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K-Theory and the Quantization Commutes with Reduction Problem

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Chinese Annals of Mathematics,Series B 2014年第5期35卷 703-732页

作者： Nigel HIGSON yanli song Department of Mathematics Pennsylvania State University University Park Department of Mathematics University of TorontoRoom 6290 40 St. George Street Toronto OntarioCanada M5S2E4

The authors examine the quantization commutes with reduction phenomenon for Hamiltonian actions of compact Lie groups on closed symplectic manifolds from the point of view of topological K-theory and K-homology. They develop the machinery of K-theory wrong-way maps in the context of orbifolds and use it to relate the quantization commutes with reduction phenomenon to Bott periodicity and the K-theory formulation of the Weyl character formula.

关键词： Symplectic reduction Quantization K-Theory K-Homology CompactLie groups

Hydrogen peroxide homeostasis and signaling in plant cells

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Science China(Life Sciences) 2006年第1期49卷 1-11页

作者： CHENG yanli song Chunpen Laboratoryof Plant Stress Biology Department of Biology Henan University Kaifeng 475001 China Laboratoryof Plant Stress Biology Department of Biology Henan University Kaifeng 475001 China

The increases of H2O2 concentrations in plant cells often occur under biotic and abiotic stress conditions (e.g. light, environmental stresses and plant hormone abscisic acid). Atmospheric H2O2 as an ancient signal molecule not only plays the key role in inducing evolution of oxygenic photosynthesis, but also modulates many physiological events, such as stomatal movement, hypersensitive responses, programmed cell death and gene expressions. H2O2 levels in cells must sustain a fine equilibrium between production and scavenging. H2O2 enters cells from the apoplast or generated sources, and in turn is distributed in sub-cellular compartments. H2O2 can modulate the activities of many components in signaling, such as protein phosphatases, protein kinases, transcription factors (TFs), and calcium channels. Elevated cytosolic calcium concentrations will initiate further downstream responses, via the action of calcium-binding proteins. On the other hand, the research of H2O2 as a signal molecule is still in a comparatively juvenile stage, for example, little is known about how the cells sense H2O2, what the rate-limiting steps and most important cellular events are in cell signaling and what kind of genes is specific or necessary to H2O2 signaling. The answers to all the questions depend on the functional genomic and molecular genetics analysis.

关键词： H2O2, signal transduction, abscisic acid, environmental stresses, gene expression, apoptosis.

Effects of Electric and Magnetic Treatments on Microstructures of Solid Metals: A Review

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Chinese Journal of Mechanical Engineering 2023年第6期36卷 1-21页

作者： yanli song Wenlin Wu Yongqing Yu Lin Hua Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of TechnologyWuhan 430070China School of Automotive Engineering Wuhan University of TechnologyWuhan 430070China Hubei Research Center for New Energy&Intelligent Connected Vehicle Wuhan University of TechnologyWuhan 430070China

An external electric or magnetic field can transfer high-intensity energy directly to the electronic scale of materials,and change the spin,energy level arrangement and trajectory of *** changes produce tremendous and profound impacts on the microstructure and mechanical properties of metal materials,which may be impos-sible with traditional *** paper reviews the effects of electric or magnetic field on the microstruc-tures of solid metals including phase transformation,precipitation,recrystallization,dislocations and so *** on the existing research results,the mechanisms of these effects have been ***,some typical applications of electric and magnetic treatments on solid metals have been described and the challenges in this field have also been discussed.

关键词： Electric field Magnetic field Microstructures Mechanical properties Solid metals

Strain rate sensitivity of tensile properties in high Nb containing TiAl alloys

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Journal of University of Science and Technology Beijing 2005年第6期12卷 535-539页

作者： Jianfeng Gao Xiangjun Xu Junpin Lin Xiping song yanli Wang Guoliang Chen State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

The effect of strain rate on the yield strength of high Nb containing TiAl alloy was studied. The results show that the strain rate sensitivity varies with the test temperature, and the yield strength is not sensitive to the strain rate at room temperature but significantly sensitive to the strain rate at high temperature. An increase of the strain rate or a decrease of the temperature results in an obvious change of fracture mode. It is found that the strain rate sensitivity of this alloy varying with temperature is due to the dislocation climb generated at high temperature.

关键词： TiAl alloys strain rate tensile properties thermal activation

Reduction of Residual Stress in Low Alloy Steel with Magnetic Treatment in Different Directions

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Journal of Wuhan University of Technology(Materials Science) 2009年第6期24卷 857-862页

作者：宋燕利华林 School of Materials Science and Engineering Wuhan University of Technology

The behavior that different magnetic treatment directions induce various amounts of welding residual stress reductions in low alloy steel was studied. Reductions of 26%-28% in the longitudinal stress σ x were obtained when low frequency alternating magnetic treatment was applied perpendicularly to the welding bead, whereas reductions of 20%-21% in σ x were measured by using the same treatment parameters except that the field direction was applied parallel to the bead. It is proposed that different extent of stress reductions caused by the above two treatment directions is attributed primarily to the alteration of the energy absorbed by domains from the external magnetic field, which part of energy can arouse plastic deformation in microstructures by the motion of domain walls.

