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A possible Younger Dryas-type event during Asian monsoonal Termination 3

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Science China Earth Sciences 2006年第9期49卷 982-990页

作者： CHEN Shitao1, WANG Yongjin1, KONG Xinggong1, LIU Dianbing1, CHENG Hai2 & R.L. Edwards2 1. College of Geography Science, Nanjing Normal university, Jiangsu Key Laboratory of Environmental Change and Ecological Construction, Nanjing 210097, China 2. department of Geology and geophysics, {3., Minneapolis {4., usa College of Geography Science Nanjing Normal University Jiangsu Key Laboratory of Environmental Change and Ecological Construction Nanjing China department of Geology and geophysics University of Minnesota Minneapolis USA

Seven U-Th dates, 560 δ 18O data and microscopic sequences were measured for sta- lagmites from two high-altitude caves in Shennongjia area, Hubei Province. Variations of the de- cadal-resolution stalagmite δ 18O record from Swan Cave (1600 m elevation) reflect large spatial changes in circulation strength and precipitation of Asian monsoon. The evidence comes from a great similarity among the stalagmite δ 18O records from Nanjing, Jiangsu Province; Libo, Guizhou Province and here studied area during the last deglaciation, including a part interval of Younger-Dryas event and Bolling-Allerod. A 3.-year-resolution stalagmite δ 18O record from Yongxing Cave (14.0 m eleva- tion), 70 km away from Swan Cave, reveals a rapid transition of Asian monsoon climate during Ter- mination 3.at about 24.±5 kaBP. Based on 3.U-Th dates and about 5000 continuous annual bands, a millennial dry episode has been observed during Asian monsoonal Termination 3.from the Yongxing δ 18O profile. With respect to its structure, duration and transition, the dry reversal, as indicated by our stalagmite δ 18O record, generally agrees with the pattern of the YD event well-expressed in the Chi- nese stalagmite δ 18O records. This YD-type event is characterized by a large decrease in δ 18O value as much as 2.3.‰, more than half of the δ 18O excursion between glacial/interglacial periods, and lasts 13.1±59 a determined by the annual counting chronology. After this event, the monsoon climate shifted abruptly into the interglacial period within 74.4.a. Our data corroborate the view that the re- peated occurrence of YD-type event was not an “accident”, possibly resulted from the coupling of ice-sheet and oceanic/atmospheric circulations.

关键词： stalagmite, Termination 3. Asian monsoon, YD-type event, Shennongjia, Hubei Province.

Distributions of fatty acids in a stalagmite related to paleoclimate change at Qingjiang in Hubei,southern China

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Science China Earth Sciences 2005年第9期48卷 1463-1469页

作者： XIE Shucheng1,HUANG Junhua1,WANG Hongmei2,YI Yi1,HU Chaoyong1, CAI Yanjun3.& CHENG Hai4.1. Faculty of Earth Science,China university of Geosciences,Wuhan 4.0074.China 2. School of Environmental Studies,China university of Geosciences,Wuhan 4.0074.China 3. SKLLQG,Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,China 4. department of Geology and geophysics,{4.,mn55455,usa Faculty of Earth Science China University of Geosciences Wuhan China School of Environmental Studies China University of Geosciences Wuhan China SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an China department of Geology and geophysics University of Minnesota USA

Fatty acids extracted from a subtropical stalagmite at Qingjiang in Southern China’s Hubei Province were analysed using gas chromatography-mass spectrometry. These n-alkanoic acids range from C14.to C26 in carbon number, maximizing at C16, with a second dominance at C22. In contrast to the stalagmite analysed, the overlying soils are characterized by the dominance of heavy-molecular-weight homologues (>C20). The n-fatty acids in the stalagmite were proposed to be contributed by both the soil ecosystems and the microbes harboring in the percolating water and the cave. The ratios of unsaturated to saturated n-fatty acids (C16:1i/C16:0, C18:1/C18:0) appear to show trends comparable with the oxygen isotope records of the stalagmite carbonate, with enhanced values associated with the cold episode such as Heinrich event 1. This paleoclimate-dependent record of the n-fatty acids might reflect microbial changes in physiology and activity in response to the temperature. This record shows somewhat difference from the previous paleoclimate signal extracted from n-alkanols and n-alkan-2-ones of the same stalagmite. The acid record fails to document the well-known Younger Dryas event which was effectively shown by the latter two biomarkers derived from soil ecosystems. This discrepancy might result from the changing biogeochemical impact on different lipid fractions as well as the varied organism populations in different ecosystems.

