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Microsystems & Nanoengineering 2020年第1期6卷 122-135页

作者： Chen Wang Xiaoxiao Song Weidong Fang Fang Chen Ioannis Zeimpekis Yuan Wang Aojie Quan Jian Bai Huafeng Liu Gerold Schropfer chris welham Michael Kraft College of Optical Science and Engineering Zhejiang UniversityHangzhou 310027P.R.China Department of Electrical Engineering and Computer Science University of LiegeLiege B-4000Belgium ESAT-MICAS University of LeuvenLeuven 3001Belgium PGMF and School of Physics Huazhong University of Science and TechnologyWuhan 430074P.R.China Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050P.R.China ORC University of SouthamptonSouthampton SO171BJUK Coventor—A Lam Research Company Villebon sur Yvette 91140France

This paper describes a novel,semiautomated design methodology based on a genetic algorithm(GA)using freeform geometries for microelectromechanical systems(MEMS)devices.The proposed method can design MEMS devices comprising freeform geometries and optimize such MEMS devices to provide high sensitivity,large bandwidth,and large fabrication tolerances.The proposed method does not require much computation time or memory.The use of freeform geometries allows more degrees of freedom in the design process,improving the diversity and performance of MEMS devices.A MEMS accelerometer comprising a mechanical motion amplifier is presented to demonstrate the effectiveness of the design approach.Experimental results show an improvement in the product of sensitivity and bandwidth by 100%and a sensitivity improvement by 141%compared to the case of a device designed with conventional orthogonal shapes.Furthermore,excellent immunities to fabrication tolerance and parameter mismatch are achieved.

关键词： accelerometer algorithm motion

Increasing Threat of Scarcity Prompts Rise in Water Recycling

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Engineering 2024年第2期33卷 6-8页

作者： chris Palmer Senior Technology Writer

In January 2018,construction wrapped on Salesforce Tower(Fig.1),a 61-story office building that now dominates the skyline of San Francisco,CA,USA.In addition to being the tallest building in the city,Salesforce Tower is the largest structure in the world with an onsite water recycling system.Built by the Australian com-pany Aquacell(Milton,NSW,Australia),the system cleans 113 m^(3)of sewage,sink,shower,and other wastewater each day for use in irrigation and flushing toilets,saving an estimated 35000 m?of water anmually[1].The building is just one of dozens in San Fran-cisco outitted with their own water recycling systems,thanks to a city mandate enacted in 2015[1].

关键词： cycling wastewater recycling

Universal insertion of molecules in ionic compounds under pressure

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National Science Review 2024年第1期11卷 120-128页

作者： Feng Peng Yanming Ma chris J.Pickard Hanyu Liu Maosheng Miao College of Physics and Electronic Information Luoyang Normal University Department of Chemistry and Biochemistry California State University Northridge State Key Laboratory of Superhard Materials & Key Laboratory of Material Simulation Methods and Software of Ministry of Education College of Physics Jilin University International Center of Future Science Jilin University Department of Materials Science & Metallurgy University of Cambridge Advanced Institute for Materials Research Tohoku University Department of Earth Science University of California Santa Barbara

Using first-principles calculations and crystal structure search methods, we found that many covalently bonded molecules such as H2, N2, CO2, NH3, H2O and CH4may react with NaC l, a prototype ionic solid,and form stable compounds under pressure while retaining their molecular structure. These molecules,despite whether they are homonuclear or heteronuclear, polar or non-polar, small or large, do not show strong chemical interactions with surrounding Na and Cl ions. In contrast, the most stable molecule among all examples, N2, is found to transform into cyclo-N5-anions while reacting with NaC l under high pressures. It provides a new route to synthesize pentazolates, which are promising green energy materials with high energy density. Our work demonstrates a unique and universal hybridization propensity of covalently bonded molecules and solid compounds under pressure. This surprising miscibility suggests possible mixing regions between the molecular and rock layers in the interiors of large planets.

