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Oxidative stress related enzymes in response to chromium(VI) toxicity in Oxya chinensis (Orthoptera: Acridoidae)

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Journal of Environmental Sciences 2005年第5期17卷 823-826页

作者： LI Li-jun ZHANG Feng liu xue-mei GUO Ya-ping MA En-bo College of Life Science and Technology Shanxi University Taiyuan 030006 China Institution of Soil Science and Fertilizer Shanxi Academy of Agriculture Science Taiyuan 030031 China

The toxic effects of Cr（Vl） on antioxidant enzymes of Oxya chinensis（Orthoptera： Acridoidae） were determined. Changes in the activities of the antioxidant enzymes superoxide dismutase（SOD）, catalase（CAT）, and guaiacol peroxidase（GPx） were measured in O. chinensis insects injected with Cr（VI）. Fifth-nymphs of O. chinensis insects were injected with Cr（VI） with different concentrations （0, 75, 150, 225, 300, 375, 450 mg/kg of body weight）. The results showed that Cr（VI） led to the change of SOD, CAT, and GPx activities at different concentrations, which revealed that：（1） The oxidative stress of SOD increased with the increase of Cr （VI） concentration. （2） With the increase of Cr （VI） concentrations, CAT activities for females increased at lower concentrations, but decreased at higher concentration range, which indicated that antioxidant system of O. chinensis was not influenced by the presence of Cr （VI）. A very similar response to Cr（VI） effect for males indicated that Cr（VI） concentrations were not high enough to damage O. chinensis in terms of CAT. （3） The GPx activity for females increased in all treatments, which revealed that the damage power of Cr（VI） was increased with the increase of Cr（Vi） concentrations in terms of GPx, but the effect was not so remarkable. There was not a consistent trend of GPx activities for males in all treatments of Cr（VI）. Cr（VI）-induced changes in antioxidant enzymes were different for SOD, CAT and GPx, of which the tendency was that activities generally changed with increase of concentrations of Cr（VI） suggesting SOD, CAT, and GPx could serve as indices of oxidative stress to some extent.

关键词： Cr( VI ) Oxya chinensis oxidative stress superoxide dismutase(SOD) catalase (CAT) guaiacol peroxidase(GPx)

Noise-Induced Transition in a Voltage-Controlled Oscillator Neuron Model

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Communications in Theoretical Physics 2008年第7期50卷 257-260页

作者： XIE Hui-Zhang liu xue-mei AI Bao-Quan liu Liang-Gang LI Zhi-Bing Department of Physics Sun Yat-Sen University Guangzhou 510275 China School of Physics South China University of Technology Guangzhou 510640 China School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510631 China Faculty of Information Technology Macao University of Science and Technology Macao China

In the presence of Gaussian white noise,we study the properties of voltage-controlled oscillator neuronmodel and discuss the effects of the additive and multiplicative *** is found that the additive noise can accelerate andcounterwork the firing of neuron,which depends on the value of central frequency of neuron itself,while multiplicativenoise can induce the continuous change or mutation of membrane potential.

关键词： Gaussian white noise transition voltage-controlled oscillator neuron model

Syntheses, Crystal Structures and Hydrogen-bonding Motif of Two Glycoluril Derivatives

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Chinese Journal of Structural Chemistry 2019年第5期38卷 754-760,669页

作者： liu xue-mei WANG Dong-Hua SONG Xin-Jian WANG Jun-Gang Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province Hubei University for Nationalities Enshi 445000 China School of Chemical Engineering Guizhou Minzu University Guiyang 550025 China

The synthesis and aggregation behavior of two glycoluril derivatives were *** crystal of compound 1 belongs to the triclinic system,space group ■,with a=8.946（1）,b=13.445（2）,c=20.361（3）?,α=89.517（3）,β=84.405（3）,γ=86.325（3）°,Z=2,V=2432.1（6）?3,Dc=1.293 g·cm-3,C48H34N6O6·2DMSO,Mr=947.07,F（000）=992,μ=0.170 mm-1,the final R=0.1606 and wR=0.2410 for 4382 observed reflections（Ⅰ>2σ（Ⅰ））.The crystal of compound 2belongs to the monoclinic system,space group P21/c,with a=9.500（3）,b=24.522（8）,c=17.997（6）?,Z=2,V=4054（2）?3,Dc=1.296 g·cm-3,C48H34N6O6,Mr=790.81,F（000）=1648,μ=0.087mm-1,the final R=0.2146 and wR=0.2535 for 2878 observed reflections（Ⅰ>2σ（Ⅰ））.Unlike the highly conserved R22（8）hydrogen-bonding amide···amide homosynthon,the structural analysis indicated that compound 1 selected the C（20）hydrogen-bonding motif and 2 selected the R22（34）hydrogen-bonding motif,which revealed the competition from remote solvent molecule and the interference of the molecular hydrocarbon core in crystal *** supramolecular structure revealed molecule 1 is further linked into a one-dimensional chain and 2 into a two-dimensional interwoven plane by N–H···N hydrogen bonds.