关键词： biomarker, ecosystem, microbe, speleothem, paleoclimate, Quaternary.

Integration of light signaling with photoperiodic flowering and circadian rhythm

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Cell Research 2005年第8期15卷 559-566页

作者： Min NI* department of Plant Biology, university of minnesota, St. Paul, mn 55108, usa department of Plant Biology University of Minnesota St. Paul USA

Plants become photosynthetic through de-etiolation, a developmental process regulated by red/far-red light-absorbing phytochromes and blue/ultraviolet A light-absorbing cryptochromes. Genetic screens have identified in the last decade many far-red light signaling mutants and several red and blue light signaling mutants, suggesting the existence of distinct red, far-red, or blue light signaling pathways downstream of phytochromes and cryptochromes. However, genetic screens have also identified mutants with defective de-etiolation responses under multiple wavelengths. Thus, the opti- mal de-etiolation responses of a plant depend on coordination among the different light signaling pathways. This review intends to discuss several recently identified signaling components that have a potential role to integrate red, far-red, and blue light signalings. This review also highlights the recent discoveries on proteolytic degradation in the desensitization of light signal transmission, and the tight connection of light signaling with photoperiodic flowering and circadian rhythm. Studies on the controlling mechanisms of de-etiolation, photoperiodic flowering, and circadian rhythm have been the fascinating topics in Arabidopsis research. The knowledge obtained from Arabidopsis can be readily applied to food crops and ornamental species, and can be contributed to our general understanding of signal perception and transduction in all organisms.

关键词： circadian regulation cryptochromes photomorphogenesis photoperiodic flowering phytochromes.

Analysis and application of automatic deformation monitoring data for buildings and structures of mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 516-522页

作者： XIAO Jie1, 2, 3. ZHANG Jin4.1. Institute of Geodesy and geophysics, Chinese Academy of Sciences, Wuhan 4.0077, China 2. Key Laboratory of Dynamic Geodesy, Institute of Geodesy and geophysics, Chinese Academy of Sciences, Wuhan 4.0077, China 3. Graduate School of Chinese Academy of Sciences, Beijing 10004., China 4. department of Surveying and Mapping, Taiyuan university of Technology, Taiyuan 03.024. China Institute of Geodesy and geophysics Chinese Academy of Sciences Wuhan 430077 China Key Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Graduate School of Chinese Academy of Sciences Beijing 100049 China department of Surveying and Mapping Taiyuan University of Technology Taiyuan 030024 China

The buildings and structures of mines were monitored automatically using modern surveying technology. Through the analysis of the monitoring data, the deformation characteristics were found out from three aspects containing points, lines and regions, which play an important role in understanding the stable state of buildings and structures. The stability and deformation of monitoring points were analysed, and time-series data of monitoring points were denoised with wavelet analysis and Kalman filtering, and exponent function and periodic function were used to get the ideal deformation trend model of monitoring points. Through calculating the monitoring data obtained, analyzing the deformation trend, and cognizing the deformation regularity, it can better service mine safety production and decision-making.

关键词： wavelet analysis Kalman filtering deformation monitoring data analysis mine

The *** climate abrupt events in the early and middle Holocene:Stalagmite oxygen isotope record from Maolan,Guizhou,China

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Science China Earth Sciences 2005年第4期48卷 530-537页

作者： 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 54.004. China 2. Geology and geophysics {3., minnesota university, {4., usa 3. The Management of Maolan National Nature Reserve, Libo 5584.0, China The Karst Dynamic Laboratory IKG CAGS Guilin China Geology and geophysics department Minnesota University MN USA The Management of Maolan National Nature Reserve Libo China

The isotope records which range from 3.9 kaBP to 15.7 kaBP with an average resolution of 90 a have been obtained from 4. 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 *** 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.

关键词： isotope record, climate event, stalagmite, Libo, Guizhou.

LOD score exclusion analyses for candidate disease susceptibility genes using case-parents design

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Progress in Natural Science:Materials International 2006年第1期16卷 30-38页

作者： DENG Hongwen1,2,3.and GAO Guimin2,4.(1.Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Hunan Normal university, Changsha 4.0081, China 2.Osteoporosis Research Center, Creighton university Medical Center, Omaha NE 6813., usa 3. department of Biomedical Sciences, Creighton university, Omaha NE 6813., usa 4. Virginia Bioin format ics Institute and department of Statistics, Virginia Polytechnic Institute and State university, Blacksburg VA 24.61-03.5, usa) Laboratory of Molecular and Statistical Genetics College of Life Sciences Hunan Normal University Changsha 410081 China Osteoporosis Research Center Creighton University Medical Center Omaha NE 68131 United States department of Biomedical Sciences Creighton University Omaha NE 68131 United States Virginia Bioinformatics Institute and department of Statistics Virginia Polytechnic Institute and State University Blacksburg VA 24061-0315 United States

