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K^+channels inhibited by hydrogen peroxide mediate abscisic acid signaling in Vicia guard cells 被引量:26
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作者 ZhanX MiaoYC 《Cell Research》 SCIE CAS CSCD 2001年第3期195-202,共8页
A number of studies show that environmental stress conditions increase abscisic acid (ABA) and hydrogen peroxide (H2O2) levels in plant cells. Despite this central role of ABA in altering stomatal aperture by regulati... A number of studies show that environmental stress conditions increase abscisic acid (ABA) and hydrogen peroxide (H2O2) levels in plant cells. Despite this central role of ABA in altering stomatal aperture by regulating guard cell ion transport, little is known concerning the relationship between ABA and H2O2 in signal transduction leading to stomatal movement. Epidermal strip bioassay illustrated that ABA- inhibited stomatal opening and ABA-induced stomatal closure were abolished partly by externally added catalase (CAT) or diphenylene iodonium (DPl), which are a H2O2 scavenger and a NADPH oxidase inhibitor respectively. In contrast, internally added CAT or DPI nearly completely or partly reversed ABA-induced closure in half-stoma. Consistent with these results, whole-cell patch-clamp analysis showed that intracellular application of CAT or DPI partly abolished ABA-inhibited inward K+ current across the plasma membrane of guard cells. H2O2 mimicked ABA to inhibit inward K+ current, an effect which was reversed by the addition of ascorbic acid (Vc) in patch clamping micropipettes. These results suggested that H2O2 mediated ABA-induced stomatal movement by targeting inward K+ channels at plasma membrane. 展开更多
关键词 Hydrogen peroxide abscisic acid K+ channels patch clamp vicia guard cell.
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Forest landscape patterns dynamics of Yihe-Luohe river basin 被引量:4
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作者 DINGShengyan SHANGFude +2 位作者 QIANLexiang CAOXinxiang LIShuang 《Journal of Geographical Sciences》 SCIE CSCD 2003年第2期153-162,共10页
Based on the information from forest resources distribution maps of Luoning County of 1983 and 1999, six indices were used to analyze spatial patterns and dynamics of forest landscapes of t... Based on the information from forest resources distribution maps of Luoning County of 1983 and 1999, six indices were used to analyze spatial patterns and dynamics of forest landscapes of the typical region in the middle of the Yihe-Luohe river basin. These indices include patch number, mean patch area, fragment index, patch extension index, etc. The results showed that: (1) There was a rapid increase in the number of patch and total area from 1983 to 1999 in the study area. The fragment degree became very high. (2) The area of all the forest patch types had witnessed great changes. The fractal degree of each forest patch type became big from 1983 to 1999. The mean extension index of Robinia pseudoacacia forest, non-forest, shrub forest, sparse forest, and Quercus species forest increased rapidly, but that of economic forest became zero. The fractal dimension each showed that forest coverage has been promoted. (3) The changes of landscape patterns were different in different geomorphic regions. From 1983 to 1999 the vegetation cover area, the gross number and the density of patch, diversity and evenness of landscape were all reduced greatly in gullies and ravines, but the maximum area and the mean area of patch types were increased. In hilly region, both the forest cover area and the number of patch increased from 1983 to 1999, but the mean area of patch was reduced greatly. In mountain region, even though the area under forest canopy reduced from 1983 to 1999, the patch number was increased greatly, the mean area of all patch types was reduced, the extension index, diversity index and evenness index of landscape were all increased. Furthermore, because of different types of land use, human activity and terrain, the vegetation changes on northern and southern mountain slopes were different. According to these analyses, the main driving forces, such as the policies of management, market economy, influence of human activities etc. are brought out. 展开更多
关键词 FOREST landscape pattern DYNAMICS geomorphic zone Yihe-Luohe river basin Luoning County CLC number:S718.5 Q948.2 P901
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Landscape pattern dynamics of water body in Kaifeng city in the 20th century 被引量:5