关键词： hydrogen bond glycoluril supramolecuclar synthons crystal engineering

An Effective Reading Process： The Application of Annotation to English as a Foreign Language Reading

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Sino-US English Teaching 2015年第5期12卷 321-326页

作者： liu xue-mei Binzhou University Binzhou China

In this study, the author investigated insights of 15 college students majored in English as they explored their own use of annotation strategy and how they applied this strategy in effective reading process. As an action research, the report is an attempt to explore the role played by annotation in reading comprehension in English as a Foreign Language （EFL） classrooms. By means of learner diaries, the researcher found that annotation, as an efficient writing-to-learn strategy, is able to help EFL learners to research a deeper level of engagement and to encourage active reading. The findings also suggest that reading strategy training can be integrated with reading tasks in the EFL classrooms.

关键词： annotation interactive reading model learner diaries

Accumulation of cadmium and copper by female Oxya chinensis (Orthopera: Acridoidea) in soil-plant-insect system

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Journal of Environmental Sciences 2006年第2期18卷 341-346页

作者： LI Li-jun liu xue-mei DUAN Yi-hao GUO Ya-ping CHENG Bin GUO Jun XI Yu-ying MA En-bo Institution of Soil Science and Fertilizer Shanxi Academy of Agriculture Sciences Taiyuan 030031 China College of Life Science and Technology Shanxi University Taiyuan 030006 China School of Environmental Science and Resources Taiyuan 030006 China

One purpose of this research is to present accumulation of cadmium （Cd） and copper （Cu） by female Oxya chinensis （Orthopera： Acridoidea） in a simulated soil-plant-insect ecosystem treated with Cd. Fourth-instar nymphs of O. chinensis had been fed on wheat （Triticurn aestivum） seedlings contaminated with Cd and Cu for one month. In the ecosystem, the Cd concentration in wheat seedlings rose greatly with the increasing of Cd in the soil, but the Cu concentration in wheat seedlings was not found elevated. There was a highly significant difference（P〈0.05） in Cd concentrations of wheat seedlings and not any significant difference（P〉0.05） in Cu concentrations of wheat seedlings. The Cd and Cu concentration in different body part-head, thorax, abdomen, and hind femur, varied under different Cd concentrations in soil. There were significant differences （P〈0.05） in the four parts of Cd and Cu accumulations with all treatments. The order of Cd accumulation was thorax 〉abdomen 〉head 〉hind femur and the Cu was abdomen 〉thorax 〉 head〉hind femur. The results indicated that Cd and Cu were accumulated from the soil to grasshoppers through the plant; that is to say, Cd and Cu in environment could be transported to animal or human via food chain.

关键词： accumulation cadmium(Cd) copper(Cu) grasshopper(Oxya chinensisi) soil-plant-insect ecosystem

Puerarin prevents bone loss in ovariectomized mice and inhibits osteoclast formation in vitro

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Chinese Journal of Natural Medicines 2016年第4期14卷 265-269页

作者： YUAN Si-Yuan SHENG Tong liu Lian-Qi ZHANG Yun-Ling liu xue-mei MA Tao ZHENG Hong YAN Yan ISHIMI Yoshiko WANG Xin-Xiang School of Basic Medicine Sciences Beijing University of Chinese Medicine Beijing 100029China Dongfang Hospital Beijing University of Chinese Medicine Beijing 100029China National Institute of Health and Nutrition Tokyo 163-8001Japan

