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Research on the method for retrieving soil moisture using thermal inertia model

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Science China Earth Sciences 2006年第5期49卷 539-545页

作者： LIU Zhenhua1 & ZHAO Yingshi2.1. Information college, South China agricultural {2., Guangzhou 510642. China 2. Graduate {2. of Chinese Academy of Sciences, beijing 100049, China 1. Information college South China Agricultural University Guangzhou 510642 China 2. Graduate university of Chinese Academy of Sciences Beijing 100049 China

In order to improve accuracy of soil moisture inversion using remote sensing, a new thermal inertia model is proposed in this paper. The improved model needs only surface maximum temperature as the temperature parameter input instead of input of the surface temperature difference, as well as the surface sensible and latent fluxes are introduced into boundary conditions of thermal conductivity equation. Furthermore, surface soil conductive heat transfer equation of two-layer model is used to solve the soil thermal inertia so that the remote sensing thermal inertia method can be ap- plied to regions with better-covered vegetation, but usually only for the bare areas or worse vegetation covered areas. The model has been tested at several locations in the area of west Inner Mongolia. Comparing the simulation of the new model with the measurements obtained by apparent thermal inertia and by field test, the result shows that the inertia thermal model can be used to estimate soil moisture in more reasonable accuracy.

关键词： thermal model, thermal conductivity equation, soil initial, sensible flux, latent flux, two-layer model.

Effect of physiological heterogeneity of E. coli population on antibiotic susceptivity test

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Science China(Life Sciences) 2007年第6期50卷 808-813页

作者： LIU YuQing1,3, ZHANG HuaiQiang2. SHEN JianZhong3 & GAO PeiJi2.1 Institute of Animal Science and veterinary medicine, Shandong Academy of {2. Science, Jinan 2.0100, China 2.State Key Laboratory of Microbial Technology, Shandong university, Jinan 2.0100, China 3 college of veterinary medicine, China {2. university, beijing 1.0094, China 1. Institute of Animal Science and veterinary medicine Shandong Academy of Agricultural Science Jinan 250100 China 3. college of veterinary {2. China Agricultural University Beijing 100094 China 2. State Key Laboratory of Microbial Technology Shandong University Jinan 250100 China

According to the instantaneous growth rate (dN/dt) of E. coli CVCC2.9 growing in batch culture, the entire growth progress was distinguished into four phases: accelerating growth phase, constant growth phase, decelerating growth phase; declining phase, in each of which obvious variation in physiological; biochemical properties was detected, including total DNA, total protein,; MTT-dehydrogenase activity, etc., that led to difference in their antibiotic susceptivity. Antibiotic susceptivity of the population sampled from each phase was tested by Concentration-killing Curve (CKC) approach following the formula N=N 0/{1+exp[r·(x-BC 50)]}, showing as normal distribution at the individual cell level for an internal population, in which the median bactericidal concentration BC 50 represents the mean level of susceptivity, while the bactericidal span BC 199=(2.nN 0)/r indicates the variation degree of the antibiotic susceptivity. Furthermore, tested by CKC approach, the antibiotic susceptivity of E. coli CVCC2.9 population in each physiological phase to gentamicin or enoxacin was various: susceptivity of the population in the constant growth phase; declining phase all increased compared with that in the accelerating growth phase for gentamicin but declined for enoxacin. The primary investigations revealed that the physiological phase should be taken into account in the context of antibiotic susceptivity; research into antimicrobial mechanism. However there are few reports concerned with this study. Further research using different kinds of antibiotics with synchronized continuous culture of different bacterial strains is required.

关键词： instantaneous growth rate, batch culture, physiological heterogeneity, concentration-killing curve, antibiotic susceptivity test

Neuroglobin mutation associated with hypoxia adaptation in Tibet chicken

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Progress in Natural Science:Materials International 2007年第12期17卷 1419-1424页

作者： Zhang Lifan1, Liu Chong2. Lian Linsheng3, Zhao Chunjiang1, Bao Haigang1 and Wu Changxin1(1. college of Animal Science and Technology, China agricultural {2., beijing 1.0094, China 2. college of Biological Science, China agricultural {2., beijing 1.0094, China 3. college of Animal Science and Technology, Yunnan agricultural {2., Kunming 6502.1, China) college of Animal Science and Technology China Agricultural University Beijing 100094 China college of Biological Science China Agricultural University Beijing 100094 China college of Animal Science and Technology Yunnan Agricultural University Kunming 650201 China