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作者 CAOXinxiang DINGShengyan 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期106-114,共9页
Landscape spatial pattern mainly refers to the distribution of patches, which are different in size and shape in space owing to the interaction of various ecological activities. In landscape ecology study, landscape p... Landscape spatial pattern mainly refers to the distribution of patches, which are different in size and shape in space owing to the interaction of various ecological activities. In landscape ecology study, landscape pattern has been one of the key study areas. Water body landscape plays an important role in the development history of a city, but at present city water body landscape in many cities has been destroyed, hence protecting water body in the city is becoming more and more important. In order to protect city water body landscape reasonably, the precondition is to probe the dynamics of water body landscape. Based on historical data and remote sensing data, six indexes including patch number, patch area, landscape dominance index, fractal dimension, patch density and connectivity index etc. were used to analyze landscape pattern dynamics of water body in Kaifeng city since the end of the Qing Dynasty (in the 20th century). The results showed: (1) Since the end of the Qing Dynasty, landscape area of water body in Kaifeng city increased first and then decreased from 1898 to 2002AD; the landscape dominant degree had the same changing tendency with the area. (2) Patch number of water body landscape in Kaifeng city had an increase from 1898 to 2002, but maximum area of patch, minimum area of patch and average area of patch decreased, which resulted in an increase in landscape fragment degree. (3) Connectivity index decreased and fractal dimension increased from 1898 to 2002. The reasons for these changes were the repeated overflows and flooding of the Yellow River and the influence of human activities. 展开更多
关键词 landscape pattern water body DYNAMICS Kaifeng city the early 20th century
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Rice bicoid-related cDNA sequence and its expression during early embryogenesis 被引量:3
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作者 YangZX AnGY 《Cell Research》 SCIE CAS CSCD 2001年第1期74-80,共7页
Bicoid is one of the important Drosophila maternal genes involved in the control of embryo polarity and larvae segmentation. To clone and characterize the rice bicoid-related genes, one cDNA clone, Rb24 (EMBL accessio... Bicoid is one of the important Drosophila maternal genes involved in the control of embryo polarity and larvae segmentation. To clone and characterize the rice bicoid-related genes, one cDNA clone, Rb24 (EMBL accession number: AJ2771380), was isolated by screening of rice unmature seed cDNA library. Sequence analysis indicates that Rb24 contains a putative amino acid sequence, which is homologous to unique 8 amino acids sequence within Drosophila bicoid homeodomain (50% identity, 75% similarity) and involves a lys-9 in putative helix 3. Northern blot analysis of rice RNA has shown that this sequence is expressed in a tissue-specific manner. The transcript was detected strongly in young panicles, but less in young leaves and roots. This results are further confirmed with paraffin section in situ hybridization. The signal is intensive in rice globular embryo and located at the apical tip of the embryo, then, along with the development of embryo, the signal is getting reduced and transfers into both sides of embryo. The existence of bicoid-related sequence in rice embryo and the similarity of polar distribution of bicoid and Rb24 mRNA in early embryo development may implicates a conserved maternal regulation mechanism of body axis presents in Drosophila and in rice. 展开更多
关键词 Base Sequence Body Patterning Cloning Molecular DNA Complementary Gene Expression Regulation Plant Genes Plant Homeodomain Proteins Molecular Sequence Data Oryza sativa Protein Structure Tertiary Research Support Non-U.S. Gov't Seeds Sequence Homology Nucleic Acid TRANS-ACTIVATORS
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Some Identities Involving Square of Fibonacci Numbers and Lucas Numbers 被引量:11
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作者 LIUDuan-sen LIChao YANGCun-dian 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第1期67-68,共2页
By studying the properties of Chebyshev polynomials, some specific and mean-ingful identities for the calculation of square of Chebyshev polynomials, Fibonacci numbersand Lucas numbers are obtained.
