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1Reconstruction of precipitation variation from tree rings in recent 1000 years in Delingha, Qinghai显示文摘Using seven well-replicated Qilian juniper (Sabina przewalskii Kom.) ring-width chronologies developed at Zongwulong and Shalike Mts. in the northeastern part of the Qaidam Basin annual precipitation from previous July to current June in the recent 1000 years was re- constructed for Delingha. The reconstruction can capture 63.1% of precipitation variance and the equation was stable over time. For the reconstructed precipitation, wet periods occurred in AD1520—1633 and 1933—2001, whereas dry intervals in 1429—1519 and 1634—1741. In ad- dition, the magnitude in precipitation variation was lower before 1430 with about 15 mm, but it increased to 30 mm during the period of 1430 to 1850. After 1850, the precipitation variance de- creased again. In contrast to the increase in temperature, a decrease in annual precipitation was evident since the 1990s. The agreement in low-frequency variation between the reconstruction and the glacier accumulation and particulate content in Dunde ice cores during the recent several hundred years suggested that the precipitation reconstructed in this study was rather reliable, and represented a regional signal. This 1000-year reconstruction could benefit our understanding of climatic variation in decadal to century-scale in this region, and provide basic data to climate models and to prediction of future climate in the 21st century.SHAO Xuemei1, HUANG Lei1, LIU Hongbin2, LIANG Eryuan1, FANG Xiuqi3 & WANG Lili1 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2. National Climate Center, Beijing 100081, China 3. Beijing Normal University, Beijing 100875, China 2005Science China Earth Sciences2005,48,7:113
2Mesozoic subduction-accretion zone in northeastern South China Sea inferred from geophysical interpretations显示文摘A segment of Mesozoic subduction-accretion zone was inferred across the northeastern South China Sea at approximately NE45° orientation. Basic evidence includes the following: A belt of peek gross horizontal Bouguer gravity gradient (PGHGBA) is comparable in size and intensity to that of the Manila subduction-accretion zone. A belt of high positive magnetic anomalies appears to the north and sub-parallel to the PGHGBA, representing the volcanic arc associated to the subduction zone. The PGHGBA crosses obliquely both Cenozoic structures and present seafloor topography, indicating a pre-Cenozoic age. The segment is offset left-laterally by NW-running strike-slip faults, in concord with the Mesozoic stress field of South China. In addition, the existence of the subduction zone is supported by wide-angle seismic data obtained in different years by different institutions. At approximate localities, a north-dipping ramp of Moho surface is indicated by records of ocean-bottom seismometers, and a strong reflector about 8 km beneath the Moho reflector is indicated by both OBS and long-cable seismic records. The identification of a segment of Mesozoic subduction zone in NE South China Sea fills nicely the gap of the Great Late Mesozoic Circum SE Asia Subduction-acrretion Zone, which extended from Sumatra, Java, SE Kalimantan to N Palawan, and from Taiwan, Ryukyu to SW Japan.ZHOU Di1, WANG Wanyin2, WANG Jialin3, PANG Xiong4, CAI Dongsheng5 & SUN Zhen1 1. Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guang- zhou 510301, China 2. College of Geological and Topographical Engineering, Chang’an University, Xi’an 710054, China 3. Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China 4. China National Offshore Oil Co. Limited – Shenzhen Branch, Shenzhen 518067, China 5. China National Offshore Oil Co. Limited – Research Center, Beijing 100027, China 2006Science China Earth Sciences2006,49,5:52
