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Establishing Gene Delivery Systems Based on Small-Sized Chitosan Nanoparticles

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Journal of Ocean University of China 2018年第5期17卷 1253-1260页

作者： WANG Liping ZHANG wenhua ZHOU Quan LIU Shihai XU wenhua SUN Teng LIANG Ye Key Laboratory Department of Urology and AndrologyAffiliated Hospital of Qingdao University Department of Inspection Qingdao University Central Laboratory Affiliated Hospital of Qingdao University Laboratory Animal Center Affiliated Hospital of Qingdao University Department of Outpatient Affiliated Hospital of Qingdao University

Chitosan is a natural cationic polysaccharide, which is often used for preparing biomedical materials because of its high biocompatibility. In this study, chitosan with a molecular weight of 160 kDa was chosen to prepare chitosan nanoparticles （CSNPs） as gene vectors by ionic cross-linking with tripolyphosphate （TPP）. CSNPs were characterized in terms of particle size, zeta potential, and polydispersity index （PDI） using a Zetasizer, and morphology was evaluated by transmission electron microscopy （TEM）. Furthermore, the cytotoxicity and biocompatibility of CSNPs were correspondingly examined by a 3-（4,5-dimethylthiazol-2-yl）-2,5- diphenyltetrazolium bromide （MTT） assay and histological examination. Agarose gel electrophoresis and UV spectrophotometric methods were performed to measure the loading capacity. The cell transfection efficiency of CSNPs loaded with plasmids or siRNA was analyzed by fluorescence microscopy or laser scanning confocal microscopy. The results showed that CSNPs were prepared successfully by the ionic gelation method, which had a smaller partcticle size （100 nm-200 nm）, stable dispersibility, low cytotoxicity, good tissue-biocompatibility, and high gene-loading efficiency. These CSNPs could transfer the plasmids or siRNA to cells. However, CSNPs might have a much higher transfection efficiency for siRNAs than for plasmids, which implies that CSNPs might be a safer and more efficient vector for delivering siRNAs rather than plasmids.

关键词： chitosan nanoparticles gene delivery

Time-dependent relativistic density functional study of Yb and YbO

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Science China Chemistry 2009年第11期52卷 1945-1953页

作者： XU wenhua ZHANG Yong LIU WenJian Beijing National Laboratory for Molecular Sciences Institute of Theoretical and Computational ChemistryState Key Laboratory of Rare Earth Materials Chemistry and ApplicationsCollege of Chemistry and Molecular Engineeringand Center for Computational Science and EngineeringPeking UniversityBeijing 100871China

The low-lying electronic states of Yb and YbO are investigated by using time-dependent relativistic density functional theory,which is based on the newly developed exact two-component Hamiltonian resulting from symmetrized elimination of the small *** nature of the excited states is analyzed by using the full molecular *** calculated results support the previous experimental assignment of the ground and excited states of YbO.

关键词： lanthanide compound excited states f-orbital transitions time-dependent relativistic density functional theory exact two-component Hamiltonian

Elementary Wave Interactions for the Simplified Combustion Model in Magnetogasdynamics

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Journal of Applied Mathematics and Physics 2019年第4期7卷 983-1000页

作者： Yujin Liu wenhua Sun School of Mathematics and Statistics Shandong University of Technology Zibo China

We investigate the elementary wave interactions for the simplified combustion model in magnetogasdynamics. Under the modified entropy conditions, we construct the unique solution and observe some interesting phenomena;such as, the combustion wave may be extinguished by the contact discontinuity or the shock wave. Especially, the transition between the detonation wave and the deflagration wave is also captured.

关键词： Riemann Problem Wave Interaction Hyperbolic Conservation Laws Combustion Magnetogasdynamics

An upper bound for the adiabatic approximation error

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Science China(Physics,Mechanics & Astronomy) 2014年第2期57卷 218-224页

作者： WANG wenhua GUO ZhiHua CAO HuaiXin College of Mathematics and Information Science Shaanxi Normal University

In this paper, we derive an upper bound for the adiabatic approximation error, which is the distance between the exact solution to a Schrodinger equation and the adiabatic approximation solution. As an application, we obtain an upper bound for 1 minus the fidelity of the exact solution and the adiabatic approximation solution to a SchrOdinger equation.