关键词 Chebyshev polynomials Fibonacci numbers Lucas numbers IDENTITY
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Regional agricultural landscape pattern changes along the Yellow River in Henan Province from 1987 to 2002 被引量:5
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作者 LIANG Guofu DING Shengyan LI Zhiheng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第4期415-422,共8页
Agricultural landscape along the riparian zones is designated as important landscape components for partly controlling water quality, biodiversity, as well as for their aesthetic role in landscapes. Therefore, the cha... Agricultural landscape along the riparian zones is designated as important landscape components for partly controlling water quality, biodiversity, as well as for their aesthetic role in landscapes. Therefore, the change of agricultural landscape along the riparian zones is at the top of the agenda for many policy makers and landscape planners. As a basis for conservation management, sufficient information about landscape structure should be provided. In the present study, we reconstructed the former landscape structure and elucidated the changes in landscape patterns during a period of about 15 years. Two sets of maps were used: a landsat-5 TM image (1987) and landsat-7 ETM image (2002). The frequency index, landscape diversity index and landscape fragmentation index were calculated for analyses. The results showed that: (1) the areas of the irrigated land, river, forest and beach landscape classes presented a decreasing trend while the areas of landscape classes of pool, paddy fields, dry land and construction land increased. (2) Disturbed by human activity, landscape diversity index increased but landscape fragmentation index decreased. In short, Human activities have had important influences on agricultural landscape of the riparian zones along the Yellow River in Henan Province. 展开更多
关键词 agricultural landscape landscape pattern change the Yellow River Henan Province
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Isolation and Identification of Capillarin from Artemisia Ordosica Kraschen 被引量:6
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作者 ZHAODong-Bao JIANGYan-Feng +2 位作者 XIChan-Juan LIUXiu-Hua WANGHan-Qing 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第6期637-640,共4页
Capillarin was isolated from Artemisia Ordosica Kraschen and characterized by IR, 1H-NMR, 13C-NMR, 1H-1HCOSY, HMQC, HMBC and EIMS, and its crystal structure was determined by single-crystal X-ray diffraction analysis ... Capillarin was isolated from Artemisia Ordosica Kraschen and characterized by IR, 1H-NMR, 13C-NMR, 1H-1HCOSY, HMQC, HMBC and EIMS, and its crystal structure was determined by single-crystal X-ray diffraction analysis with the following data: triclinic, space group P1, Z = 2, a = 7.226(6), b = 7.297(6), c = 11.042(8) ?, α = 74.695(12), β = 78.479(12), γ = 62.063(10)°, V = 494.2(6) ?3, Mr = 198.21, Dc = 1.332 g/cm3, F(000) = 208, μ = 0.089 mm-1, S = 1.023, (?/σ)max = 0.000, the final R = 0.0408 and wR = 0.1110. The largest peak and deepest hole on the final difference Fourier map are 0.219 and –0.161 e/?3, respectively. The bond lengths and bond angles of the molecule are also given. 展开更多
关键词 capillarin Artemisia Ordosica Kraschen single-crystal X-ray diffraction crystal structure
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图式流形 被引量:10
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作者 刘亚星 李起升 《Chinese Quarterly Journal of Mathematics》 CSCD 1994年第4期46-51,共6页
The discovery of manifold is a major advance in modern mathematics.In 1974,J.W.Morgan and D.P.Sullivan Surggest the concept of a Z/n manifold.We think that,it is more useful to suggest the concept of a graphlike manif... The discovery of manifold is a major advance in modern mathematics.In 1974,J.W.Morgan and D.P.Sullivan Surggest the concept of a Z/n manifold.We think that,it is more useful to suggest the concept of a graphlike manifold and research related topics.And these works will be done in this paper. 展开更多
关键词 图式流形 不变式
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Electrochemical Synthesis of Polythiophene in an Ionic Liquid 被引量:4
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作者 JiaHuaSHI XunSUN 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第4期306-307,共2页
Polythiophene (PTh) was prepared by the direct electrochemical synthesis in an ionic liquid ([BMIM]PF6) containing 0.1 mol/L thiophene by cyclic voltammetry, constant potential and constant current techniques. It is ... Polythiophene (PTh) was prepared by the direct electrochemical synthesis in an ionic liquid ([BMIM]PF6) containing 0.1 mol/L thiophene by cyclic voltammetry, constant potential and constant current techniques. It is found that smooth and bluegreen PTh films can be obtained at a potential of ca. +1.75 V ( vs. Ag/AgCl ) or a current of ca. 1.5 mA cm-2 in the ionic liquid. 展开更多
关键词 POLYTHIOPHENE electrochemical synthesis ionic liquid.
