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The changes of intraoperative body temperature in adult liver transplantation: A retrospective study

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Hepatobiliary & Pancreatic Diseases International 2018年第6期17卷 496-501页

作者： Ying Sun li-li Jia Wen-li yu hong-li yu Ming-Wei Sheng hong-Yin Du Department of Anesthesiology Tianjin First Center Hospital

Background: Body temperature is poorly regulated in patients with end-stage liver disease. Due to the prolonged surgery time and anhepatic time as well as the complex surgical procedures performed in liver transplantation, the body temperature fluctuates greatly. This study investigated the effect of intraoperative body temperature fluctuations on the prognosis of liver recipients. Methods: The body temperatures of liver recipients recorded from the induction of anesthesia(T 0) until the end of surgery(T 14) were retrieved. The patients were divided into two groups: the hypothermia group( liver transplantation( P < 0.05). Hypothermia time was positively correlated with bleeding volume, intubation time, units of blood transfusions and intensive care stay, but negatively correlated with urine output. Conclusions: The intraoperative body temperature exhibited a graphical "V" trend, and the lowest temperature was at 5 min after reperfusion. The longer the duration of hypothermia, the more unfavourable the prognosis.

关键词： liver transplantation Temperature Hypothermia Ischemia reperfusion

Reliability evaluation of wireless sensor networks using an enhanced OBDD algorithm

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 62-70页

作者： XIAO yu-feng CHEN Shan-zhi li Xin li yu-hong State Key Laboratory of Networking and Switching Beijing University of Posts and Telecommunications Beijing 100876 China State Key Laboratory of Wireless Mobile Communication China Academy of Telecommunications Technology Beijing 100083 China Information Engineering School Southwest University of Science and Technology Mianyang 621000 China

An enhanced ordered binary decision diagram （EOBDD） algorithm is proposed to evaluate the reliability of wireless sensor networks （WSNs）, based on the considerations of the common cause failure （CCF） and a large number of nodes in WSNs. The EOBDD algorithm analyzes the common cause event （CCE） and the network structure when CCE takes place according to the stochastic graph and the CCF model of WSNs. After constructing the ordered binary decision diagram （OBDD） of the original network with node expansion, it uses a set of OBDD variables （SOV） to guide reliability computations along this OBDD. The two steps about OBDD can decrease the cost of OBDD constructions and storage. Furthermore, the efficient OBDD structure and Hash tables can greatly decrease redundant computations of isomorphs. The experiment results show that the EOBDD can be used to evaluate the reliability of WSN efficiently.

关键词： network reliability ordered binary decision diagram wireless sensor networks common cause failure common cause event

高效液相色谱法同时测定镥[^(177)Lu]氧奥曲肽注射液中两种稳定剂的含量

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核化学与放射化学 2025年第1期47卷 86-92,I0004页

作者：王勇梁塑孔祥瑞李英范振亚罗田伟王宁付博马红利杨柳李洪玉原子高科股份有限公司北京102413 国家原子能机构核技术(放射性药物工程转化)研发中心北京102413 中国核工业集团有限公司放射性药物工程技术研究中心北京102413

为建立高效液相色谱法(HPLC)测定镥[^(177)Lu]氧奥曲肽注射液中稳定剂(龙胆酸、维生素C)的含量,采用十八烷基硅烷键合有机杂化硅胶填充的色谱柱(4.6 mm×250 mm×5μm),以0.82 g/L醋酸钠溶液(用冰醋酸调pH至3.50)和甲醇为流动相,串联紫... 详细信息

为建立高效液相色谱法(HPLC)测定镥[^(177)Lu]氧奥曲肽注射液中稳定剂(龙胆酸、维生素C)的含量,采用十八烷基硅烷键合有机杂化硅胶填充的色谱柱(4.6 mm×250 mm×5μm),以0.82 g/L醋酸钠溶液(用冰醋酸调pH至3.50)和甲醇为流动相,串联紫外-可见分光检测器(检测波长为295 nm)与放射性流量检测器,柱温为25℃,进样体积为5μL,运行20.0 min,1.00 mL/min进行梯度淋洗,可有效地将龙胆酸和维生素C分离。龙胆酸和维生素C分别在0~1.50 g/L和0~30.0 g/L质量浓度范围内线性关系良好,相关系数r分别为1.000和0.998;改变柱温、流速、流动相pH值等色谱条件时,样品溶液中维生素C和龙胆酸含量的相对标准偏差均满足≤2.0%的要求;龙胆酸的回收率满足90%~108%的要求,维生素C回收率满足92%~105%的要求。该方法简便、快速、灵敏、准确,可用于镥[^(177)Lu]氧奥曲肽注射液中龙胆酸和维生素C含量的准确测定,为该类药物的工艺过程优化提供了指导作用。