The present study aimed at investigating the effects of Puerarin(PR), a major isoflavonoid isolated from the Chinese medicinal herb Puerariae radix, on bone metabolism and the underlying mechanism of action. The in vivo assay, female mice were ovariectomized(OVX), and the OVX mice were fed with a diet containing low, middle, and high doses of PR(2, 4, and 8 mg·d^(-1), respectively) or 17β-estradiol(E_2, 0.03 μg·d^(-1)) for 4 weeks. In OVX mice, the uterine weight declined, and intake of PR at any dose did not affect uterine weight, compared with the control. The total femoral bone mineral density(BMD) was significantly reduced by OVX, which was reversed by intake of the diet with PR at any dose, especially at the low dose. In the in vitro assay, RAW264.7 cells were used for studying the direct effect of PR on the formation of osteoclasts. PR reduced the formation of tartrate resistant acid phosphatase(TRAP)-positive multi-nucleated cells in the RAW 264.7 cells induced by receptor activator for nuclear factor-κB Ligand(RANKL). MC3T3-E1 cells were used for studying the effects of PR on the expression of osteoprotegerin(OPG) and RANKL m RNA expression in osteoblasts. The expression of OPG m RNA and RANKL m RNA was detected by RT-PCR on Days of 5, 7, 10, and 12 after PR exposure. PR time-dependently enhanced the expression of OPG m RNA and reduced the expression of RANKL m RNA in MC3T3-E1 cells. In conclusion, our results suggest that PR can effectively prevent bone loss in OVX mice without any hyperplastic effect on the uterus, and the antiosteoporosis activity of PR may be related to its effects on the formation of osteoclasts and the expression of RANKL OPG in osteoblasts.

关键词： Puerarin Osteoporosis Ovariectomized mice Osteoblast Osteoclast

基于LS-SVM建模方法近红外光谱检测土壤速效N和速效K的研究

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光谱学与光谱分析 2012年第11期32卷 3019-3023页

作者：刘雪梅柳建设东华大学环境科学与工程学院上海201620 华东交通大学土木建筑学院江西南昌330013

应用可见/短波近红外光谱(Vis/SW-NIRS)测量土壤速效氮(N)和速效钾(K)含量。光谱预处理包括标准正态变换(SNV),多元散射校正(MSC)和Savitzky Golay平滑结合一阶导数,以消除系统噪声和外部干扰,分别应用偏最小二乘(PLS)和最小二乘支持向... 详细信息

应用可见/短波近红外光谱(Vis/SW-NIRS)测量土壤速效氮(N)和速效钾(K)含量。光谱预处理包括标准正态变换(SNV),多元散射校正(MSC)和Savitzky Golay平滑结合一阶导数,以消除系统噪声和外部干扰,分别应用偏最小二乘(PLS)和最小二乘支持向量机(LS-SVM)方法建立校正模型。最小二乘支持向量机(LS-SVM)输入分别包括主成分分析得到的主成分(PCs)和PLSR建模得到的潜在变量(LVs)和由PLSR模型回归系数得到有效波长(EWs)。结果表明,三种输入的LS-SVM模型都优于PLS模型,其中EWs-LS-SVM模型最佳,速效氮(N)的相关系数(R2)和预测均方误差RMSEP分别0.82和17.2,速效钾(K)为0.72和15.0。结果表明,利用可见光和短波近红外光谱(Vis/SW-近红外光谱)(325～1 075nm)的LS-SVM的结合,可以作为一个精确的土壤理化性质的测定方法。

关键词： LS-SVM 近红外漫反射光谱土壤速效氮速效钾

A Modified SOFM Method for Point Cloud Segmentation in Reverse Engineering

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Computer Aided Drafting,Design and Manufacturing 2005年第2期15卷 33-37页

作者： liu xue-mei ZHANG Shu-sheng BAI Xiao-liang Northwestem Polytechnical University Xi ＇an 710072 China North China Institute of Water Conservancy and Hydroelectric Power Zhengzhou 450008 China

The purpose of reverse engineering is to convert a large point cloud into a CAD model. In reverse engineering, the key issue is segmentation, i.e. studying how to subdivide the point cloud into smaller regions, where each of them can be approximated by a single surface. Segmentation is relatively simple, if regions are bounded by sharp edges and small blends; problems arise when smoothly connected regions need to be separated. In this paper, a modified self-organizing feature map neural network （SOFM） is used to solve segmentation problem. Eight dimensional feature vectors （3-dimensional coordinates, 3-dimensional normal vectors, Gaussian curvature and mean curvature） are taken as input for SOFM. The weighted Euclidean distance measure is used to improve segmentation result. The method not only can deal with regions bounded by sharp edges, but also is very efficient to separating smoothly connected regions. The segmentation method using SOFM is robust to noise, and it operates directly on the point cloud. An examples is given to show the effect of SOFM algorithm.

关键词： reverse engineering point cloud segmentation neural network self-organizing feature map

Cloning and Analysis Expression Patterns of Novel PPR Gene in Cotton

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Cloning and Analysis Expression Patterns of Novel PPR Gene i...