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The Asymptotic Property of Generalized Taylor Remainder "Mean Value Point" 被引量:4
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作者 RENLi-shun ZHANGCai-yu 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第3期314-318,共5页
This paper discussed asymptotic property of Taylor remainder 'mean value point' in normed Linear space. The asymptotic progerty of 'mean value point' is solved when f(n+i)(x0)h(n+i) = 0(i = 1, 2,..., p... This paper discussed asymptotic property of Taylor remainder 'mean value point' in normed Linear space. The asymptotic progerty of 'mean value point' is solved when f(n+i)(x0)h(n+i) = 0(i = 1, 2,..., p - 1) and f(n+p)(x0)h(h+p) don't exist. Meanwhile, achieve more general asymptotic estimation formula. Make many former results are just because of special case of the pager. 展开更多
关键词 FUNCTIONAL F-derivative Gα-derivative mean value point assymptotic property
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Multisymplectic Structure-Preserving in Simple Finite Element Method in High Dimensional Case 被引量:2
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作者 BAIYong-Qiang LIUZhen +1 位作者 PEIMing ZHENGZhu-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第1X期1-8,共8页
In this paper, we study a finite element scheme of some semi-linear elliptic boundary value problems in high-dhnensjonal space. With uniform mesh, we find that, the numerical scheme derived from finite element method ... In this paper, we study a finite element scheme of some semi-linear elliptic boundary value problems in high-dhnensjonal space. With uniform mesh, we find that, the numerical scheme derived from finite element method can keep a preserved multisymplectic structure. 展开更多
关键词 有限元方法 半线性椭圆边界值问题 高维空间 数值分析 多偶对结构 微分方程
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Relationships between energy consumption and climate change in China 被引量:3
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作者 QIANHuaisui YUANShunquan +1 位作者 SUNJiulin LIZehui 《Journal of Geographical Sciences》 SCIE CSCD 2004年第1期87-93,共7页
Energy consumption has an inevitable connection with economic level and climate. Based on selected data covering annual total energy consumption and its composition and that of all kinds of energy i... Energy consumption has an inevitable connection with economic level and climate. Based on selected data covering annual total energy consumption and its composition and that of all kinds of energy in 1953-1999, the annual residential energy consumption and the coal and electricity consumption in 1980-1999 in China, the acreage of crops under cultivation suffered from drought and flood annually and gross domestic product (GDP) in 1953-1999 in the whole country, and mean daily temperature data from 29 provincial meteorological stations in the whole country from 1970 to 1999, this paper divides energy consumption into socio-economic energy consumption and climatic energy consumption in the way of multinomial. It also goes further into the relations and their changes between the climate energy consumption and climate factor and between the socio-economic energy consumption and the economic level in China with the method of statistical analysis. At present, there are obvious transitions in the changing relationships of the energy consumption to economy and climate, which comprises the transition of economic system from resource-intensive industry to technology-intensive industry and the transition of climatic driving factors of the energy consumption from driven by the disasters of drought and flood to driven by temperature. 展开更多
关键词 energy consumption ECONOMY CLIMATE China
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L—Fuzzy群(I) 被引量:3
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作者 姜保庆 孙荣光 《Chinese Quarterly Journal of Mathematics》 CSCD 1994年第1期14-22,共9页
In this paper,the L-fuzzy group theory in a general frame is established,which is a generalization of [1-4].
关键词 L-FUZZY群 WPO子群 LF子群
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L—fuzzy群(Ⅱ) 被引量:2
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作者 姜保庆 孙荣光 《Chinese Quarterly Journal of Mathematics》 CSCD 1994年第4期91-97,共7页
This paper is a continuation of [1].In paper[1],the concept of LF group was introduced.In this paper,the concept of OP homomorphism will be introduced and its properties will be discussed.