关键词： molecule-solid hybrid materials high-pressure crystal structure prediction density functional theory planet interior

Attitude control of multi-spacecraft systems on SO(3)with stochastic links failure

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Chinese Journal of Aeronautics 2024年第3期37卷 320-331页

作者： KANG Zeyu SHEN Qiang WU Shufan chris J.DAMAREN MU Zhongcheng School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China Institute for Aerospace Studies University of TorontoTorontoOntario M3H 5T6Canada

In this paper,for Multi-Spacecraft System(MSS)with a directed communication topology link and a static virtual leader,a controller is proposed to realize attitude consensus and attitude stabilization with stochastic links failure and actuator saturation.First,an MSS attitude error model suitable for a directed topology link and with a static virtual leader based on SO(3)is derived,which considers that the attitude error on SO(3)cannot be defined based on algebraic subtraction.Then,we design a controller to realize the MSS on SO(3)with attitude consensus and attitude stabilization under stochastic links failure and actuator saturation.Finally,the simulation results of a multi-spacecraft system with stochastic links failure and a static virtual leader spacecraft are demonstrated to illustrate the efficiency of the attitude controller.

关键词： Multi-spacecraft systems Attitude consensus Attitude stabilization Stochastic links failure Super-martingale convergence

Suppressive effects of exercise-conditioned serum on cancer cells:A narrative review of the influence of exercise mode,volume,and intensity

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Journal of Sport and Health Science 2024年第4期13卷 484-498,F0003页

作者： Francesco Bettariga Dennis R.Taaffe Daniel A.Galvao chris Bishop Jin-Soo Kim Robert U.Newton Exercise Medicine Research Institute Edith Cowan UniversityJoondalupWA 6027Australia School of Medical and Health Sciences Edith Cowan UniversityJoondalupWA 6027Australia London Sport Institute School of Science and TechnologyMiddlesex UniversityLondonNW44BTUK School of Human Movement and Nutrition Sciences University of QueenslandSt.LuciaQLD 4072Australia

Cancer is a major cause of morbidity and mortality worldwide,and the incidence is increasing,highlighting the need for effective strategies to treat this disease.Exercise has emerged as fundamental therapeutic medicine in the management of cancer,associated with a lower risk of recur-rence and increased survival.Several avenues of research demonstrate reduction in growth,proliferation,and increased apoptosis of cancer cells,including breast,prostate,colorectal,and lung cancer,when cultured by serum collected after exercise in vitro(i.e.,the cultivation of cancer cell lines in an experimental setting,which simpliﬁes the biological system and provides mechanistic insight into cell responses).The underlying mechanisms of exercise-induced cancer suppressive effects may be attributed to the alteration in circulating factors,such as skeletal muscle-induced cytokines(i.e.,myokines)and hormones.However,exercise-induced tumor suppressive effects and detailed information about training interventions are not well investigated,constraining more precise application of exercise medicine within clinical oncology.To date,it remains unclear what role different training modes(i.e.,resistance and aerobic training)as well as volume and intensity have on exercise-condi-tioned serum and its effects on cancer cells.Nevertheless,the available evidence is that a single bout of aerobic training at moderate to vigorous intensity has cancer suppressive effects,while for chronic training interventions,exercise volume appears to be an inﬂuential candidate driving cancer inhibitory effects regardless of training mode.Insights for future research investigating training modes,volume and intensity are provided to further our understanding of the effects of exercise-conditioned serum on cancer cells.

