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science china Chemistry 2010年第3期53卷 618-624页

作者： LIU JiangTao1,LIU ShaoPu2 & LIU ZhongFang2 1school of Chemistry,Chongqing normal University,Chongqing 400300,china 2school of Chemistry and Chemical Engineering,Southwest University,Chongqing 400715,china school of Chemistry Chongqing Normal University Chongqing China school of Chemistry and Chemical Engineering Southwest University Chongqing China

The forming of bleomycinA2-Cu(Ⅱ) cationic chelate and the interaction of the chelate with DNA have been investigated by using resonance Rayleigh scattering(RRS),molecular absorption and fluorescence *** result shows that in aqueous solution,bleomycinA2(BLMA2) can react with Cu(Ⅱ) to form 1:1 cationic chelate which contributes to the changes of the absorption spectra and the quenched fluorescence of *** the cationic chelate further bound with DNA to form ternary ion-association complexes,the remarkable enhancement of the RRS intensity was *** this work,the optimum conditions for the coordination reaction of BLMA2 with Cu(Ⅱ) and some influencing factors have been *** reaction mechanism of BLMA2-Cu(Ⅱ) binding with DNA was suggested and a binding model was *** addition,the fluorescence quenching type of BLMA2 was investigated.A highly sensitive,simple and rapid new method for the determination of DNA by using BLMA2-Cu(Ⅱ) as RRS probe has been *** detection limits(3σ) are 7.2 ng/mL for ctDNA,7.1 ng/mL for sDNA and 18 ng/mL for *** method can be applied to the determination of trace amounts of DNA.

关键词： bleomycinA2 Cu(Ⅱ) DNA resonance Rayleigh scattering fluorescence quenching

Two new Jurassic stoneflies (Insecta: Plecoptera) from Daohugou, Inner Mongolia, china

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Progress in Natural science:Materials International 2008年第8期18卷 1039-1042页

作者： Yushuang Liu, Dong Ren * college of life science, Capital normal University, 105 Xisanhuanbeilu, Haidian District, Beijing 100037, china college of life science Capital Normal University 105 Xisanhuanbeilu Haidian District Beijing 100037 China

Two new genera and two new species of family Taeniopterygidae, Mengitaenioptera multiramis gen. et sp. nov. and Noviramonemoura trinervis gen. et sp. nov. are described. These fossils were collected from Daohugou Village (the Middle Jurassic), Inner Mongolia, china. Hitherto, these fossil species from Daohugou are the oldest taeniopterygids. Both simple and complex venations simultaneously occurred in this group, which reveals that the early diversification of taeniopterids was well underway by the Middle Jurassic. Therefore, we prefer to adopt the Comstock’s opinion that the venation of taeniopterids was derived from the simple venation of the older group (such as Palaeonemouridae) at much ancient geological time ago. Some of the descendants carried this simple venation; others evolved into complex venation with many additional crossveins and branches.

关键词： Plecoptera Taeniopterygidae Daohugou Inner Mongolia Middle Jurassic

An octopamine-specific GRAB sensor reveals a monoamine relay circuitry that boosts aversive learning

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National science Review 2024年第5期11卷 186-201页

作者： Mingyue Lv Ruyi Cai Renzimo Zhang Xiju Xia xuelin Li Yipan Wang Huan Wang Jianzhi Zeng Yifei Xue Lanqun Mao Yulong Li State Key Laboratory of Membrane Biology School of Life SciencesPeking University State Key Laboratory of Brain and Cognitive science Institute of Biophysics Chinese Academy of Sciences PKU-IDG/Mc Govern Institute for Brain Research Yuanpei college Peking University Peking-Tsinghua Center for life sciences Academy for Advanced Interdisciplinary Studies Peking University Peking University–Tsinghua University–National Institute of Biological sciences Joint Graduate Program Academy for Advanced Interdisciplinary Studies Peking University Institute of Molecular Physiology Shenzhen Bay Laboratory college of Chemistry Beijing Normal University Chinese Institute for Brain Research

Octopamine（OA）,analogous to norepinephrine in vertebrates,is an essential monoamine neurotransmitter in invertebrates that plays a significant role in various biological functions,including olfactory associative ***,the spatial and temporal dynamics of OA in vivo remain poorly understood due to limitations associated with the currently available methods used to detect *** overcome these limitations,we developed a genetically encoded GPCR activation-based（GRAB） OA sensor called *** sensor is highly selective for OA and exhibits a robust and rapid increase in fluorescence in response to extracellular *** GRABOA1.0,we monitored OA release in the Drosophila mushroom body（MB）,the fly's learning center,and found that OA is released in response to both odor and shock stimuli in an aversive learning *** OA release requires acetylcholine（ACh） released from Kenyon cells,signaling via nicotinic ACh ***,we discovered that OA amplifies aversive learning behavior by augmenting dopamine-mediated punishment signals via Octβ1R in dopaminergic neurons,leading to alterations in synaptic plasticity within the ***,our new GRABOA1.0sensor can be used to monitor OA release in real time under physiological conditions,providing valuable insights into the cellular and circuit mechanisms that underlie OA signaling.