3Contemporary crustal movement of continental China obtained by global positioning system(GPS) measurements显示文摘We obtain a unified horizontal velocity field of continental China and vicinity through measurements at 81 GPS stations provided by the National Key Infrastructure Project, Crustal Movement Observation Network of China. The velocity field delineates patterns of movements and deformation of active crustal blocks in continental China under the Eurasia-fixed reference frame. The space-based geodesy also clearly shows for the first time the horizontal movementand deformation of continental China induced by indentation of the Indian plate. The data provide kinematic constraints for simulating dynamic process of continental litho-spheric deformation.MA Zongjin, CHEN Xinlian, YE Shuhua, LAI Xian, WEI Ziqing, CHEN Junrong, NING Jinsheng, XU Huoze & DING Guoyu1. Insitute of Geology, China Seismological Bureau, Beijing 100029, China (e-mail: disgroup@publi.bta.net.cn)2. Center for Analysis and Prediction, China Seismological Bureau, Beijing 100036, China 3. Shanghai Astronomic Observatory, Chinese Academy of Sciences, Shanghai 200030, China 4. Institute of Seismology, China Seismological Bureau, Wuhan 430077, China 5. Institute of Survey and Mapping, Xi’an 710054, China 6. National Bureau of Survey and Mapping, Beijing 100830, China 7. Wuhan University, Wuhan 430077, China 8. Institute of Geodesy and Geophysics, Wuhan 430077, China 9. China Seismological Bureau, Beijing 100036, China 2001Chinese Science Bulletin2001,46,18:34
4Early J_2 basalts in SE China:Incipience of large-scale late Mesozoic magmatism显示文摘Magmatism in SE China was dormant during 204―180 Ma, but was reactivated in 180― 170 Ma (early J2), and then became more and more intensive towards the end of early Cretaceous. The small-scale early J2 magmatism is the incipience to long-term and large-scale magmatism in this region. A near east-west (EW) trend volcanic belt was distributed across south Hunan, south Jiangxi and southwest Fujian was formed during early J2 time. Along this belt from the inland toward the coast, the lithology of basalts changes from alkali into tholeiite, and the amount of erupted volcanic rocks and the proportions of rhyolites coexisting with the basalts increase. On the basis of geochemical char- acteristics of these basalts, we infer that the melting degree of source rocks and the extent of frac- tional crystallization and crustal contamination all increased whereas the depth of mantle source de- creased from the inland to the coast, which led to the variations of geological characteristics of the volcanic belt. In early J2, the western spreading Pacific plate began to subduct underneath SE China continental block, reactivating near EW trend deep fault that was originally formed during the Indos- inian event. The stress of the western spreading Pacific plate and the extent of asthenosphere up- welling increased from the inland to the coast, which is consistent with the generation and evolution of early J2 basalts.XIE Xin1, XU Xisheng1, ZOU Haibo2, JIANG Shaoyong1, ZHANG Ming3 & QIU Jiansheng1 1. State Key Laboratory of Mineral Deposit Research, Department of Earth Sciences, Nanjing University, Nanjing 210093, China 2. Department of Earth and Space Sciences, University of California at Los Angeles, Los Angeles, CA90095-1567, USA. 3. GEMOC ARC National Key Centre, Department of Earth and Planetary Sciences, Macquarie University, Sydney, N.S.W. 2109, Australia 2006Science China Earth Sciences2006,49,8:30
5The Y.D.and climate abrupt events in the early and middle Holocene:Stalagmite oxygen isotope record from Maolan,Guizhou,China显示文摘The isotope records which range from 3.9 kaBP to 15.7 kaBP with an average resolution of 90 a have been obtained from 45 cm to 193.6 cm of the upper part of D4 stalagmite from Dongguo Cave in Libo, Guizhou, by using system TIMS U-series dating and carbon and oxygen stable isotope analyses.The study indicates that the last cold event, the YD (Younger Dryas) event, of the last glacial period was apparently shown in D4 record, which started from 12.80 kaBP and ended in 11.58 kaBP, with a great range of drop in temperature. The end of the last glacial period was consistent with the termination I in oceanic isotope records and was with time limit of 11.3 kaBP. The three most distinct cold events in the early and middle Holocene occurred respectively in 10.91 kaBP, 8.27 kaBP and 4.75 kaBP, with a range of drop in tem- perature reaching 2—5℃. The climate abrupt events in thousand and hundred years scale re- corded in stalagmite δ O can be compared to those in GISP2 ice cores from Greenland in their 18 happening time and the range of their lasting time. The cold events in 8.27 kaBP and 4.75 kaBP can also be compared to CC3 stalagmite records in Ireland, which indicate that climate changes of short range in China monsoon areas, western Europe and polar regions, have the same driv- ing factor. This has a global significance. In addition, the trend of record curves in some time- stages is apparently different, which reflects probably the difference between environment in monsoon climate areas and in polar regions.QIN Jiaming1, YUAN Daoxian1, CHENG Hai2, LIN Yushi1, ZHANG Meiliang1, WANG Fuxing1, R. L. Edwards2, WANG Hua1 & RAN Jingcheng3 1. The Karst Dynamic Laboratory, IKG, CAGS, Guilin 541004, China 2. Geology and Geophysics Department, Minnesota University, MN55455, USA 3. The Management of Maolan National Nature Reserve, Libo 558400, China 2005Science China Earth Sciences2005,48,4:23
