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Activity and Tissue Expression of Tyrosine Phosphatase PTP-MEG2

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Chemical Research in Chinese Universities 2011年第2期27卷 287-290页

作者： dong hong-bo LI Guo-dong WANG Shao-feng FU Xue-qi ZHAO Zhi-zhuang Joe Edmond H. Fischer Signal Transduction Laboratory College of Life Science Jilin University Changchun 130012 P. R. China School of Pharmaceutical Science Jilin University Changchun 130021 P. R. China The Second Hospital of Jilin University. Changchun 130041 P. R. China Department of Pathology University of Oklahoma Health Sciences Center Oklahoma City Oklahoma 73104 USA

Protein tyrosine phosphatases（PTPs） are crucial regulators of signal transduction. Among them, PTP-MEG2 is an intracellular enzyme of 593 amino acid residues with a putative lipid-binding domain at the N-terminus. In the present study, we cloned the full-length form of the enzyme and expressed it in E. coli cells as a 6xHis-tagged protein. The majority of the expressed enzyme was found in the inclusion body of E. coli cell extracts. Upon extraction with a buffer containing urea, the recombinant enzyme was purified to near homogeneity on a single Ni-NTA-agarose column. This procedure resulted in the production of over 100 mg of purified recombinant PTP-MEG2 from 1 L E. coli cell culture. The purified protein displayed a single polypeptide band with expected molecular size on SDS-polyacrylamide gel electrophoresis under reducing conditions. Isolated under denatured conditions in urea, the purified enzyme was re-natured by dialyzing against a refolding buffer. The re-natured enzyme effectively dephosphorylated the common PTP substrate para-nitrophenylphosphate with a specific activity of 2000 units/mg. Meanwhile, the denatured enzyme was used to immunize a rabbit to produce antibodies. The resulting anti- serum had extremely high sensitivity and specificity. When used for Western blot analysis, the anti-serum revealed a wide expression of PTP-MEG2 in many tissues of mice. Together, we developed a highly effective way to purify a large amount of PTP-MEG2 and generated highly sensitive antibodies that can specifically detect endogenous expression of the enzyme in tissues.

关键词： Protein tyrosine phosphatase Expression Antibody production Enzyme assay Tissue expression

Effect of temperature on formation and evolution of solid electrolyte in terphase on Si@Graphite@C anodes

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Journal of Energy Chemistry 2022年第1期31卷 190-200,I0006页

作者： hong dong Jie Wang Peng Wang Hao Ding Ru Song Ning-Shuang Zhang dong-Ni Zhao Li-Juan Zhang Shi-You Li College of Petrochemical Technology Lanzhou University of TechnologyLanzhou 730050GansuChina Gansu Key Laboratory of Low-Carbon Energy and Chemical Engineering Lanzhou 730050GansuChina College of Chemistry and Chemical Engineering Qinghai University for NationalitiesXining 810007QinghaiChina

Studies on the formati on and evolutio n of the solid electrolyte in terface(SEI)film under different ambient temperatures are important to understand the failure behavior of lithium-ion batteries(LIBs).Herein,in-situ electrochemical impedance spectroscopy(EIS)test is performed on the whole discharge process of Si@Graphite@C/Li cell at 0,25 and 55℃,*** with scanning electron microscopy,transmission electron microscopy and X-ray photoelectron spectroscopy characterizations,it is found that the SEI film undergoes a complicated evolution process of pre-formation,self-improvement and gradual decay in succession at 25℃.Besides,due to the dissolution of organo-alkyl lithium at high temperature,the formed film is mainly composed of LiF,Li_(2)CO_(3) and other in organic salts,which helps to decrease the ***,the electrolyte is consumed continuously on the new exposed in terface,leading to the degraded performance of the ***,the dyn amic properties of Li^(+) ions are poor at low temperature,though the migration ability of Li^(+) ions in the solid phase can be improved as the cycle goes ***,the development and application of in-situ EIS tech no logy are expected to become an important means to explain the electrochemical performance of batteries.

关键词： In-situ EIS Solid electrolyte in terphase Formation Evolution Si@Graphite@C anodes

An efficient parallel algorithm for DNS of buoyancy-driven turbulent flows

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Journal of Hydrodynamics 2019年第6期31卷 1159-1169页

作者： Yi-zhao Zhang Shu-ning Xia Yu-hong dong Bo-fu Wang Quan Zhou Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China

In this paper,an explicit low-storage simplified M-stage Runge-Kutta(SRK)scheme for high Reynolds-number incompressible flows is *** the SRK scheme,the Poisson equation is solved only once in the final substage of each time *** taking advantage of the SRK scheme and the advanced hybrid MPI+MPI model,we have developed an efficient parallel solver for buoyancy-driven turbulent *** spatial and temporal accuracies of the solver are validated with Taylor-Green vortex *** the RK and SRK schemes are implemented for the simulation of turbulent Rayleigh-Benard convection as well as Rayleigh-Taylor *** results show that the SRK scheme can save approximately 20%of the computation time.

