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Atorvastatin Attenuates TNF-alpha Production via Heme Oxygenase-1 Pathway in LPS-stimulated RAW264.7 Macrophages

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Biomedical and Environmental Sciences 2014年第10期27卷 786-793页

作者： WANG Xiao Qiao LUO Nian Sang CHEN zhong Qing lin Yong Qing GU Miao ning CHEN Yang Xin Department of Anesthesiology Nanfang Hospital of Southern Medical University Department of Anesthesiology the Second Affiliated Hospital of Guangzhou Medical University Department of Cardiology Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University Guangdong Provincial Key Laboratory of Arrhythmia and Electrophysiology Department of Surgery Intensive Care Unit Nanfang Hospital of Southern Medical University

Objective To assess the effect of atorvastatin on lipopolysaccharide （LPS）-induced TNF-a production in RAW264.7 macrophages. Methods RAW264.7 macrophages were treated in different LPS concentrations or at different time points with or without atorvastatin. TNF-a level in supernatant was measured. Expressions of TNF-a mRNA and protein and heme oxygenase-1 （HO-1） were detected by ELISA, PCR, and Western blot, respectively. HO activity was assayed. Results LPS significantly increased the TNF-a expression and secretion in a dose- and time-dependent manner. The HO-1 activity and HO-1 expression level were significantly higher after atorvastatin treatment than before atorvastatin treatment and attenuated by SB203580 and PD98059 but not by SP600125, suggesting that the ERK and p38 mitogen-activated protein kinase （MAPK） pathways participate in regulating the above-mentioned effects of atorvastatin. Moreover, the HO-1 activity suppressed by SnPP or the HO-1 expression inhibited by siRNA significantly attenuated the effect of atorvastatin on TNF-c~ expression and production in LPS-stimulated macrophages. Conclusion Atorvastatin can attenuate LPS-induced TNF-e expression and production by activating HO-1 via the ERK and p38 MAPK pathways, suggesting that atorvastatin can be used in treatment of inflammatory diseases such as sepsis, especially in those with atherosclerotic diseases.

关键词： Lipopolysaccharide Tumor necrosis factor-a Heme oxygenase-1 Atorvastatin

A step parameters prediction model based on transfer process neural network for exhaust gas temperature estimation after washing aero-engines

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Chinese Journal of Aeronautics 2022年第3期35卷 98-111页

作者： Zhiqi YAN Shisheng zhong lin lin Zhiquan CUI Minghang ZHAO School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China Department of Vehicle Engineering Harbin Institute of TechnologyWeihai 264209China School of Naval Architecture and Ocean Engineering Harbin Institute of TechnologyWeihai 264209China

The prediction of Exhaust Gas Temperature Margin(EGTM)after washing aeroengines can provide a theoretical basis for airlines not only to evaluate the energy-saving effect and emission reduction,but also to formulate reasonable maintenance ***,the EGTM encounters step changes after washing aeroengines,while,in the traditional models,a persistence tendency exists between the prediction results and the previous data,resulting in low accuracy in *** order to solve the problem,this paper develops a step parameters prediction model based on Transfer Process Neural Networks(TPNN).Especially,“step parameters”represent the parameters that can reflect EGTM step *** are analyzed in this study,and thus the model concentrates on the prediction of step changes rather than the extension of data *** learning is used to handle the problem that few cleaning records result in few step changes for model *** comparison with Long Short-Term Memory(LSTM)and Kernel Extreme Learning Machine(KELM)models,the effectiveness of the proposed method is verified on CFM56-5B engine data.

关键词： Aero-engine washing Data step changes Exhaust Gas Temperature Margin(EGTM) Neural networks Transfer learning

Dynamic mechanical behavior and the constitutive model of concrete subjected to impact loadings

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Science China(Physics,Mechanics & Astronomy) 2008年第11期51卷 1745-1760页

作者： ning JianGuo LIU HaiFeng SHANG lin State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Civil and Hydraulic Engineering Ningxia UniversityYinchuan 750021China