6Re-Os age for molybdenite from the Gangdese porphyry copper belt on Tibetan plateau: Implication for geody- namic setting and duration of the Cu mineralization显示文摘The Gangdese porphyry copper belt consists of one large and five middle-small deposits in addition to dozens of ore-bearing porphyry bodies. The belt trends 350 km long along the EW-striking Gangdese batholith, and locally occurs as a string of beads extending about 50 km within the SN-trending rifting zones (grabens) on the Tibetan plateau. Monzonitic granite- porphyry and quartz monzonitic porphyry, as dominant host rocks, are shoshonitic and potassic calc-alkaline. Available dating data indicate that the ages of the shallow-level emplacement for these porphyries vary from 10 Ma to 18 Ma, which are identical to that of associated potassic calc-alkaline volcanic rocks (10—15 Ma) and mafic dykes (13—18 Ma). The timing and duration of Cu mineralization events are constrained by Re-Os ages for molybdenites from three porphyry copper deposits in the Gangdese porphyry copper belt. Five molybdenite samples from the Nanmu deposit yielded an 187Re-187Os isochron with a highly pre-cise age of (14.76?.22) Ma; six molybdenites from the Chongjiang deposit gave an isochron age of (14.04?.16) Ma. Re-Os model ages for two molybdenite samples from Lakang抏 deposit vary from 13.5 Ma to 13.6 Ma, which are basically identical to isochron ages mentioned above. All the thirteen samples from these three deposits yielded a linear array in the isochron diagram with a higher correlation coefficient of 0.99719 and an isochron age of (14.39?.22) Ma (1s error), suggesting an coeval event of the Cu mineralization and a shared source of ore materials for the Gangdese porphyry copper belt. Compared with the longer-lived felsic magmatic-hydrothermal system, the Cu mineralization is a relatively short event with duration of about 0.5 Ma, and usu-ally occurs in the later-stage of the complicate magmatic system. The emplacement age of the Gangdese porphyries indicates that they intruded after the rapid rising of the Gangdese Mountains at 21—23 Ma, and formed in a post-collision crustal ex-tension environment. Constraint of the NS-trending rifting zones (grabens) on localization of these porphyry bodies implies that the minor east-west stretching dates back to approximately 18 Ma. Highly precise Re-Os age of the Cu mineralization event indicates that a significant east-west extension has commenced at about (14?.5) Ma ago, which is identical to that of the normal faulting in central Tibet (13.5 Ma) and southern Tibet (14 Ma). The strong extension not only provided dilatant conduits for the migration and emplacement of the porphyry magmas pooling near the base of lithosphere, but also resulted in the rapid rising of a large volume of volatile, thus in turn constraining the temporal-spatial localization of the Gangdese porphyry Cu belt.HOU Zengqian1, QU Xiaoming1, WANG Shuxian2, DU Andao2, GAO Yongfeng3 & HUANG Wei4 1. Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 100037, China 2. National Center of Geoanalysis, Chinese Academy of Geological Sciences, Beijing 100037, China 3. Shijiazhuang College of Economy, Shijiazhuang 056000, China 4. Xizang Bureau of Geology and Mineral Resources, Lhasa 850000, China 2004Science China Earth Sciences2004,47,3:18
