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Structural Analysis and Identification of Cis-Elements of Rice osRACD Gene

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Acta Biochimica et Biophysica Sinica 2004年第3期36卷 191-198页

作者： Yun-Zhe xu, Rui-Lin YOU and Nai-Hu WU institute of Genetics and Developmental Biology, chinese academy of sciences, beijing 100080, China 2College of Life sciences, Peking University, beijing 100871, China institute of Genetics and Developmental Biology Chinese Academy of Sciences College of Life sciences Peking University

The osRACD gene correlated with fertility transformation in the photoperiod sensitive genic male sterile rice (PGMR), Nongken 5.S, encoded a rice (Oryza sativa L. ssp. japonica) small GTPase belonging to the Rac/Rho family. Inverse PCR was performed to amplify a fragment about 1.4 kb in 5. upstream region of the osRACD promoter. Deletion mutation and gel mobility shift assay characterized two fragments (–799 to –686 nt, and –686 to –431 nt) in the osRACD promoter that could be involved in its transcriptional regulation. When these two deletion fragments were used as probe respectively, a retarded band appeared in the nuclear extracts of fertile 5.S rice under short day (5.S-SD). Whereas no retarded band was shown in the nuclear extracts of sterile 5.S rice under long day (5.S-LD). Competition assay indicated that the factors in the retarded bands binding to these two fragments were the same trans-acting factor (termed rice factor, RF). The binding affinity of RF was affected by phosphorylation and was higher in SD-growth rice than that of LD-growth rice.

关键词： photoperiod-sensitive male genic sterile rice osRACD gene photoperiod fertility transformation cis-element

On　the　Mechanism　of　Coal　Mine　Shaft　Damage　Caused　by　Subsidence　in　xuhuai　Area,Southeast　China

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Communications in Nonlinear Science and Numerical Simulation 1997年第2期2卷 19-22+24页

作者： Siwen BI, Xiangdong LOU + & Bing xu + (Department of geology, Peking University, beijing, of China) +(institute of geology {5. {5. of Science, People’s Republic of China) Department of geology Peking University Beijing 100871 China institute of geology Chinese Academy of Science Beijing China

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关键词： shaft damage caused subsidence numerical modeling

Climate as the dominant control on C_3 and C_4 plant abundance in the Loess Plateau: Organic carbon isotope evidence from the last glacial-interglacial loess-soil sequences

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chinese Science Bulletin 2003年第2期48卷 1271-1276页

作者： GU Zhaoyan, LIU Qiang, xu Bing, HAN Jiamao, YANG Shiling, DING Zhongli & LIU Tungsheng institute of geology and geophysics, chinese academy of sciences,{5., China Correspondence should be addressed to Gu Zhaoyan (e-mail: zgu@ ***) institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China

Abundance of C3 and C4 photosynthesis plants can be inferred relatively from stable carbon isotopic composi-tion of organic matter in soils. The samples from five sequences of the last glacial-interglacial loess-soil in the chinese Loess Plateau have been measured for organic carbon isotopic ratios (d 13Corg). The organic carbon isotope data show that relative abundance (or biomass) of C4 plants was increased ca. 40% for each sampling site from the last glacial maximum (LGM) to Holocene optimum, and increased southeastward on the Loess Plateau during both periods of LGM and Holocene. Statistic analyses on the steady maximum d 13Corg values of Holocene soils and modern climatic data from the Loess Plateau and Inner Mongolia indicate that the C4 plant abundance increases with increasing temperature and decreasing precipitation. The C4 plant abundance is related much closer with mean April tem-perature and precipitation than annual. These results lead us to deduce following conclusions. First, temperature is the major factor for control on variations in C4 plant abundance in the Loess Plateau from the last glacial to interglacial. In the absence of favorable temperature condition, both of low moisture and low atmospheric CO2 concentration are insufficient to drive an expansion of the C4 plants in the plateau. Second, d 13Corg in the loess-paleosol sequences, as a proxy of the relative abundance of C4 plants in the Loess Plateau, could not be used as an indicator of changes in the summer monsoon intensity unless the tem-perature had changed without great amplitude. Since all C4 plants are grasses, finally, the increase of the C4 plants supports that forest has not been dominant in the ecosystem on the Loess Plateau during Holocene although precipitation and atmospheric CO2 were largely increased relative to those during LGM.

关键词： C3/C4 plants d 13Corg Loess Plateau LGM Holocene.