关键词： upper bound error adiabatic approximation

A Study on Fraud Reviews: Incentives to Manipulate and Effect on Sales

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China Communications 2019年第3期16卷 165-178页

作者： Tao Yin Wenqi Wang wenhua Shi School of Economics and Management Beijing University of Posts and Telecommunications

With the broad reach of Internet, online reviews have become an important source of electronic Word-of-Mouth. Fraud reviews that are deliberately posted by businesses are a type of online reviews. This paper discusses the incentives of fraud reviews and the effect of fraud reviews on consumer behavior through empirical research. Using book download data at Amazon, we find that a book is more likely to manipulate fraud reviews when it has few online reviews posted by real consumers, higher proportion of negative reviews, longer average length of negative reviews, lower average rating scored by real users and higher price. And fraud reviews change the review environment and have a significant impact on the consumer purchasing decisions. More number, higher proportion, longer word count and higher promotion of rating of fraud reviews lead to higher sales. The results also show consumers can discern the manipulation of fraud reviews to a certain extent.

关键词： electronic word of mouth online reviews fraud reviews purchasing decision

A novel method for internal wave monitoring based on expansion of the sound speed profile

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Acta Oceanologica Sinica 2019年第4期38卷 183-189页

作者： Ke Qu Fengqin Zhu wenhua Song Guangdong Province Key Laboratory for Coastal Ocean Variation and Disaster Prediction Guangdong Ocean University College of Electronics and Information Engineering Guangdong Ocean University College of Information Science and Engineering Ocean University of China

For acoustic detection of internal waves, the core issue is to obtain the temporal and spatial distribution of the sound speed profile(SSP). In the inversion process, the SSP is usually expressed by a few parameters through expansion. However, information about internal waves may sometimes be hard to read directly from the inversion results. The aim of this paper is to characterize the internal waves directly though expansion coefficients. By deducing the dynamic equations of the internal waves, an orthogonal basis called the hydrodynamic normal modes(HNMs) can be extracted from a certain number of SSP samples. Unlike the existing widely used empirical orthogonal functions(EOFs), the HNMs have a more explicit physical meaning that is directly related to internal wave activity. The HNMs are then used to expand the SSP time series, and the expansion coefficients are ***, information about internal waves can be read directly from the time derivative of the expansion coefficients of the first two modes. In this study, this method is applied to thermistor string profiles from the northern shelf of the South China Sea, where the SSP shows evident spatial and temporal variations due to internal waves. The results show that the SSP can be described approximately by the first two modes with adequate precision. The special oscillation structure of the time derivative of the expansion coefficients can be used to detect internal solitary waves. The expansion coefficients can also give information on internal solitary wave amplitude and width. According to theoretical and experimental analysis, it can be concluded that the internal waves monitoring method introduced in this paper is effective. The HNMs method is simple to apply and depends less on sample data than EOFs. It could be used as an efficient alternative to EOFs to expand the use of the SSP in highly variable areas, where internal waves are intensive.

关键词： internal waves hydrodynamic normal modes internal solitary waves South China Sea

Pedestrian Attributes Recognition in Surveillance Scenarios with Hierarchical Multi-Task CNN Models

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China Communications 2018年第12期15卷 208-219页

作者： wenhua Fang Jun Chen Ruimin Hu National Engineering Research Center for Multimedia Software Computer School of Wuhan UniversityWuhan 430072China Hubei Key Laboratory of Multimedia and Network Communication Engineering Wuhan UniversityWuhan 430072China Collaborative Innovation Center of Geospatial Technology Wuhan 430079China