关键词： magnetic treatment direction magnetic domain residual stress spontaneous magnetization micro plastic deformation

Investigation of the Effect of Neoadjuvant Chemotherapy on Stage Ⅱ Breast Cancer

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Chinese Journal of Clinical Oncology 2007年第2期4卷 142-144页

作者： yanli song Dong Wang Department of General Surgery Dalian No. 3 People＇s Hospital Dalian 116033 China

OBJECTIVE To investigate the effect of neoadjuvant chemotherapy in treatment of Stage Ⅱ breast cancer. METHODS The data from 113 patients with breast cancer of the same pathologic type in Stage Ⅱ,during the period of 1995 to 2001,were analyzed *** the patients,47 were treated with neoadjuvant chemotherapy,and 66 received no adjuvant therapy before surgery（control group）.After the patients of the neoadjuvant chemotherapy group had received 2 courses of chemotherapy with the CMF regimen,the surgical procedure was conducted. RESULTS Complete remission（CR）was attained in 9 of the 47 cases receiving neoadjuvant chemotherapy and partial remission（PR）was reached for 22 *** rate of breast-conserving surgery was enhanced from 22.73%to 46.81%（P〈0.05）in the neoadjuvant treatment group. There was no difference in the 5-year overall survival（OS）and disease-free survival（DFS）rate between the two groups（P〉0.05）,but the 5-year OS and DFS of the cases with clinical tumor remission was higher compared to the control group（P〈0.05）. CONCLUSION Neoadjuvant chemotherapy can enhance the rate of breast conservation for Stage Ⅱ breast cancer and may improve the prognosis of the cases with clinical remission.

关键词： breast cancer neoadjuvant chemotherapy five-year survival rate.

旋轨耦合从头算方法研究CH2BrI光解离机理

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高等学校化学学报 2015年第11期36卷 2163-2170页

作者：宋艳丽刘亚军理论及计算光化学教育部重点实验室北京师范大学化学学院北京100085

基于CH2Br I光解离的最新实验报道,采用多态完全活化空间二阶微扰理论和完全活化空间态相互作用-旋轨耦合作用(MS-CASPT2/CASSI-SO)方法,计算了CH2Br I在乙腈、2-丁醇和环己烷3种溶剂中,在266nm的光激发下的旋轨耦合态的势能曲线,指认... 详细信息

基于CH2Br I光解离的最新实验报道,采用多态完全活化空间二阶微扰理论和完全活化空间态相互作用-旋轨耦合作用(MS-CASPT2/CASSI-SO)方法,计算了CH2Br I在乙腈、2-丁醇和环己烷3种溶剂中,在266nm的光激发下的旋轨耦合态的势能曲线,指认了实验观测到的解离产物I(2P3/2)和I*(2P1/2)的具体解离途径.为了理解不同溶剂对光产物重新结合成CH2Br—I和CH2I—Br的影响,对CH2Br I在溶剂中光异构化过程的反应机理进行了探讨.

关键词：溴碘甲烷光解离溶剂化效应完全活化空间二阶微扰旋轨耦合从头算

Characterization of cancer stem-like cells in a novel STI571-resistant chronic myeloid leukemia cell line

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The Chinese-German Journal of Clinical Oncology 2007年第4期6卷 383-388页

作者： Baijun Fang Yongping song yanli Zhang Quande Lin Xudong Wei Henan Tumor Hospital Henan Institute of Haematology Henan Medical School Henan University Zhengzhou450008 China

Objective： To characterize a novel chronic myeloid leukemia （CML） cell line and to further elucidate the mechanisms of resistance to STI571. Methods： A novel K562 cell line （K562NP16） was achieved after exposure of the K562 cells to VP16. A small subpopulation （K562NP16 SP） that was capable of excluding Hoechst 33342 in the K562NP16 cell line was isolated by fiow cytometry sorting. The rest of the K562NP16 cells were classified as non-SP K562NP16. The mechanisms involved in K562NP16 SP cells which became resistant to STI571 were studied. Results： The levels of Bcr-Abl and Abl proteins were similar in the K562 cell line and in non-SP K562NP16 and K562NP16 SP cells. The multidrug-resistant gene 1 （MDR1） expression of the 170 kDa P-glycoprotein （P-gp） was detected in K562NP16 non-SP and K562NP16 SP cells but not in K562 cells. The expression levels of P-gp in the two K562NP16 cell lines were similar. Compared with non-SP K562/ VP16, the K562NP16 SP cells were more resistant to STI571. This resistance could hardly be reversed by many multidrug resistance inhibitors. In addition, in vivo study showed that the K562NP16 SP cells induced tumorigenesis in mice, while the K562NP16 non-SP cells failed to do so. Conclusion： A novel K562 cell line, K562NP16, was generated. A small side population K562NP16 SP cells, had high resistance to STI571 treatment and more tumorigenic than the K562 cells. It may represent the cancer stem cells of the K562NP16 cell line.

关键词： K562 cancer stem cell side population multidrug resistance

面向汽车轻量化应用的碳纤维复合材料关键技术

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材料导报 2016年第17期30卷 16-25,50页

作者：宋燕利杨龙郭巍华林武汉理工大学现代汽车零部件技术湖北省重点实验室武汉430070 武汉理工大学汽车零部件技术湖北省协同创新中心武汉430070

轻量化技术已成为汽车实现节能、减排的重要途径,碳纤维复合材料为汽车轻量化提供了重要材料基础。由于材料特性与制造工艺的特殊性与复杂性,采用碳纤维复合材料实现汽车轻量化时需要克服多项关键技术。结合汽车产品特点,从低成本碳纤... 详细信息

轻量化技术已成为汽车实现节能、减排的重要途径,碳纤维复合材料为汽车轻量化提供了重要材料基础。由于材料特性与制造工艺的特殊性与复杂性,采用碳纤维复合材料实现汽车轻量化时需要克服多项关键技术。结合汽车产品特点,从低成本碳纤维技术、材料-结构-性能一体化技术、高效成型技术、多材料连接技术、循环利用技术几个方面阐述了碳纤维复合材料在汽车轻量化应用中的关键技术,展望了未来汽车用碳纤维复合材料的发展趋势。

关键词：汽车轻量化碳纤维复合材料低成本碳纤维高效成型多材料连接