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代谢综合征对冠心病血运重建患者预后的影响

中华糖尿病杂志 2010年第6期2卷 -页

作者：胡荣马长生吕强康俊萍聂绍平杜昕刘新民刘晓惠陈方周玉杰吕树铮首都医科大学附属北京安贞医院心内科 100029

目的探讨集中了5个心血管病危险因素(肥胖、糖代谢异常、高血压、高甘油三酯血症、低高密度脂蛋白胆固醇血症)的代谢综合征在冠心病患者中的流行趋势和预后意义.方法研究对象来自单中心注册研究DESIRE(drug-eluting stent impact on r... 详细信息

目的探讨集中了5个心血管病危险因素(肥胖、糖代谢异常、高血压、高甘油三酯血症、低高密度脂蛋白胆固醇血症)的代谢综合征在冠心病患者中的流行趋势和预后意义.方法研究对象来自单中心注册研究DESIRE(drug-eluting stent impact on revascularization),入选2003年7月1日至2004年9月30日在首都医科大学附属安贞医院接受血运重建治疗[经皮冠状动脉介入(PCI)或冠状动脉旁路移植术(CABG)]的2368例患者,选择其中身高、体重、血压、血糖和血脂等记录完整的患者共1911例,平均年龄(60±10)岁,记录其临床资料及随访期间临床不良事件,患者死亡为随访终止,记录死亡时间.代谢综合征定义采用2005年美国胆固醇教育计划成人治疗专家组修订(NCEP ATP Ⅲ)的定义,以体重指数(BMI)≥25 kg/m2代替腹围指标.计量资料均值应用-x±s表示,两组间比较采用t检验,多组间比较采用方差分析,计数资料采用x2检验,不良事件与代谢综合征患者的相关性应用Logistic和Cox回归分析.结果相应临床资料记录完整的患者1911例,其中男性1458例占76.3%.截至2007年底随访时间中位数为3.5年(293～1855 d).按照是否合并代谢综合征将患者分为2组,发现合并代谢综合征对住院期间和随访期间的死亡率没有影响,但明显增加随访期间主要不良心脑血管事件(MACCE)的发生率(P＜0.05).随访3.5年,合并代谢综合征患者增加的MACCE事件主要表现在:再次血运重建事件、脑卒中事件和再入院事件(P＜0.05);把性别、年龄、血脂等心血管危险因素放入Logistic模型中,比较影响总MACCE发生的危险因素,仅发现合并代谢综合征是影响总MACCE发生的惟一因素(OR 1.319,95%CI 1.020～1.706,P＜0.05).应用Logistic回归分析代谢综合征5个组成成分对随访MACCE的影响,发现糖代谢异常(OR 1.047,95% CI 1.005～1.091,P＜0.05)和低高密度脂蛋白胆固醇血症(OR 0.777,95%CI0.610～0.989,P＜0.05)是影响预后的主要因素.同时发现无论是否合并糖尿病,代谢综合征对3.5年随访MACCE事件均有显著的预测意义(合并糖尿病人群中:OR 1.516,95%CI1.062～2.159,P＜0.05;无糖尿病人群中:OR1.398,95%CI1.021～2.092,P＜0.05),只是比值比在未合并糖尿病的冠心病患者中略有降低.结论在冠心病血运重建患者中,代谢综合征可以预测冠心病患者的不良预后,无论是否合并糖尿病,代谢综合征对随访MACCE事件都有显著的预测意义.

关键词：代谢综合征冠心病预后

Synthesis of Various Types of Silver Nanoparticles Used as Physical Developing Nuclei in Photographic Science

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Chinese Chemical Letters 2003年第6期14卷 645-648页

作者： jun ping ZHANG Li Qi SHENG ping CHEN Technical Institute of Physics and Chemistry CASBeijing 100101

Ag nanoparticles used as physical developing nuclei in photographic science were prepared by reduction method. The as-formed Ag nanoparticle colloid was characterized by UV-Vis absorption spectrum, Atomic Force Microscopy(AFM) and Charge Coupled Device (CCD) technique. It is found that the source of Ag ions, the addition of surfactant and polymer, all have great influence on the size, topography and catalytic activity of Ag nanoparticles.

关键词： Ag nanoparticle AFM DTR.