关键词：高效液相色谱法镥[^(177)Lu]氧奥曲肽注射液稳定剂龙胆酸维生素C 方法验证

Prediction of Gas Emission Based on Infor-mation Fusion and Chaotic Time Series

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Journal of China University of Mining and Technology 2006年第1期16卷 94-96页

作者： GAO li yu hong-zhen College of Information and ElectricaI Engineering China University of Mining ＆ Technolog Xuzhou Jiangsu 221008 China

In order to make more exact predictions of gas emissions, information fusion and chaos time series are com- bined to predict the amount of gas emission in pits. First, a multi-sensor information fusion frame is established. The frame includes a data level, a character level and a decision level. Functions at every level are interpreted in detail in this paper. Then, the process of information fusion for gas emission is introduced. On the basis of those data processed at the data and character levels, the chaos time series and neural network are combined to predict the amount of gas emission at the decision level. The weights of the neural network are gained by training not by manual setting, in order to avoid subjectivity introduced by human intervention. Finally, the experimental results were analyzed in Matlab 6.0 and prove that the method is more accurate in the prediction of the amount of gas emission than the traditional method.

关键词： gas emission information fusion chaos time series neural network

Temperature Effect on the Mechanical Behavior of Acrylic Polymers under Quasi-static and Dynamic Loading

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上海交通大学学报 2004年第z2期38卷 89-95页

作者： Tao Suo yulong li hong yu Fei Xu Zhongbin Tang Lei li School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China Beijing Institute of Aeronautical Materials Beijing100095China

In this paper, the mechanical behavior of acrylic polymers at elevated temperature was investigated. Four acrylic polymers were tested at high strain rate by using compression Hopkinson bar and at quasi-static strain rate by using an Instron servo hydraulic axial testing machine with the testing temperature from 218K to 393K. The results show that the mechanical property of acrylic polymers depends heavily on the testing temperature. The yield stress and Young's modulus were found to decrease with increasing temperature at low strain rate. At very low temperature, the materials display typical brittle fracture; however their plasticity improves remarkably at high temperatures. The predictions of the mechanical behavior including the effect of temperature and strain rate using a proposed theoretical model have a good agreement with experimental results.

关键词： acrylic polymer compression Hopkinson bar quasi-static dynamic fracture

Comparison of 1.5% lidocaine and 0.5% ropivacaine epidural anesthesia combined with propofol general anesthesia guided by bispectral index

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第6期8卷 428-434页

作者： XIANG Yan li yu-hong Department of Anesthesiology the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective： To compare the effects of epidural anesthesia with 1.5% lidocaine and 0.5% ropivacaine on propofol requirements, the time to loss of consciousness （LOC）, effect-site propofol concentrations, and the hemodynamic variables during induction of general anesthesia guided by bispectral index （BIS） were studied. Methods： Forty-five patients were divided into three groups to receive epidurally administered saline （Group S）, 1.5% （w/w） lidocaine （Group L）, or 0,5% （w/w） ropivacaine （Group R） Propofol infusion was started to produce blood concentration of 4 lag/ml. Once the BIS value reached 40-50, endotracheal intubation was facilitated by 0.1 mg/kg vecuronium. Measurements included the time to LOC, effect-site propofol concentrations, total propofol dose, mean arterial blood pressure （MABP）, and heart rate （HR） at different study time points. Results： During induction of anesthesia, both Groups L and R were similar for the time to LOC, effect-site propofol concentrations, total propofol dose, MABP, HR, and BIS. The total doses of propofol administered until 1 min post-intubation were significantly less in patients of Groups R and L compared with Group S. MABP and HR were significantly lower following propofol induction compared with baseline values in the three groups, or MABP was significantly increased following intubation as compared with that prior to intubation in Group S but not in Groups R and L while HR was significantly increased following intubation in the three groups. Conclusion： Epidural anesthesia with 1.5% lidocaine and 0.5% ropivacaine has similar effects on the time to LOC, effect-site propofol concentrations, total propofol dose, and the hemodynamic variables during induction of general anesthesia.

