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Characteristics of regional climate change and pattern analysis on Ordos Plateau

Journal of Environmental Sciences 2002年第4期14卷 568-576页

作者： li guo qing ZHENG Yuan run Laboratory of Quantitative Vegetation Ecology Institute of BotanyChinese Academy of SciencesBeijing 100093China.

The characteristics of precipitation, temperature and their combination determine the special ecological environment pattern of Ordos Plateau. Analyzing its evolutionary trend attributes to understanding the succession process of the ecological environment of Ordos Plateau and has crucial instructional significance on the ecological restoration research being conducted in this region. Four time scales, arranging from ten days, one month, one season(growing season contrasting to non growing season)to one year were adopted to analyze the climate data which included nearly 30 years and were collected by eight weather stations on Ordos Plateau. The results indicated that the mean annual temperature and the mean monthly temperature of February, September and December, had increased significantly during the late 30 years. The annual precipitation did not show significant changes but its distribution pattern had changed obviously. The ratio of precipitation of major growing season (May October)to annual precipitation had increased distinctively,and five counties' precipitation reached statistically significant level. And the ratio of precipitation of latter growing season (September)to one year decreased significantly while the ratio of non growing season(November next April)to one year changed insignificantly. The results showed that maybe the interaction of increased mean temperature and insignificant change of precipitation in non growing season was one of the reasons why the desertification of the region was deteriorating in recent years. Using some factors closely relating to vegetation succession such as mean annual temperature, mean annual precipitation, distributive pattern of precipitation, mean temperature of the coldest month, mean temperature of the warmest month, precipitation of the warmest month, mean temperature of growing season, precipitation of growing season, potential evapotranspiration(PET)and radiative dryness index(RDI), to synthetically anal

关键词： climate change climatic synthetical regionalization restoration ecology Ordos Plateau

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Synthesis and Crystal Structure of a New Lanthanum(III) 4-Cyanobenzoate Complex

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Chinese Journal of Structural Chemistry 2007年第5期26卷 575-579页

作者： li guo-qing li Yanb ZOU Wen-Qiang CHEN Qi-Yong ZHENG Fa-Kun guo guo-Cong Chemistry and life Science School Quanzhou Normal University Quanzhou Fujian 362000 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on theStructure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

A new dinuclear La（Ⅲ） complex [La2（4-cba）4[H（4-cba）2]2（phen）2（H2O）4] （4-Hcba = 4-cyanobenzoic acid and phen = 1,10-phenanthroline） 1 has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100 ℃ and structurally characterized by singlecrystal X-ray diffraction. Crystallographic data： C88H58La2N12O20, Mr = 1881.28, triclinic P1, a = 7.518（3）, b = 17.033（6）, c = 17.551（6）A, α = 115.333（4）, β = 92.9910（10）, γ = 99.366（5）°, V = 1985.3（12）A^3, Z = 1, Dc = 1.574 g/cm^3, F（000） = 944 μ = 1.145 mm^–1, the final R = 0.0281 and wR = 0.0686 for 6708 reflections with Ⅰ 〉 2σ（I）. In 1, two nine-coordinated La（Ⅲ） ions are connected by two 4-cba ligands in a syn-syn bidentate coordination mode, and the other six 4-cba ligands terminate the La（Ⅲ） ions, resulting in an isolated dinuclear structure. Two different types of intramolecular hydrogen bonds, asymmetrical O-H…O and symmetrical O…H…O, exist in the crystal. The title complex molecules are connected through hydrogen bonds and weak π-π stacking interactions to generate a 2-D layered network. The thermogravimetric analysis of 1 has also been discussed.