7Applications of functionalized ionic liquids显示文摘Recent developments of the synthesis and applications of functionalized ionic liquids (including dual-functionalized ionic liquids) have been highlighted in this review. Ionic liquids are at-tracting attention as alternative solvents in green chemistry, but as more functionalized ILs are pre-pared, a greater number of applications in increasingly diverse fields are found.LI Xuehui1, ZHAO Dongbin2,3, FEI Zhaofu2 & WANG Lefu1 1. Department of Chemical Engineering, Guangdong Provincial Laboratory of Green Chemical Technology, South China Uni-versity of Technology, Guangzhou 510641, China 2. Swiss Federal Institute of Technology, Lausanne, EPFL, CH-1015 Lausanne, Switzerland 3. PKU Green Chemistry Center, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China 2006Science China Chemistry2006,49,5:18
8Re-Os(ICP-MS)dating of the massive sulfide ores from the Jinchuan Ni-Cu-PGE deposit显示文摘Massive sulfide ore from the Jinchuan Ni-Cu-PGE deposit was dated by Re-Os technique using Carius Tube digestion, Os distillation, Re extraction by acetone and ICP-MS measurement. An isochron giving an age of 833 ± 35 Ma, initial 187Os/188Os ratio of 0.279 ± 0.018 (MSWD = 1.7) and γOs = 130 ± 15 is obtained. The Re-Os age obtained agrees, within analytical uncertainties, with previous SHRIMP zircon U-Pb age of 827 ± 8 Ma (n=5, MSWD = 4.3). The result suggests that the deposit was formed at Neoproterozoic and that the formation of the Jinchuan Ni-Cu-PGE sulfide deposit may be closely related to the plume activity, which were attributed to the breakup of the Rodinia supercontinent. The high γOs of the massive ores sug-gests that crustal material was involved in the formation of the Jinchuan deposit, however, the quantity of the added crustal material is less than 10%.YANG Gang1,2, DU Andao1, LU Jiren3, QU Wenjun1 & CHEN Jiangfeng2 1. National Research Center of Geoanalysis, Beijing 100037, China 2. Laboratory for Earth Material Cycling, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China 3. Institute of Mineral Resource, Chinese Academy of Geological Sciences, Beijing 100037, China 2005Science China Earth Sciences2005,48,10:17
9Radiometric cross-calibration of the CBERS-02 CCD camera with the TERRA MODIS显示文摘For the application of the CCD camera, the most important payload on CBERS-02, the key is to provide long-term stable radiometric calibration coefficients. Although the vicarious calibration had been proved successful, it had its limitations such as test site requirement and unsuitable for historical data. Cross-calibration is one of the alternative methods, but it needs synchro surface spectrum to achieve spectral band matching factors. Our effort is to probe the influences on these factors. Simulations with a lot of surface spectrum showed that the factors changed with the viewing geometry, atmospheric condition and surface targets. However, simulating with the same viewing geometry and atmospheric condition, the spectral band matching factors of the same or similar surface targets’ spectrum acquired from different dates and different places would like to be consistent to each other within 1%―5%. Thus, the synchro measurement data can be substituted by the same or similar target from other source. Based on this method, using the MODIS as the reference, the cross-calibration was performed for CCD camera. The research demonstrated that the traditional method with single calibration site was inappropriate for CCD camera, since the offsets for its four spectral bands were not zeros. With four calibration sites, these offsets were obtained. And the camera was detected to degrade with dates based on four times of cross-calibrations.LI Xiaoying1,2,3, GU Xingfa1,3,4, MIN Xiangjun5, YU Tao1,3, FU Qiaoyan5, ZHANG Yong1,2,3 & LI Xiaowen1,3 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101, China 2. Graduate University of Chinese Academy of Sciences, Beijing 100039, China 3. The Center for National Spaceborne Demonstration, Beijing 100101, China 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. China Center for Resource Satellite Data and Application, Beijing 100830, China 2005Science China(Technological Sciences)2005,48,S2:15
10Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils显示文摘Studies show positive shifts of inorganic and organic carbon isotope values (δ 13Ccarb and δ 13Ckerogen) from +0.43 (‰ V-PDB) to +3.54 (‰ V-PDB) and from ?29.38 (‰ V-PDB) to ?24.14 (‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2O3 X 15%)) values from 0.015 to 0.144, TOC values from 0.02% to 0.21%, V/Cr values from 0.3 to 2.0, Sr/Ba values from 3.20 to 49.50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South China, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2, climatic cooling and sea level falling caused by eutrophication, anoxia and organic carbon burial increasing may be important for the mass extinction.GONG Yiming1,2, XU Ran1, TANG Zhongdao1, SI Yuanlan3 & LI Baohua4 1. Faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan 430074, China 2. Institute of Resources & Environments, Henan Polytechnic University, Jiaozuo 454003, China 3. Department of Computer Science, South-Central University for Nationalities, Wuhan 430074, China 4. Laboratory of Marine Geology, Tongji University, Shanghai 200092, China 2005Science China Earth Sciences2005,48,10:13
11Relationship between petroleum hydrocarbon and plankton in a mesocosm experiment显示文摘A mesocosm experiment was carried out from May 26 to June 1, 1998 at the location of 30’52’N, 122’36’E, the Changjiang Estuary, in order to measure the influence of petroleum hydrocar- bon to the ecosystem, furthermore, to estimate the environmental capacity. In the experiment, it is found that the petroleum hydrocarbon can, in some degree, enhance the growth of diatom, but inhibit the growth of dinoflagellate. In general, the petroleum hydrocarbon can inhibit the growth of both Phytoplankton and zooplankton, and can the inhibit the growth of total plankton (including phytoplankton and zooplankton) as well. A kinetic model was presented to estimate the uptake/release rate constants of petroleum hydrocarbon by plankton, and thereafter, the uptake and release rate constants (k1, k2), bioconcentration factor (BCF) as well as the petroleum bydrocarbon influenced influenced uptake and release rate constants of nutrients by phytoplankton (kup, krel) were obtained. The results imply that the bioconcentration of petroleum hydrocarbon by plankton is fairly large and petroleum hydrocarbon caused no significant influence on the uptake of N- NO3, but significant influence on that of P -PO4. In addition, the application of kinetic model for the bioconcentration of volatile organic toxic compound by organism suggests that the uptake of petroleum hydrocarbon by plankton was an important process for the environmental capacity of petroleum hydrocarbon.Shi Xiaoyong, Wang Xiulin, Han Xiurong, Jiang Yu Zhu Mingyuan, Chen Shang, Koshikawa Hiroshi (1. Ocean University of Qingdao, Qingdao 266003, China 2. First Institute of Oceanology, Qingdao 266061, China 3. National Institute for Environmental Studies, Ja 2001Acta Oceanologica Sinica2001,20,2:12
12Possible mechanism of the effect of convection over Asian-Australian “land bridge” on the East Asian summer monsoon onset显示文摘The Asian-Australian “land bridge” is an area with the most vigorous convection in Asian monsoon region in boreal spring, where the onset and march of convection are well associated with the onset of East Asian summer monsoon. The convection occurs over Indo-China Peninsula as early as mid-April, which exerts critical impact on the evolution of monsoon circulation. Before mid-April there are primarily sensible heatings to the atmosphere over Indo-China Peninsula and Indian Peninsula, so the apparent heating ratios over them decrease with height. However, after mid-April it changes into latent heating over Indo-China Peninsula due to the onset of convection, and the apparent heating ratio increases with height in mid- and lower troposphere. The vertical distribution of heating ratio and its differences between Indo-China Peninsula and Indian Peninsula are the key factors leading to the splitting of boreal subtropical high belt over the Bay of Bengal. Such mechanism is strongly supported by the fact that the evolution of the vertical heating ratio gradient above Indo-China Peninsula leads that of 850 hPa vorticity over the Bay of Bengal. Convections over Indo-China Peninsula and its surrounding areas further increase after the splitting. Since then, there is a positive feedback lying among the convective heating, the eastward retreat of the subtropical high and the march of monsoon, which is a possible mechanism of the advance of summer monsoon and convection from Indo-China Peninsula to South China Sea.HE Jinhai1, WEN Min2, DING Yihui3 & ZHANG Renhe2 1. Jiangsu Key Laboratory of Meteorological Disaster (KLME), Nanjing Institute of Meteorology, Nanjing University of Informa- tion Science and Technology, Nanjing 210044, China 2. State Key Laboratory of Severe Weather (LaSW), Chinese Academy of Meteorological Sciences, Beijing 100081, China 3. National Climate Center, Chinese Meteorological Administration, Beijing 100081, China 2006Science China Earth Sciences2006,49,11:10
