservation of information

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arXiv 2018年

作者： Chiribella, Giulio Department of Computer Science University of Oxford Parks Road Oxford United Kingdom Canadian Institute for Advanced Research CIFAR Program in Quantum Information Science Department of Computer Science University of Hong Kong Pokfulam Road Hong Kong HKU Shenzhen Institute of Research and Innovation Kejizhong 2nd Road Shenzhen China

Dividing the world into subsystems is an important component of the scientific method. The choice of subsystems, however, is not defined a priori. Typically, it is dictated by experimental capabilities, which may be different for different agents. Here we propose a way to define subsystems in general physical theories, including theories beyond quantum and classical mechanics. Our construction associates every agent A with a subsystem SA, equipped with its set of states and its set of transformations. In quantum theory, this construction accommodates the notion of subsystems as factors of a tensor product Hilbert space, as well as the notion of subsystems associated to a subalgebra of operators. Classical systems can be interpreted as subsystems of quantum systems in different ways, by applying our construction to agents who have access to different sets of operations, including multiphase covariant channels and certain sets of free operations arising in the resource theory of quantum coherence. After illustrating the basic definitions, we restrict our attention to closed systems, that is, systems where all physical transformations act invertibly and where all states can be generated from a fixed initial state. For closed systems, we propose a dynamical definition of pure states, and show that all the states of all subsystems admit a canonical purification. This result extends the purification principle to a broader setting, in which coherent superpositions can be interpreted as purifications of incoherent mixtures. Copyright © 2018, The Authors. All rights reserved.

关键词： Purification

Quantum communication in a superposition of causal orders

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arXiv 2018年

作者： Salek, Sina Ebler, Daniel Chiribella, Giulio Department of Computer Science University of Oxford Parks Road United Kingdom United Kingdom Department of Computer Science University of Hong Kong Pokfulam Road Hong Kong Canadian Institute for Advanced Research CIFAR Program in Quantum Information Science TorontoONM5G 1Z8 Canada

Quantum mechanics allows for situations where the relative order between two processes is entangled with a quantum degree of freedom. Here we show that such entanglement can enhance the ability to transmit quantum information over noisy communication channels. We consider two completely dephasing channels, which in normal conditions are unable to transmit any quantum information. We show that, when the two channels are traversed in an indefinite order, a quantum bit sent through them has a 25% probability to reach the receiver without any error. For partially dephasing channels, a similar advantage takes place deterministically: The amount of quantum information that can travel through two channels in a superposition of orders can be larger than the amount of quantum information that can travel through each channel individually. Copyright © 2018, The Authors. All rights reserved.

关键词： Quantum optics

Spoof-Fluid-Spoof Acoustic Waveguide and its Applications for Sound Manipulation

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Physical Review Applied 2019年第5期12卷 054014-054014页

作者： Norbert Cselyuszka Andrea Alù Nikolina Janković BioSense Institute University of Novi Sad Novi Sad Serbia Silicon Austria Labs Sensor System Microsystem Technologies Villach Austria Department of Electrical and Computer Engineering The University of Texas at Austin Austin Texas 78712 USA Photonics Initiative Advanced Science Research Center City University of New York New York New York 10031 USA Physics Program Graduate Center City University of New York New York New York 10026 USA Department of Electrical Engineering City College of New York New York New York 10031 USA

We explore the implementation of a spoof–fluid-spoof (SFS) acoustic waveguide, which is the acoustic analogue of a metal-insulator–metal waveguide in plasmonics. The proposed structure consists of two corrugated rigid surfaces separated by a fluid layer. The properties of the guided acoustic modes between corrugated rigid parallel plates are analytically and numerically studied by deriving their dispersion relation and through a careful analysis of symmetric and antisymmetric modes supported by this structure. Similar to plasmonic waveguides, it is shown that the dispersion relation of the proposed SFS acoustic waveguide, and the supported group and phase velocities, can be largely controlled by changes in the geometrical parameters of the waveguide, opening the possibility for application of this technology for acoustic delay lines, modulators, and sensors. The analytical and numerical results are validated through experiments in a controlled environment.

关键词： Acoustic measurements Acoustic metamaterials Acoustic modeling Acoustic wave phenomena Plasmonics Surface plasmon polariton Waveguides Surface acoustic wave

[email protected] core-shell nanoparticles as a p-type gas sensor: Novel synthesis, characterization, and their gas sensing properties with sensing mechanism

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Sensors and Actuators B: Chemical 2018年 268卷 223-231页

作者： Sanjit Manohar Majhi Gautam Kumar Naik Hu-Jun Lee Ho-Geun Song Cheul-Ro Lee In-Hwan Lee Yeon-Tae Yu Division of Advanced Materials Engineering and Research Center for Advanced Materials Development College of Engineering Chonbuk National University Jeonju 561-756 South Korea Electrical Engineering Program Computer Electrical and Mathematical Science and Engineering Division King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia Ogam Technology Jeonju 54882 South Korea Department of Materials Science and Engineering Korea University Seoul 02841 South Korea

