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Damaging Effect of Cigarette Smoke Extract on PrimaryCultured Human Umbilical Vein Endothelial Cells and Its Mechanism

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Biomedical and Environmental Sciences 2004年第2期17卷 121-134页

作者： Yu-MEIYANG geng-TAOLIU DivisionofPharmacology InstituteofMateriaMedicaChineseAcademyofMedicalSciencesPekingUnionMedicalCollege1XianNongTanStreetBeijing100050China

Objective To investigate the cellular effects of cigarette smoke extract (CSE) on primarily cultured human umbilical vein endothelial cells (HUVEC). Methods The effects of CSE (5%-20%) and nicotine (10-4 mol/L) on HUVEC viability, proliferation, angiogenesis and apoptosis were observed. Results CSE decreased HUVEC survival rate and angiogenesis after 24 h as well as its proliferation after 48 h in a dose-dependent manner. Moreover, CSE induced apoptosis of HUVEC as indicated in condensation of nuclear chromatin and the presence of hypodiploid DNA. HUVEC incubated with CSE for 24 h gave a significant decrease in the expression of Bcl-2 as well as the decline in the Bcl-2/Bax ratio accompanied with the loss of mitochondrial membrane potential and excess cytosolic calcium. Our study also observed that p53 protein level decreased, rather than increased in cells treated with CSE. Nicotine had no discernible inhibitory effects on the above indices of HUVEC. Conclusion Exposure to CSE other than nicotine causes inhibition of viability, proliferation and differentiation of HUVEC. CSE-induced HUVEC injury is mediated in part through accelerated apoptosis but independent of p53 pathway. It appears that mitochondria have played a key role in the apoptosis of HUVEC induced by CSE.

关键词： Cigarette smoke extracts (CSE) Human umbilical endothelial cell (HUVEC) Viability Proliferation Angiogenesis Mitochondrial membrane potential Cytosolic calcium Bcl-2 Bcl-2/Bax p53

Effect of Shot Blasting on Oxidation Behavior ofTP304H Steel at 610℃-770℃ in Water Vapor

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材料热处理学报 2004年第05B期25卷 1214-1218页

作者： FUMin LIXin-geng HEJa-wen ShandongElectricPowerResearchInstituteofChina JinanChina StateKeyLaboratoryforMechanicalBehaviorofMaterials Xi＇anJiaotongUniversityXi＇anChina ShandongElectricPowerResearchInstituteofChina JinanChina／／StateKeyLaboratoryforMechanicalBehaviorofMaterialsXi＇anJiaotongUniversityXi＇anChina

Shot blasting on a tube steel of TP304H can greatly improve the oxidation resistance at *50°C—770°C in water vapor, by the presence of an appropriate blasting intensity. SEM and EPMA analysis indicated that the structure of the oxide scale turned from multi-layer to monolayer after blasting and Cr2O3 in predominant. The untreated sample characterized in multi-layer oxide was composed of Fe in the outer layer and Fe and Cr underneath. For blasted one, the increase of diffusion rate of Cr and the decrease of effective diffusion energy of scale led to a uniform Cr-rich oxide layer, which was dense and protective and the oxidation resistance was increased.

关键词： TP304H EPMA SEM Cr2O3

Single-Machine Preemptive Scheduling with Release Dates Involving the Total Weighted Late Work Criterion

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Journal of the Operations Research Society of China 2023年第3期11卷 693-706页

作者： Zhi-Chao geng Yuan Zhang School of Mathematics and Statistics Zhengzhou UniversityZhengzhouHenan450001China

This paper investigates the preemptive scheduling with release dates on a single machine to minimize the total weighted late *** firstly present an O(nlogn)-time algorithm for the single-agent problem with disagreeable weights and due *** then,we extendedly study the two-agent Pareto-scheduling problem with jobs having a common due date to minimize each agent's total weighted late work,and give a polynomial-time algorithm that is based on the parameters analysis to generate the Pareto frontier.