13Morphology and mapping analysis of rice(Oryza sativa L.)clustered spikelets(Cl)mutant显示文摘The rice clustered spikelets (Cl) mutant exhib-its a phenotype that most of branch apical have 2-3 spikelets clustered together. SEM (scanning electron microscope) ob-servation suggested that the Cl gene controlled branch apical development, and influenced the terminal spikelets elonga-tion. The spikelet number was reduced in mutant, indicating that Cl may also have an effect on spikelet number. To map Cl locus, two F2 mapping populations derived from the crosses between the Cl and ZhongHua11, and Cl and ZheFu802 were constructed, respectively. The Cl locus was roughly mapped between two CAPS markers, CK0214 and SS0324. A further fine mapping analysis showed that the Cl locus was mapped between makers R0674E and Cl2560, with genetic distances of 0.2 and 2.1 cM, respectively. Then we found a PAC contig spanning Cl locus, the region was delim-ited to 196 kb. This result was useful for cloning of the Cl gene. Allelism test demonstrated that Cl was allelic to Cl2, another rice clustered spikelets mutant.ZHENG Leiying1, ZHU Xudong2, QIAN Qian2, ZHAO Zhong1, ZHANG Jianjun3, HU Xiaohe1, LIN Hongxuan1,4 & LUO Da1 1. National Key Laboratory of Plant Molecular Genetics, Shanghai In-stitute of Plant Physiology and Ecology, Chinese Academy of Sci-ences, Shanghai 200032, China 2. China National Rice Research Institute, Hangzhou 310006, China 3. Crop Institute of Breeding and Cultivation, Shanghai Agricultural Academy, Shanghai 201106, China 4. Shanghai Anxin Research Foundation Laboratory, Shanghai 200032, China 2003Chinese Science Bulletin2003,48,6:10
14Anti-inflammatory and Analgesic Effects of Extract from Roots and Leaves of Citrullus lanatus显示文摘Objective To study anti-inflammatory and analgesic effects of extract from the roots and leaves of Citrullus lanatus and assess their acute toxicity in animals. Methods The mouse model with ear edema induced by xylene and the rat model with paw edema or granuloma by carrageenin or cotton pellet were used for anti-inflammatory effects of the extract. Effects of the extract on analgesia was tested respectively by measuring the latency of mice licking hind foot from hot plates and by counting the times of body twisting in response to acetic acid. The acute toxicity of the extract was determined with the method of Bliss. Results The extract significantly inhibited the ear edema, granuloma hyperplasia, and paw edema. It significantly lifted the pain threshold on mouse hot-plate responses and reduced their writhing times. During the 7 d observation period in its acute toxicity assay, no apparent toxic reaction was shown and all mice survived at a dose of 87 g extract per kg body weight. Conclusion The extract could protecte mice/rates from inflammation and analgesia, and may be safe as an orally administered natural product for humans.DENG Jia-gang1, WANG Shuo2, GUO Li-cheng3, FAN Li-li1 1. Guangxi Traditional Chinese Medical University, Nanning 530001, China 2. The Key Laboratory of Academician YAO Xin-sheng, Guangxi Institute of Guangxi Medicinal Plant, Nanning 530023, China 3. Institute of Guangxi National Medicine, Guangxi Nanning 530023, China 2010Chinese Herbal Medicines2010,2,3:9
15Evaluation of genetic diversity in Chinese indigenous chicken breeds using microsatellite markers显示文摘China is rich in chicken genetic resources, and many indigenous breeds can be found throughout the country. Due to poor productive ability, some of them are threatened by the commercial varieties from domestic and foreign breeding companies. In a large-scale investigation into the current status of Chinese poultry genetic resources, 78 indigenous chicken breeds were surveyed and their blood samples collected. The genomes of these chickens were screened using microsatellite analysis. A total of 2740 individuals were genotyped for 27 microsatellite markers on 13 chromosomes. The number of alleles of the 27 markers ranged from 6 to 51 per locus with a mean of 18.74. Heterozy-gosity (H) values of the 78 chicken breeds were all more than 0.5. The average H value (0.622) and polymorphism information content (PIC, 0.573) of these breeds