关键词： lanthanum(Ⅲ) complex 4-cyanobenzoic acid crystal structure hydrogen bonds

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RNA interference-mediated silencing of a Halloween gene spookier affects nymph performance in the small brown planthopper Laodelphax striatellus

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Insect Science 2015年第2期22卷 191-202页

作者： Shuang Jia Pin-Jun Wan li-Tao Zhou li-li Mu guo-qing li Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests College of Plant Protection Nanjing AgriculturalUniversity Nanjing China

Post-embryonic development of insects is highly dependent on ecdysteroid hormone 20-hydroxyecdysone. Halloween gene spookier （spok, cyp307a2） has been documented to be involved in ecdysteroidogenesis in Drosophila melanogaster and Bombyx mori. We describe here the cloning and characterization of Halloween gene spookier （Lsspok, Lscyp307a2） in the small brown planthopper Laodelphax striatellus, a hemipteran insect species. LsSPOK has three insect-conserved P450 motifs, that is, Helix-K, PERF motif and heme-binding domain. Temporal and spatial expression patterns of Lsspok were evaluated by quantitative polymerase chain reaction. Through the fouth- instar and the early fifth-instar stages, Lsspok showed two expression peaks in the second- and fifth-day fourth-instar nymphs, and two troughs in the first-day fourth and fifth in- stars. On day 5 of the fourth-instar nymphs, Lsspok clearly had a high transcript level in the thorax where prothoracic glands were located. Dietary introduction of double-stranded RNA of Lsspok in the nymph stage successfully knocked down the target gene, decreased expression level ofecdysone receptor （LsEcR） gene, caused nymphal lethality and delayed development. Ingestion of 20-hydroxyecdysone in Lsspok-dsRNA-exposed nymphs did not increase Lsspok expression level, but almost completely rescued the LsEcR mRNA level and relieved the negative effects on survival and development. Thus, our data suggest that the ecdysteroidogenic pathway is conserved in insects and LsSPOK is responsible for specific steps in ecdysteroidogenesis in L. striatellus.

关键词： development double-stranded RNA ecdysteroidogenesis Laodelphaxstriatellus lethality spookier

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Using Pre-Estimate with Feedback for Adaptation Web Server QoS Guarantee

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 256-262页

作者： WANG li SHEN qing-guo Institute of Communications Engineering PLA University of Science and Technology Nanjing 210007 Jiangsu China

The heterogeneity in the communicating terminals needs to he handled through software-supported adaptation, The real-time dynamical adaptation brings the system more time cost unavoidably. In this paper, we propose QoS pre-estimation for user admission control and system load control. Feedback acts as adjuster of the input parameters of the pre-estimate module. We present tests results to evaluate our approach, The test results show that our service quality control mechanism is effective.

关键词： pre-estimate feedback control QoS adaptation system

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Micro-porous TiO2 thin films grown on surface of Ti substrate

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中国有色金属学会会刊：英文版 2004年第z1期14卷 178-181页

作者： WU Xiao-hong QIN Wei JIANG Zhao-hua HU Xin-guo li qing-fen Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China School of Mechanics and Electronics Engineering Harbin Engineering University Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China School of Mechanics and Electronics EngineeringHarbin Engineering University Harbin 150001 China

Microporous titanium dioxide thin films have been grown on titanium plates by the micro-plasma oxidation method with different current densities (4, 6, 10 and 14 A/dm2). X-ray diffraction, scanning electronic microscopy and UV-Vis spectrophotometry were used to characterize the films. It is found that the films grown are microporous and consist of crystalline titanium dioxide. The micropore size and the content of anatase and rutile TiO2 phase increase with the applied voltage. The relatively higher degradation efficiency for rhodamine B is obtained in the film produced with a current density of 10 A/dm2.

关键词： micro-plasma oxidation TiO2 thin film photo-catalytic activity rhodamine B

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Validation of Reference Genes for Quantitative Real-Time PCR in Laodelphax striatellus

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Journal of Integrative Agriculture 2014年第4期13卷 811-818页

作者： HE Xiu-ting liU Cheng-cheng li Zhao-qun ZHANG Zan li guo-qing li Fei DONG Shuang-lin Key Laboratory of Integrated Management of Crop Diseases and Pests Ministry of Education/College of Plant ProtectionNanjing Agricultural University

