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New insights into the regulation of Axin function in canonical Wnt signaling pathway

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Protein & Cell 2014年第3期5卷 186-193页

作者： Xiaomin Song Sheng wang lin li State Key Laboratory of Molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for BiologicalSciences Chinese Academy of Sciences Shanghai 200031 China

The Wnt signaling pathway plays crucial roles during embryonic development, whose aberration is implicated in a variety of human cancers. Axin, a key component of canonical Wnt pathway, plays dual roles in modulat- ing Wnt signaling： on one hand, Axin scaffolds the ＂l^-catenin destruction complex＂ to promote 13-catenin degradation and therefore inhibits the Wnt signal transduction; on the other hand, Axin interacts with LRP5/6 and facilitates the recruitment of GSK3 to the plasma membrane to promote LRP516 phosphorylation and Wnt signaling. The differential assemblies of Axin with these two distinct complexes have to be tightly controlled for appropriate transduction of the ＂on＂ or ＂off＂ Wnt signal. So far, there are multiple mechanisms revealed in the regulation of Axin activity, such as post- transcriptional modulation, homo/hetero-polymerization and auto-inhibition. These mechanisms may work cooperatively to modulate the function of Axin, thereby playing an important role in controlling the canonical Wnt signaling. In this review, we will focus on the recent progresses regarding the regulation of Axin function in canonical Wnt signaling.

关键词： Wnt signaling Axin post-transcriptionalmodification polymerization auto-inhibition

Thiol-functionalized MCM-48: an Effective Absorbent of Mercury Ions

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Chinese Chemical Letters 2006年第2期17卷 221-224页

作者： Shu Guo wang Jin lin li Key Laboratory for Catalysis and Material Science of Hubei Province College of Chemistry and Material Sciences South-Central University for Nationalities Wuhan 430074

Mercaptopropyl groups were grafted onto the pore walls of mesoporous molecular sieves MCM-48. The pore structures were characterized by powder X-ray diffraction and N2 adsorption analYSiS. Elemental analysis confirmed that the material with high organic moiety （2.2 mmol/g） had been obtained. ^13C MAS NMR verified the tethered organic groups. The thiol-functionalized MCM-48 showed effective capture of mercury ions, and all of the organic ligands were accessible for the binding of mercury ions.

关键词： Mercaptopropyl MCM-48 absorbent mercury ions.

Development of Near Infrared Spectroscopy for Rapid Quality Assessment of Red Ginseng

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Chemical Research in Chinese Universities 2009年第5期25卷 633-637页

作者： NIE li-xing wang Gang-li lin Rui-chao National Institute for the Control of Pharmaceutical and Biological Products Beijing 100050 P. R. China

Near infrared spectroscopy（NIRS） was developed as a rapid analysis method for the qualitative and quantitative assessment of the quality of red ginseng. Discriminant analysis（DA） based on principal component analysis and Mahalanobis distance was used to distinguish red ginseng from counterfeits non-destructively. The result shows that the proposed method could distinguish red ginseng from counterfeits correctly and no misclassified sample was found in both training and test sets. The partial least squares（PLS） algorithm was used to predict the sum of ginsenosides Re and Rgl and the content of ginsenoside Rb1. Two calibration models were developed to correlate NIR spectra with the reference values determined by HPLC method. The correlation coefficient（R）, the root mean square error of calibration（RMSEC） and the root mean square error of prediction（RMSEP） were as follows： R=0.9827, RMSEC=0.0163%, RMSEP=0.0250% for the sum of ginsenosides Re and Rgl; R=0.9869, RMSEC=0.0156%, RMSEP=0.0256% for content of ginsenoside Rb1. The overall results demonstrate that NIRS coupled with chemometrics could be successfully applied as a rapid, precise and cost-effective method not only to identify the red ginseng from counterfeits but also to determine simultaneously some chemical compositions in red ginseng.

关键词： Near infrared soectroscopy Red ginseng Discriminant analysis Partial least squares

Occurrence and removal of N-nitrosodimethylamine and its precursors in wastewater treatment plants in and around Shanghai

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Frontiers of Environmental Science & Engineering 2014年第4期8卷 519-530页

作者： lin wang Yongmei li Xiaoling SHANG Jing SHEN State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China

Six wastewater treatment plants （WWTPs） were investigated to evaluate the occurrence and removal of N-nitrosodimethylamine （NDMA）, NDMA formation potential （FP） and four specific NDMA precursors, dimethylamine （DMA）, trimethylamine （TMA）, dimethyl- formamide （DMFA） and dimethylaminobenzene （DMAB）. DMA and tertiary amines with DMA functional group commonly existed in municipal wastewater. Chemically enhanced primary process （CEPP） had no effect on removal of either NDMA or NDMA FP. In WWTPs with secondary treatment processes, considerable variability was observed in the removal of NDMA （19%-85%） and NDMA FP （16%-76%）, moreover, there was no definite relationship between the removal of NDMA and NDMA FP. DMA was well removed in all the six surveyed WWTPs; its removal efficiency was greater than 97%. For the removal of tertiary amines, biologic treatment processes with nitrification and denitrification had better removal efficiency than conventional activated sludge process. The best removal efficiencies for TMA, DMFA and DMAB were 95%, 68% and 72%, respectively. CEPP could remove 73% of TMA, 23% of DMFA and 36% of DMAB. After UV disinfection, only 17% of NDMA was removed due to low dosage of UV was applied in WWTP. Although chlorination could reduce NDMA precursors, NDMA concentration was actually increased after chlorination.