关键词： Preemptive scheduling Total weighted late work Two agent Pareto frontier

Model-based diagnosis of incomplete discrete-event system with rough set theory

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Science China(Information Sciences) 2017年第1期60卷 190-200页

作者： Xuena geng Dantong OUYANG Yonggang ZHANG Key Laboratory of Symbolic Computation and Knowledge Engineering Ministry of EducationJilin University College of Computer Science and Technology Jilin University

Fault diagnosis of discrete-event system(DES) is important in the preventing of harmful events in the system. In an ideal situation, the system to be diagnosed is assumed to be complete; however, this assumption is rather restrictive. In this paper, a novel approach, which uses rough set theory as a knowledge extraction tool to deal with diagnosis problems of an incomplete model, is investigated. DESs are presented as information tables and decision tables. Based on the incomplete model and observations, an algorithm called Optimizing Incomplete Model is proposed in this paper in order to obtain the repaired model. Furthermore, a necessary and sufficient condition for a system to be diagnosable is given. In ensuring the diagnosability of a system, we also propose an algorithm to minimize the observable events and reduce the cost of sensor selection.

关键词： model-based diagnosis diagnosability discrete-event system finite state machine rough set theory

Mass balance calculation of the pyrolysates generated from marine crude oil:A prediction model of oil cracking gas resources based on solid bitumen in reservoir

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Chinese Science Bulletin 2007年第11期52卷 1532-1539页

作者： WANG TongShan geng AnSong XIONG YongQiang geng XinHua State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Oil cracking gas plays an important role in the resources of natural gas in the basins with high and over mature marine source rocks in China. The prediction of the oil cracking gas resources becomes nec-essary and urgent in the gas exploration in these basins. A marine crude oil sample was pyrolyzed using sealed gold tubes system. The pyrolysates including gas,liquid and solid were quantitatively analyzed. Based on the pyrolysis data and kinetic calculation,the yield correlativity among gas,liquid and solid products was regressed with high correlative coefficients to establish a prediction model suitable for the resource estimation of oil cracking gas. The verification formula for this model was also established on the principle of mass conservation. The affecting factors and the application precondi-tions of this prediction model were discussed. This model would enlighten and provide some new ideas for the resource assessment of natural gas in the high and over mature marine carbonate source rock areas in China. It is expected to be valuable in gas exploration.

关键词：高温分解实验石油天然气故障预测相互关系

Codes cross-correlation analysis and data/pilot code pairs optimization for Galileo E1 OS and GPS L1C

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Chinese Journal of Aeronautics 2013年第3期26卷 751-765页

作者： Yang Zaixiu Huang Zhigang geng Shengqun School of Electronic and Information Engineering Beihang University

The Galileo E1 open service （OS） and the global positioning system （GPS） L1C are intending to use the multiplexed binary offset carrier （MBOC） modulation in E1/L1 band, including both pilot and data components. The impact of data and pilot codes cross-correlation on the distortion of the discriminator function （i.e., the S-curve） is investigated, when only the pilot （or data） components of MBOC signals are tracked. It is shown that the modulation schemes and the receiver configuration （e.g., the correlator spacing） strongly affect the S-curve bias. In this paper, two methods are proposed to optimize the data/pilot code pairs of Galileo E1 OS and GPS L1C. The optimization goal is to obtain the minimum average S-curve bias when tracking only the pilot components a the specific correlator spacing. Figures of merit, such as S-curve bias, correlation loss and code tracking variance have been adopted for analyzing and comparing the un-optimized and optimized code pairs. Simulation results show that the optimized data/pilot code pairs could significantly mitigate the intra-channel codes cross-correlation, and then improve the code tracking performance of MBOC signals.

关键词： Code cross-correlation Code pair optimization Galileo Global positioning system Multiplexed binary offset carrier S-curve bias

Dependence of the surface-assisted fullerene-based complex structure on the template molecule design

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Nano Research 2019年第7期12卷 1509-1537页

作者： Yanfang geng Qingdao Zeng Chen Wang CAS Key Laboratory of Standardization and Measurement for Nanotechnology CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China

