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Optimal timing of staged percutaneous coronary intervention in ST-segment elevation myocardial infarction patients with multivessel disease

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Journal of Geriatric Cardiology 2018年第5期15卷 356-362页

作者： Xue-Dong ZHAO Guan-Qi ZHAO Xiao WANG Shu-Tian shi Wen ZHENG rui-Feng GUO shao-Ping NIE Beijing Anzhen Hospital Capital Medical University Beijing Institute of Heart Lung and Blood Vessel Diseases Beijing China

Background Studies have shown that staged percutaneous coronary intervention （PCI） for non-culprit lesions is beneficial for prog- nosis of ST-segment elevation myocardial infarction （STEMI） patients with multivessel disease. However, the optimal timing of staged re- vascularization is still controversial. This study aimed to find the optimal timing of staged revascularization. Methods A total of 428 STEMI patients with multivessel disease who underwent primary PCI and staged PCI were included. According to the time interval between primary and staged PCI, patients were divided into three groups （〈 1 week, 1- weeks, and 2-12 weeks after primary PCI）. The primary endpoint was major adverse cardiovascular events （MACE）, a composite of all-cause death, non-fatal re-infarction, repeat revascularization, and stroke. Cox regression model was used to assess the association between staged PCI timing and risk of MACE. Results During the follow-up, 119 participants had MACEs. There was statistical difference in MACE incidence among the three groups （〈 1 week： 23.0%; 1-2 weeks： 33.0%; 2-12 weeks： 40.0%; P = 0.001）. In the multivariable adjustment model, the timing interval of staged PCI ≤ 1 week and l-2 weeks were both significantly associated with a lower risk of MACE [hazard ratio （HR）： 0.40, 95% confidence intervals （CI）： 0.24-4）.65; HR： 0.54, 95% CI： 0.3 lq3.93, respectively], mainly attributed to a lower risk of repeat revascularization （HR： 0.41, 95% CI： 0.24-0.70; HR： 0.36, 95% CI： 0.18-0.7）, compared with a strategy of 2-12 weeks later of primary PCI. Conclusions The optimal timing of staged PCI for non-culprit vessels should be within two weeks after primary PCI for STEMI patients.

关键词： Myocardial infarction Multivessel disease Non-culprit lesion Percutaneous coronary intervention Timing

Effects of arbuscular mycorrhizal fungi inoculation on arsenic accumulation by tobacco (Nicotiana tabacum L.)

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Journal of Environmental Sciences 2009年第9期21卷 1214-1220页

作者： HUA Jianfeng LIN Xiangui YIN rui JIANG Qian shao Yufang State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China. Institute of Botany Jiangsu Province and the Chinese Academy of Sciences Nanjing 210014 China Soil and Environment Analysis Center Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Bioengineering College of lnner Mongolia Agricultural University Huhhot 010019 China

A pot experiment was conducted to study the effects of arbuscular mycorrhizal （AM） fungi （from contaminated or uncontaminated soils） on arsenic （As） uptake of tobacco （Nicotiana tabacurn L.） in As-contaminated soil. Mycorrhizal colonization rate, dry weight, As and P uptake by plants, concentrations of water-extractable As and As fractions were determined. A low mycorrhizal colonization rate （〈 25%） was detected. Our research indicated that AM fungi isolated from polluted soils were no more effective than those from unpolluted soils when grown in symbiosis with tobacco. No significant differences were observed in roots and stalks dry weights among all treatments. Leaves and total plant dry weights were much higher in Glomus versiforme treatment than that in control treatment. As contents in roots and stalks from mycorrhizal treatments were much lower than that from control treatment. Total plant As content exhibited the same trend. P concentrations in tobacco were not affected by colonization, nor were stalks, leaves and total plant P contents. Roots P contents were remarkably lower in HN treatments than in other treatments. Meanwhile, decreased soil pH and lower water-extractable As concentrations and higher levels of As fraction bound to well-crystallized hydrous oxides of Fe and AI were found in mycorrhizal treatments than in controls. The protective effect of mycorrhiza against plant As uptake may be associated with changes in As solubility mediated by changing soil pH. These results indicated that under As stress, proper mechanisms employed by AM fungi can protect tobacco against As uptake. Results confirmed that AM fungi can play an important role in food quality and safety.