GEOLOGICAL EVOLUTION AND OROGENY OF EAST KUNLUN TERRAIN ON THE NORTHERN QINGHAI—TIBET PLATEAU

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地学前缘 2000年第S1期7卷 234-235页

作者： xu Zhiqin, Yang Jingsui, Li Haibing(institute of geology, chinese academy of Geological {5., {5. 100037,China)

The East Kunlun terrain is located on the northern Qinghai—Tibet plateau, composed of the East Kunlun Mountain and the Qaidam Basin and bounded by the Qilian terrain on the north and Bayanhar—Songpan Ganze terrain on the south. It is regarded as a composite orogenic belt characterized by having developed superimposed ductile tectonic regimes reflecting the collision orogeny during Early Paleozoic and Triassic periods. It has also experienced transformation from ductile to brittle deformation caused by the post orogeny, since Jurassic after the formation of the East Kunlun Mountain and the Qaidam Basin. A Paleozoic subduction complex zone was recently recognized along the north border of the East Kunlun terrain from Da Qaidam to Dulan (xu,et al, 1 999). It is composed of ophiolite (of Early Paleozoic age?), tectonic melange and very high\|pressure metamorphic rocks with eclogite (\%p\%=2 2GPa, \%t\%=720℃) (Yang,et al.,1998) and garnet\|peridotite (\%p\%=2 5.Pa, t =837℃). The Anyemaqin Triassic subduction complex zone trending in NWW\|SEE was developed along the eastern segment of the south border of the East Kunlun terrain. It is mainly composed of ultramafic and mafic rocks, pillow basalt, radiolaria\|bearing clastic rocks, tectonic melange and mylonite. The subduction complex zone contains a series of the southward overthrusting imbricated slices. Instead of this subduction complex zone, a 2 km\|wide sinistral strike\|slip ductile shear zone trending in E\|W was developed along the western segment. On the basis of macroscopic and microscopic studies on a series of structural sections, we divide the East Kunlun Mountain into four tectonic units as follows: (1) North Proterozoic Metamorphic Basement Zone; (2) South Early Paleozoic—Triassic Superimposed Fold Zone; (3) South Triassic Transpression Zone; (4) Anyemaqin Back\|Arc Decollement\|Thrust Zone.

关键词： East Kunlun terrain composite orogenic belt subduction compl ex zone transpression shear zone

Chemical studies on alkaloids in the root of Acronychia oligophylebia Merr.

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chinese Journal of Chemistry 1984年第1期2卷 66-73页

作者： xu Wen-Hao xuE Zhi institute of Materia Medica,chinese academy of Medical {5.,beijing institute of Materia Medica Chinese Academy of Medical Sciences Beijing

Nine alkaloids and β-sitosterol were isolated from the root of Acronychia oi#gophylebia Merr.(Rutaceae).Among these alkaloids,five were identified as preskimmianine(2),evolitrine(5.,kokusaginine(6),skimmianine(7)and maculosidine(8).The alkaloids 2,5.and 8 wereisolated from Acronychia genus for the first ***(10)and oligophylidine(4)werenew bases,Oligophyline(3)and oligophylicine(9)were first found from natural *** spectroscopic data,the structures of 3,4,9 and 10 were *** structures of 10 and 9 wereconfirmed by synthesis.3 and 9 showed a wide spectrum of antifungal activity,but the actions were weak.

关键词： Chemical studies on alkaloids in the root of Acronychia oligophylebia Merr root

MORMALIZATION OF SUNSPOT CYCLES AND EIGEN MODE ANALYSIS

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MORMALIZATION OF SUNSPOT CYCLES AND EIGEN MODE ANALYSIS

Primary Study on Quantitative Reconstruction of Middle-Late Eocene Climate in Jianghan Basin

中国科学院地质与地球物理研究所2002学术年会

作者： xu Wen-Yao institute of geology and geophysics,chinese {5. of {5.,beijing,100101

In this paper the smoothed monthly sunspot numbers of the previous 22 complete sunspot cycles are normalized in time domain,and then an eigen mode analysis is carried out for drawing the principle factors(or components) in the *** results show that the main characteristics of the solar cycles can be fairly well described by the first 5.eigen *** obtained eigen modes are applied to predict the declining phase of cycle 23 on the basis of the data prior to its *** prediction indicates that cycle 23 will continue for 127 months to December 2006,with the minimum of 6.2.

关键词： sunpot solar cycle eigen mode analysis prediction of solar activity

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Journal of China University of Geosciences 2002年第3期13卷 252-259页

作者： Tong Guobang Liu Zhiming institute of Hydrogeology and Environmental geology, chinese academy of Geological {5., Zhengding 05.803 Open Laboratory of Saline Lake Resources and Environment, chinese academy of Geological {5., beijing 100037 Zheng Mianping institute of Mineral Resources, chinese academy of Geological {5., beijing 100037 Research & Development Center of Saline Lake and Epithermal Deposit, chinese academy of Geological {5., beijing 100037 Wang Weiming Nanjing institute of geology and Palaeontology, chinese academy of sciences, Nanjing 210008 institute of Hydrogeology and Environmental geology Chinese Academy of Geological Sciences Zhengding 050803 Open Laboratory of Saline Lake Resources and Environment Chinese Academy of Geological Sciences Beijing 100037 institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 Research & Development Center of Saline Lake and Epithermal Deposit Chinese Academy of Geological Sciences Beijing 100037 Nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing 210008