In this work, [email protected] core-shell nanoparticles (C-S NPs) as a p-type gas sensing material was synthesized by a facile wet-chemical method, and evaluated their gas sensing properties as compared to the pristine NiO NPs gas sensors. Transmission electron microscope (TEM) results exhibited the well-dispersed formation of [email protected] C-S NPs having the total size of 70–120 nm and NiO shells having 30–50 nm thickness. The C-S morphology as well as the overall particle sizes are unchanged even at 500 °C. The gas sensing result reveals that the response of [email protected] C-S NPs gas sensor is higher than pristine NiO NPs gas sensor for 100 ppm of ethanol at 200 °C operating temperature. The baseline resistance in the air for [email protected] C-S NPs sensor is lowered as compared to pristine NiO NPs, which is due to the increased number of holes as charge carriers in [email protected] C-S NPs. The high response of [email protected] core-shell NPs as compared to pristine NiO NPs is attributed to electronic and chemical sensitization effects of Au. In [email protected] C-S structure, the contact between metal (Au) and semiconductor (NiO) formed a Schottky junction since Au metal acted as electron acceptor, a withdrawal of electrons from NiO by Au metal core leaved behind number of holes as charge carriers in [email protected] C-S NPs. Therefore, the baseline resistance of [email protected] C-S NPs greatly decreased than pristine NiO NPs, as a result the [email protected] C-S NPs showed higher response. On the other hand, in chemical sensitization effect, Au NPs catalyzed to dissociate O 2 molecules into ionic species. This work will give some clue to the researchers for the further development of p-type based C-S NPs sensors.

关键词： [email protected] Core-shell NPs Baseline resistance Sensitivity [email protected]

Building a quantum engineering undergraduate program

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arXiv 2021年

作者： Asfaw, Abraham Blais, Alexandre Brown, Kenneth R. Candelaria, Jonathan Cantwell, Christopher Carr, Lincoln D. Combes, Joshua Debroy, Dripto M. Donohue, John M. Economou, Sophia E. Edwards, Emily Fox, Michael F.J. Girvin, Steven M. Ho, Alan Hurst, Hilary M. Jacob, Zubin Johnson, Blake R. Johnston-Halperin, Ezekiel Joynt, Robert Kapit, Eliot Klein-Seetharaman, Judith Laforest, Martin Lewandowski, H.J. Lynn, Theresa W. McRae, Corey Rae H. Merzbacher, Celia Michalakis, Spyridon Narang, Prineha Oliver, William D. Palsberg, Jens Pappas, David P. Raymer, Michael G. Reilly, David J. Saffman, Mark Searles, Thomas A. Shapiro, Jeffrey H. Singh, Chandralekha IBM Quantum IBM T. J. Watson Research Center Yorktown HeightsNY United States Institut Quantique Département de Physique Université de Sherbrooke SherbrookeQCJ1K 2R1 Canada Canadian Institute for Advanced Research TorontoONM5G 1M1 Canada The Duke Quantum Center Department of Physics Department of Electrical and Computer Engineering Department of Chemistry Duke University DurhamNC27708 United States SystemX Program Department of Electrical Engineering Stanford University StanfordCA94305 United States Department of Physics and Astronomy University of Southern California Los AngelesCA90089 United States The Quantum Engineering Program Department of Physics Colorado School of Mines GoldenCO80401 United States The Department of Electrical Computer and Energy Engineering University of Colorado Boulder BoulderCO80309 United States The Institute for Quantum Computing University of Waterloo WaterlooONN2L 3G1 Canada The Department of Physics Virginia Tech BlacksburgVA24061 United States The IQUIST University of Illinois Urbana-Champaign UrbanaIL61801 United States JILA National Institute of Standards and Technology The University of Colorado BoulderCO80309 United States Department of Physics University of Colorado Boulder BoulderCO80309 United States The Department of Physics Imperial College London Prince Consort Road LondonSW7 2AZ United Kingdom The Yale Quantum Institute Department of Physics Yale University New HavenCT06520 United States Google Research VeniceCA90291 United States The Department of Physics & Astronomy San José State University San JoséCA95192 United States The School of Electrical and Computer Engineering Purdue University Indiana West Lafayatte47907 United States The Department of Physics The Ohio State University ColumbusOH43210 United States The Department of Physics University of Wisconsin-Madison 1150 University Avenue MadisonWI53706 United States The Quantitative Biosciences and Engineering

The rapidly growing quantum information science and engineering (QISE) industry will require both quantum-aware and quantum-proficient engineers at the bachelor's level. We provide a roadmap for building a quantum engineering education program to satisfy this need. For quantum-aware engineers, we describe how to design a first quantum engineering course accessible to all STEM students. For the education and training of quantum-proficient engineers, we detail both a quantum engineering minor accessible to all STEM majors, and a quantum track directly integrated into individual engineering majors. We propose that such programs typically require only three or four newly developed courses that complement existing engineering and science classes available on most larger campuses. We describe a conceptual quantum information science course for implementation at any post-secondary institution, including community colleges and military schools. QISE presents extraordinary opportunities to work towards rectifying issues of inclusivity and equity that continue to be pervasive within engineering. We present a plan to do so and describe how quantum engineering education presents an excellent set of education research opportunities. Finally, we outline a hands-on training plan on quantum hardware, a key component of any quantum engineering program, with a variety of technologies including optics, atoms and ions, cryogenic and solid-state technologies, nanofabrication, and control and readout electronics. Our recommendations provide a flexible framework that can be tailored for academic institutions ranging from teaching and undergraduate-focused two- and four-year colleges to research-intensive universities. © 2021, CC BY.