关键词： Direct numerical simulation(DNS) parallel algorithm turbulent flows

Comprehensive recovery of Fe,Zn,Ag and In from high iron-bearing zinc calcine

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Journal of Central South University 2017年第5期24卷 1082-1089页

作者： PENG Bing PENG Ning LIU Hui XUE Ke LIN dong-hong Institute of Environmental Science and Engineering School of Metallurgical Science and EngineeringCentral South UniversityChangsha 410083China Chinese National Engineering Research Centre for Control&Treatment of Heavy Metal Pollution Changsha 410083China

A beneficiation-metallurgy combination process is developed to recover Zn, Fe and to enrich In, Ag from high iron-bearing zinc calcine based on our former researches. In gaseous reductive roasting process, the roasting conditions were tested by magnetic separation of roasted product. It is found that the V_(CO)(P_(CO)/(P_(CO+CO_2)) in roasting atmosphere should be maintained below 30% to avoid the generation of zinc iron solid solution(Fe_(0.85-x)Zn_xO), which can bring a decrease of iron recovery in magnetic separation. After roasting, acid leaching and multistage magnetic separation are carried out for the recovery of Zn, Fe and enrichment of Ag and In. About 90% of zinc is extracted and 83% of iron is recovered in the whole process. The Ag mainly enters the tailings with a recovery of 76%, the Ag grade increases from 0.12 g/t in raw materials to 1.18 g/t in the tailings. However, the In mainly enters the iron concentrations and the recovery reaches 86%. This process was proved to be technically feasible and may be a favorable option in the treatment of high iron-bearing zinc material with high Ag or In content.

关键词： high iron-bearing zinc calcine reductive roasting multistage magnetic separation silver recovery indium recovery

^137Cs tracing dynamics of soil erosion,organic carbon,and total nitrogen in terraced fields and forestland in the Middle Mountains of Nepal

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Journal of Mountain Science 2016年第10期13卷 1829-1839页

作者： SU Zheng-an XIONG dong-hong DENG Wei dong Yi-fan MA Jing PADMA C Poudel GURUNG B Sher Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Science Belting 100049China College of Water Conservancy and Hydropower Engineering Sichuan Agricultural UniversityYa'an 625014China Central Department of Geography University CampusTribhuvan UniversityKirtipur 8212Nepal

The Middle Mountains is one of the regions of Nepal most vulnerable to water erosion, where fragile geology, steep topography, anomalous climatic conditions, and intensive human activity have resulted in serious soil erosion and enhanced land degradation. Based on the 137 Cs tracing method, spatial variations in soil erosion, organic carbon, and total nitrogen(TN) in terraced fields lacking field banks and forestland were determined. Soil samples were collected at approximately 5 m and 20 m intervals along terraced field series and forestland transects respectively. Mean 137 Cs inventories of the four soil cores from the reference site was estimated at 574.33 ± 126.22 Bq m-2(1 Bq(i.e., one Becquerel) is equal to 1 disintegration per second(1 dps)). For each terrace, the 137 Cs inventory generally increased fromupper to lower slope positions, accompanied by a decrease in the soil erosion rate. Along the entire terraced toposequence, 137 Cs data showed that abrupt changes in soil erosion rates could occur between the lower part of the upper terrace and the upper part of the immediate terrace within a small distance. This result indicated that tillage erosion is also a dominant erosion type in the sloping farmland of this area. At the same time, we observed a fluctuant decrease in soil erosion rates for the whole terraced toposequence as well as a net deposition at the toe terrace. Although steep terraces(lacking banks and hedgerows) to some extent could act to limit soil sediment accumulation in catchments, soil erosion in the terraced field was determined to be serious. For forestland, with the exception of serious soil erosion that had taken place at the top of slopes due to concentrated flows from a country road situated above the forestland site, spatialvariation in soil erosion was similar to the "standard" water erosion model. Soil organic carbon(SOC) and TN inventories showed similar spatial patterns to the 137 Cs inventory for both toposequences investigated.

关键词： Nepal 137Cs inventory Soil erosion/deposition Soil organic carbon Total nitrogen

Growth Rate,Microstructure and Phase Composition of Oxide Scales for Three Typical Steels in Simulated Continuous Casting Process

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Journal of Iron and Steel Research International 2014年第12期21卷 1065-1072页

作者： Nan WANG Jian-hong dong Wei-jun HUANG Bo LI Min CHEN School of Materials and Metallurgy Northeastern University

C-rowth rate, microstructure and phase composition of scale layer formed during oxidation in 56 % H2O9%O2 N2 and following continuous cooling in ambient air were experimentally investigated by means of optical microscopy, scanning electron microscopy （SEM）, energy-dispersive spectroscopy （EDS） and X-ray diffraction （XRD） for 45, 20CrMnTi and TTS443M steels respectively, to examine the effects of strand surface temperature and steel composition on the scale formation in simulated continudus casting process. The growth rates were found to be ap proximately parabolic and the calculated activation energy of TTS443M steel is much higher than those of the two other steels. For 45 and 20CrMnTi steels, the scale layers were looser and a distinct gap formed at the scale-sub strate interface at higher strand surface temperature. The dominant phases within the scale were iron oxides except for FeO · Cr2O3 phase simuhaneously existing in the oxide scale of 20CrMnTi steel. On the other hand, the scale layer formed on TTS443M steel was compact and tightly attached to the steel surface. At both lower and higher strand surface temperature, iron oxide was main phase in external layer of the scale, while chromia was dominant in inner layer with an appreciable Cr enrichment.