关键词： arbuscular mycorrhizal fungi arsenic tobacco soil pH

Influence of construction interfaces on dynamic characteristics of roller compacted concrete dams

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Journal of Central South University 2015年第4期22卷 1521-1535页

作者： GU Chong-shi WANG shao-wei BAO Teng-fei State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University College of Water-Conservancy and Hydropower Hohai University

To study the influence of construction interfaces on dynamic characteristics of roller compacted concrete dams(RCCDs),mechanical properties of construction interfaces are firstly analyzed. Then, the viscous-spring artificial boundary(VSAB) is adopted to simulate the radiation damping of their infinite foundations, and based on the Marc software, a simplified seismic motion input method is presented by the equivalent nodal loads. Finally, based on the practical engineering of a RCC gravity dam, effects of radiation damping and construction interfaces on the dynamic characteristics of dams are investigated in detail. Analysis results show that dynamic response of the RCC gravity dam significantly reduces about 25% when the radiation damping of infinite foundation is considered. Hot interfaces and the normal cold interfaces have little influence on the dynamic response of the RCC gravity ***, nonlinear fracture along the cold interfaces at the dam heel will occur under the designed earthquake if the cold interfaces are combined poorly. Therefore, to avoid the fractures along the construction interfaces under the potential super earthquakes,combination quality of the RCC layers should be significantly ensured.

关键词： roller compacted concrete dam construction interface nonlinear fracture radiation damping viscous-spring artificial boundary dynamic response

A new method based on two freedom-degree PD-P flow rate controller for congestion control in computer networks

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High Technology Letters 2005年第3期11卷 257-262页

作者： Shen Wei（沈伟） Feng rui shao Huihe Institute of Automation Shanghai Jiaotong University Shanghai 200030 P. R. China

The rate-based feedback PD-P controller of two freedom-degrees is proposed for the congestion control in computer networks to improve the abilities against disturbance. Moreover, the Dahlin algorithm is used for setting the controller to overcome the adverse effect caused by the propagation delay effectively. The research results show that the proposed scheme not only can make sources respond to the changes of network state more quickly, but also has a good robustness against estimated error of the delay. Then the packet queue level in buffer will be stabilized on the set-point quickly, and the delay and its jitter of the packet queuing will also become smaller. Besides, the flexible bandwidth allotment can be obtained by setting the weight coefficients.

关键词： computer networks flow rate control two freedom-degrees

Microwave-assisted Preparation of Temperature Sensitive Poly(N-isopropylacrylamide) Hydrogel with Improved Responsive Properties

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Chinese Chemical Letters 2006年第3期17卷 361-364页

作者： shao Hua shi Li Jian LIU Department of Polymer Science College of Chemistry and Molecular Science Wuhan University Key Laboratory of Biomedical Polymers （Wuhan University） Ministry of Education Wuhan 430072 R ＆ D Center Nhwa Pharmaceutical Group Xuzhou 221007

Poly（N-isopropylacrylamide）-based hydrogel was prepared under microwave irradiation The hydrogel thus prepared, comparing with that prepared by thermal heating method, exhibits faster swelling and shrinking kinetics. The improved responsive properties are due to the more heterogeneous and porous networks formed under microwave irradiation.

关键词： Microwave poly(N-isopropylacrylamide) hydrogel fast response.

Astronomical image restoration using variational Bayesian blind deconvolution

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Journal of Systems Engineering and Electronics 2017年第6期28卷 1236-1247页

作者： Xiaoping shi rui Guo Yi Zhu Zicai Wang Control and Simulation Center Harbin Institute of Technology Harbin 150080 China

An algorithm is presented for image prior combinations based blind deconvolution and applied to astronomical *** a hierarchical Bayesian framework, the unknown original image and all required algorithmic parameters are estimated simultaneously. Through utilization of variational Bayesian analysis,approximations of the posterior distributions on each unknown are obtained by minimizing the Kullback-Leibler(KL) distance, thus providing uncertainties of the estimates during the restoration process. Experimental results on both synthetic images and real astronomical images demonstrate that the proposed approaches compare favorably to other state-of-the-art reconstruction methods.