The normalization of quantitative real-time PCR （qPCR） is important to obtain accurate gene expression data, and the most common method for qPCR normalization is to use reference genes. However, reference genes can be regulated under different conditions, qPCR has recently been used for gene expression study in Laodelphax striatellus, but there is no study on validation of the reference genes. In this study, five new housekeeping genes （LstrTUB1, LstrTUB2, LstrTUB3, LstrARF and LstrRPL9） in L. striatellus were cloned and deposited in the GenBank with accession numbers of JF728809, JF728810, JF728811, JF728807 and JF728806, respectively. Furthermore, mRNA expressions of the five genes and β-actin were measured by qPCR with insect samples of different instar at nymph stage, and the expression stabilities were determined by the software geNorm and NormFinder. As a result, ARF and RPL9 were consistently more stable than β-actin, while three TUB genes were less stable than β-actin. To determine the optimal number of reference genes used in qPCR, a pairwise variations analysis by geNorm indicated that two references ARF and RPL9 were required to obtain the accurate quantification. These results were fiarther confirmed by the validation qPCR experiment with chitinase gene as the target gene, in which the standard error of the mRNA quantification by using binary reference ARF-RPL9 was much lower than those by ARF, RPL9 or β-actin alone. Taken together, our study suggested that the combination of ARF-RPL9 could replace β-actin as the reference genes for qPCR in L. striatellus.

关键词： cDNA cloning housekeeping gene qPCR reference gene small brown planthopper

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Development of a PCR Diagnostic Kit for Cryptosporidium andersoni in Dairy Cow

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Agricultural Sciences in China 2007年第4期6卷 493-498页

作者： ZHOU Rong-qiong li guo-qing XIAO Shu-min li Wei-hua College of Veterinary Medicine South China Agricultural University Guangzhou 510642 P.R.China Department of Veterinary Medicine Rongchang Campus Southwest University Chongqing 402460 P.R.China

Cryptosporidiosis is an important zoonosis caused by the Cryptosporidium species. To develop a PCR diagnostic kit for molecular detection and differential diagnosis of Cryptosporidium spp., a portion of ITS-1 sequence of Cryptosporidium. andersoni was chosen as the target DNA for designing the species-specific primers （ZRQF/ZR）. The kit components were determined after the PCR amplification conditions were serially optimized. A series of tests were conducted in the specificity, sensitivity, stability, reproducibility, and stored period of the kit, respectively. The results showed that only C. andersoni were amplified specific band of about 500 bp, while Cryptosporidium. parvum, Cryptosporidium. baileyi, Eimeria sp of dairy cow, Toxoplasma gondii, Eimeria sp of pig, Ascaris suum, Cyclospora sp, and E. coli could not be amplified. 254 oocysts of C. andersoni was the lowest number that could be detected using the kit. The kit worked well after being stored at room temperature, 4 and -20℃ for nine months. Fecal specimens, which were collected from a total of 243 calves on four different dairy farms in Guangdong Province, China, and one dairy farm in Henan Province, China, were examined using the kit; the positive rate of the kit was 2-13% higher than that of the routine methods. The results indicated that the kit can detect fecal samples faster, more sensitively, and conveniently, and can provide a useful tool for the identification and differentiation of C. andersoni from the other Cryptosporidium species; it also has implications for further studies on molecular epidemiology and differential diagnostics of cryptosporidiosis in animals.

关键词： Cryptosporidium andersoni ITS-1 diagnostic kit detection dairy cow

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Ecological vulnerability analysis of Tibetan towns with tourism-based economy： a case study of the Bayi District

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Journal of Mountain Science 2018年第5期15卷 1101-1114页

作者： KAN Ai-ke li guo-qing YANG Xiao ZENG Ye-long TESREN Luobu HE Jie College of Geophysics Chengdu University of Technology Chengdu 610059 China State Key Laboratory of Resource and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China School of Resources and Environmental Engineering Ludong University Yantai 264025 China College of Forestry Guizhou University Guiyang 550025 China Institute of Science & Technology Information of Tibet Autonomous Region Lhasa 850000 China College of Tourism and Urban-RuraI Planning Chengdu University of Technology Chengclu 610059 China