关键词： octopamine dopamine GRAB sensor learning and memory

Molecular structure and biological function of proliferating cell nuclear antigen

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Progress in Natural science:Materials International 2007年第10期17卷 1127-1135页

作者： Song Nanmeng1, Sang Jianli1 and Xu Heng2(1. Institute of Cell Biology, college of life science, Beijing normal University, Beijing 100875, china 2. Emory University school of Medicine, GA 30332, USA) Institute of Cell Biology College of Life Science Beijing Normal University Beijing 100875 China school of Medicine Emory University GA 30332 United States

Proliferating cell nuclear antigen (PCNA) is the core component of replication complex in eukaryote. As a processive factor of DNA polymerase delta, PCNA coordinates the replication process by interacting with various replication proteins. PCNA appears to play an essential role in many cell events, such as DNA damage repair, cell cycle regulation, and apoptosis, through the coordination or organization of different partners. PCNA is an essential factor in cell proliferation, and has clinical significance in tumor research. In this article we review the functional structure of PCNA, which acts as a function switch in different cell events.

关键词： PCNA Function Switch PCNA Binding Motif Cell Cycle DNA Replication DNA Repair.

Universal approximation of polygonal fuzzy neural networks in sense of K-integral norms

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science china(Information sciences) 2011年第11期54卷 2307-2323页

作者： WANG GuiJun 1 & LI XiaoPing 2 1 school of Mathematics science,Tianjin normal University,Tianjin 300387,china 2 school of Management,Tianjin normal University,Tianjin 300387,china school of Mathematics science Tianjin Normal University Tianjin China school of Management Tianjin Normal University Tianjin China

In this paper,we introduce polygonal fuzzy numbers to overcome the operational complexity of ordinary fuzzy numbers,and obtain two important inequalities by taking advantage of their fine *** presenting an actual example,we demonstrate that the approximation capability of polygonal fuzzy numbers is ***,the concepts of K-quasi-additive integrals and K-integral norms are *** the polygonal fuzzy numbers space satisfies separability,the density problems for several functions spaces can be studied,by means of fuzzy-valued simple functions and fuzzy-valued Bernstein *** establish that the class of the integrally-bounded fuzzy-valued functions spans a complete and separable metric space in the K-integral ***,in the sense of K-integral norms,the universal approximation of fourlayer regular polygonal fuzzy neural networks for fuzzy-valued simple functions is ***,we show that this type of networks also possesses universal approximation for the class of integrally-bounded fuzzyvalued *** result indicates that the approximation capability which regular polygonal fuzzy neural networks for continuous fuzzy systems can be extended as for general integrable systems.

关键词： polygonal fuzzy numbers K-quasi-additive integrals K-integral norms polygonal fuzzy neural networks universal approximations

Scenario simulation and forecast of land use/cover in northern china

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Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2,3 & HE ChunYang 3 1 college of Geographical science, Chongqing normal University, Chongqing 400047, china 2 college of Resources and Environmental science, Chongqing University, Chongqing 400044, china 3 college of Resources science & Technology, Beijing normal University, Beijing 100875, china college of Geographical science Chongqing Normal University Chongqing China college of Resources and Environmental science Chongqing University Chongqing China college of Resources science & Technology Beijing Normal University Beijing China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

Taxonomic circumscription of Sinojackia xylocarpa (Styracaceae)

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Journal of Systematics and Evolution 2011年第2期49卷 163-164页

作者： 1 Li-Qun LUO 2 Chi LUO 1 (Department of Chemistry and life science, Leshan normal University, Leshan 614004, china) 2 (Department of Mathematics, Leshan normal University, Leshan 614004, china) (Department of Chemistry and life science Leshan Normal University Leshan 614004 China) (Department of Mathematics Leshan Normal University Leshan 614004 China)

Sinojackia xylocarpa Hu in Journ. Arn. Arb. 9: 130. 1928. Type: china. Jiangsu: Nanjing, Y. L. Keng 1376 (PE!). Sinojackia rehderiana Hu in Journ. Arn. Arb. 11: 227. 1930, syn. nov. Type: china. Jiangxi: Nanchang, H. ... 详细信息

