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数学学报（中文版） 1999年第4期42卷 583-590页

作者：范大山 csd.uwm.edu 陆善镇 *** 杨大春 *** 北京师范大学数学系

作者建立了一大类次线性算子和交换子在齐型空间上的Morrey空间中的有界性．应用这些结果，作者研究了具有不连续系数的超抛物方程解的局部正则性．

关键词：齐型空间 Morrey空间次线性算子有界性

Beta-Glucosidase Activity in Paddy Soils of the Taihu Lake Region, China

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Pedosphere 2006年第1期16卷 118-124页

作者： WANG Xiao-Chang LU Qin Department of Tea Science Zhejiang University Hangzhou 310029 （China）. Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）

The profile distribution of β-gulcosidase activity in twelve typical paddy soil profiles with high productivity in the Taihu Lake region of China were investigated. Activities of β-gulcosidase in the plow layers were in the range of 52.68- 137.02μg PNP g^-1 soil h^-1 with a mean of 89.22μg PNP g^-1 soil h^-1. However, most plow layers ranged from 70 to 110 μg PNP g^-1 soil h^-1. The profile distribution of β-gulcosidase activity in the 12 soil profiles decreased rapidly with soil depth, with activity at the 60 cm depth only about 10% of that in the surface layers （0-15 cm or 0-20 cm）. In these soil profiles, β-gulcosidase activity was significantly positively correlated with soll organic carbon and arylsulphatase activity. Meanwhile, a significantly negative correlation was shown between β-gulcosidase activity and soil pH.

关键词： beta-gulcosidase activity profile distribution paddy soil Taihu Lake region

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从“试验田”到“高产田”──也谈***的成功之道

电脑知识与技术 2000年第5期 4-5页

作者： cccc.edu cn

STOCHASTIC ANALYSIS OF UNSATURATED FLOW WITH THE NORMAL DISTRIBUTION OF SOIL HYDRAULIC CONDUCTIVITY

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Journal of Hydrodynamics 2003年第6期15卷 1-15页

作者： HuangGuan-hua. ZhangRen-duo FacultyofHydraulicandCivilEngineering ChinaAgriculturalUniversityBeijing100083China DepartmentofRenewableResources UniversityofWyomingLaramieWY82071-3354USA

Stochastic approaches are useful to quantitatively describe transportbehavior over large temporal and spatial scales while accounting for the influence of small-scalevariabilities. Numerous solutions have been developed for unsatu-rated soil water flow based on thelognormal distribution of soil hydraulic conductivity. To our knowledge, no available stochasticsolutions for unsaturated flow have been derived on the basis of the normal distribution ofhydraulic conductivity. In this paper, stochastic solutions were developed for unsaturated flow byassuming the normal distribution of saturated hydraulic conductivity (K_s). Under the assumptionthat soil hydraulic properties are second-order stationary, analytical expressions for capillarytension head variance (σ_h^2 ) and effective hydraulic conductivity (K_ii~*) in stratified soilswere derived using the perturbation method. The dependence of σ_h^2 and K_ii~* on soil variabilityand mean flow variables (the mean capillary tension head and its temporal and spatial gradients) andmean flow conditions (wetting and drying) were systematically analyzed. The calculated variance ofcapillary tension head with the analytical solution derived in this paper was compared with fieldexperimental data. The good agreement indicates that the analytical solution is applicable toevaluate the variance of capillary tension head of field soils with moderate variability.

关键词： stochastic analysis unsturated flow normal distribution soil hydraulicconductivity

On Extending Real Functions to Finite Dimensional Algebras

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Acta Mathematica Sinica,English Series 1999年第4期15卷 455-470页

作者： Bingren Li Institute of Mathematics,Academia Sinica,Beijing 100080,P.R.China E-mail:libr@sun.ihep,ac.cnYimin Yang Division of Science & Mathematics,University of Minnesota,Mcrros,MN 56276 U S A E-mail:yangy@mrs,umn.edu Institute of Mathematics Academia Sinica Beijing P. R. China Division of Science & Mathematics University of Minnesota Mcrros USA

In a finite dimensional real algebra,we define functional calculus for real *** analytic hypothesis is replaced by a differentiable *** order differentibility is essentially necessary and sufficient to our ***,we give... 详细信息

关键词： m-Extension Continuous derivative Characteristic polynomial

Leptin: a multifunctional hormone

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Cell Research 2000年第2期10卷 81-92页

作者： HUANG Lu, CAI LI(Tel: (214)-648-3340 Fax: (214)-648-9191 E-mail: li03@utsw.swmed.edu)(1 Touchstone Center for Diabetes Research1 Departments of Physiology and,2 Departments of Internal MedicineThe University of Texas Southwestern Medical Center5323 H. Touc hstone Center for Diabetes Research The University of Texas Southwestern Medical Center 5323 H. Hines Boulevard Dallas USA Departments of Physiology The University of Texas Southwestern Medical Center 5323 H. Hines Boulevard Dallas USA Department of Internal Medicine The University of Texas Southwestern Medical Center 5323 H. Hines Boulevard Dallas USA

Leptin is the protein product encoded by the obese (ob)gene. It is a circulating hormone produced primarily by the adipose tissue. ob/ob mice with mutations of the gene encoding leptin become morbidly obese, infertile, hyperphagic, hypothermic,and diabetic. Since the cloning of leptin in 1994, our knowledge in body weight regulation and the role played by leptin has increased substantially. We now know that leptin signals through its receptor, OB-R, which is a member of the cytokine receptor superfamily. Leptin serves as an adiposity signal to inform the brain the adipose tissue mass in a negative feedback loop regulating food intake and energy expenditure. Leptin also plays important roles in angiogenesis, immune function, fertility and bone formation. Humans with mutations in the gene encoding leptin are also morbidly obese and respond to leptin treatment,demonstrating that enhancing or inhibiting leptin's activities in vivo may have potential therapeutic benefits.

