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Rationale and design of Patient-centered Retrospective Observation of Guideline-Recommended Execution for Stroke Sufferers in China: China PROGRESS

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Stroke & Vascular Neurology 2019年第3期4卷 165-170页

作者： Zixiao Li Chunjuan Wang Yong Jiang Xinmiao Zhang Ying Xian Liping Liu Xingquan Zhao Hongqiu Gu Xia Meng Hao Li Yilong Wang Yongjun Wang Vascular Neurology Department of NeurologyBeijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina Center of Stroke Beijing Institute for BrainDisordersBeijingChina beijing Key Laboratory of Translational Medicine forCerebrovascular Disease BeijingChina Duke Clinical Research Institute North CarolinaUSA Neuro-intensive Care Unit Department of NeurologyBeijing Tiantan HospitalCapital Medical UniversityBeijingChina

Background In 2009,China launched ambitious healthcare reform plans to provide affordable and equitable basic healthcare for all patients,including the substantial number of patients who had a ***,little is known about the pattern of evidence-based stroke care and outcomes across hospitals,regions and time during the last *** The Patient-centered Retrospective Observation of Guideline-Recommended Execution for Stroke Sufferers in China(China PROGRESS)Study aims to use findings from a representative sample of Chinese hospitals over the last decade to improve future stroke care for patients hospitalised with ischaemic stroke(IS)or transient ischaemic attack(TIA).Design The China PROGRESS Study will use a two-stage cluster sampling method to identify over 32000 patient records from 208 hospitals across the Eastern,Central and Western geographical regions in *** assess the temporal trends in patient characteristics,treatment and outcomes,study investigators will select records from 2005,2010 and 2015.A double data reading/entry system will be developed to conduct this assessment.A central coordinating centre will monitor case ascertainment,data abstraction and data *** will examine patient characteristics,testing patterns,in-hospital treatment and outcomes,and variations across regions and across *** The China PROGRESS Study is the first nationally representative study that aims to better understand care quality and outcomes for patients with IS or TIA before and after the national healthcare reform in *** initiative will translate findings into clinical practices that improve care quality for patients who had a stroke and policy recommendations that allow these changes to be implemented *** approval This study has also been approved by the central institutional review board(IRB)at beijing Tiantan Hospital.

关键词： PROGRESS Observation centered

Frequency Veering of Rotating Metal Porous Twisted Plate with Cantilever Boundary Using Shell Theory

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Acta Mechanica Solida Sinica 2022年第2期35卷 282-302页

作者： Y.Y.Liu Y.X.Hao W.Zhang L.T.Liu S.W.Yang Y.T.Cao College of Mechanical Engineering Beijing Information Science and Technology UniversityBeijing 100192China College of Mechanical Engineering Beijing University of TechnologyBeijing 100124China

The frequency veering of a metal porous rotating cantilever twisted plate with twist angle and stagger angle is *** porous materials may have the characteristics of gradient or uniform distribution along the thickness *** on the classical shell theory,considering the influence of centrifugal force produced by high-speed rotation,the free vibration equations of a rotating cantilever twisted plate are *** the polynomial function and Rayleigh-Ritz method,the natural frequencies and mode shapes of the metal porous cantilever twisted plate in both static and rotating states are *** accuracy of the present theory and calculation results is confirmed by a comparison between them and the results available from the literature and those obtained from *** influences of the thickness ratio,porosity,twist angle,stagger angle and rotational velocity on the frequency veering and mode shape shift of the rotating cantilever twisted plate with porous material under three different distributions are *** should be mentioned that the frequency veering accompanied by mode shape shift occurs in both static and dynamic states.

关键词： Frequency veering Rotating twisted plate Cantilever boundary Metal porous

Design and characteristics of a non-contact rotational sensor based on a fiber Bragg grating

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Optoelectronics Letters 2016年第6期12卷 421-425页

作者：鹿利单李红姚齐峰何巍祝连庆 beijing Key Laboratory for Optoelectronics Measurement technology Beijing Engineering Research Center of Optoelectronic Information and Instruments Beijing Information Science and Technology University beijing Laboratory for Biomedical Detection technology and Instrument Beijing Information Science and Technology University

We propose a novel non-contact rotational sensor based on a fiber Bragg grating(FBG) packaged in a core of a magnetic head, which converts the introduced strain from the circular magnetic railings ruler into the rotational information. A mathematical model is built for processing the data obtained by an interrogator, and the accuracy and resolution of the measurements are analyzed by altering the radius and period of the circular magnetic railings ruler, as well as the dimension of the sensor. The experimental results show that it is in good accordance with the theoretical analysis on rotational angle, and the fitting results indicate that the results obtained from the rotational sensor match very well with the real rotational velocity with a linearity of 0.998 and a standard error of about 0.01.