关键词： Propofol lidocaine Ropivacaine Epidural anethesia Bispectral index

吉林西部生态系统服务时空变化特征及其驱动因素

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生态学杂志 2025年第1期44卷 240-249页

作者：李育虹王文娟费龙苏日古嘎孙鸿超张锦巴圣杰长春师范大学地理科学学院长春130032 中国科学院东北地理与农业生态研究所长春130102 长春理工大学化学与环境工程学院长春130022

近年来,气候变化和人类干扰活动导致生态系统服务退化,严重限制区域可持续性发展。科学认知生态系统服务变化特征及其驱动机制是制定区域可持续发展和提升生态安全保障政策的基础和前提。本研究以吉林西部为研究区,运用InVEST(Integrate... 详细信息

近年来,气候变化和人类干扰活动导致生态系统服务退化,严重限制区域可持续性发展。科学认知生态系统服务变化特征及其驱动机制是制定区域可持续发展和提升生态安全保障政策的基础和前提。本研究以吉林西部为研究区,运用InVEST(Integrated Valuation of Ecosystem Services and Tradeoffs Tools)模型定量评估了近10年(2010-2020年)吉林西部生态系统服务(产水量、土壤保持和生境质量),分析其时空变化特征,并揭示气候变化和土地利用/覆盖变化(LUCC)及其交互作用对生态系统服务变化的相对影响。结果表明:近10年,(1)在土地管理政策的驱动下,旱地、湿地和未利用地的面积减少,而水田、林地、草地和建设用地的面积呈增长趋势,其中减少的旱地主要转化为水田或林地。(2)近10年吉林西部生态系统服务总体呈增长趋势,且存在显著空间异质性;产水量和土壤保持量分别增加24.2%、51.6%,产水量增幅主要分布于中部和西北部的湿地和水田,土壤保持量增加区域主要位于西部和东北部的湿地和草地,而生境质量总体呈现下降趋势(-4.8%)。(3)近10年,产水量增加主要受气候变化(温度升高、降水增加)的正向影响,土壤保持量增加主要受气候变化及其与LUCC(植被覆盖增加)交互作用的影响,生境质量的下降主要由耕地面积增加和城市扩张等LUCC的负向影响。本研究结果可为吉林西部生态系统服务提升及资源合理利用与配置提供科学依据。

关键词：生态系统服务土地利用/覆盖变化气候变化 InVEST

Performance analysis of a rate adaptive multi-band ultra-wideband system based on quadrature fractal modulation scheme

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通信学报 2005年第10期26卷 34-40页

作者： li yu-hong ZHOU Zheng Wireless Network Lab Beijing University of Posts and Telecommunications Beijing 100876 China

A rate adaptive multi-band ultra-wideband (UWB) system based on the quadrature fractal modulation (QFM) scheme was *** the use of homogeneous signals as modulating waveforms in UWB system,the signal within each 528MHz sub-band was divided into 8 different frequency bandwidths using wavelets transform and these data sequences to be transmitted were embedded into homogeneous *** is found that the use of homogeneous signals in such UWB system is quite feasible,leadings to a novel multi-rate diversity *** each 528MHz sub-band,the UWB-QFM system can provide much higher data rates than that of the UWB orthogonal frequency division multiplexing (OFDM) *** results also show that the bit error rate (BER) performance of the UWB-QFM system achieves a greatly improvement over existing UWB-OFDM *** to the fractal properties of the homogeneous signals,these data sequences to be transmitted can be recovered using arbitrarily short receiver signal.

关键词：多频率传输积分调制微波传输直角频率分割多路技术

Coarsening and Age Hardening Behaviors of γ' Particles in GH742 During High Temperature Treatment

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Journal of Iron and Steel Research International 2009年第5期16卷 81-86页

作者： li hong-yu SONG Xi-ping WANG Yan-li CHEN Guo-liang State Key Lab for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

The coarsening and ageing hardening behaviors of γ′ particles in superalloy GH742 have been investigated by field emission scanning electron microscopy （FESEM）, coarsening kinetics calculation and microhardness testing when ageing at 1 050, 950 and 900 ℃ for different time. The cube of γ′ particle size and ageing time follows a linear law as predicted by LSW theory. The particle size distributions give better fit to the LSW theoretical distribution. The activation energy for γ′ coarsening is accurately determined to have 245. 06±14.42 kJ/mol when considering the effect of temperature on the solution concentrations in matrix. Based on the activation energy, the coarsening kinetics of γ′ particle is predicted as r^-t^3=7.35×10^15 Ce/T exp -（245060±14420）/RT *** microhardness studies indicate that microhardness decreases rapidly with increasing the ageing temperature and it has a maximum value corresponding to a critical particle size beyond which the microhardness increase stalls with increasing the ageing time.

关键词： superalloy γ′ particle coarsening kinetics activation energy microhardness