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World Journal of Emergency Medicine 2021年第3期12卷 247-248页

作者： Xian-bao Liu Jia-qi Fan Ye-ming xu Yu-chao guo Cheng Li jian-guo xu jian-an Wang Department of Cardiology the Second Affi liated Hospital Zhejiang University School of MedicineHangzhou 310009China Zhejiang University School of Medicine Hangzhou 310058China Department of Electrocardiography the Second Affi liated Hospital Zhejiang University School of MedicineHangzhou 310009China

Dear editor,Transcatheter aortic valve replacement(TAVR)is a safe and effective first-line therapeutic management for patients with severe aortic *** evidence of multiple randomized clinical trials proves the safety and efficacy of TAVR in patients.[1-2]However,new-onset conduction disorders,atrial fi brillation,and acute coronary syndrome are still common complications after TAVR *** life-threatening complications such as myocardial infarction may result in fatal clinical *** COVID-19 pandemic makes periodic and timely follow-ups for patients after TAVR more diffi *** ambulatory electrocardiogram(AECG)monitoring system by a smart wearable device has recently emerged as a tool to monitor cardiac events before and after TAVR.[3]Smartwatches can monitor and record multiple biometric parameters,like heart rate,step counts,sleep cycles,oxygen saturation,and analyze QRS complexes and P waves after triggering incidences。

关键词： infarction smart editor

Dynamic impedance of piles in visco-elastic material considering axial loads

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Journal of Central South University of Technology 2005年第Z1期12卷 162-167页

作者： jianG jian-guo ZHOU xu-hong ZHANG Jia-sheng School of Civil Engineering and Architecture Central South University Changsha 410075 China School of Civil Engineering and Architecture Chang''an University Xi''an 710064 China School of Civil Engineering and Architecture Central South University Changsha 410075 China

The dynamic impedance function of pile in visco-elastie material considering axial loads under lateral dynamic force was analyzed, and the beam dynamic differential equation was used to induce the dynamic impedance function. After analyzing the edge conditions, the dynamic impedance functions were deduced. Contrasted with the result that does not consider axial loads, the axial loads have obvious influence on the dynamic impedance *** the results show that the dimensionless prarmeter of the dynamic impedance will change from 6 % to 9 % when considering axial loads, and dimensionless prarmeter of the dynamic impedance of the coupling horizontal-sway will increase by 31 %.

关键词： impedance function dynamic analysis axial loads

Research on the fracture behavior of PBX under static tension

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Defence Technology（防务技术） 2014年第2期10卷 154-160页

作者： Hu guo Jing-run LUO Ping-an SHI jian-guo xu Institute of Systems Engineering China Academy of Engineering Physics

The fracture behavior of polymer-bonded explosive(PBX) seriously affects the safety and reliability of weapon *** effects of interface debonding and initial meso-damage on the fracture behavior of PBX under quasi-static tension are studied using numerical method.A twodimensional representative volume element(RVE) is established based on Voronoi model in which the component contents could be regulated and the particles are randomly distributed.A nonlinear damage model of polymer matrix relative to matrix depth between particles is *** results show that the simulated strain-stress relation is coincident with experiment *** is found that interface debonding leads to the nucleation and propagation of meso-cracks,and a main crack approximately perpendicular to the loading direction is generated *** interface debonding tends to occur in the interface perpendicular to the loading *** seems to be a phenomenon that strain softening and hardening alternatively appear around peak stress of stress and strain *** is shown that the initial damages of intragranular and interfacial cracks both decrease the modulus and failure stress,and the main crack tends to propagate toward the initial meso-cracks.

关键词：拉伸断裂行为 PBX 准静态界面裂纹损伤模型峰值应力裂纹传播武器系统

Ultralow-phase-noise and broadband frequency-hopping coupled optoelectronic oscillator under quiet point operation

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Photonics Research 2024年第8期12卷 1785-1793页

作者： HUI LIU MINGYANG guo TIAN ZHANG jian DAI KUN xu State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Advancements in microwave photonics have yielded novel approaches for generating high-purity microwave *** these,optoelectronic oscillators(OEOs)and coupled optoelectronic oscillators(COEOs)have demonstrated the capability to generate frequency-independent microwaves with exceptionally low phase ***,the tunability of the oscillators is rather limited due to the necessity for narrowband electronic bandpass filters,presenting challenges in achieving both wide and rapid tuning ***,we present a COEO featuring ultralow phase noise,flexible tuning capability,and high *** is achieved through a quiet point(QP)-operated harmonic mode-locked fiber laser,which effectively mitigates optical amplifier noise and supermode competition,thus significantly diminishing the necessity for ultra-narrow electronic *** to the liberated tuning ability,we present an oscillator that can be tuned from 2 GHz to 18 GHz,with phase noise as low as-140 d Bc/Hz at 10 k Hz under the QP *** then illustrate the practical application of the proposed oscillator in generating frequency-hopping signals with consistent spurious modes less than-85 d Bc,absolute phase noise below-135 d Bc/Hz at 10 k Hz,hopping resolution of 1.25 MHz,and fractional frequency stability below 6.1×10^(-12)at 1 s averaging time when locked to a *** presented COEO structure emerges as a compelling solution for agile and low-noise microwave sources in advanced wireless communication and radar systems.

