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The role of galectin-4 in physiology and diseases

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Protein & Cell 2016年第5期7卷 314-324页

作者： zhan-Qi Cao xiu-Li Guo Department of Pharmacology School of Pharmaceutical Sciences Shandong University Jinan 50012 China

Galectin-4, a tandem repeat member of the β-galactoside-binding proteins, possesses two carbohydraterecognition domains （CRD） in a single peptide chain. This lectin is mostly expressed in epithelial cells of the intestinal tract and secreted to the extracellular. The two domains have 40% similarity in amino acid sequence, but distinctly binding to various ligands. Just because the two domains bind to different ligands simultaneously, galectin-4 can be a crosslinker and crucial regulator in a large number of biological processes. Recent evidence shows that galectin-4 plays an important role in lipid raft stabilization, protein apical trafficking, cell adhesion, wound healing, intestinal inflammation, tumor progression, etc. This article reviews the physiological and pathological features of galectin-4 and its important role in such processes.

关键词： galectin-4 lipid raft crosslinker intestinalinflammation tumor progression

Simulation study on heat-affected zone of high-strain X80 pipeline steel

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Journal of Iron and Steel Research International 2017年第9期24卷 966-972页

作者： Ying Ci zhan-zhan zhang College of Information Science and Engineering Northeastern University School of Physical Science and Engineering Zhengzhou University

The microstructure evolution and impact-toughness variation of heat-affected zone（HAZ）in X80 highstrain pipeline steel were investigated via a welding thermal-simulation technique,Charpy impact tests,and scanning electron microscopy observations under different welding heat inputs and peak *** results indicate that when heat input was between 17 and 25kJ·cm^（-1）,the coarse-grained heat-affected zone showed improved impact *** the heat input was increased further,the martensite-austenite（M-A）islands transformed from fine lath into a massive ***,impact toughness was substantially *** the heat input was 20kJ·cm^（-1） and the peak temperature of the first thermal cycle was between 900 and 1300°C,a higher impact toughness was *** heat input was 20kJ·cm^（-1） and the peak temperature of the first thermal cycle was 1300°C,the impact toughness value at the second peak temperature of 900°C was higher than that at the second peak temperature of 800°C because of grain refining and uniformly dispersed M-A constituents in the matrix of bainite.

关键词： High-strain X80 pipeline steel Welding heat input Peak temperature Impact toughness Microstructure

Effects of dietary supplementation of probiotic,Clostridium butyricum,on growth performance,immune response,intestinal barrier function,and digestive enzyme activity in broiler chickens challenged with Escherichia coli K88

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Journal of Animal Science and Biotechnology 2016年第1期7卷 107-115页

作者： Ling zhang Lingling zhang xiu'an zhan Xinfu Zeng Lin Zhou Guangtian Cao An'guo Chen Caimei Yang College of Animal Science Zhejiang UniversityHangzhou 310058China College of Animal Science and Technology Zhejiang A&F University88 North Huancheng RoadLin'anZhejiang 311300China Zhejiang Huijia Biological Technology Ltd. Anji 313307China

Background： Colibacillosis caused by enterotoxigenic Escherichia coil （E. coil} results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varying degrees of resistance to different antibiotics. Therefore the use of probiotics is becoming accepted as an alternative to antibiotics. In this study, we evaluated the effects of Clostfidium butyricum （C. butyficum） on growth performance, immune response, intestinal barrier function, and digestive enzyme activity in broiler chickens challenged with Eschefichia coli （E. coil） K88. Methods： The chickens were randomly divided into four treatment groups for 28 days. Negative control treatment （NC） consisted of birds fed a basal diet without E. coil K88 challenge and positive control treatment （PC） consisted of birds fed a basal diet and challenged with E. coil K88. C. buO/ricum probiotic treatment （CB） consisted of birds fed a diet containing 2 x 107 cfu C. buO/ricum/kg of diet and challenged with E. coil K88. Colistin sulfate antibiotic treatment （CS） consisted of birds fed a diet containing 20 mg colistin sulfate/kg of diet and challenged with E. coil K88. Results： The body weight （BW） and average day gain （ADG） in the broilers of CB group were higher （P 〈 0.05） than the broilers in the PC group overall except the ADG in the 14-21 d post-challenge. The birds in CB treatment had higher （P 〈 0.05） concentration of tumor necrosis factor-a （TNF-a） at 3 and 7 d post-challenge, and higher （P 〈 0.05） concentration of interleukin-4 （IL-4） at 14 d post-challenge than those in the PC treatment group. The concentration of serum endotoxin in CB birds was lower （P 〈 0.05） at 21 d post-challenge, and the concentrations of serum diamine oxidase in CB birds were lower （P 〈 0.05） at 14 and 21 d post-challenge than in PC birds. Birds in CB treatment group had higher （P 〈 0.05） jejunum villi height than those in PC, NC, or CS treatment at 7, 14, and 21 d post-challenge. In c