Fullerene derivatives as a kind of star carbon materials have received intense investigation because of their three-dimensional shape,anisotropic electron mobility,and high electron ***,the cutting-edge developments of fullerene nanomaterials have had a tremendous impact on a wide range of applications,such as organic solar cells,field effect transistors,and *** explore their full potential applications,research into fullerene-based multilevel nanostructures relying on hierarchical interactions from bottom to top is rapidly *** is of great theoretical and practical significance to prepare multilevel fullerene nanostructures with structural and properties controlled by optimizing the influencing *** review would offer several aspects including the chemical structures of organic molecules and the nanostructures of the organic molecules and fullerene-organic *** monolayers or multilayers,fullerene molecules tend to fall into a space of suitable size,in which the located positions are affected by the intermolecular *** the covered surfaces,fullerenes are more likely to approach the electron-withdrawing units through the donor-acceptor and charge transfer *** the implementation of this review,an exhaustive analysis on the chemical modification,including the molecular backbone and substituents,preformed network synergies,and adsorption sites is *** addition,the relationship between the molecules and structures that illustrates the importance of the molecular design for the controlled fullerenes hybrid nanostructures can be further understood based on the results of the joined experimental and computational investigations.

关键词： fullerene organic molecule nanostructure property molecular design

Experimental investigation of influence of strake wings on self-induced roll motion at high angles of attack

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Chinese Journal of Aeronautics 2016年第6期29卷 1591-1601页

作者： geng Xi Shi Zhiwei Cheng Keming College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics

The modern high performance air vehicles are required to have extreme maneuverability,which includes the ability of controlled maneuvers at high angle of attack. However, the nonlinear and unsteady aerodynamic phenomena, such as flow separation, vortices interaction, and vortices breaking down, will occur during the flight at high angle of attack, which could induce the uncommanded motions for the air vehicles. For the high maneuverable and agile air missile, the nonlinear roll motions would occur at the high angle of attack. The present work is focused on the selfinduced nonlinear roll motion for a missile configuration and discusses the influence of the strake wings on the roll motion according to the results from free-to-roll test and PIV measurement using the models assembled with different strake wings at a = 60°. The free-to-roll results show that the model with whole strake wings(baseline), the model assembled with three strake wings(Case A)and the model assembled with two opposite strake wings(Case C) experience the spinning, while the model assembled with two adjacent strake wings(Case B), the model assembled with one strake wing(Case D) and the model with no strake wing(Case E) trim or slightly vibrate at a certain "×"rolling angle, which mean that the rolling stability can be improved by dismantling certain strake wings. The flow field results from PIV measurement show that the leeward asymmetric vortices are induced by the windward strake wings. The vortices would interact the strake wings and induce crossflow on the downstream fins to degrade the rolling stability of the model. This could be the main reason for the self-induced roll motion of the model at a = 60°.

关键词： Cruciform fins High angle of attack PIV Roll motion Strake wing

Topological origin of global attractors in gene regulatory networks

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Science China(Physics,Mechanics & Astronomy) 2015年第2期58卷 101-108页

作者： ZHANG YunJun OUYANG Qi geng Zhi Faculty of Foundation Education Peking University Health Science Center Center for Theoretical Biology School of Physics Peking University School of Mathematical Sciences Peking University

Fixed-point attractors with global stability manifest themselves in a number of gene regulatory networks. This property indicates the stability of regulatory networks against small state perturbations and is closely related to other complex dynamics. In this paper, we aim to reveal the core modules in regulatory networks that determine their global attractors and the relationship between these core modules and other motifs. This work has been done via three steps. Firstly, inspired by the signal transmission in the regulation process, we extract the model of chain-like network from regulation networks. We propose a module of "ideal transmission chain(ITC)", which is proved sufficient and necessary(under certain condition) to form a global fixed-point in the context of chain-like network. Secondly, by examining two well-studied regulatory networks(i.e., the cell-cycle regulatory networks of Budding yeast and Fission yeast), we identify the ideal modules in true regulation networks and demonstrate that the modules have a superior contribution to network stability(quantified by the relative size of the biggest attraction basin). Thirdly, in these two regulation networks, we find that the double negative feedback loops, which are the key motifs of forming bistability in regulation, are connected to these core modules with high network stability. These results have shed new light on the connection between the topological feature and the dynamic property of regulatory networks.

关键词： Boolean model bistability network module robustness