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4种肥胖测量指标与高脂血症关系的比较研究及适宜切点的选择

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复旦学报（医学版） 2015年第3期42卷 332-337,378页

作者：王琨李淑元金力王笑峰复旦大学生命科学学院现代人类学教育部重点实验室上海200433 复旦大学泰州健康科学研究院泰州225300

目的比较腰围（waist circumference,WC）、腰臀比（waist hip ratio,WHR）、腰围身高比（waist-to-height ratio,WHtR）、体质指数（body mass index,BMI）4种肥胖测量指标对高脂血症的风险效应,并选择最佳指标计算适宜切点,作为人群... 详细信息

目的比较腰围（waist circumference,WC）、腰臀比（waist hip ratio,WHR）、腰围身高比（waist-to-height ratio,WHtR）、体质指数（body mass index,BMI）4种肥胖测量指标对高脂血症的风险效应,并选择最佳指标计算适宜切点,作为人群高脂血症防控的简便目标.方法样本数据为泰州人口健康队列Ⅲ期基线调查,应用Pearson相关、Logistic回归来分析4种指标之间及其与血清胆固醇升高（高TC）、三酰甘油升高（高TG）、低密度脂蛋白升高（高LDL）和高密度脂蛋白降低（低HDL）的关联.选择风险贡献最大的指标,计算防控适宜切点及人群归因危险度（population attributable risk,PAR）.结果相关系数矩阵显示,WHtR与各代谢指标的综合相关性最高;调整常见混杂因素后的Logistic回归分析显示,WHtR对高TC、高LDL及低HDL的风险均相对最高,OR （95 ％CI）分别为1.34 （1.28～1.35）、1.42 （1.37～1.48）及1.45 （1.30～1.54）.而对于高TG,风险最高的指标为WC,调整常见混杂因素后OR（95％CI）为2.09 （1.97～2.22）,其余依次为WHtR的1.97 （1.86～2.09）,WHR的1.93 （1.82～2.05）和BMI的1.80 （1.75～1.86）.可见WHtR对高脂血症有最大的风险效应.性别和年龄分层后,4种指标的风险排序不变.以WHtR作为预测高脂血症的指标选择最优切点,范围为0.51～0.53.以0.52为防控目标计算人群PAR％,可防止人群中约27％的高TG、23％的高TC、近30％的高LDL和16％的低HDL-C的发生.结论在反映高脂血症的肥胖测量指标中,WHtR具有最大的风险效应.可将WHtR＜0.52作为预防高脂血症的简易防控目标,发挥其在健康教育与自我管理中的作用.

关键词：高脂血症腰围腰臀比腰围身高比体质指数最优切点

Two new steroidal saponins from the rhizomes of Dioscorea zingiberensis

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Chinese Journal of Natural Medicines 2014年第2期12卷 142-147页

作者： ZHENG Lu ZHOU yuan ZHANG Jia-Yu SONG Min yuan Ye xiao Yan-Jiao XIANG Ting Research Institute of Traditional Chinese Medicine Yangtze River Pharmaceutical Group Co. Ltd. School of Chinese Pharmacy Beijing University of Chinese Medicine

AIM: To investigate the chemical constituents of Dioscorea zingiberensis C. H. Wright. METHODS: The compounds were isolated by various chromatographic techniques, and the structures of the new steroidal saponins were elucidated by extensive 1D- and 2D-NMR, MS, and IR spectral analysis. RESULTS: The 70% EtOH extract of the rhizomes of Dioscorea zingiberensis afforded two new steroidal saponins, zingiberenosides A(1) and B(2), along with eight known analogues, 3β, 26-dihydroxy-25(R)-furosta-△5, 20(22)-diene-3-O-α-Lrhamnopyranosyl-(1→2)-O-β-D-glucopyranoside(3), methyl parvifloside(4), deltoside(5), methyl deltoside(6), zingiberensis new saponin(7), deltonin(8), progenin III(9) and diosgenin-diglucoside(10). CONCLUSION: Two new steroidal saponins were isolated from Dioscorea zingiberensis and their structures determined.

关键词： Dioscorea zingiberensis Dioscoreaceae Steroidal saponins Zingiberenoside

Planning Method and Coordinated Operation Strategy for Multi-station Integration System

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 2394-2408页

作者： Ankang Miao Yue yuan Han Wu Junpeng Zhu the College of Energy and Electrical Engineering Hohai UniversityNanjing 211100China

A multi-station integration system(MSIS)integrat-ing other multi-type stations provides a new way to realize an intensive development of resources and promote low-carbon en-ergy and its high-efficiency *** this end,a novel multi-station integration planning method and coordinated operation strategy model for the MSIS are established in a new business *** this study,a new business model of the MSIS,with substations as the carrier,integrating distributed photovoltaic,energy storage,electric vehicle charging,data center,and 5G base stations is *** the social environment,natural conditions,and complementary characteristics,a comprehensive index system is established to analyze expansion capability of substations and multi-station combination *** reduction is performed by extracting feature vectors and build-ing a comprehensive evaluation function to select the optimal combination scheme under a specific ***,for the combination scheme in a specific scenario,the optimal ca-pacity configuration and coordinated operation strategy chance-constrained programming model of the MSIS are established under different operating ***,simulations are performed on a practical MSIS located in Wuxi,China,and simulation results demonstrate the rationality and effectiveness of the planning method and coordinated operation strategy model for the MSIS.

