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Cloning of artemisinin biosynthetic cDNAs and novel ESTs and quantification of low temperature-induced gene overexpression

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Science china(Life Sciences) 2008年第3期51卷 232-244页

作者： ZENG QingPing1, ZHAO Chang1, YIN LuLu1, YANG RuiYi1, ZENG XiaoMei1, HUANG Ying2, FENG LiLing3 & YANG XueQin3 1 Laboratory of Biotechnology, Tropical Medicine Institute, guangzhou University of Chinese Medicine, guangzhou 5.04.5. {4. 2 guangzhou General Hospital, guangzhou Military Area Command of Chinese PLA, guangzhou 5.0010, {4. 3 Center of Artemisinin Research, guangzhou University of Chinese Medicine, guangzhou 5.04.5. {4. 1. Laboratory of Biotechnology Tropical Medicine Institute Guangzhou University of Chinese Medicine Guangzhou 510405 China 2. guangzhou General Hospital Guangzhou Military Area Command of Chinese PLA Guangzhou 510010 China 3. Center of Artemisinin Research Guangzhou University of Chinese Medicine Guangzhou 510405 China

To isolate and verify novel genes from qinghao (Artemisia annua) based on the development-specific and environment-induced transcriptomics, leaves have been harvested from the flowering A. annua plants and exposed to low temperature for isolation of total RNAs and cloning of full-length cDNAs and cDNA fragments, or expressed sequence tags (ESTs). After being sequenced and browsed for homol- ogy, these sequences have been submitted to GenBank. Among the accessed 75.sequences, 4.full-length cDNAs are highly homologous to the known A. annua genes, but 71 ESTs are absent in the sequence records of A. annua genes, in which 34.sequences are homologous to other plant genes, including 24.identified protein-coding sequences and 10 unidentified protein-coding sequences, while other 37 sequences are not present in the sequence records of any plant genes, representing the first cloned plant genes. In order to investigate the responsive patterns of A. annua genes to extreme envi- ronmental stresses, especially low temperature, the expression levels of 3 critical qinhaosu (artemisi- nin) biosynthetic genes, ADS, CYP71AV1 and CPR, have been measured in pre- and post-chilling A. annua seedlings cultured in vitro by semi-quantitative PCR (SQ-PCR). Consequently, ADS and CYP71AV1 genes are strongly induced by chilling, but CPR gene is not significantly affected by such treatment. Furthermore, induction of these genes by chilling can be potently suppressed by Ca2+ channel inhibitor LaCl3 or Ca2+ chelator EGTA, suggesting a putative involvement of Ca2+-CaM signal transduction pathway in chilling-induced overexpression of ADS and CYP71AV1 genes. The real-time fluorescent quantitative PCR (RFQ-PCR) assay of A. annua seedlings exposed to chilling has shown that the expression level of CaM gene is up-regulated for more than 2.5.folds, thereby confirming our above inference on the relevance of Ca2+-CaM-mediated signal transduction to chilling-induced gene overexpression. Finally, 7 newly iso

关键词： Artemisia annua expressed sequence tag (EST) abiotic stress signal transduction fluorescent quantification

PREPARATION AND PROPERTIES OF ETHYL-CYANOETHYL CELLULOSE/POLYACRYLIC ACID COMPOSITE FILMS WITH REFLECTION COLORS

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Chinese Journal of Polymer Science 2001年第3期19卷 277-282页

作者： Yong Huang Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 china Laboratory of Cellulose and Lignocellulosics Chemistry guangzhou Institute of Chemistry Chinese Academy of Sciences, guangzhou 5.065., china 中科院化学所北京

Ethyl-cyanoethyl cellulose [(E-CE)C]/acrylic acid (AA) becomes a cholesteric liquid crystalline solution withvivid colors when the (E-CE)C concentration is 4. wt%～5. wt%. (E-CE)C/polyacrylic acid (PAA) composites withcholesteric structure were prepared by polymerzing AA in (E-CE)C/AA liquid crystalline solutions. The layers of orderedpolymer chains in the cholesteric phase were inclined during polymerization and the degree of the inclination depended onthe polymerization temperature and the concentration of the solution before polymerization. The cholesteric structure in thecomposites could not be changed when temperature was lower than 100℃. Cross-linking of the PAA in compositesimproved their water-resistance. The cholesteric order of the composites without cross-linking was destroyed when theywhere immersed in water. The color derived from the selective reflection of the cholesteric phase of the cross-linkedcomposites turned from blue to red after the composites absorbed water. The color of the composites could be returned to theoriginal one when the absorbed water was removed from the swollen composites.