关键词 L-FUZZY群 模糊数学 保序同态
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Some Applications of E-wavelet Multipliers 被引量:2
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作者 LIDeng-feng CHENGJun-fang 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第3期292-299,共8页
Let E= .A measurable function v is called an E- waveletmultiplier if (vψ) is an E-wavelet whenever ψ is an E-wavelet. Some characterizations and applications of E-wavelet multiplier were considered in [1]. In this p... Let E= .A measurable function v is called an E- waveletmultiplier if (vψ) is an E-wavelet whenever ψ is an E-wavelet. Some characterizations and applications of E-wavelet multiplier were considered in [1]. In this paper, we give some other applications of E-wavelet multiplier, and prove that the set of all MRA E-wavelets is arcwise connected. 展开更多
关键词 WAVELET wavelet multiplier multiresolution analysis
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Multisensor Distributed Track Fusion AlgorithmBased on Strong Tracking Filter and Feedback Integration^1) 被引量:1
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作者 YANGGuo-Sheng WENCheng-Lin TANMin 《自动化学报》 EI CSCD 北大核心 2004年第2期244-250,共7页
A new multisensor distributed track fusion algorithm is put forward based on combiningthe feedback integration with the strong tracking Kalman filter. Firstly, an effective tracking gateis constructed by taking the in... A new multisensor distributed track fusion algorithm is put forward based on combiningthe feedback integration with the strong tracking Kalman filter. Firstly, an effective tracking gateis constructed by taking the intersection of the tracking gates formed before and after feedback.Secondly, on the basis of the constructed effective tracking gate, probabilistic data association andstrong tracking Kalman filter are combined to form the new multisensor distributed track fusionalgorithm. At last, simulation is performed on the original algorithm and the algorithm presented. 展开更多
关键词 数据融合 数据关联算法 数据处理 多传感器分布式航迹融合算法 仿真 状态估计
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The Two Patterns of High Exact Difference in Convection Equation 被引量:2
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作者 YANGHui PENGXing 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第3期328-330,共3页
This paper gives two patterns of high exact d ifference in solving convection equation. The error of cut section is to O(Δ t 2+Δx 4).
关键词 convection equation the pattern of difference the e rror of cut section
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关于弱合数的分布 被引量:1
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作者 王天泽 李国强 《Chinese Quarterly Journal of Mathematics》 CSCD 1994年第2期29-33,共5页
Some asymptotic formulas related to the weakly composite numbers are given in this paper.
关键词 弱合数 分布 渐近公式
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The Counting Problem of an Order N-group of Set 被引量:1
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作者 WANGJing-zhou ZHANGHai-mo 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第3期283-285,共3页
In this paper, we discuss the counting prob lem of an order n-group of set (A 1,A 2,…,A n) which satisfies ∪ni=1A i={a 1,a 2,…,a m} and one of the following: (1) ∩ni=1A i=Φ; (2) ∩ni=1A i={b 1,b 2,…,b k};(3)... In this paper, we discuss the counting prob lem of an order n-group of set (A 1,A 2,…,A n) which satisfies ∪ni=1A i={a 1,a 2,…,a m} and one of the following: (1) ∩ni=1A i=Φ; (2) ∩ni=1A i={b 1,b 2,…,b k};(3) ∩ni=1A 1{b 1,b 2,…,b k}; (4) A i≠Φ (i=1,2,…,k). We solve these problems by element analytical meth od. 展开更多
关键词 an order n-group of set element analytical meth od COUNTING
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A Method for Solving Exact Solution to Two-dimensional Korteweg-de Vires-Burgers Equation 被引量:1
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作者 姜伟林 张解放 《Chinese Quarterly Journal of Mathematics》 CSCD 1994年第3期102-103,共2页
The exact solition wave solution for the two-dimensional Korteweg-de Vires-Bursers equation is obtuind via introducing nonlinear transformations. This method f which is different from reference [1],here is very concis... The exact solition wave solution for the two-dimensional Korteweg-de Vires-Bursers equation is obtuind via introducing nonlinear transformations. This method f which is different from reference [1],here is very concise and primary. The method in this letter can be applied to other nonlinear equations. 展开更多
关键词 two-dinemsional Kortewegde Vries-Burgers
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