关键词： Business model comprehensive index system coordinated operation strategy multi-station combination scheme multi-station integration system planning method

Corrosion–wear behavior of a biocompatible magnesium matrix composite in simulated body fluid

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Friction 2022年第1期10卷 31-43页

作者： Jinlong SU Jie TENG Zili XU yuan LI College of Materials Science and Engineering Hunan UniversityChangsha 410082China The First Affiliated Hospital Hunan Normal UniversityChangsha 410006China

Magnesium matrix composites are a new generation of biocompatible implant materials,but they will inevitably undergo simultaneous wear and corrosion in the human *** this study,hydroxyapatite(Ca10(PO4)6(OH)2,HA)is used in a magnesium matrix composite to study its effects on the corrosion–wear *** samples(a magnesium alloy composed of Mg,Zn,and Zr(ZK60)alloy and ZK60/10HA composite)were fabricated using the powder metallurgy(PM)*** corrosion–wear behavior was investigated using the sliding wear test in a simulated body fluid(SBF).At all the sliding velocities tested,the corrosion–wear resistance of ZK60/10HA was superior to *** a sliding velocity of 942.5 mm/min,ZK60/10HA demonstrated a 42%improvement in corrosion–wear resistance compared to *** ZK60,the main wear mechanism under dry conditions was abrasion,while the wear mechanisms in the SBF were abrasion and *** ZK60/10HA,the wear mechanisms under dry conditions were abrasion and delamination,while in SBF they were mainly abrasion and corrosion,accompanied by slight *** results indicated that HA particles can be used as an effective corrosion–wear inhibitor in biocompatible magnesium matrix composites.

关键词： wear corrosion alloy

Numerical investigation of flow over a two-dimensional square cylinder with a synthetic jet generated by a bi-frequency signal

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Applied Mathematics and Mechanics(English Edition) 2022年第10期43卷 1569-1584页

作者： Yiran LU yuan QU Jiangsheng WANG Jinjun WANG Fluid Mechanics Key Laboratory of Education Ministry Beihang UniversityBeijing 100191China

The flow around a square cylinder with a synthetic jet positioned at the rear surface is numerically investigated with the unsteady Reynolds-averaged Navier-Stokes(URANS)*** of the typical sinusoidal wave,a bi-frequency signal is adopted to generate the synthetic *** bi-frequency signal consists of a basic sinusoidal wave and a high-frequency *** with various amplitudes of the high-frequency component are *** is found that synthetic jets actuated by bi-frequency signals can realize better drag reduction with lower energy consumption when appropriate parameter sets are applied.A new quantity,i.e.,the actuation efficiency Ae,is used to evaluate the controlling *** actuation efficiency Ae reaches its maximum of 0.2668 when the amplitude of the superposed high-frequency signal is 7.5%of the basic *** vortex structures and frequency characteristics are subsequently analyzed to investigate the mechanism of the optimization of the bi-frequency *** the synthetic jet is actuated by a single-frequency signal with a characteristic velocity of 0.112 m/s,the wake is *** alternative deflection of vortex pairs and the peak at half of the excitation frequency in the power spectral density(PSD)function are *** the bi-frequency cases with the same characteristic velocity,the wake gradually turns to be symmetrical with the increase in the amplitude of the high-frequency ***,the deflection of the vortex pairs and the peak at half of the excitation frequency gradually disappear as well.

关键词： synthetic jet flow control signal superposition vortex dynamics

LIDAR:learning from imperfect demonstrations with advantage rectification

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Frontiers of Computer Science 2022年第1期16卷 57-66页

作者： xiaoqin ZHANG Huimin MA Xiong LUO Jian yuan Department of EE Tsinghua UniversityBeijing100084China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China

In actor-critic reinforcement learning(RL)algorithms,function estimation errors are known to cause ineffective random exploration at the beginning of training,and lead to overestimated value estimates and suboptimal *** this paper,we address the problem by executing advantage rectification with imperfect demonstrations,thus reducing the function estimation *** with expert demonstrations has been widely adopted to accelerate the learning process of deep reinforcement learning when simulations are expensive to ***,existing methods,such as behavior cloning,often assume the demonstrations contain other information or labels with regard to performances,such as optimal assumption,which is usually incorrect and useless in the real *** this paper,we explicitly handle imperfect demonstrations within the actor-critic RL frameworks,and propose a new method called learning from imperfect demonstrations with advantage rectification(LIDAR).LIDAR utilizes a rectified loss function to merely learn from selective demonstrations,which is derived from a minimal assumption that the demonstrating policies have better performances than our current *** learns from contradictions caused by estimation errors,and in turn reduces estimation *** apply LIDAR to three popular actor-critic algorithms,DDPG,TD3 and SAC,and experiments show that our method can observably reduce the function estimation errors,effectively leverage demonstrations far from the optimal,and outperform state-of-the-art baselines consistently in all the scenarios.