Globin protein family plays an important role in storing and transporting oxygen. As a newly reported globin, the revealed function of neuroglobin includes binding and storing oxygen as well as facilitating the utilization of oxygen in neuronal cells. In the present study, mutations in exons of chicken Ngb gene were identified with the method of sequencing and created restriction site PCR in Tibet chicken and other four lowland chicken breeds. The mutations of Lys-2.2.(E4)-Asn and Ser-2.79(E4)-Gly were identified in exon 4 of the gene. The Lys-2.2.(E4)-Asn mutation existed only in Tibet chicken and the mutation frequencies increased with increasing altitude. Analysis of the haplotype and diplotype of the two mutations in Tibet chicken populations of different altitudes showed that the frequencies of TG haplotype and TTGG diplotype also increased with increasing altitude, while the reverse tendency was found on GGAA diplotype. Under the hypoxic simulation incubation, the main haplotype was TG in living embryos and GA in dead embryos. The results showed that the Lys-2.2.(E4)-Asn mutation may be a specific mutation associated with hypoxia adaptation in Tibet chicken.

关键词： Tibet chicken neuroglobin hypoxia adaptation Ngb gene mutation.

Phototoxic effect of UVR on wild type, ebony and yellow mutants of Drosophila melanogaster: Life Span, fertility, courtship and biochemical aspects

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Science China(Life Sciences) 2008年第10期51卷 885-893页

作者： WANG ZhePeng1,2. LIU RuiFang2. WANG AnRu3, DU LiLi1 & DENG XueMei1 1 college of Animal Science and Technology, China agricultural {2., beijing 1.0094, China 2.Vocational and Technologic college, Inner Mongolia Agriculture {2., Baotou 014109, China 3 college of veterinary medicine, China agricultural {2., beijing 1.0094, China 1. college of Animal Science and Technology China Agricultural University Beijing 100094 China 2. Vocational and Technologic college Inner Mongolia Agriculture University Baotou 014109 China 3. college of veterinary {2. China Agricultural University Beijing 100094 China

Melanin plays an important role in protecting organisms from ultraviolet radiation (UVR). Therefore, it is possible that differently colored strains can show different sensitivities to UVR. In the present work, life span, fertility and courtship behavior of wild type (w), ebony (e) and yellow (y) strains of Drosophila melanogaster were studied to evaluate their sensitivity to ultraviolet (UV). Because a range of photo- toxic effects of UVR are mediated through generation of free radicals, levels of free radicals, lipid per- oxide (malondialdehyde, MDA) and superoxide dismutase (SOD) activity of three strains were examined to indicate their antioxidant defending ability and oxidative status. It was shown that w always had the highest lifespan and fertility not only in the control but also in UV-exposed groups. Moreover, lifespan and fertility of e were significantly higher (P2. effect on the SOD activities. After pooling data from the control and UV-exposed groups, we found that w had a significantly (P0.05). MDA levels were increased in the UV dose-dependent manner (P=0.0495). In con- clusion, our results suggested that UVR can decrease life span and fertility of flies and do harm to courtship, which may be due to oxidative damage to flies tissues (e.g. central nervous system) induced by free radicals. w had the highest tolerance to UVR, which may be ascribed to its advantage of survival under the natural condition and at high level of SOD activity. Then differences of pigment between e and y in absorbing UV, shielding agai

关键词： ultraviolet radiation Drosophila melanogaste free radicals pigment

The refined theory of deep rectangular beams based on general solutions of elasticity

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Science China(Physics,Mechanics & Astronomy) 2006年第3期49卷 291-303页

作者： GAO Yang1 & WANG Minzhong2.1. college of Science, China agricultural {2., beijing 100083, China 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engi- neering Science, Peking {2., beijing 100871, China college of Science China Agricultural University Beijing 100083 China State Key Laboratory for Turbulence Complex Systems Department of Mechanics Engineering Science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional the- ory for a homogeneous isotropic beam is investigated. Based on elasticity theory, the re- fined theory of rectangular beams is derived by using Papkovich-Neuber solution and Lur’e method without ad hoc assumptions. It is shown that the displacements and stresses of the beam can be represented by the angle of rotation and the deflection of the neutral surface. Based on the refined beam theory, the exact equations for the beam without transverse surface loadings are derived and consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beam under transverse loadings are derived directly from the refined beam theory and are almost the same as the governing equations of Timoshenko beam theory. In two ex- amples, it is shown that the new theory provides better results than Levinson’s beam the- ory when compared with those obtained from the linear theory of elasticity.