关键词： optoelectronic tuning amplifier

Degradation of neonicotinoids with different molecular structures in heterogeneous peroxymonosulfate activation system through different oxidation pathways

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Chinese Chemical Letters 2024年第9期35卷 331-339页

作者： Ruonan guo Heng Zhang Changsheng guo Ningqing Lv Beidou Xi jian xu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China School of Environment Tsinghua UniversityBeijing 100084China

The elimination of neonicotinoids(NEOs)from water has been a research priority due to their threats to human health and *** this study,we established the heterogeneous peroxymonosulfate(PMS)activation system using manganese catalyst(Mn NC)and cobalt catalyst(Co NC)to trigger the nonradical oxidation and synergistic oxidation pathway,respectively to remove *** results showed that the nonradical oxidation system exhibited superior NEOs degradation *** composition of organic pollutants in wastewater significantly impacted subsequent degradation *** charge distribution and reaction sites of various NEOs were analyzed using density functional theory(DFT)calculations,and it demonstrated the electron distribution and activity of NEOs were significantly influenced by the type and number of *** group(–NO_(2))and cyanide group(–C≡N)were identified as strong electron-withdrawing groups and prone to be attacked by negatively charged *** transformation of NEOs was analyzed,and result showed that the C and N sites adjacent to the nitro group and cyanide group were more susceptible to oxidation attacks.S and N atoms,which possess strong electronegativity and high electron cloud density,were identified as key active sites in the degradation *** outcomes of this study provide valuable guidance for the oriented regulation of oxidation pathways towards efficient removal of NEOs in water.

关键词： Fenton-like processes Molecular structure Neonicotinoids Nonradical oxidation Degradation pathway

Unbound^(28)O,the heaviest oxygen isotope observed:a cutting-edge probe for testing nuclear models

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Nuclear Science and Techniques 2024年第2期35卷 1-2页

作者： jian-guo Li Bai-Shan Hu Shuang Zhang Fu-Rong xu School of Physics and State Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing 100871China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China

The beyond-dripline oxygen isotopes^(27,28)O were recently observed at RIKEN,and were found to be unbound decaying into^(24)O by emitting *** unbound feature of the heaviest oxygen isotope,^(28)O,provides an excellent test for stateof-the-art nuclear *** atomic nucleus is a self-organized quantum manybody system comprising specific numbers of protons Z and neutrons N.

关键词： testing quantum system

Exact Box-Constrained Economic Operating Region for Power Grids Considering Renewable Energy Sources

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 514-523页

作者： Huating xu Bin Feng Chutong Wang Chuangxin guo jian Qiu Mingyang Sun College of Electrical Engineering Zhejiang UniversityHangzhou 310027China Department of Control Science and Engineering Zhejiang UniversityHangzhou 310027China

The growing integration of renewable energy sources manifests as an effective strategy for reducing carbon emissions. This paper strives to efficiently approximate the set of optimal scheduling plans(OSPs) to enhance the performance of the steady-state adaptive cruise method(SACM) of power grid, improving the ability of dealing with operational uncertainties. Initially, we provide a mathematical definition of the exact boxconstrained economic operating region(EBC-EOR) for the power grid and its dispatchable components. Following this, we introduce an EBC-EOR formulation algorithm and the corresponding bi-level optimization models designed to explore the economic operating boundaries. In addition, we propose an enhanced big-M method to expedite the computation of the EBCEOR. Finally, the effectiveness of the EBC-EOR formulation, its economic attributes, correlation with the scheduling plan underpinned by model predictive control, and the significant improvement in computational efficiency(over twelvefold) are verified through case studies conducted on two test systems..

关键词： Exact box-constrained economic operating region(EBC-EOR) big-M method intelligent scheduling steady-state adaptive cruise uncertainty renewable energy source

Development of Zn^(2+)-controlled expression system for lactic acid bacteria and its application in engineered probiotics

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Synthetic and Systems Biotechnology 2024年第1期9卷 152-158页

作者： Xiaoning xu Lingwen Zhang Yue Cui jian Kong Tingting guo State Key Laboratory of Microbial Technology Shandong UniversityNo.72 Binhai RoadQingdao266237PR China