关键词： learning from demonstrations actor-critic reinforcement learning advantage rectification

Low-cost all-iron flow battery with high performance towards long-duration energy storage

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Journal of Energy Chemistry 2022年第10期31卷 445-451,I0011页

作者： xiaoqi Liu Tianyu Li Zhizhang yuan Xianfeng Li Division of Energy Storage Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China

Long duration energy storage(LDES)technologies are vital for wide utilization of renewable energy sources and increasing the penetration of these technologies within energy ***,we propose a low-cost alkaline all-iron flow battery by coupling ferri/ferro-cyanide redox couple with ferric/ferrous-gluconate complexes redox *** designed all-iron flow battery demonstrates a coulombic efficiency of above 99%and an energy efficiency of~83%at a current density of80 m A cm^(-2),which can continuously run for more than 950 *** importantly,the battery demonstrates a coulombic efficiency of more than 99.0%and an energy efficiency of~83%for a long duration(~12,16 and 20 h per cycle)charge/discharge *** from the low cost of iron electrolytes,the overall cost of the all-iron flow battery system can be reached as low as$76.11 per k Wh based on a10 h system with a power of 9.9 k *** work provides a new option for next-generation cost-effective flow batteries for long duration large scale energy storage.

关键词： Long-duration energy storage All-iron flow battery Iron-based complexes High performance Gluconate

Numerical Analysis of Heat Transfer Characteristics to Supercritical CO_(2) in a Vertical Mini-Channel:Transition and Pseudo-Boiling

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Journal of Thermal Science 2024年第1期33卷 101-113页

作者： yuan Baoqiang WANG Wei XIN Gongming DU Wenjing School of Energy and Power Engineering Shandong UniversityJi'nan 250061China

Large eddy simulations have been conducted to study upward transitional flows and heat transfer characteristics of supercritical CO_(2) in a vertical *** numerical simulation was carried out on a modified buoyantPimpleFOAM solver in OpenFOAM 7,and was verified using experiment *** results indicate that increasing the Grashof numbers can reduce the flow stability and make the flow transition *** are four stages of heat transfer in the transition process,i.e.,weakened,improved,recovered and normal heat *** heat transfer phenomena in the transition process were explained from three perspectives:thermal boundary layer theory,turbulent transport and pseudo-boiling *** transfer enhancement during transition is related to the transport of supercritical molecular clusters,and these molecular clusters are regarded as pseudo-bubbles in pseudo-boiling *** flow pattern of the pseudo-phases in the dia-Widom process contains single-phase flow,steady pseudo-film flow,unsteady pseudo-film flow,partial pseudo-bubbles flow and flocculent pseudo-film ***-bubbles have similar behaviors to subcritical bubbles,i.e.,break-up,deformation,condensation and *** researches in this work are favorable for understanding the heat transfer mechanism of supercritical fluids during flow transition.

关键词： supercritical heat transfer large eddy simulation transition pseudo-boiling

Dynamic Simulation of a Novel Solar Polygeneration System for Heat, Power and Fresh Water Production based on Solar Thermal Power Tower Plant

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Journal of Thermal Science 2020年第2期29卷 378-392页

作者： LI Xing WANG Zhifeng YANG Ming yuan Guofeng Key Laboratory of Solar Thermal Energy and Photovoltaic System Chinese Academy of SciencesBeijing 100190China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Beijing Engineering Research Center of Solar Thermal Power Beijing 100190China

A novel solar polygeneration system for heat, power and fresh water production with absorption heat pump(AHP) and humidification-dehumidification(HDH) desalination system was proposed for high-efficiency utilization of solar energy. A case study of the proposed system was investigated based on 1 MW solar thermal power(STP) tower plant located in Beijing. Depending on mathematical modeling of the proposed system, corresponding modules were developed in TRNSYS. Meanwhile, control and operation strategies were fully studied with principal of solar energy cascade utilization. The thermodynamic performance of the proposed system was dynamically simulated at one minute intervals in a typical day. It was found that solar energy utilization level was improved with the help of solar thermal storage system and continuous heating in different operation modes met well with flexible heating loads from 93.76 kW to 169.49 kW. During AHP operation period, its Coefficient of Performance(COP) varied from 1.39 to 1.73 due to recoverable condensate heat restricted by heating demand. Meanwhile, fresh water production of HDH increased from 352.05 kg/h to 416.62 kg/h with Gained Output Ratio(GOR) increase from 2.48 to 2.67. Compared with original STP tower plant, maximum power generation efficiency was increased from 18.66% to 19.22% with power from 1169.69 kW to 1204.44 kW.

关键词： polygeneration solar thermal power dynamic simulation absorption heat pump humidification-dehumidification