关键词： oxide scale growth rate microstructure phase composition continuous casting

Application of principal component-radial basis function neural networks (PC-RBFNN) for the detection of water-adulterated bayberry juice by near-infrared spectroscopy

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第12期9卷 982-989页

作者： Li-juan XIE Xing-qian YE dong-hong LIU Yi-bin YING College of Biosystems Engineering and Food Science Zhejiang University Hangzhou 310029 China

Near-infrared (NIR) spectroscopy combined with chemometrics techniques was used to classify the pure bayberry juice and the one adulterated with 10% (w/w) and 20% (w/w) water. Principal component analysis (PCA) was applied to reduce the dimensions of spectral data, give information regarding a potential capability of separation of objects, and provide principal component (PC) scores for radial basis function neural networks (RBFNN). RBFNN was used to detect bayberry juice adulterant. Multiplicative scatter correction (MSC) and standard normal variate (SNV) transformation were used to preprocess spectra. The results demonstrate that PC-RBFNN with optimum parameters can separate pure bayberry juice samples from water-adulterated bayberry at a recognition rate of 97.62%, but cannot clearly detect water levels in the adulterated bayberry juice. We conclude that NIR technology can be successfully applied to detect water-adulterated bayberry juice.

关键词： Near-infrared (NIR) spectroscopy Principal component-radial basis function neural networks (PC-RBFNN) Bayberry juice Adulteration Chemometrics technique

Histological and Ultrastructural Observation Reveals Significant Cellular Differences between Agrobacterium Transformed Embryogenic and Non-embryogenic Calli of Cotton

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Journal of Integrative Plant Biology 2009年第5期51卷 456-465页

作者： Hai-hong Shang Chuan-Liang Liu Chao-Jun Zhang Feng-Lian Li Wei-dong hong Fu-Guang Li Key Laboratory of Cotton Genetic Improvement Ministry of Agriculture Chinese Cotton Research Institute Chinese Agricultural Academy of Sciences Anyang 455004 China

Over the past few decades genetic engineering has been applied to improve cotton breeding. Agrobacterium medicated transformation is nowadays widely used as an efficient approach to introduce exogenous genes into cotton for genetically modified organisms. However, it still needs to be improved for better transformation efficiency and higher embryogenic callus induction ratios. To research further the difference of mechanisms for morphogenesis between embryogenic callus and non-embryogenic callus, we carried out a systematical study on the histological and cellular ultrastructure of Agrobacterium transformed calli. Results showed that the embryogenic callus developed nodule-like structures, which were formed by small, tightly packed, hemispherical cells. The surface of some embryogenic callus was covered with a fibrilar-like structure named extracellular matrix. The cells of embryogenic calli had similar morphological characteristics. Organelles of embryogenic callus cells were located near the nucleus, and chloroplasts degraded to proplastid-like structures with some starch grains. In contrast, the non-embryogenic calli were covered by oval or sphere cells or small clusters of cells. It was observed that cells had vacuolation of cytoplasm and plastids with a well organized endomembrane system. This study aims to understand the mechanisms of embryogenic callus morphogenesis and to improve the efficiency of cotton transformation in future.

关键词： cell organization pattern chloroplasts embryogenic callus Gossypiurn hirsutum histological structure transformation ultrastructure

A Critical Review on Superchilling Preservation Technology in Aquatic Product

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Journal of Integrative Agriculture 2014年第12期13卷 2788-2806页

作者： WU Chun-hua YUAN Chun-hong YE Xing-qian HU Ya-qin CHEN Shi-guo LIU dong-hong Department of Food Science and Nutrition Zhejiang Key Laboratory for Agro-Food Processing Fuli Institute of Food Science Zhejiang University Faculty of Fisheries Kagoshima University

aquatic product, known as one of the good resources for white meat, has been widely accepted by the consumers due to its high protein, low fat, especially low cholesterol. With the fast development of living standards around the world, the consumer demands for high quality, nutrition, safety and freshness of ifshery food are increasing. Thus, high efifcient preservation technologies for aquatic products become particularly important. Superchilling is one of the controlled-temperature preservation technologies for seafood. Aquatic products can be kept in better quality under superchilling conditions. This review introduced the principle and development of superchilling process, mainly focusing on research progresses and technical dififculties of superchilling. The growth mechanism of ice crystals and the feasibility of application of computational lfuid dynamics in analyzing the temperatures variation and ice crystals during superchilling progress were also discussed, which will provide theoretical foundation for its improvement and application.

关键词： aquatic product superchilling freshness growth mechanism of ice crystals computational lfuid dynamics