关键词： Broiler chickens Clostridium butyricum Digestive enzyme activity Escherichia coli K88 Growth performance Immune response Intestinal barrier

Research on ultrasonic-assisted drilling in micro-hole machining of the DD6 superalloy

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Advances in Manufacturing 2020年第3期8卷 405-417页

作者： Xiao-Xiang Zhu Wen-Hu Wang Rui-Song Jiang zhan-Fei zhang Bo Huang xiu-Wei Ma School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an710072People’s Republic of China School of Aeronautics and Astronautics Sichuan UniversityChengdu610065People’s Republic of China

The DD6 nickel-based superalloy exhibits remarkably high temperature properties;therefore,it is employed as a crucial structural material in the aviation ***,this material is difficult to ***-assisted drilling(UAD)combines the characteristics of vibration processing technology and conventional drilling technology,significantly improving the machinability of difficult-to-machine ***,UAD experiments were performed on micro-hole machining of DD6 superalloy in this *** effects of amplitude,frequency,spindle speed,and feed rate on thrust force,machining quality,and drill bit wear were studied;thereafter,a comparison was drawn between these effects and those of conventional drilling(CD).The experimental results reveal that the thrust force decreases with an increase in spindle speed or a decrease in feed rate for both UAD and *** can significantly reduce the thrust *** the same processing parameters,the greater the amplitude,the greater the reduction of the thrust *** surface roughness of the hole wall produced by UAD is lower than that of *** with CD,UAD reduces the burr height,improves machining accuracy,and reduces drill bit wear.

关键词： Ultrasonic assisted drilling(UAD) Thrust force Machining quality Drill bit wear

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密度对谷物混合颗粒分层影响的分析

农机化研究 2025年第4期47卷 35-41,49页

作者：张妍王子谦张延胡欣宇赵湛江苏大学农业工程学院江苏镇江212013

采用离散元模拟了垂直振动下具有相同尺寸、不同密度的谷物混合颗粒分层过程,结果表明:小密度颗粒倾向于向上运动形成单一颗粒层,而大密度颗粒与部分小密度颗粒停留在单一颗粒层下,组成混合状态。为此,提出相应评价指标,定量描述混合物... 详细信息

采用离散元模拟了垂直振动下具有相同尺寸、不同密度的谷物混合颗粒分层过程,结果表明:小密度颗粒倾向于向上运动形成单一颗粒层,而大密度颗粒与部分小密度颗粒停留在单一颗粒层下,组成混合状态。为此,提出相应评价指标,定量描述混合物分层程度,并讨论了混合颗粒密度比对分层速度的影响。结合混合物分层中空隙填充及动能理论,分析了密度影响分层机理,结果表明:在不同密度谷物混合颗粒分层过程中,随密度比增加小密度颗粒组成的单一颗粒层厚度增加并趋于饱和;混合层占总层数比率随密度比增加而减少并趋于稳定;颗粒分层速度随着密度比增加而增加,当密度比大于10时密度比对分层速度影响减弱;在混合物分层过程中,大密度颗粒较为活跃,且动能大于小密度颗粒的动能。

关键词：谷物颗粒分层密度数值模拟离散元法

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A new method of dynamic mesh used in continuous guide vane closure of a reversible pump-turbine in generating mode

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Journal of Hydrodynamics 2019年第5期31卷 976-985页

作者： xiu-li Mao Yuan Zheng Giorgio Pavesi zhan-shan Xie College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China Department of Industrial Engineering University of PaduaPadovaItaly

In this paper,a new method of dynamic mesh based on two functional controls is used in the continuous guide vane closure,and the three-dimensional numerical simulation is carried out to investigate the transient flow characteristics for a Francis-type reversible pump-turbine in the turbine mode in the load regulation scenario,with the detached eddy simulation(DES)turbulent *** transient flow characteristics during the closure of the guide vanes are illustrated by analyzing the signals of the mass flow,the torque and the pressure fluctuations in the frequency and time-frequency *** is shown by the simulated results that a continuous assessment of the transient flow characteristics during the guide vane closure may be made by using the new method of the dynamic ***,the flow field analysis involves both the onset and the development of the unsteady phenomena progressively based on an organized guide vane closure *** flow pattern in the return channel maintains a relatively stable flow field before the last stage of the closure,as compared with the unstable flow field in other *** identify the unit variation under the fluid-dynamical conditions,the influence of the three-dimensional unsteady flow structures in the passage is analyzed and its evolution during this transient process is characterized by the fluid-dynamics and the spectral analysis.