关键词： blind deconvolution variational Bayesian model com bination astronomical image processing

Preparation and Interfacial Stability of SiC_f/Ti-6Al-4V Composites Fabricated Using Powder Coated Fiber Method

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Journal of Materials Science & Technology 2005年第6期21卷 903-908页

作者： Yanhua LI Dezhi ZHANG Nanlin shi rui YANG Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China College of Environment and Chemical Engineering Dalian University Dalian 116622 China

SiCf/Ti-6Al-4V composites were fabricated by the powder-coated fiber method. The precursor fiber was prepared under the optimized parameter, and the composites were made using the vacuum hot pressure method. The influence of heat exposure time on products of thelinterfacial reaction was investigated using scanning electron microscope （SEM） and analytical transmission electron microscope （TEM） with energy dispersive spectrometer （EDS）. The main products are TiC and Ti5Si3 after vacuum exposing the samples at 700℃ for 50 h. The growth dynamics of interracial reaction products was analyzed quantitatively, which fitted the parabola rule. The activity energy of the reaction was 252 kJ·mol^-1.

关键词： Powder coated fiber SiCf/Ti-6Al-4V composites Interfacial reaction Kinetic Activity energy

Effect of CuO Particle Size on the Microstructure Evolution of Al_2O_(3P)/Al Composites Prepared Via Displacement Reactions in the Al/CuO System

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Acta Metallurgica Sinica(English Letters) 2015年第6期28卷 699-706页

作者： Ge Zhao Zhi-Ming shi rui-Ying Zhang School of Materials Science and Engineering Inner Mongolia University of Technology

An A1203p/A1 composite was successfully synthesized using a displacement reaction between 80 wt% A1 and 20 wt% CuO powders at a heating rate of 5 ℃/min. Two different sizes CuO particles were used, and all the experiments were conducted under an argon atmosphere. To analyze the microstructural evolution during synthesis, the A1-20 wt% CuO samples were heated to the temperatures selected according to the differential scanning calorimetry curve and then immediately quenched with water. The phase composites and microstructure of the water-quenching samples were in- vestigated using X-ray diffraction, optical microscopy, scanning electron microscopy and energy-dispersive spectrometry. The results indicate that the CuO particle size has a significant effect on the microstructural evolution of the samples during the heating stage and on the microstructure of synthesized composites. Smaller CuO particles can decrease the reaction temperature, narrow the reaction temperature range at the different reaction stages during the heating stage and make the size and distribution of in situ A1203 particles more uniform. The reaction between A1 and CuO can be complete as the temperature rises to 900 ℃. The size of the in situ A1203 particles is approximately 5 μm when the size of the CuO particles is less than 6 μm. This sample has a relatively high Rockwell hardness of 60 HRB.

关键词： AI203p/AI composite Displacement reaction CuO particles Particle size Microstructureevolution

Influence of flexible solar arrays on vibration isolation platform of control moment gyroscopes

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Acta Mechanica Sinica 2012年第5期28卷 1479-1487页

作者： Yao Zhang Jing-rui Zhang shi-Jie Xu School of Aerospace Engineering Beijing Institute of Technology School of Astronautics Beihang University

A high-performance vibration isolation platform （VIP） has been developed for a cluster of control moment gyroscopes （CMGs）. CMGs have long been used for satellite attitude control. In this paper, the influence of flexible solar arrays on a passive multi-strut VIP of CMGs for a satellite is analyzed. The reasonable parameters design of flexi- ble solar arrays is discussed. Firstly, the dynamic model of the integrated satellite with flexible solar arrays, the VIP and CMGs is conducted by Newton-Euler method. Then based on reasonable assumptions, the transmissibility matrix of the VIP is derived. Secondly, the influences of the flexible solar arrays on both the performance of the VIP and the stability of closed-loop control systems are analyzed in detail. The parameter design limitation of these solar arrays is discussed. At last, by selecting reasonable parameters for both the VIP and flexible solar arrays, the attitude stabilization performance with vibration isolation system is predicted via simulation.

关键词： Control moment gyroscope Vibration isolationplatform Attitude control Ultra quiet platform