suggested that the Chinese indige-nous chickens possessed more genetic diversity than that reported in many other countries. The fixa-tion coefficients of subpopulations within the total population (FST) for the 27 loci varied from 0.065 (LEI0166) to 0.209 (MCW0078), with a mean of 0.106. For all detected microsatellite loci, only one (LEI0194) deviated from Hardy-Weinberg equilibrium (HWE) across all the populations. As genetic drift or non-random mating can occur in small populations, breeds kept on conservation farms such as Langshan chicken generally had lower H values, while those kept on large populations within con-servation regions possessed higher polymorphisms. The high genetic diversity in Chinese indigenous breeds is in agreement with great phenotypic variation of these breeds. Using Nei’s genetic distance and the Neighbor-Joining method, the indigenous Chinese chickens were classified into six categories that were generally consistent with their geographic distributions. The molecular information of genetic diversity will play an important role in conservation, supervision, and utilization of the chicken re-sources.QU Lujiang1, LI Xianyao1, XU Guifang2, CHEN Kuanwei3, YANG Hongjie2, ZHANG Longchao1, WU Guiqin1, HOU Zhuocheng1, XU Guiyun1 & YANG Ning1 1. College of Animal Science and Technology, China Agricultural University, Beijing 100094, China 2. National Service for Animal Husbandry and Veterinarian, Beijing 100026, China 3. Institute of Poultry Science, Chinese Academy of Agricultural Science, Yangzhou, Jiangsu 200331, China 2006Science China(Life Sciences)2006,49,4:9
16Effect of rock mass structure and block size on the slope stability——Physical modeling and discrete element simulation显示文摘This paper studies the stability of jointed rock slopes by using our improved three-dimensional discrete element methods (DEM) and physical modeling. Results show that the DEM can simulate all failure modes of rock slopes with different joint configurations. The stress in each rock block is not homogeneous and blocks rotate in failure development. Failure modes depend on the configuration of joints. Toppling failure is observed for the slope with straight joints and sliding failure is observed for the slope with staged joints. The DEM results are also compared with those of limit equilibrium method (LEM). Without considering the joints in rock masses, the LEM predicts much higher factor of safety than physical modeling and DEM. The failure mode and factor of safety predicted by the DEM are in good agreement with laboratory tests for any jointed rock slope.LI Shihai1, LIAN Zhenzhong1,2 & J. G. Wang3 1. Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, China 2. Graduate School, Chinese Academy of Sciences, Beijing 100060, China 3. Tropical Marine Science Institute, National University of Singapore, Singapore 119260 2005Science China(Technological Sciences)2005,48,z1:8
17A new family of windows——convolution windows and their applications显示文摘A new family of windows is constructed by convolutions via a few rectangular windows with same time width and is thus referred to as convolution windows. The expressions of the second-order up to the eighth-order convolution windows in both the time and frequency domains are derived. Their applications in high accuracy harmonic analysis of periodic signals are investigated. Comparisons between the proposed windows and some known windows with the same width shows that, when the synchronous deviation of data sampling is slight, the proposed ones have the least effect of spectral leakage. Therefore, the new windows are well suited for high accuracy harmonic analysis and parameter estimation for periodic signals. The error analysis and computer simulations show that the estimation errors, corresponding to frequency, amplitude and phase of every harmonic component of a signal, are proportional to the pth power of the relative frequency deviation in case of the pth-order convolution window is applied to windowing signal of approximately p cycles. By introducing real time adjustment in sampling interval, the proposed algorithm can adaptively trace signal frequency and lead to less sampling synchronous deviation. The proposed approach has the advantages of easy implementation and high measure precision and can be used in harmonic analysis of quasi-periodic signals whose fundamental frequency drifts slowly with time.ZHANG Jieqiu1,2, LIANG Changhong1 & CHEN Yanpu3 1. Department of Applied Math. & Phys., College of Science, Airforce Engineering University, Xi’an 710051, China 2. National Key Laboratory of Antennas and Microwave Technology, Xidian University, Xi’an 710071, China 3. Computer Center, Xi’an Communication College, Xi’an 710106, China 2005Science China(Technological Sciences)2005,48,4:7