关键词： Cholesteric structure Composites Selective reflection Liquid crystalline solutions

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浅谈鹅毛绒含量的测试及影响因素

中国纤检 2024年第9期 48-51页

作者：梁长娣广州检验检测认证集团有限公司广东广州510000

本文介绍了GB/T 10288-2016《羽绒羽毛检验方法》标准中鹅毛绒含量的检测原理及计算,并对可能造成结果差异的各个影响因素进行梳理和分析,旨在为检测机构间操作手法和目光鉴别的统一提供参考,同时为企业的生产提供科学指引,以降低生产... 详细信息

本文介绍了GB/T 10288-2016《羽绒羽毛检验方法》标准中鹅毛绒含量的检测原理及计算,并对可能造成结果差异的各个影响因素进行梳理和分析,旨在为检测机构间操作手法和目光鉴别的统一提供参考,同时为企业的生产提供科学指引,以降低生产和贸易中的风险。

关键词：羽绒种类鹅毛绒含量影响因素

维普期刊数据库博看期刊

基于A-ECMS的增程式电动汽车能量管理策略设计及应用

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安庆师范大学学报（自然科学版） 2024年第2期30卷 47-51页

作者：张光洲梅琳合肥学院先进制造工程学院安徽合肥230601

增程式电动汽车因其电驱效率高、无里程焦虑等优点,在新能源汽车市场备受青睐。为了进一步提升其综合性能,本研究在MATLAB/Simulink环境下构建了增程式电动汽车仿真模型,并利用等效自适应因子以改进燃油消耗最小化算法,形成了基于A-ECM... 详细信息

增程式电动汽车因其电驱效率高、无里程焦虑等优点,在新能源汽车市场备受青睐。为了进一步提升其综合性能,本研究在MATLAB/Simulink环境下构建了增程式电动汽车仿真模型,并利用等效自适应因子以改进燃油消耗最小化算法,形成了基于A-ECMS的能量管理策略。结果表明,在WLTC循环工况测试中,A-ECMS能量管理策略的百公里综合油耗为6.4. L,综合燃油消耗量为0.71 L,均低于其他方法。最终的电池充电状态(SOC)为31.1%,与目标SOC的偏差仅为1.1%。该策略显著提升了燃油经济性和电池使用寿命,为增程式电动汽车性能优化提供了新的参考方法。

关键词：增程式电动汽车能量管理策略设计 ECMS

ID-WAVELETS METHOD FOR HAMMERSTEIN INTEGRAL EQUATIONS

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Journal of Computational Mathematics 1998年第6期16卷 499-508页

作者： Xian-biao Wang Wei Lin (Department of Mathematics, Zhongshan University, guangzhou 5.0275. china) Zhongshan Univ Dept Math Canton 510275 Peoples R China

The numerical solutions to the nonlinear integral equations of Hammerstein-type y(t) = f(t) + integral(0)(1)k(t, s)g(s, y(s))ds, t is an element of [0,1] are investigated. A degenerate kernel scheme basing on ID-wavelets combined with a new collocation-type method is presented. The Daubechies interval wavelets and their main properties are briefly mentioned. The rate of approximation solution converging to the exact solution is given. Finally we also give two numerical examples.