关键词： Leptin OB-R hypothalamus adipose tissue obesity diabetes cytokine receptor

Studies on rickettsia-like organism (RLO) disease of tropical marine pearl oyster-Epidemiological investigation of RLO disease in juvenile populations of maricultured Pinctada maxima

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Acta Oceanologica Sinica 2003年第3期22卷 421-435页

作者： Xinzhong Wu , Dengfeng Li, Jinpei Pan, Jingbo Jiang College of Animal Sciences,Zhejiang University,Hangzhou 310029,China. Email: wuxz@zju.edu.cnSouth China Sea Institute of Oceanology, Chinese Academy of Sciences,Guangzhou 510301,ChinaSchool of Life Sciences,SUN YAT-SEN University,Guangzhou 510275,China College of Animal Sciences Zhejiang University Hangzhou 310029 China South China Sea Inst. of Oceanology Chinese Academy of Sciences Guangzhou 510301 China School of Life Sciences SUN YAT-SEN University Guangzhou 510275 China

The death which occurred in juvenile population was a severe problem in the course ofPinctada maxima artificial culture. With the methods of field investigation, histological study and statistic analyses, the epidemiological study was carried out on the disease and death in juvenile populations of Pinctada maxima in the Xinying Pearl Oyster Mariculture Farm of Lingao County (for the A, B and C batches of cultured juveniles hanged in the sea) and the Xincun Pearl Oyster Mariculture Farm of Lingshui County (for the D batch of cultured juvenile hanged in the pond), Hainan Province from November 1993 to April *** results show that the deaths which occurred in juvenile populations of Pinctada maxima presented an outbreak pattern. The peak of mortality rates, in general, occurred in 4-to 6-month old pearl oyster juveniles, and the mortality rates gradully declined with the extention of pearl oyster age after cul-turing 8 months. The correlation between the mortality rates of juvenile populations and mean body lengths of juvenile populations show that the mortality rate become higher under 4 cm of mean body lengths of juvenile population and become obvious declined over 5 cm of mean body lengths. The peak of mortality rate occurred in 1-3 cm of mean body lengths. The results of histological observation showed that rickettsia-like organism inclusions were common, histological widespread infective agent among every batches (A, B, C and D) of cultured juvenile populations. The mean severity indices (SI) of rickettsia-like organism (RLO) infection were positively correlated with mortality rates of juvenile populations. After or within every peaks of RLO infection were all accompanied with the peaks of mortality rates of host populations and the mortality rates declined with decreased RLO infection. So the evidences of histological observation and epidemiology in this study indicated that rickettsia-like organism (RLO) may be as an important pathogenic organism of disease

关键词： Pinctada maxima rickettsia-like organism epidemiology juvenile population

A Minimizing Property of Lagrangian Solutions

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Acta Mathematica Sinica,English Series 2001年第3期17卷 497-500页

作者： Shi Qing ZHANG Department of Mathematics,Chongqing University,Chongqing 400044,P.R.China E-mail:abc98@cqu.edu.cnQing ZHOU Department of Mathematics,East China Normal University,Shanghai 200062,P.R.China E-mail:qzhou@*** Department of Mathematics Chongqing University Chongqing 400044 P. R. China Department of Mathematics East China Normal University Shanghai 200062 P. R. China

In this paper,we prove that the Lagrangian solutions to the three-body problem minimize the action function.

关键词： Three-body problem Lagrange solutions

Timing of Holocene sea-level highstands by mass spectro-metric U-series ages of a coral reef from Leizhou Peninsula, South China Sea

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Chinese Science Bulletin 2002年第4期47卷 348-352页

作者： ZHAO Jianxin & YU KefuDepartment of Earth Sciences, University of Queensland, Brisbane, Qld 4072, Australia (e-mail: j.zhao@earth.uq.edu.au) South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 501301, China (e-mail: kefuyu@scsi Department of Earth Sciences University of Queensland Brisbane Australia South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China

Systematic mass spectrometric 230Th ages are reported for a Ponies coral reef terrace from Dengloujiao, Leizhou Peninsula, South China Sea. Seven episodes of coral growth were recognized in this terrace: 7125±96, 6764±29, 5826±37, 5006±54, 2543±24, 1915±15, and 1513±22 calendar years before present (cal. aBP). 50% of the coral age popula-tion fall between 7200 and 6600 cal. aBP, marking post-glacial stabilization of global sea level. Considering the facts that (i) Dengloujiao reef flat was measured at 1.6-2.5 m above modern tidal datum plane; (ii) modern Parties corals in the South China Sea are living at least ~1 m below the modern tidal datum plane; (iii) the top 20-30 cm of the reef was eroded; and (iv) crustal subsidence in the region since mid-Holocene was negligible, we conclude that the above age groups record at least two major periods (7200-5000 and 2500-1500 cal. aBP) of high sea-level at least 2.9-3.8 m above the present-day level.

关键词： coral South China Sea U-series dating sea level Holo-cene.

Radio Observations of Sgr B2

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Chinese Journal of Astronomy and Astrophysics 2001年第5期1卷 406-410页

作者： XinJieMao Jiang－TaoSu ChineseAcademyofScience－PekingUniversityJointBeijingAstrophysicsCenter Beijing100087 DepartmentofAstr

The 13C0 (J 1 - 0) map of the molecular cloud Sgr B2 reveals that the mass center of the molecular cloud nucleus does not coincide with that of compact HII regions which are likely to be the outcome of a shock on the ... 详细信息

关键词： ISM: clouds - evolution - ISM: lines and bands