Based on the theory of consecutive damage mechanics, micro-mechanics, statis-tics and the visco-plastic constitutive equation of Perzyna, a coupled model of damage and plasticity is developed to describe the complex behavior of concrete subjected to impact loadings. In this model, some suppositions about deformation of the material and evolution of the damage are made. First, concrete is macro-scopically assumed to be homogeneous and consecutive, while it is microscopi-cally filled with large amounts of micro-crack and micro-void defects. Second, the damage evolution of the micro-cracks is caused by the nucleation, growth and coalescence of the micro-cracks due to the interior tensile stress in concrete, which leads to a degradation in the strength and stiffness of concrete. Third, compaction of concrete is physically a collapse of the material micro-void. It pro-duces irreversible plastic strains in the material and, at the same time, an increase in the bulk modulus. Fourth, there is no interaction between the micro-crack and the micro-void. Last, when the damage reaches a critical value, the concrete may fail totally. The model parameters for concrete are determined by plate impact ex-periments. The model predictions fit the experimental results well. So the model can be used to simulate the dynamic mechanical behavior of concrete under impact loadings.

关键词： concrete impact behavior damage evolution constitutive model

One-Dimensional ZnO Nanostructures： Solution Growth and Functional Properties

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Nano Research 2011年第11期4卷 1013-1098页

作者： Sheng Xu zhong lin Wang School of Materials Science and Engineering Georgia Institute of Technology Atlanta Georgia 30332-0245 USA

One-dimensional （1D） ZnO nanostructures have been studied intensively and extensively over the last decade not only for their remarkable chemical and physical properties, but also for their diverse current and future technological applications. This article gives a comprehensive overview of the progress that has been made within the context of 1D ZnO nanostructures synthesized via wet chemical methods. We will cover the synthetic methodologies and the corresponding growth mechanisms, various nanostructures grown, their doping and alloying, and position-controlled growth on substrates. Finally, we will review their functional properties in catalysis, hydrophobic surface modification, sensing, and electronic, optical, optoelectronic, and energy harvesting devices.

关键词： ZnO one dimensional nanostructures solution growth electronic optical optoelectronic energy harvesting devices

Contact Electrification by Quantum-Mechanical Tunneling

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Research 2019年第1期2019卷 742-752页

作者： Morten Willatzen zhong lin Wang CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-Nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 100083China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA 30332-0245USA

A simple model of charge transfer by loss-less quantum-mechanical tunneling between two solids is *** model is applicable to electron transport and contact electrifcation between e.g.a metal and a dielectric *** on a one-dimensional efective-mass Hamiltonian,the tunneling transmission coefcient of electrons through a barrier from one solid to another solid is calculated *** transport rate(current)of electrons is found using the Tsu-Esaki equation and accounting for diferent Fermi functions of the two *** show that the tunneling dynamics is very sensitive to the vacuum potential versus the two solids conduction-band edges and the thickness of the vacuum *** relevant time constants for tunneling and contact electrifcation,relevant for triboelectricity,can vary over several orders of magnitude when the vacuum gap changes by one order of magnitude,say,1˚A to 10˚*** repulsion between electrons on the lef and right material surfaces is accounted for in the tunneling dynamics.

关键词： tunneling solids vacuum

Triboelectric nanogenerator as a new technology for effective PM2.5 removing with zero ozone emission

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Progress in Natural Science:Materials International 2018年第2期28卷 99-112页

作者： Chuan He zhong lin Wang Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences School of Materials Science and Engineering Georgia Institute of Technology CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology (NCNST)

Particles matters(PMs) have raised serious concerns due to their great impact on human health. Coupling triboelectric effect and electrostatic induction, triboelectric nanogenerator(TENG) has demonstrated as a practical sustainable power source for portable devices. The characteristics of TENG, such as high electric field and high output power, make it a promising technology in air cleaning applications. Here, the mechanism of the TENG and its application in self-powered air cleaning technologies are reviewed. Using the TENG as a voltage source, a self-powered air cleaning system for removing SOand PMs is developed; and the removal efficiency of nanofiber filters is greatly enhanced due to electrostatic attraction. More importantly, the technology is not only most effective for removing nano-scale particles that cannot be effectively filtered using conventional fiber-film filters, but also produces no ozone emission. Besides being an independent power supply, a vibration TENG based triboelectric filter is designed to effectively capture the PMs from automobile exhaust fumes. Hence, the TENG demonstrates its great potential in self-powered air cleaning applications.