This paper provides a generalizable mode for the ecological vulnerability evaluation for tourism planning and development in high mountain *** Bayi District located in southeastern Tibet is taken as a typical town to study the conflict between the protection of natural ecological environment and the exploitation of tourism resources. Based on the Sensitivity-Recovery-Pressure(SRP) framework, a set of vulnerability evaluation systems for plateau tourism regions were developed. The spatial principal component analysis(SPCA), remote sensing and GIS technologies were integrated to apply for spatial quantification of evaluation index system. The ecological vulnerability of the Bayi District was divided into five levels: potential, mild, moderate,severe, and extreme, and our results showed that significantly severe and extreme vulnerability areas were mainly distributed throughout the southwestern and central northern alpine pasture and glacial *** and mild vulnerability areas were mainly distributed in the vicinity of the Yarlung Zangbo River tributary basin. Then three tourism development and environmental protection zones were classified and appropriate measures for the protection were proposed. It also provides a reference for the spatial distribution of a range of areas that require different protection measures according to ecological vulnerability classification.

关键词： Ecological vulnerability Tourism area Tibet Spatial principal component analysis (SPCA) Moran's I model

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Development and Application of Nested PCR Assay for Detection of Dairy Cattle-Derived Cyclospora sp.

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Agricultural Sciences in China 2007年第12期6卷 1511-1516页

作者： XIAO Shu-min li guo-qing li Wei-hua ZHOU Rong-qiong YANG Jian-wei College of Veterinary Medicine South China Agricultural University Guangzhou 510642 P.R.China School of Safety Science and Engineering Henan Polytechnic University Jiaozuo 454000 P.R.China

To develop a nested PCR assay for the detection of cattle-derived Cyclospora sp., two pairs of primers were designed on the basis of the cattle-derived Cyclospora sp. sequences. These primers selectively amplified a 168-bp DNA fragment of the 18S rRNA gene of cattle-derived Cyclospora sp. With these primers, a nested PCR assay for the detection of cattlederived Cyclospora sp. was developed. The nested PCR assay was specific and there is no cross-reaction with other parasites, such as Eimeria spp., Cryptosporidium spp., Giardia sp., Toxoplasma sp., Trichuris sp. and cattle ciliate. The assay was able to detect as low as 2.85 × 10^-2 fg of the control positive DNA. The results of the detection of clinical samples indicated that the assay coincided with microscopic examination. The results show that the nested PCR assay will be an effective tool for the detection of Cyclospora sp. in cattle feces.

关键词： Cyclospora sp. dairy cattle nested PCR detection

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氧化物隔离对Si基片上生长L1_0相FePt薄膜磁性的影响

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物理学报 2018年第15期67卷 337-344页

作者：李丹李国庆西南大学物理科学与技术学院重庆400715

用MgO和SiO_2两种氧化物将FePt薄膜与Si(100)基片隔离,分析隔离层在FePt层发生A1→L1_0转变过程中的作用,寻找用Si母材涂敷L1_0-FePt磁性层来提高磁力显微镜针尖矫顽力的合理方案.采用磁控溅射法在400?C沉积Fe Pt薄膜,在不同温度进行2 ... 详细信息

用MgO和SiO_2两种氧化物将FePt薄膜与Si(100)基片隔离,分析隔离层在FePt层发生A1→L1_0转变过程中的作用,寻找用Si母材涂敷L1_0-FePt磁性层来提高磁力显微镜针尖矫顽力的合理方案.采用磁控溅射法在400?C沉积Fe Pt薄膜,在不同温度进行2 h的真空热处理,分析晶体结构和磁性的变化.结果表明:没有隔离层,Si基片表层容易发生扩散,50 nm厚FePt薄膜的矫顽力最大只有5kOe(1 Oe=10~3/(4π)A·m^(-1));而插入隔离层,矫顽力可以超过10 kOe;MgO在Si基片上容易碎裂,热处理温度不能高于600?C,用作隔离层,FePt的最大矫顽力为12.4 kOe;SiO_2与Si基片的晶格匹配更好,热膨胀系数差较小,能承受的最高热处理温度可以超过800?C,使得Fe Pt的矫顽力可以在5 kOe到15 kOe范围内调控,更适合用于制作矫顽力高并可控的磁力显微镜针尖.

关键词： FePt薄膜 Si基片氧化物隔离层热处理

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