关键词： N-nitrosodimethylamine NDMA precursors NDMA formation potential biological treatment process chemically enhanced primary process

Fabrication of 2D ZnO Nanosheet Thin Film by a Simple Two-Step Approach

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稀有金属材料与工程 2006年第A03期35卷 642-643页

作者： Ning wang Hong lin Jianbao li Xiaozhan Yang Jun Yang Chunfu lin State Key Lab of New Ceramics ＆ Fine Processing Department of Materials Science ＆ Engineering Tsinghua University Beijing 100084 China

In this paper,2D single-crystalline ZnO nanosheets thin film was fabricated successfully on silicon wafer by a simple two-step ***,SEM and TEM were used to characterize the phase structures and morphologies of ZnO nan... 详细信息

关键词： ZnO nanosheets crystal growth thin film

Preparation of Anhydrous LnCl_3(Ln=Eu, Er, Lu) by Chemical Vapor Transport

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Journal of Rare Earths 2000年第2期18卷 152-154页

作者： wang lin shan, li Ying, wang Yu hong (Department of Chemistry, Northeastern University, Shenyang 110006, China) Northeastern Univ Dept Chem Shenyang 110006 Peoples R China

Anhydrous lanthanide chlorides LnCl 3(Ln=Eu, Er, Lu) which are not easy to prepare in other ways were prepared by chemical vapor transport(CVT) method. Ln 2O 3 reacted with an excess of Al 2Cl 6 at 300 ℃ to produce LnCl 3. LnCl 3 reacted with Al 2Cl 6 at high temperature to form the gaseous complexes which decomposed at low temperature. LnCl 3 was then separated from other solids by controlling a proper temperature gradient. Residual Al 2Cl 6(g) was removed by the carrier of dry Cl 2 N 2 gases at 200 ℃. The yield rates are >90%, and the purity of products is >99 5%. The high purity of anhydrous lanthanide chlorides can be obtained by CVT method.

关键词： rare earths preparation chemical vapor transport

Prediction and Analysis on Oxidation of H13 Hot Work Steel

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Journal of Iron and Steel Research International 2006年第1期13卷 44-49页

作者： MIN Yong-an WU Xiao-chun wang Rong li lin XU Luo-ping School of Materials Science and Engineering Shanghai University Shanghai 200072 China

The understanding of oxidation behaviors on H13 steel was helpful to improve the service life and performance of hot work moulds and dies. Thermal-Calc Software was performed to calculate the oxidation phases on H13 steel along with different partial oxygen pressures in the interesting temperature range of 500-700 ℃. In this range H13 steel samples were treated respectively in different atmosphere including flowing water vapor （0.2 MPa）, normal pressure air （0.1 MPa） and low pressure air （0. 001 MPa）. The different oxidation films were detected with optical microscopy and X-ray diffraction. The microstructures and phase constitutions of the films formed in low pressure air were similar to those of the films formed in water vapor, and obviously different to those of the films formed in normal pressure air. The oxidation mechanisms of H13 steel in different atmosphere were also discussed.

关键词： oxidatiom hot work steel surface treatment die casting

Electron-electron interactions in monolayer graphene quantum capacitors

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Nano Research 2013年第8期6卷 619-626页

作者： Xiaolong Chen lin wang Wei li Yang wang Zefei Wu Mingwei Zhang Yu Han Yuheng He Ning wang Department of Physics and the William Mong Institute of Nano Science and Technology Hong Kong University of Science andTechnology Hong Kong S.A.R. China

We demonstrate the effects of electron-electron （e-e） interactions in monolayer graphene quantum capacitors. Ultrathin yttrium oxide showed excellent per-formance as the dielectric layer in top-gate device geometry. The structure and dielectric constant of the yttrium oxide layers have been carefully studied. The inverse compressibility retrieved from the quantum capacitance agreed fairly well with the theoretical predictions for the e--e interactions in monolayer graphene at different temperatures. We found that electron-hole puddles played a significant role in the low-density carrier region in graphene. By considering the temperature-dependent charge fluctuation, we established a model to explain the round-off effect originating from the e-e interactions in monolayer graphene near the Dirac point.

关键词： graphene e-e interaction inverse compressibility quantum capacitance charge fluctuation electron-hole puddles

Continuous Cooling Transformation Behavior and Kinetic Models of Transformations for an Ultra-Low Carbon Bainitic Steel

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Journal of Iron and Steel Research International 2012年第12期19卷 73-78页

作者： ZHANG Zhi-min CAI Qing-wu YU Wei liXiao-lin wang li-dong Metallurgical Engineering Research Institute University of Science and Technology Beijing Beijing 100083 China

The aim was to investigate transformation behavior and transformation kinetics of an ultra-low carbon bai- nitic steel during continuous cooling. Continuous cooling transformation （CCT） curves of tested steel were measured by thermal dilatometer and metallographic structures at room temperature were observed by optical microscope. Then transformation kinetic equation of austenite to ferrite as well as austenite to bainite was established by analyzing the relationship of lnln]-l/（1--f）] and lnt in the kinetic equation on the basis of processed experimental data. Finally, the measured and calculated kinetic behaviors of the steel during continuous cooling were compared and growth pat- terns of transformed ferrite and bainite were analyzed. Results showed that calculated result was in reasonable agree- ment with the experimental data. It could be concluded that the growth modes of transformed ferrite and bainite were mainly one dimension as the Avrami exponents were between 1 and 2.

关键词： ultra low carbon bainitic steel continuous cooling transformation kinetics Avrami equation