关键词： rotational grating Bragg fitting match accordance circular permanent linearity magnet

Spatio-temporally resolved measurement of quantal exocytosis from single cells using microelectrode array modified with poly L-lysine and poly dopamine

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Chinese Chemical Letters 2016年第5期27卷 738-744页

作者： Li Wang Sheng-Wei Xu Hui-Ren Xu Yi-Lin Song Jun-Tao Liu Jin-Ping Luo Xin-Xia Cai State Key Laboratory of Transducer technology Institute of Electronics Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of sciences Beijing 100190 China

The subsecond, temporal, vesicular exocytosis is ubiquitous, but difficult detecting in communication mechanisms of cells. A microelectrode array （MEA）, fabricated by MEMS technology, was applied successfully for real-time monitoring of quantal exocytosis from single pheochromocytoma （PC12） cell, The developed MEA was evaluated by dopamine （DA） using electrochemical methods and the results revealed that the sensitivity of DA was improved to 12659.24 p.A L mmol 1 cm 2. The modified MEA was used to detect in vitro vesicular exocytosis of DA from single PCI 2 cells stimulated by concentrated 100 mmol L-1 K＋ cell solution. A total of 592 spikes were measured and analyzed by three parameters and the statistical results revealed the population of each parameter was an approximate Gaussian distribution, and on average, 1.31 × 106 ± 9.25× 104 oxidizable molecules were released in each quantal exocytosis. In addition, results also indicate that a single PC12 cell probably releases the spikes with T ranging from 25.6 ms to 35.4 ms corresponding to/max ranging from 45.6 pA to 65.2 pA. The devices, including a homemade computer interface and the MEA modified with polymer film, provides a new means for further research on the neural, intercellular, communication mechanism.

关键词： Microelectrode array Quantal exocytosis Dopamine Parameter

Elevation Influence on Rainfall and a Parameterization Algorithm in the beijing Area

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Journal of Meteorological Research 2019年第6期33卷 1143-1156页

作者： Linye SONG Mingxuan CHEN Feng GAO Conglan CHENG Min CHEN Lu YANG Yong WANG Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China Central Institute for Meteorology and Geodynamics Vienna A-1190Austria

Using a high-density automatic weather stations(AWS)dataset of hourly rainfall observations,the present study investigates the relationship between rainfall and elevation in the beijing area,and further proposes a rainfall amount dependent parameterized algorithm considering the elevation effect on rainfall on hourly *** parameterization equation is defined as a segmented nonlinear model,which calculates the mountain rainfall as a function of valley rainfall *** show that there exists an evident enhancement of rainfall amount by elevation effect in the beijing *** particular,larger rainfall amount is generally found in higher mountains,especially for slight rain and moderate ***,six representative station pairs located in valleys and on mountains respectively are selected to estimate the values of optimal parameters in the parameterization *** parameterization algorithm of elevation dependence can produce a reduction in the root-mean-square error and obtain a much closer mountain rainfall total to the observations compared with those using no elevation ***,the spatial distribution of rainfall is more realistic and accurate in mountainous terrain when elevation dependence is *** study helps to understand the variability of rainfall with complex terrain in the beijing area,and gives a possible way to parameterize rainfall–elevation relationship on hourly timescale.

关键词： rainfall elevation influence parameterization algorithm beijing

Thermoelectric transport properties of Pb-Sn-Te-Se system

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Rare Metals 2018年第4期37卷 343-350页

作者： Bing-Chao Qin Yu Xiao Yi-Ming Zhou Li-Dong Zhao School of Materials science and Engineering Beihang University Beijing 100191 China

IV-VI compounds are considered as promising thermoelectric materials, and high thermoelectric performance was achieved in IV-VI solid solutions. In this work, the thermoelectric properties of Pb-Sn-Te-Se-based solid solutions were systematically investigated. Among these solid solutions, it is found that a figure of merit （ZT） peak value of 1.0 at 873 K can be obtained in （PbTe）0.5（SnTe）o.5, on account of the combination of superior electrical properties in SnTe and low thermal conductivity in PbTe. Furthermore, we investigated and summarized the thermoelectric transport properties and proposed the thermoelectric performance maps for the IV- VI solid solutions in Pb-Sn-Te-Se system. This comprehensive investigation on Pb-Sn-Te-Se-based solid solutions can effectively guide and scan thermoelectric performance for a given unknown composition and enhance the thermoelectric properties in IV-VI compounds.