关键词： Francis-type reversible turbine dynamic mesh guide vane closure flow characteristics

Topology Optimization of Compliant Mechanisms with Geometrical Nonlinearities Using the Ground Structure Approach

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Chinese Journal of Mechanical Engineering 2011年第2期24卷 257-263页

作者： zhan Jinqing zhang Xianmin School of Mechanical and Automotive Engineering South China University of Technology Guangzhou 510640 China

The majority of topology optimization of compliant mechanisms uses linear finite element models to find the structure *** the displacements of compliant mechanisms are intrinsically large,the topological design can not provide quantitatively accurate ***,topological design of these mechanisms considering geometrical nonlinearities is essential.A new methodology for geometrical nonlinear topology optimization of compliant mechanisms under displacement loading is *** elements are chosen to represent the design domain because they are capable of capturing the bending *** nonlinear structural response is obtained by using the co-rotational total Lagrange finite element formulation,and the equilibrium is solved by using the incremental scheme combined with Newton-Raphson *** multi-objective function is developed by the minimum strain energy and maximum geometric advantage to design the mechanism which meets both stiffness and flexibility requirements, *** adjoint method and the direct differentiation method are applied to obtain the sensitivities of the objective functions. The method of moving asymptotes（MMA） is employed as *** numerical example is simulated to show that the optimal mechanism based on geometrically nonlinear formulation not only has more flexibility and stiffness than that based on linear formulation,but also has better stress distribution than the *** is necessary to design compliant mechanisms using geometrically nonlinear topology *** with linear formulation,the formulation for geometrically nonlinear topology optimization of compliant mechanisms can give the compliant mechanism that has better mechanical performance.A new method is provided for topological design of large displacement compliant mechanisms.

关键词： compliant mechanisms topology optimization geometrical nonlinearities the ground structure approach displacement loading

Complex SAR Image Compression Using Entropy-Constrained Dictionary Learning and Universal Trellis Coded Quantization

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Chinese Journal of Electronics 2016年第4期25卷 686-691页

作者： zhan Xin zhang Rong Department of Electronic Engineering and Information Science University of Science and Technology of China Key Laboratory of Electromagnetic Space Information Chinese Academy of Sciences

In this paper,an Entropy-constrained dictionary learning algorithm(ECDLA) is introduced for efficient compression of Synthetic aperture radar(SAR) complex *** RI encodes the Real and imaginary parts of the images using ECDLA and sparse representation,and ECDLA AP encodes the Amplitude and phase parts *** compared with the compression method based on the traditional Dictionary learning algorithm(DLA),ECDLA RI improves the Signal-to-noise ratio(SNR) up to 0.66 dB and reduces the Mean phase error(MPE) up to 0.0735 than DLA *** the same MPE,ECDLA AP outperforms DLA AP by up to 0.87 dB in ***,the proposed method is also suitable for real-time applications.

关键词： Synthetic aperture radar image compression Dictionary learning Sparse representation

Mechanical properties of a microalloyed bainitic steel after hot forging and tempering

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Journal of Iron and Steel Research International 2017年第11期24卷 1085-1094页

作者： Zhi-bao Xu Wei-jun Hui zhan-hua Wang Yong-jian zhang Xiao-li Zhao xiu-ming Zhao School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China z School of Materials Engineering Nanjing Institute of TechnologyNanjing 211167JiangsuChina

Mechanical properties of a newly developed microalloyed bainitic steel were investigated after the hot forging, air cooling and tempering process. The microstructure of the as forged bainitic steel mainly consists of granular bainite and -20 vol. % martensite. The fraction of retained austenite remains unchanged until tempering at 200 ℃, above which it decreases significantly. The increase of tempering temperature leads to decreases of both ultimate tensile strength and total elongation but decreases of both yield strength and reduction of area. The maximum and mini- mum values of impact toughness were observed after tempering at around 200 and 400 ℃, respectively. These effects are mainly attributed to the decomposition of martensite/austenite con stituents and the tempering effects in martensite. The tempering of the forged bainitic steel at around 200 ℃ results in an excellent combination of strength and toughness, which is comparable to that of the conventional quenched and-tempered 40Cr steel. Therefore, low-tempering treatment coupled with post-forging residual stress relieving is a feasible method to further improve the mechanical prooerties of the bainitic foging steel.

关键词： Bainitic forging steel Mechanical property Tempering Microstructure Granular bainite