This paper reports our primary effort in the quantitative reconstruction ofpaleoclimate based on the thrine in phytoecology of the affinity parent plants in the stratigraphicpollen records. The Eocene pollen data come from our former study on the Mingjia borehole 1 in theJianghan basin. The fluctuating trend in the parameter curve of climate shows that the climate inthe Middle Eocene in the Jianghan basin was more or less comparable with that of the present22°―26°N, characteristic of a humid, semi-humid central-southern subtropical climate. The annualtemperature at that time dropped by 1 ℃― 4 ℃ in the Late Eocene, approximately equal to that ofthe present 23°―28°N of northern-central subtropical climate. However, the climate composite atthat time, characterized by higher temperature, small annual range and big fluctuation inprecipitation, was quite different from the present one. The average temperature in January in theMiddle Eocene, higher than that of today, ranged between 5.℃ and 9 ℃, indicating that no effect ofwinter monsoon occurred in the Middle Eocene, though such an effect may have occurred occasionallyin the Late Eocene. Major temperature decline is recognized at the depth of 2 100 m in the borehole,as was indicated by the decline in average January temperature, the increase in annual range, andthe increase in the deciduous broad-leaved types of trees in the spore-pollen assemblage. The sharpfluctuation in the annual precipitation, usually raging from 300 to 1 700 mm, was favorable for themigration and accumulation of salty deposit. When the precipitation was lower than 1 000 mm,ephemera shrub increased at the same depth as that of the salty deposit. It is, therefore, deducedthat the formation of the salty deposit was attributed mainly to the dry and hot environment in thehigh mountains and deep basins. The small annual precipitation and the intense fluctuation arefavorable for the sustainable accumulation of the salts, which is different from the present

关键词： quantitative reconstruction of paleoclimate annual range function ofthrine in phytoecology fuzzy mathematics eocene jianghan basin

geology and Geochemistry of Maoling Gold Deposit, Gaixian, Liaoning Province

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Journal of Earth Science 1999年第1期18卷 90-92页

作者： Qin Dajun Cai Xinping Wan Jie xu Xingwang Zhang Baolin institute of geology, chinese academy of sciences, beijing 1.0029

Maoling gold deposit is hosted in the Second Member of Gaixian Formation, which is mainly phyllonitized sericite phyllite with interbed sericite quartzite. Four altered zones with gold mineralization are delineated. Gold is mainly hosted in arsenopyrite, pyrrhotite, pyrite and minor in galena and quartz. Ore δ ( 34 S) is characterized by concentrating heavy sulfur. δ ( 18 O) and δ (D) of fluid inclusions in quartz have the same ranges as those in wall rocks, suggesting that metamorphic hydrothermal solution and meteoric water may be involved in the formation of the deposit. Moreover, deep faults and that some deep derived ore forming materials seem to play more important role.

关键词： mineralization metallogeny Maoling gold deposit.

Formation of Glycidyl Methacrylate-DNA Adducts in vivo

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Biomedical and Environmental sciences 1999年第2期12卷 95-102页

作者： FANG FU-DE LEI HAI-XIN ZUO JIN TAN MING-JIA AND xu JIAN-NING (institute of Basic Medical sciences, chinese academy of Medical Scicnces,{5. 100005. China Instituse of Occupational Medicine, chinese academy of Preverntive Medicine, {5. 10005., China) 中国医学科学院基础医学所北京 100005 中国预防医学科学院职业病医学所北京 100050 中国医学科学院基础医学所北京中国预防医学科学院职业病医学所北京

In in vivo test, rats were orally administrated with glycidyl methacrylate (GMA) at respective doses of 25. mg/kg, 125.mg/kg and 62. 5.mg/kg, 31. 25.mg/kg and solvent as control for 14 days. DNA adducts produced in the liver, kidney, blood and testis were analyzed by RP-HPLC and nuclease P1 mediated 32 P-postlabelling method. Results showed that several potential GMA-DNA adducts were formed in various organs (4 adducts in blood, 3 adducts in liver and kidney, 1 adduct in testis). A linear dose-response relationship was observed within certain dose levels. The relative adduct labeling values failed to further increase any more when the concentration went up to 125.mg/kg. The order of adduct level with GMA was kidney, liver, blood and testis. The GMA adduct N3methacrylate-2-hydroxypropyl-dCMP was found in kidney, liver and blood. These results indicated that GMA could react with negatively charged centers on DNA and form GMA-DNA adducts. If carcinogerrinduced DNA damage exceeds the ability of repair systems, gene mutation is ***, study on molecular mechanism of gene mutation induced by DNA adducts is not only an important part of chemical-carcinogenesis, but also provides information on critical biomarkers for monitoring human exposure to genetic toxins.

关键词： Animals Carcinogens DNA Adducts DNA Damage DNA Repair Dose-Response Relationship Drug Epoxy Compounds Male Methacrylates Mutagenesis Phosphorus Radioisotopes Rats Rats Wistar Research Support Non-U.S. Gov't