关键词： Engineering education

One-way hyperbolic metasurfaces based on synthetic motion

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arXiv 2019年

作者： Mazor, Yarden Alù, Andrea Department of Electrical and Computer Engineering University of Texas Austin AustinTX78712 United States Physics Program Graduate Center City University of New York New YorkNY10026 United States Photonics Initiative Advanced Science Research Center City University New York New YorkNY10031 United States Department of Electrical Engineering City College New York New YorkNY10031 United States

Moving metasurfaces support guided waves exhibiting unusual optical properties, including strong anisotropy, nonreciprocity and hyperbolic dispersion. However, for these phenomena to be noticeable, high speeds are typically required, challenging their practical implementation. Here, we show a viable route towards the realization of one-way hyperbolic propagation in metasurfaces placed synthetically in motion through traveling-wave space-time modulation. In addition to non-reciprocal hyperbolic propagation, the proposed time-modulation scheme induces additional exotic opportunities for nanophotonic systems, such as efficient nonreciprocal frequency conversion and mode transfer. Copyright © 2019, The Authors. All rights reserved.

关键词： Guided electromagnetic wave propagation

Three dimensions, two microscopes, one code: Automatic differentiation for X-ray nanotomography beyond the depth of focus limit

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arXiv 2019年

作者： Du, Ming Nashed, Youssef S. G. Kandel, Saugat Gursoy, Doga Jacobsen, Chris Department of Materials Science Northwestern University EvanstonIL60208 United States Mathematics and Computer Science Division Argonne National Laboratory LemontIL60439 United States Applied Physics Program Northwestern University EvanstonIL60208 United States Advanced Photon Source Argonne National Laboratory ArgonneIL60439 United States Department of Physics and Astronomy Northwestern University EvanstonIL60208 United States Chemistry of Life Processes Institute Northwestern University EvanstonIL60208 United States

Conventional tomographic reconstruction algorithms assume that one has obtained pure projection images, involving no within-specimen diffraction effects nor multiple scattering. Advances in X-ray nanotomography are leading towards the violation of these assumptions, by combining the high penetration power of X-rays which enables thick specimens to be imaged, with improved spatial resolution which decreases the depth of focus of the imaging system. We describe a reconstruction method where multiple scattering and diffraction effects in thick samples are modeled by multislice propagation, and the 3D object function is retrieved through iterative optimization. We show that the same proposed method works for both full-field microscopy, and for coherent scanning techniques like ptychography. Our implementation utilizes the optimization toolbox and the automatic differentiation capability of the open-source deep learning package TensorFlow, which demonstrates a much straightforward way to solve optimization problems in computational imaging, and endows our program great flexibility and portability. Copyright © 2019, The Authors. All rights reserved.

关键词： Computational Imaging

Quasielectrostatic Wave Propagation Beyond the Delay-Bandwidth Limit in Switched Networks

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Physical Review X 2019年第3期9卷 031015-031015页

作者： Mykhailo Tymchenko Dimitrios Sounas Aravind Nagulu Harish Krishnaswamy Andrea Alù Department of Electrical and Computer Engineering The University of Texas at Austin 1 University Station C0803 Austin Texas 78712 USA Department of Electrical and Computer Engineering Wayne State University Detroit Michigan 48202 USA Department of Electrical Engineering Columbia University 1300 South West Mudd 500 West 120th Street New York New York 10027 USA Photonics Initiative Advanced Science Research Center City University of New York New York New York 10031 USA Physics Program Graduate Center City University of New York New York New York 10026 USA Department of Electrical Engineering City College of New York New York New York 10031 USA

The delay-bandwidth limit implies a stringent trade-off between the time delay, bandwidth, and propagation distance of an electromagnetic signal. Here, we show that temporal modulation can overcome this constraint, enabling extremely broadband wave propagation with close-to-zero group velocity dispersion in switched multipath electronic networks. Contrary to time-invariant waveguides, in which wave propagation implies a delicate balance between electric and magnetic stored energies, in such modulated networks the stored energy is largely electrostatic in nature. We show that in this case the phase and group velocities become independent of the properties of their constituent elements, and they are controlled only by the modulation scheme. Based on these findings, we provide practical designs of deeply subwavelength CMOS-compatible reciprocal and nonreciprocal microwave components, such as delay lines, phase shifters, couplers, and circulators. The obtained results also explicitly show that temporally modulated systems are not bound by constraints of time-invariant systems and can achieve arbitrarily large delay-bandwidth products.

关键词： Metamaterials