关键词： PE Styracaceae Taxonomic circumscription of Sinojackia xylocarpa

Nitrogen content features of several indigenous evergreen and decidous tree species in Chongqing region

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西南师范大学学报(自然科学版) 1999年第5期24卷 586-593页

作者： Zeng\ Bo school of life science,Southwest china normal University,Chongqing 400715 西南师范大学重庆

To aid to reveal the basic physiological differences existing between evergreen and deciduous plants, so as to facilitate our understanding of relationships between physiological features of evergreen & deciduous plants and their corresponding growth and biomass production, nitrogen content patterns of four indigenous tree species in Chongqing region including evergreen and deciduous plants growing in optimal conditions were analyzed. It is shown that leaf nitrogen content of deciduous tree species was significantly higher than that of evergreen tree species. Based on this result, it can be inferred that researched evergreen and deciduous tree species had basic differences in their leaf nitrogen content. There were no significant differences appeared between studied evergreen and deciduous tree species on nitrogen content of branches and stems. Compared with branch and stem, leaves had highest nitrogen content unexceptionally for all researched plants regardless of species. Nitrogen content of stems decreased with the age of stem for all investigated evergreen and deciduous species.

关键词： evergreen deciduous tree species nitrogen content Chongqing

Analysis and Key Parameter Optimization Design of Leningrader Seal Performance

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Wuhan University Journal of Natural sciences 2024年第2期29卷 177-192页

作者： YANG Dongya WANG xuelin WANG Feng ZHANG Hailong GAO Gui college of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730050Gansu China Wenzhou Pump and Valve Engineering Research Institute Lanzhou University of TechnologyWenzhou 325000ZhejiangChina State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000GansuChina

In order to improve the performance and service life of the Leningrader seal of the Stirling engine piston rod,interference,pre-load and friction coefficient were taken as influencing factors,and the curved surface response method was adopted to reduce the contact stress of sealing surface and von Mises stress of the sealing sleeve as the response index,with the optimization goal of reducing wear and extending *** above three key parameters are analyzed and optimized,the influence of each parameter on the sealing performance and service life is obtained,and the best combination scheme of the three is *** results show that the interaction between pre-tightening force and interference fit has the greatest impact on contact *** interaction between interference fit and friction coeffi-cient has the most significant effect on von Mises *** optimized parameters can reduce the maximum contact stress and maximum von Mises stress of the sealing sleeve by 26.3%and 20.6%,respectively,under a media pressure of 5-9 *** bench verification shows that the leakage of the optimized sealing device in 12 h is reduced by 0.44 cc·min^(-1)(1 cc=1 cm^(3)).The wear rate of the sealing sleeve is 1.08%before optimization and 0.45%after optimization,indicating that the optimized parameters in this paper are effective.

关键词： Leningrader seal Stirling engine performance analysis optimized design parameter configuration

Microstructure and Element Composition of Shell Plates of Liolophura japonica

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Wuhan University Journal of Natural sciences 2010年第2期15卷 176-184页

作者： CHEN Daohai1,2 1. college of Fisheries, Ocean University of china, Qingdao 266003, Shangdong, china 2. life science and Technology school, Zhanjiang normal University, Zhanjiang 524048, Guangdong, china college of Fisheries Ocean University of China Qingdao China life science and Technology school Zhanjiang Normal University Zhanjiang China

The microstructure characteristics of shell plates of chiton Liolophura japonica Lischke were analyzed using environmental scanning electron microscopy （ESEM）. The results show that the internal structure of the shell plate of chiton Liolophurajaponica is composed of seven calcium layers which were crossed lamellar crystallites, homoge- neous structure, granular crystallites, and trabecular type crystallites. The element compositions of shell plates were analyzed using X-ray photoelectron spectroscopy （XPS）. The results determined by XPS show that the surface chemical states of various layers are different. There are 13 elements （Na, O, N, C, S, P, Ca, C1, Si, A1, K, Fe, Mg） on the shell plate of chiton L. japonica. Among the 13 elements, 11 are on the outside pigment layer except K and S. Among seven layers of shell plate, there is the largest quantity of elements on the outside pigment layer, and the least quantity of elements is on layer C （Articulamentum auctorum）. There are 7 elements on the layer C （Articulamentum auctorum）. Be- sides calcium carbonate, there are some inorganic compounds on the shell plate, such as NaC1, MgO, A1203, silicate, sulfate and phosphate. There are some organic chemical components, such as carbohydrate, organic sulfide, and organic nitride on the shell plates.

关键词： Liolophura japonica environmental scanning electron microscope X-ray photoelectron spectroscopy (XPS) microstructure of shell plate