关键词： Triboelectric nanogenerator Power source Particulate matter Air cleaning Nanofiber filter

A synthetic optically pumped gradiometer for magnetocardiography measurements

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Chinese Physics B 2020年第4期29卷 215-217页

作者： Shu-lin Zhang ning Cao Joint Laboratory of Bioimaging Technology and Applications CAS-SIMIT&MEDIShanghai 201899China State Key Laboratory of Functional Materials for Informatics Institute of Microsystem and Information Technology(SIMIT)Chinese Academy of Sciences(CAS)Shanghai 200050China Centre for Excellence in Superconducting Electronics Chinese Academy of SciencesShanghai 200050China Shanghai Medi Instruments Ltd. Shanghai 201899China

Magnetocardiography(MCG)measurement is important for investigating the cardiac biological ***,the extremely weak MCG signal was detected by using superconducting quantum interference devices(SQUIDs).As a room-temperature magnetic-field sensor,optically pumped magnetometer(OPM)has shown to have comparable sensitivity to that of SQUIDs,which is very suitable for biomagnetic *** this paper,a synthetic gradiometer was constructed by using two OPMs under spin-exchange relaxation-free(SERF)conditions within a moderate magnetically shielded room(MSR).The magnetic noise of the OPM was measured to less than 70 fT/Hz1/*** a baseline of 100 mm,noise cancellation of about 30 dB was *** was successfully measured with a signal to noise ratio(SNR)of about 37 *** synthetic gradiometer technique was very effective to suppress the residual environmental fields,demonstrating the OPM gradiometer technique for highly cost-effective biomagnetic measurements.

关键词： optically pumped magnetometer(OPM) magnetocardiography(MCG) gradiometer

Pollutant mixing and transport process via diverse transverse release positions in a multi-anabranch river with three braid bars

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Water Science and Engineering 2013年第3期6卷 250-261页

作者： Zu-lin HUA Wei JI ning-ning SHAN Wei WU Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of Education Hohai University College of Environment Hohai University National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University

A multi-anabranch river with three braid bars is a typical river pattern in nature, but no studies have been conducted to describe mixing characteristics of pollutants in the river. In this study, a physical model of a typical multi-anabranch river with three braid bars was established to explore the pollutant mixing characteristics in different branches. The multi-anabranch reach was separated into seven branches, B1, B2, B3, B4, B5, B6, and BT, by three braid bars. Five tracer release positions located 2.9 m upstream from the inlet section of the multi-anabranch reach were adopted, and the distances from the five positions to the left bank of the upstream main channel were 1/6B, 1/3B, 1/2B, 2/3B, and 5/6B （B is the width of the upstream main channel）, respectively. The longitudinal velocities and pollutant concentrations in the seven branches were measured. The planar flow field and mixing characteristics of pollutants from the bottom to the surface in the multi-anabranch river were obtained and analyzed. The results show that the pollutant release positions are the main influencing factors in the pollutant transport process, and the diversion points and pollutant release positions jointly influence the percentage ratios of the pollutant fluxes in branches B 1, B2, and B3 to the pollutant flux in the upstream main channel.

关键词： multi-anabranch river braid bar, pollutant mixing characteristic pollutanttransport process

Rotation errors in numerical manifold method and a correction based on large deformation theory

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Frontiers of Structural and Civil Engineering 2019年第5期13卷 1036-1053页

作者： ning ZHANG Xu LI Qinghui JIANG Xingchao lin School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing 100044China School of Civil and Architectural Engineering Wuhan UniversityWuhan 430072China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin Beijing 100038China

Numerical manifold method (NMM) is an effective method for simulating block system, however, significant errors are found in its simulation of rotation problems. Three kinds of errors, as volume expansion, stress vibration, and attenuation of angular velocity, were observed in the original NMM. The first two kind errors are owing to the small deformation assumption and the last one is due to the numerical damping. A large deformation NMM is proposed based on large deformation theory. In this method, the governing equation is derived using Green strain, the large deformation iteration and the open-close iteration are combined, and an updating strategy is proposed. The proposed method is used to analyze block rotation, beam bending, and rock falling problems and the results prove that all three kinds of errors are eliminated in this method.

关键词： numerical manifold method rotation large deformation Green strain open-close iteration