Lactococcus lactis and Streptococcus thermophilus are considered as ideal chassis of engineered probiotics,while food-grade genetic tools are limited in those ***,a Zn^(2+)-controlled gene expression(ZICE)system was identified in the genome of *** CGMCC7.179,including a transcriptional regulator sczAst and a promoter region of cation transporter czcD(PczcDst).Specific binding of the SczAst to the palindromic sequences in PczcDst was demonstrated by EMSA analysis,suggesting the regulation role of SczAst on *** evaluate their possibility to control gene expression in vivo,the sczAst-PczcDst was employed to drive the expression of green fluorescence protein(GFP)gene in *** NZ9000 and *** CGMCC7.179,*** of the transformants could express GFP under Zn^(2+)induction,while no fluorescence without Zn^(2+)*** optimal conditions,Zn^(2+)was used at a final concentration of 0.8 mM in *** and 0.16 mM in *** at OD600 close to 0.4,and omitting yeast extract powder in the medium unexpectedly improved GFP expression level by *** the help of the ZICE system,engineered *** and *** strains were constructed to secret cytokine interleukin-10(IL-10)with immunogenicity,and the IL-10 content in the supernatant of the engineered *** was 59.37%of that under the nisin controlled expression *** study provided a tightly controlled expression system by the food-grade inducer Zn^(2+),having potential in development of engineered probiotics.

关键词： Lactococcus lactis Streptococcus thermophilus Food-grade expression system Engineered probiotic

Prediction of oxygen concentration and temperature distribution in loose coal based on BP neural network

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Mining Science and Technology 2009年第2期19卷 216-219页

作者： ZHANG Yong-jian WU guo-guang xu Hong-feng MENG Xian-liang WANG Guang-you School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

An effective method for preventing spontaneous combustion of coal stockpiles on the ground is to control the air-flow in loose coal. In order to determine and predict accurately oxygen concentrations and temperatures within coal stockpiles, it is vital to obtain information of self-heating conditions and tendencies of spontaneous coal combustion. For laboratory conditions, we designed our own experimental equipment composed of a control-heating system, a coal column and an oxygen concentration and temperature monitoring system, for simulation of spontaneous combustion of block coal （13-25 mm） covered with fine coal （0-3 mm）. A BP artificial neural network （ANN） with 150 training samples was gradually established over the course of our experiment. Heating time, relative position of measuring points, the ratio of fine coal thickness, artificial density, voidage and activation energy were selected as input variables and oxygen concentration and temperature of coal column as output variables. Then our trained network was applied to predict the trend on the untried experimental data. The results show that the oxygen concentration in the coal column could be reduced below the minimum still able to induce spontaneous combustion of coal - 6% by covering the coal pile with fine coal, which would meet the requirement to prevent spontaneous combustion of coal stockpiles. Based on the prediction of this ANN, the average errors of oxygen concentration and temperature were respectively 0.5% and 7 ℃, which meet actual tolerances. The implementation of the method would provide a practical guide in understanding the course of self-heating and spontaneous combustion of coal stockpiles.

关键词： loose coal neural netwOrk spontaneous combustion of coal oxygen concentration temperature prediction

NIR-Ⅱ responsive Janus nanoparticles amplify immunogenic cell death for enhanced cancer immunotherapy

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Science China(Technological Sciences) 2024年第1期67卷 321-329页

作者： CHEN BeiBei guo KangLi WANG HaoRan xu Fu-jian WANG JuLin ZHAO NaNa State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Key Laboratory of Biomedical Materials of Natural Macromolecules(Beijing University of Chemical Technology) Beijing Laboratory of Biomedical MaterialsBeijing University of Chemical TechnologyBeijing 100029China College of Materials Sciences and Engineering Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing University of Chemical TechnologyBeijing 100029China

Immunotherapy brings new hope for tumor treatment by inducing immunogenic cell death(ICD)of tumor ***,insufficient immunogenicity and low immune response rate greatly limit antitumor ***,by optimizing the composition and morphology,the rational design of Janus nanoparticles composed of Fe_(3)O_(4) nanospheres and SiO_(2)nanorods was realized for enhanced cancer immunotherapy through amplified *** glucose oxidase(GOx)was loaded by the Janus nanoparticles,the resultant M-FS-GOx consumes glucose at tumor sites to generate gluconic acid and hydrogen peroxide(H_(2)O_(2))for starvation therapy while the H_(2)O_(2)supply promotes the production of highly toxic·OH to achieve effective chemodynamic therapy(CDT).Under a 1064 nm light irradiation,the photothermal effect of M-FS-GOx enhances the enzyme activity of GOx for improved starvation ***,both tumor-associated antigens released during the process of ICD and the intrinsic immunoadjuvant property of M-FS-GOx stimulate dendritic cell maturation to activate antitumor immune *** work provides a promising strategy for the construction of Janus nanoparticles to achieve enhanced cancer immunotherapy through combination therapy-amplified ICD.

关键词： Janus nanoparticles immunogenic cell death cancer immunotherapy