关键词： Cancer cells High intensity interval training Moderate intensity continuous training Resistance training Myokines

Eco-evolutionary evidence for the global diversity pattern of Cycas(Cycadaceae)

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Journal of Integrative Plant Biology 2024年第6期66卷 1170-1191页

作者： Jian Liu Anders J.Lindstrom Yiqing Gong Shanshan Dong Yusheng(chris) Liu Shouzhou Zhang Xun Gong CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences Department of Economic Plants and Biotechnology Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of BotanyChinese Academy of Sciences University of Chinese Academy of Sciences Global Biodiversity Conservancy Key Laboratory of Southern Subtropical Plant Diversity Fairy Lake Botanical Garden Shenzhen & Chinese Academy of Sciences Department of Earth and Environmental Sciences Indiana University-Indianapolis

The evolution of the latitudinal diversity gradient(LDG), characterized by a peak in diversity toward the tropics, has captured significant attention in evolutionary biology and ecology.However, the inverse LDG(i-LDG) mechanism,wherein species richness increases toward the poles, remains inadequately explored. Cycads are among one of the oldest lineages of extant seed plants and have undergone extensive diversification in the tropics. Intriguingly, the extant cycad abundance exhibits an i-LDG pattern, and the underlying causes for this phenomenon remain largely elusive. Here,using 1,843 nuclear genes from a nearly complete sampling, we conducted comprehensive phylogenomic analyses to establish a robust species-level phylogeny for Cycas, the largest genus within cycads. We then reconstructed the spatial-temporal dynamics and integrated global environmental data to evaluate the roles of species ages, diversification rates,contemporary environment, and conservatism to ancestral niches in shaping the i-LDG pattern. We found Cycas experienced decreased diversification rates, coupled with the cooling temperature since its origin in the Eocene from continental Asia. Different regions have distinctively contributed to the formation of i-LDG for Cycas, with the northern hemisphere acting as evolutionary museums and the southern hemisphere serving as cradles. Moreover, water-related climate variables,specifically precipitation seasonality and potential evapotranspiration, were identified as paramount factors constraining Cycas species richness in the rainforest biome near the equator. Notably, the adherence to ancestral monsoonal climates emerges as a critical factor in sustaining the diversity pattern. This study underscores the imperative of integrating both evolutionary and ecological approaches to comprehensively unravel the mechanisms underpinning global biodiversity patterns.

关键词： cycads latitudinal diversity gradient niche conservatism spatiotemporal diversification species richness

Chronic effects of stretching on range of motion with consideration of potential moderating variables:A systematic review with meta-analysis

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Journal of Sport and Health Science 2024年第2期13卷 186-194页

作者： Andreas Konrad Shahab Alizadeh Abdolhamid Daneshjoo Saman Hadjizadeh Anvar Andrew Graham Ali Zahiri Reza Goudini chris Edwards Carina Scharf David George Behm Institute of Human Movement Science Sport and HealthGraz UniversityGraz A-8010Austria School of Human Kinetics and Recreation Memorial University of NewfoundlandSt.John’sNL A1C 5S7Canada Department of Sport Injuries and Corrective Exercises Faculty of Sport SciencesShahid Bahonar University of KermanKerman 76169-13439Iran

Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence on improvements in flexibility.Thus,the purpose of this metaanalysis was to investigate the effects of stretch training on ROM in healthy participants by considering potential moderating variables,such as stretching technique,intensity,duration,frequency,and muscles stretched,as well as sex-specific,age-specific,and/or trained state-specific adaptations to stretch training.Methods:We searched through PubMed,Scopus,Web of Science,and SportDiscus to find eligible studies and,finally,assessed the results from 77 studies and 186 effect sizes by applying a random-effect meta-analysis.Moreover,by applying a mixed-effect model,we performed the respective subgroup analyses.To find potential relationships between stretch duration or age and effect sizes,we performed a meta-regression.Results:We found a significant overall effect,indicating that stretch training can increase ROM with a moderate effect compared to the controls(effect size=-1.002;Z=-12.074;95%confidence interval:-1.165 to-0.840;p<0.001;I^(2)=74.97).Subgroup analysis showed a significant difference between the stretching techniques(p=0.01)indicating that proprioceptive neuromuscular facilitation and static stretching produced greater ROM than did ballistic/dynamic stretching.Moreover,there was a significant effect between the sexes(p=0.04),indicating that females showed higher gains in ROM compared to males.However,further moderating analysis showed no significant relation or difference.Conclusion:When the goal is to maximize ROM in the long term,proprioceptive neuromuscular facilitation or static stretching,rather than ballistic/dynamic stretching,should be applied.Something to consider in future research as well as sports practice is that neither volume,intensity,nor frequency of stretching were found to play a significant role in ROM yields.