Degradation of dyestuff wastewater using visible light in the presence of a novel nano TiO_2 catalyst doped with upconversion luminescence agent

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Journal of Environmental Sciences 2005年第5期17卷 727-730页

作者： WANG jun WEN Fu-yu ZHANG Zhao-hong ZHANG Xiang-dong PAN Zhi-jun ZHANG Lei WANG Lei XU Liang kang ping-li ZHANG Peng Department of Chemistry Liaoning University Shenyang 110036 China Department of Environment Liaoning University Shenyang 110036 China Center of Analysis and Test Liaoning University Shenyang 110036 China

A new upconversion luminescence agent, 40CdF2·60BaF2·0.8ErO3, was synthesized and its fluorescent spectra were determined. This upconversion luminescence agent can emit five upconversion fluorescent peaks shown in the fluorescent spectra whose wavelengths are all below 387 nm under the excitation of 488 nm visible light. This upconversion luminescence agent was mixed into nano rutile TiO2 powder by ultrasonic and boiling dispersion and the novel doped nano TiO2 photocatalyst utilizing visible light was firstly prepared. The doped TiO2 powder was charactered by XRD and TEM and its photocatalytic activity was tested through the photocatalytic degradation of methyl orange as a model compound under the visible light irradiation emitted by six three basic color lamps. In order to compare the photocatalytic activities, the same experiment was carried out for undoped TiO2 powder. The degradation ratio of methyl orange in the presence of doped nano TiO2 powder reached 32.5% under visible light irradiation at 20 h which was obviously higher than the corresponding 1.64% in the presence of undoped nano TiO2 powder, which indicate the upconversion luminescence agent prepared as dopant can effectively turn visible lights to ultraviolet lights that are absorbed by nano TiO2 particles to produce the electron-cavity pairs. All the results show that the nano rutile TiO2 powder doped with upconversion luminescence agent is a promising photocatalyst using sunlight for treating the industry dye wastewater in great force.

关键词： upconversion luminescence agent nano TiO2 photocatalytic degradation visible light methyl orange

Experimental and numerical simulation of air-water two-phase flow in the rod bundle with grid spacer

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Nuclear Science and Techniques 2004年第1期15卷 46-52页

作者： WANGXiao-jun CHENBing-De HUANGYan-ping NationalKeyLaboratoryofBubblePhysicsandNaturalCirculation P.O.Box622-205Chengdu610041

Experimental and numerical simulation were carried out on vertically upward air-water two-phase flow in the rod bundle with grid spacer. The related numerical simulation has been performed by using the Computational Fluid Dynamics code-CFX4.2, in which lateral interfacial effects based on a two-fluid model are accounted for. This model has been used to evaluate the velocity fields of gas and liquid phases, as well as phase distribution between elements in rod bundle by simulating 1/4 zone of experimental model, and mixing vanes of spacer in this area. Fur- thermore, this model has been used to predict the effects of spacer on flow and pressure drop along the rod bundle. The calculation results show that the mixing vane has significant influence on axial and lateral velocity. In order to obtain some experimental data to verify the numerical solutions, a series of tests, using a specially designed 3×3 rod bundle test section with AFA-2G structure spacer have been performed. An optical probe was used to measure local void fractions. At the same time, the pressure loss has been measured. A comparison between the calculated void pro- file and pressure loss and the measured results shows that the predicted void profiles are consistent at low gas appar- ent velocity. This research shows that the code CFX4.2 can be used to describe the 3-D air-water two-phase flow in the rod bundle channel with grid spacer.

关键词：数值模拟气液两相流盘条网分隔机流体动力学燃料组件

基于Unity3d的电气实验教学平台的设计与实现

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天津理工大学学报 2025年第1期41卷 104-111页

作者：康军张鹏李晓飞天津理工大学电气工程与自动化学院

针对传统电气实验教学中长期存在且尚未得到有效解决的问题，以电气专业知识为基础，以VR眼镜为设备载体，以Unity3d为开发平台，通过电气技术和虚拟现实技术的有效结合设计开发出一种基于Unity3d的电气实验教学平台。该平台使用Maya建... 详细信息

针对传统电气实验教学中长期存在且尚未得到有效解决的问题，以电气专业知识为基础，以VR眼镜为设备载体，以Unity3d为开发平台，通过电气技术和虚拟现实技术的有效结合设计开发出一种基于Unity3d的电气实验教学平台。该平台使用Maya建模软件进行三维建模，利用Unity3d中功能强大的系统和灵活的C#脚本语言编程实现人机交互效果，在此平台上开发的电动机运行实验，使学生不仅可以完成电动机接线、运行、过载等基础实验，还可以在保障用电安全的前提下进行任意操作，模拟电路短路、电机损坏等事故的发生，情景化感受事故后果。该电气实验教学平台的优势主要体现在低实验成本运行、高安全系数操作、创新教学模式和提升教学效率上，在学生提升相应工程技能的同时，不断创新电气实验教学模式，实现高质量教学产出。

关键词：虚拟现实 Unity3d 实验教学电气专业

Methods for seismic sedimentology research on continental basins

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Petroleum Science 2015年第1期12卷 67-80页

作者： ping-Sheng Wei Ming-jun Su Petrochina Research Institute of Petroleum Exploration & Development-Northwest