关键词： Thermoelectric materials Electricalconductivity Thermal conductivity Pb-Sn-Te-Se system Solid solutions

Collision Avoidance Strategy Supported by LTE-V-Based Vehicle Automation and Communication Systems for Car Following

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Tsinghua science and technology 2020年第1期25卷 127-139页

作者： Jiayang Li Yi Zhang Mengkai Shi Qi Liu Yi Chen Department of Mathematics Tsinghua UniversityBeijing 100084China beijing National Research Center for Information science and technology(BNRist) Department of AutomationTsinghua UniversityBeijing 100084China Tsinghua-Berkeley Shenzhen Institute(TBSI) Shenzhen 518055China Jiangsu Province Collaborative Innovation Center of Modern Urban Traffic Technologies Nanjing 210096China beijing Nebula Link Tech.Co.Ltd Beijing 100080China Network technology Research Institute China UnicomBeijing 100044China

We analyzed and improved a collision avoidance strategy, which was supported by Long Term EvolutionVehicle(LTE-V)-based Vehicle-to-Vehicle(V2 V) communication, for automated vehicles. This work was completed in two steps. In the first step, we analyzed the probability distribution of message transmission time, which was conditional on transmission distance and vehicle density. Our analysis revealed that transmission time exhibited a near-linear increase with distance and density. We also quantified the trade-off between high/low resource reselection probabilities to improve the setting of media access parameters. In the second step, we studied the required safety distance in accordance with the response time, i.e., the transmission time, derived on the basis of a novel concept of Responsibility-Sensitive Safety(RSS). We improved the strategy by considering the uncertainty of response time and its dependence on vehicle distance and density. We performed theoretical analysis and numerical testing to illustrate the effectiveness of the improved robust RSS strategy. Our results enhance the practicability of building driverless highways with special lanes reserved for the exclusive use of LTE-V vehicles.

关键词： vehicle automation and communication collision avoidance Long Term Evolution-Vehicle(LTE-V) Responsibility-Sensitive Safety(RSS)

Development of an innovative one-step nested PCR strategy for virus detection using the LNA technique

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science China(Life sciences) 2019年第3期62卷 428-430页

作者： Ji Wang Li Zhao Zhihua Sun Guixia Li Peihua Niu DANDi Li Lianjun Wang Yi Zhang Zhishan Feng Xuejun Ma National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention Hebei Medical University beijing Chaoyang Maternal & Child Health Hospital Children's Hospital of Hebei Province Dongcheng Center for Disease Control and Prevention Beijing

Dear Editor,Polymerase chain reaction(PCR)is a molecular diagnostic technique that has been widely used for diagnosing viral *** PCR(N-PCR)is a variation on the standard PCR technique that involves two amplification steps,yielding greater sensitivity and *** there are two main disadvantages:the protocol is more complex than conventional PCR,and the risk of cross-contamination is relatively ***-step nested PCR(OSN-PCR)enables conventional N-PCR to be performed as a closed reaction in a single tube that contains both outer and inner *** strategy makes OSN-PCR more rapid than N-PCR,lowers the probability of cross-contamination,and requires a smaller amount of reagents.

关键词： Dear Editor PCR strategy LNA technique

Physico-chemical characterization and source tracking of black carbon at a suburban site in beijing

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Journal of Environmental sciences 2015年第7期27卷 188-194页

作者： Hailin Wang Lei Nie Dan Liu Meiping Gao Minyan Wang Zhengping Hao National Urban Environmental Pollution Control Engineering Techniques Research Center Beijing Municipal Research Institute of Environmental Protection Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Nan-jing University of Information Science and Technology Department of Chemical Engineering School of Chemical & Environmental Engineering China University of Mining & Technology Department of Environmental Nano-materials Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Particles from ambient air and combustion sources including vehicle emission, coal combustion and biomass burning were collected and chemically pretreated with the purpose of obtaining isolated BC（black carbon） samples. TEM（transmission electron microscopy）results indicate that BC from combustion sources shows various patterns, and airborne BC appears spherical and about 50 nm in diameter with a homogeneous surface and turbostratic structure. The BET（Barrett-Emmett-Teller） results suggest that the surface areas of these BC particles fall in the range of 3-23 m2/g, with a total pore volume of 0.03-0.05 cm3/g and a mean pore diameter of 7-53 nm. The nitrogen adsorption-desorption isotherms are indicative of the accumulation mode and uniform pore size. O2-TPO（temperature programmed oxidation）profiles suggest that the airborne BC oxidation could be classified as the oxidation of amorphous carbon, which falls in the range of 406-490℃ with peaks at 418, 423 and 475℃,respectively. Generally, the BC characteristics and source analysis suggest that airborne BC most likely comes from diesel vehicle emission at this site.

关键词： Black carbon Characterization Source emission beijing