18Influence of valence electron structures of phase and biphase interfaces of sulfides on hot brittleness in steel显示文摘This paper calculates the electron structures of phase of FeS, MnS and their biphase interface electron structures with austenite in steel. The precipitation and the transformation of FeS and MnS are investigated through studying the valence electron pair numbers on the strongest bond nA with the structure formation factor S. The continuity of electron density and its relation with stress are explored in the biphase interfaces with the electron density difference D. Using nA, S, D? we explain the reason why FeS can bring about hot brittleness in steel and the physical mechanism why MnS may eliminate or inhibit hot brittleness, based on which satisfying results are obtained by calculating several rare-earth sulfides.LIU Yan1,3, LIU Zhilin1, ZHANG Chengwei1,2 & ZHOU Yingchun1 1. Liaoning Institute of Technology, Jinzhou 121001, China 2. China National Oil and Gas Exploration and Development Corporation, Beijing 100011, China 3. College of Science, Northeastern University, Shengyang 110006, China 2004Science China(Technological Sciences)2004,47,4:7
19Population information extraction in Chaohu watershed based on RS and GIS显示文摘It is always difficult to extract population in-formation of small watershed during the region environment assessment. The report adopted compound areal interpola-tion to study the population in Chaohu watershed with the GIS technique and landuse interpretation data from remote sensing. The result indicated that the method is effective to extract population information of small watershed.LIU Jianjun1,2 & LI Chunlai3 1. Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China 2. Graduate School, Chinese Academy of Sciences, Beijing 100039, China 3. National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China Correspondence should be addressed to Liu Jianjun (e-mail: dhsliujj@ hotmail.com) 2003Chinese Science Bulletin2003,48,2:6
20Alterations in DNA methylation and genome structure in two rice mutant lines induced by high pressure显示文摘By using high-pressure treatment, two mutant lines were obtained from a genetically stable japonica rice cultivar Bijing38. Genomic DNA of the mutant lines, together with the original line (Bijing38), was either undigested or digested by Hpa II/Msp I, and then subjected to molecular analy-sis using two markers, ISSR and RAPD. Results indicated that changes in the PCR amplification pro-files of both markers are apparent in the two mutant lines compared with the original rice cultivar, suggesting that there had been both sequence changes and DNA methylation modifications in the mutant lines. Southern blot analysis using diverse sequences, including two cellular genes (S2 and S3), a set of retrotransposons (Osr7, Osr36, Tos19 and more), and a MITE transposon family (mPing and Pong), confirmed the results, and indicated that changes in DNA methylation pattern, genomic structure, and possible activation of some transposons indeed occurred in the mutant lines. Moreover, these changes are stably maintained through selfed generations and in different organs. Thus, our results indicate that it is possible to obtain stable mutants in rice by high pressure treatments, and the molecular basis of the mutants may include both genetic and epigenetic changes. Therefore, high hydrostatic pressure seems a promising approach for plant mutagenesis.SHEN Sile1,3, WANG Zhenwei3, SHAN Xiaohui2, WANG Hua3, LI Ling3, LIN Xuyun2, LONG Likun2, WENG Kenan4, LIU Bao2 & ZOU Guangtian1 1. National Laboratory of Superhard Materials, Jilin University, Changchun 130012, China 2. Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024, China 3. College of Life Science, Jilin University, Changchun 130012, China 4. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 2006Science China(Life Sciences)2006,49,2:6
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