关键词： nonlinear integral equation interval wavelets degenerate kernel

Representation of Congruences on Regular Semigroups with Inverse Transversals

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Acta Mathematica Sinica,English Series 1999年第3期15卷 347-352页

作者： Limin Wang Xilin Tang Department of Mathematics, South china Normal University, guangzhou 5.0631, P. R. china Department of Mathematics, guangzhou Teacher’s College, guangzhou 5.04.0, P. R. china Department of Mathematics South China Normal University Guangzhou P. R. China Department of Mathematics Guangzhou Teacher’s College Guangzhou P.R. China

For a regular semigroup with an inverse transversal, we have Saito’s structure W(I, S°, Λ, *, α,β). We represent congruences on this kind of semigroups by the so-called congruence assemblage which consist of congruences on the structure component parts I, S° and Λ. The structure of images of this type of semigroups is also presented.

关键词： Inverse transversal Congruence Congruence assemblage

Identification and construction of Boolean functions with maximum algebraic immunity

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Science china(Information Sciences) 2010年第7期53卷 1379-1396页

作者： LIU MeiCheng, PEI DingYi & DU YuSong College of Mathematics and Information Sciences, guangzhou University, guangzhou 5.0006, china 1. College of Mathematics and Information Sciences Guangzhou University Guangzhou 510006 China

Boolean functions with maximum algebraic immunity have been considered as one class of cryptographically significant functions. It is known that Boolean functions on odd variables have maximum algebraic immunity if and only if a correlative matrix has column full rank, and Boolean functions on even variables have maximum algebraic immunity if and only if two correlative matrices have column full rank. Recently, a smaller matrix was used in the odd case. We find that one or two smaller matrices can be used in the even case and consequently present several sufficient and necessary conditions for Boolean functions with maximum algebraic immunity. This result advances the ability to identify whether Boolean functions on even variables achieve maximum algebraic immunity. We also present a construction algorithm for n-variable Boolean functions with maximum algebraic immunity, specially with the Hamming weights of ∑2 n i=0 -1 . It is easily realized for not too large n and helps construct balanced Boolean functions with maximum algebraic immunity on even variables. Furthermore, we present a sufficient and necessary condition for balanced Boolean functions to achieve maximum algebraic immunity and optimum algebraic degree, and modify the construction algorithm to con- struct Boolean functions on odd variables with maximum algebraic immunity, optimum algebraic degree and high nonlinearity.

关键词： Boolean functions MAI functions algebraic attacks algebraic immunity algebraic degree non-linearity

DIMPLE FORMATION ON FRACTURE SURFACE OF STEEL 5.SiMnMo

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Acta Metallurgica Sinica(English Letters) 1993年第2期6卷 140-143页

作者： LIANG Sizu LIANG Yaoneng LIU Zhengyi South china University of Technology,guangzhou,china Lecturer,Department of Mechanical Engineering No.2,South china University of Technology,guangzhou 5.064.,china South china Univ of Technology Guangzhou China

The fracture surface of the normalized steel 5.SiMnMo was observed,under tensile device at- tached on the SEM,to be of ductile dimple feature on the bainite which is composed of lath ferrite and austenite *** dimple is essentially nucleated in the *** the austenitic plastic deformation is remarkable during fracturing,the tear ridge of dimple is very sharp.

关键词： dimple plastic deformation ductile fracture steel 5.SiMnMo

Sand-dust Storm, Population and Environment in Northwest china

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Chinese Journal of Population,Resources and Environment 2004年第4期2卷 17-24页

作者： Liu Shao guangzhou Research Institute of Environmental Protection, guangzhou 5.0620, china guangzhou Research Institute of Environmental Protection Guangzhou 510620 China

Sand-dust storms are the result of the integrated influences of climate, geography, society and human factors. A theoretical framework is built to explain the coherence of population growth, agriculture change and environmental degradation. On the basis of the analysis of the causes of the sand-dust storm in terms of human factors, a discussion will be given to show that these factors are internally consistent with the theoretical framework. After that, it will look at china's Agenda 21 and try to find relevant measures to reduce such large sand-dust storms happening in Northwest china and eventually make this area develop sustainably.

关键词： Sand-dust storm population environment china’s Agenda 21 sustainability