关键词： Flexibility Long-term stretching Stretch training

“泰坦”号潜水器--通向死亡的“海洋之门”

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Engineering 2024年第1期32卷 1-3页

作者： chris Palmer Senior Technology Writer

Early on the morning of June 18,2023,far off the shore of Newfoundland,Canada,the Titan deep-sea submersible began its descent into the depths of the North Atlantic.Aboard was Titan’s inventor and pilot,Stockton Rush,along with four“mission specialists,”several of whom may have paid as much as 250000 USD to accompany Rush on a voyage to the site of the infamous Titanic shipwreck on the ocean floor.About two hours later.

关键词：泰坦 depths ocean

Intelligent Recognition Using Ultralight Multifunctional Nano‑Layered Carbon Aerogel Sensors with Human‑Like Tactile Perception

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Nano-Micro Letters 2024年第1期16卷 172-186页

作者： Huiqi Zhao Yizheng Zhang Lei Han Weiqi Qian Jiabin Wang Heting Wu Jingchen Li Yuan Dai Zhengyou Zhang chris RBowen Ya Yang CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro‑Nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400People’s Republic of China Tencent Robotics X Shenzhen 518054People’s Republic of China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049People’s Republic of China Department of Mechanical Engineering University of BathBath BA27AKUK Center on Nanoenergy Research School of Physical Science and TechnologyGuangxi UniversityNanning 530004People’s Republic of China

Humans can perceive our complex world through multi-sensory fusion.Under limited visual conditions,people can sense a variety of tactile signals to identify objects accurately and rapidly.However,replicating this unique capability in robots remains a significant challenge.Here,we present a new form of ultralight multifunctional tactile nano-layered carbon aerogel sensor that provides pressure,temperature,material recognition and 3D location capabilities,which is combined with multimodal supervised learning algorithms for object recognition.The sensor exhibits human-like pressure(0.04–100 kPa)and temperature(21.5–66.2℃)detection,millisecond response times(11 ms),a pressure sensitivity of 92.22 kPa^(−1)and triboelectric durability of over 6000 cycles.The devised algorithm has universality and can accommodate a range of application scenarios.The tactile system can identify common foods in a kitchen scene with 94.63%accuracy and explore the topographic and geomorphic features of a Mars scene with 100%accuracy.This sensing approach empowers robots with versatile tactile perception to advance future society toward heightened sensing,recognition and intelligence.

关键词： Multifunctional sensor Tactile perception Multimodal machine learning algorithms Universal tactile system Intelligent object recognition

Efficiency of a Modular Cleanroom for Space Applications

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Fluid Dynamics & Materials Processing 2024年第3期20卷 547-562页

作者： Matthew R.Coburn Charlie Young chris Smith Graham Schultz Miguel Robayo Zheng-Tong Xie Faculty of Engineering and Physical Sciences University of SouthamptonSouthamptonSO171BJUK Plastron UK Ltd. Westcott Venture ParkWestcottHP180XBUK Renewable Energy Group University of ExeterExeterTR109FEUK

A prototype cleanroom for hazardous testing and handling of satellites prior to launcher encapsulation,satisfying the ISO8 standard has been designed and analyzed in terms of performances.Unsteady Reynolds Averaged Navier-Stokes(URANS)models have been used to study the related flow field and particulate matter(PM)dispersion.The outcomes of the URANS models have been validated through comparison with equivalent large-eddy simulations.Special attention has been paid to the location and shape of the air intakes and their orientation in space,in order to balance the PM convection and diffusion inside the cleanroom.Forming a cyclone-type flow pattern inside the cleanroom is a key to maintaining a high ventilation efficiency.

关键词： Diffuser LES PM RANS unsteady flow exponential decay