In contrast to marine deposits, continental deposits in China are characterized by diverse sedimentary types, rapid changes in sedimentary facies, complex lithology, and thin, small sand bodies. In seismic sedimentology studies on continental lacustrine basins, new thinking and more detailed and effective technical means are needed to generate lithological data cubes and conduct seismic geo- morphologic analyses. Based on a series of tests and studies, this paper presents the concepts of time-equivalent seismic attributes and seismic sedimentary bodies and a ＂four-step approach＂ for the seismic sedimentologic study of conti- nental basins： Step 1, build a time-equivalent stratigraphic framework based on vertical analysis and horizontal corre- lation of lithofacies, electrofacies, seismic facies, and pale- ontological combinations; Step 2, further build a sedimentary facies model based on the analysis of single- well facies with outcrop, coring, and lab test data; Step 3, convert the seismic data into a lithological data cube reflecting different lithologies by means of seismic tech- niques; and Step 4, perform a time-equivalent attribute analysis and convert the planar attribute into a sedimentary facies map under the guidance of the sedimentary facies model. The whole process, highlighting the verification and calibration of geological data, is an iteration and feedback procedure of geoseismic data. The key technologies include the following：（1） a seismic data-lithology conversion technique applicable to complex lithology, which can convert the seismic reflection from interface types to rock layers; and （2） time-equivalent seismic unit analysis and a time- equivalent seismic attribute extraction technique. Finally, this paper demonstrates the validity of the approach with an example from the Qikou Sag in the Bohai Bay Basin and subsequent drilling results.

关键词： Continental basin Seismic sedimentology Four-step approach Time-equivalent seismic attribute Seismic sedimentary body Lithology conversion processing

Simplified transmitter design for MIMO systems with channel uncertainty

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The Journal of China Universities of Posts and Telecommunications 2009年第2期16卷 20-23,34页

作者： DU Juan kang Gui-xia ZHANG ping Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China School of Information Science and Engineering Lanzhou University Lanzhou 730000 China

This article investigates transmitter design in Rayleigh fading multiple input multiple output （MIMO） channels with spatial correlation when there are channel uncertainties caused by a combined effect of channel estimation error and limited feedback. To overcome the high computational complexity of the optimal transmit power allocation, a simple and suboptimal allocation is proposed by exploiting the transmission constraint and differentiating a bound based on Jensen inequality on the channel capacity. The simulation results show that the mutual information corresponding to the proposed power allocation closely approaches the channel capacity corresponding to the optimal one and meanwhile the computational complexity is greatly reduced.

关键词： MIMO capacity channel state information (CSI) channel estimation error covariance feedback mutual information power allocation

NUMERICAL STUDY OF 3D EXPLOSION BUBBLES ADJACENT TO STRUCTURES

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Journal of Hydrodynamics 2002年第4期14卷 66-72页

作者： Li, Wan-ping Li, Liang-jun Dept. of Mech. Huazhong Univ. of Sci. and Technol. Wuhan 430074 China

The bejavior of a bubble near a rigid structure was considered by using the local surface fitting method and the jet prediction method. The convergence difficulty caused by the abnormality of the elements was overcome. The flow was numerically simulated by using the boundary-integral method on the assumption that the water was inviscid and incompressible, and the bubble gas obeyed the isentropic rule. The evolution of the bubble was investigated by means of the mixed Euler-Lagrange method, and the Runge-Kutta method. The important behavior of the bubble, such as migration and jetting, was analyzed in several examples. The solution of one period of the explosion bubble was obtained.

关键词： Bubbles (in fluids) Shock waves Structures (built objects)

A multiwavelength study of the star forming HⅡ region Sh2-82

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Research in Astronomy and Astrophysics 2012年第6期12卷 651-660页

作者： Nai-ping Yu jun-Jie Wang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China NAOC-TU Joint Center for Astrophysics Lhasa 850000 China

Based on a multiwavelength study, the interstellar medium and young stel- lar objects （YSOs） around the H II region Sh2-82 have been analyzed. Two molecular clumps were found from the archival data of the Galactic Ring Survey, and using the Two Micron All-Sky Survey catalog, we found two corresponding young clusters embedded in the molecular clumps. The very good relations between CO emission, infrared shells and YSOs suggest that it is probably a triggered star formation region from the expansion of Sh2-82. We further used the data from the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire from Spitzer to study the YSOs within the two clumps, confirming star formation in this region. By spectral energy distribution fits to each YSO candidate with infrared excess, we derived the slope of the initial mass function. Finally, comparing the H II region＇s dynamical age and the fragmenta- tion time of the molecular shell, we discard the ＂collect and collapse＂ process as being the triggering mechanism for YSO formation. Sh2-82 can be a mixture of other pro- cesses such as radiative-driven implosion and/or collisions with pre-existing clumps.

关键词： ISM: clouds -- nebulae: HII region -- individual: Sh2-82 -- stars:formation