关键词： deep rectangular beams,the refined theory,Papkovich-Neuber solution,Lur'e method,governing equation

Identification of one peptide which inhibited infectivity of avian infectious bronchitis virus in vitro

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Science China(Life Sciences) 2006年第2期49卷 158-163页

作者： PENG Bo1, CHEN Hanyang1, TAN Yadi1,2. JIN Meilin1,2. CHEN Huanchun1,2.& GUO Aizhen1,2.1. Laboratory of Animal Virology, college of veterinary {2., Huazhong agricultural university, Wuhan 430070, China 2. National Key Laboratory of agricultural Microbiology, Huazhong agricultural university, Wuhan 430070, China 1. Laboratory of Animal Virology College of Veterinary Medicine Huazhong Agricultural University Wuhan 430070 China 2. National Key Laboratory of agricultural Microbiology Huazhong Agricultural University Wuhan 430070 China

Purified avian infectious bronchitis virus (IBV) was used to screen a random phage dis-play peptide library. After the fourth panning, 10 positive phages were sequenced and characterized. The phages specifically inhibited IBV infectivity in HeLa cells and blocked IBV haemagglutination. One linear peptide “GSH HRH VHS PFV” from the positive phages with the highest neutralization titer was synthesized and this peptide inhibited IBV infection in HeLa as well. The results may contribute to development of antiviral therapeutics for IBV and studying the determinants for viral and cell interac-tion.

关键词： avian infectious bronchitis virus, phage display, peptides.

The refined theory of transversely isotropic piezoelectric rectangular beams

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 473-486页

作者： GAO Yang1 & WANG Minzhong2.1. college of Science, China agricultural {2., beijing 100083, China 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engi- neering Science, Peking {2., beijing 100871, China 1. college of Science China Agricultural University Beijing 100083 China 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engineering Science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional theory for a transversely isotropic piezoelectric rectangular beam is investigated. Based on the piezoelasticity theory, the refined theory of piezoelectric beams is derived by using the general solution of transversely isotropic piezoelasticity and Lur'e method without ad hoc assumptions. Based on the refined theory of piezoelectric beams, the exact equations for the beams without transverse surface loadings are derived, which consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beams under transverse loadings are derived directly from the refined beam theory. As a special case, the governing differential equations for transversely isotropic elastic beams are obtained from the corresponding equations of piezoelectric beams. To illustrate the application of the beam theory developed, a uniformly loaded and simply supported piezoelectric beam is examined.

关键词： rectangular beams, the refined theory, piezoelectric, transversely isotropic.

Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science China Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2.3, WANG Pengxin4, YANG Hua1,2.3, LIU Shaomin1,2.3 & WANG Jindi1,2.3 1. Research Center for Remote Sensing and GIS, School of Geography, beijing Normal university, beijing 100875, China 2. State Key Laboratory of Remote Sensing Science, beijing 100875, China 3. beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, beijing 100875, China 4. Department of Information Management, college of Information and Electronic Engineering, China agricultural university, beijing 100083, China 1. Research Center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing 100875 China 2. State Key Laboratory of Remote Sensing Science Beijing 100875 China 3. beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing 100875 China 4. Department of Information Management College of Information and Electronic Engineering China Agricultural University Beijing 100083 China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

Determination of 2. β_2.agonists and 5 β-blockers in animal muscle by high performance liquid chromatography-linear ion trap mass spectrometry

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Science China Chemistry 2010年第4期53卷 832-840页

作者： WU YongNing1,2. MIAO Hong1, FAN Sai1,2.& ZHAO YunFeng1,2.1 Institute of Nutrition and Food Safety, Chinese Centre for Disease Control and Prevention, beijing 10002., China 2.college of {2. medicine, China agricultural university, beijing 100193, China 1. Institute of Nutrition and Food Safety Chinese Centre for Disease Control and Prevention Beijing 100021 China2. College of Veterinary Medicine China Agricultural University Beijing 100193 China

A high performance liquid chromatography-linear ion trap mass spectrometry method using isotope dilution technique has been developed for the simultaneous determination of 2. β2.agonists and 5 β-blockers in animal muscle tissues. Pork and chicken muscle samples were acid hydrolyzed and extracted with 5% trichloracetic acid in water, and then cleaned up using MCX solid phase extraction (SPE) cartridge. Methanol and 0.1% formic acid were used as mobile phases for gradient elution. A Waters AtlantisT3 column was used for separation. ESI positive ion scan mode was used with selective reaction monitoring. 9 β2.Agonists labeled by the deuterium isotope were used as internal standards for quantification. The linear ranges of 2. β2.agonists and 5 β-blockers were 5-2.0 μg/L, the coefficient of correlation was not less than 0.995, and the limit of detection for each compound in the muscle tissue was below 0.2.μg/kg. The recoveries of each compound in the spiked samples at three levels 5, 10, 2. μg/kg were in the range of 47.3%-12..7%, and the relative standard deviations were in the range of 3.2.-2..7%. The developed method is sensitive and specific for the determination of β2.agonists and β-blockers in pork and chicken muscle samples.

关键词： β2.agonists β-blockers muscle determination HPLC-ITMS