Pedestrian attributes recognition is a very important problem in video surveillance and video forensics. Traditional methods assume the pedestrian attributes are independent and design handcraft features for each one. In this paper, we propose a joint hierarchical multi-task learning algorithm to learn the relationships among attributes for better recognizing the pedestrian attributes in still images using convolutional neural networks(CNN). We divide the attributes into local and global ones according to spatial and semantic relations, and then consider learning semantic attributes through a hierarchical multi-task CNN model where each CNN in the first layer will predict each group of such local attributes and CNN in the second layer will predict the global attributes. Our multi-task learning framework allows each CNN model to simultaneously share visual knowledge among different groups of attribute categories. Extensive experiments are conducted on two popular and challenging benchmarks in surveillance scenarios, namely, the PETA and RAP pedestrian attributes datasets. On both benchmarks, our framework achieves superior results over the state-of-theart methods by 88.2% on PETA and 83.25% on RAP, respectively.

关键词： attributes recognition CNN multi-task learning

Effects of Freestream Turbulence,Reynolds Number and Mach Number on the Boundary Layer in a Low Pressure Turbine

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Journal of Thermal Science 2023年第4期32卷 1393-1406页

作者： DUAN wenhua QIAO Weiyang CHEN Weijie ZHAO Xinyu Turbomachinery Aerodynamics and Acoustics Lab(TAAL) School of Power and EnergyNorthwestern Polytechnical UniversityXi’an710129China

In order to investigate the aerodynamics of a high speed low pressure turbine works in high Mach number and low Reynold number environment,the effect of freestream turbulence(FST)on the boundary layer development on the high speed low pressure turbine under different Reynolds numbers(Re)is numerically *** eddy simulation is adopted here with a subgrid scale model of Wall Adapting Local Eddy viscosity(WALE).Cases with Re ranging from 100000 to 400000 under an exit Mach number(Ma)of 0.87 have been considered at low and high FST levels.A low Ma case(0.17)under very low Re has also been studied under both low and high *** is found that higher Re or FST level leads to earlier *** has a greater effect than FST on the development of boundary *** effect of FST on the boundary layer depends on the *** boundary layer development shows totally different behaviors under different Ma.A separation bubble could be formed under low Ma while no attachment could be detected under high *** FST has a stronger effect on the separated boundary layer under low Ma,which could eliminate the separation in the present *** all the cases under low FST,the Kelvin-Helmholtz instability is the dominate mechanism in the transition *** the low Ma case with high FST,the streamwise streaks play a dominant role in the transition *** the high Ma cases with high FST,both the streamwise streaks and Kelvin-Helmholtz instability work in the transition *** streamwise streaks play a more important role when the Re increased.

关键词： freestream turbulence Reynolds number Mach number low pressure turbine boundary layer

Adaptive fuzzy tracking control for a class of uncertain MIMO nonlinear systems using disturbance observer

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Science China(Information Sciences) 2014年第1期57卷 246-258页

作者： CHEN Mou CHEN wenhua WU QinXian College of Automation Engineering Nanjing University of Aeronautics and Astronautics Department of Aeronautical and Automotive Engineering Loughborough University Loughborough

In this paper,the adaptive fuzzy tracking control is proposed for a class of multi-input and multioutput(MIMO)nonlinear systems in the presence of system uncertainties,unknown non-symmetric input saturation and external *** logic systems(FLS)are used to approximate the system uncertainty of MIMO nonlinear ***,the compound disturbance containing the approximation error and the timevarying external disturbance that cannot be directly measured are estimated via a disturbance *** appropriately choosing the gain matrix,the disturbance observer can approximate the compound disturbance well and the estimate error converges to a compact *** control strategy is further extended to develop adaptive fuzzy tracking control for MIMO nonlinear systems by coping with practical issues in engineering applications,in particular unknown non-symmetric input saturation and control *** this setting,the disturbance observer technique is combined with the FLS approximation technique to compensate for the efects of unknown input saturation and control *** approach based analysis shows that semi-global uniform boundedness of the closed-loop signals is guaranteed under the proposed tracking control *** simulation results are presented to illustrate the efectiveness of the proposed tracking control schemes.

关键词： MIMO nonlinear system input saturation disturbance observer fuzzy logic systems tracking control