The focus of almost all the association studies of candidate genes is to test for their importance. We recently developed a LOD score approach that can be used to test against the importance of candidate genes for complex diseases and quantitative traits in random samples. As a complementary method to regular association analyses, our LOD score approach is powerful but still affected by the population admixture, though it is more conservative. To control the confounding effect of population heterogeneity, we develop here a LOD score exclusion analysis using case-parents design, the basic design of the transmission disequilibrium test (TDT) approach that is immune to population admixture. In the analysis, specific genetic effects and inheritance models at candidate genes can be analyzed and if a LOD score is ≤ - 2. 0, the locus can be excluded from having an effect larger than that specified. Simulations show that this approach has reasonable power to exclude a candidate gene having small genetic effects if it is not a disease susceptibility locus (DSL) with sample size often employed in TDT studies. Similar to association analyses with the TDT in nuclear families, our exclusion analyses are generally not affected by population admixture. The exclusion analyses may be implemented to rule out candidate genes with no or minor genetic effects as supplemental analyses for the TDT. The utility of the approach is illustrated with an application to test the importance of vitamin D receptor (VDR) gene underlying the differential risk to osteoporosis.

关键词： association studies candidate genes case-parents design disease susceptibility locus exclusion mapping LOD score.

High resolution stalagmite δ18O records over the past 1000 years from Dongge Cave in Guizhou

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Science Bulletin 2005年第10期50卷 1003-1008页

作者： HE Yaoqi1, WANG Yongjin1, KONG Xinggong1 & CHENG Hai2 1. College of Geography Science, Nanjing Normal university, Nanjing 210097, China 2. department of Geology and geophysics, {3. university, Mineapolis mn 55455, usa College of Geography Science Nanjing Normal University Nanjing China department of Geology and geophysics Minnesota University Mineapolis USA

Based on MC-ICP-MS U-series dating and stable O-isotope analysis results, a 4.5 years resolution monsoon record over the past 1000 years has been estab- lished for two stalagmites from Dongge Cave, Guizhou. The high resolution oxygen isotope record serves as a proxy for variations in rainfall of Asian southwest monsoon over the Yunnan-Guizhou Plateau. A close relation of the δ 18O record with the ?14. record from tree rings largely reflects impact of centennial-scale solar activity on the monsoon climate changes. The conspicuous decrease in the δ 18O value at AD 1720 indicates an abrupt increase in monsoon rainfall, sug- gesting that an atmospheric-oceanic couple over the tropical Indian Ocean plays an important role in rapid increase of the Northern Hemisphere temperature over the last century.

关键词： cave stalagmite oxygen isotope southwest monsoon solar activity Guizhou.

Effects of sleep deprivation on gamma oscillation of waking human EEG

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Progress in Natural Science:Materials International 2008年第12期18卷 1533-1537页

作者： Ning Li~a Yan Wang~a Mingshi Wang~a Haiying Liu~(a,b) a College of Precision Instrument and Opto-Electronics Engineering,Tianjin university,Tianjin 3.0072,China b department of Radiology university of minnesota,Minneapolis,mn {3.,{4. College of Precision Instrument and Opto-Electronics Engineering Tianjin University Tianjin 300072 China department of Radiology University of Minnesota Minneapolis MN 55455 USA

This study compares and evaluates the effect of sleep deprivation (SD) on human brain cognition by analyzing the recorded EEG data under normal and 24.h sleep deprived *** auditory event-related potentials were collected from 14.healthy volunteers,and the statistical values of wavelet-transformed EEG in gamma band were decomposed by parallel factor analysis (PARAFAC) to identify where the differences appeared in the time,frequency and spatial *** results showed that the changes of brain states caused by SD appeared around 4. Hz at about 4.0 ms after stimulation on prefrontal and frontal *** effects of SD on neuronal activity and oscillation were *** analysis of the EEG data by the wavelet transform and PARAFAC can be an integrated way to estimate the change of brain states in the three domains.

关键词： Gamma oscillation Sleep deprivation Event-related potential Wavelet transform Parallel factor Neuronal activity

Identification of two distinct transactivation domains in the pluripotency sustaining factor nanog

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Cell Research 2003年第6期13卷 499-502页

作者： GUANG Jin PAN, DUAN QING PEI Institute of Pharmacology, department of Biological Sciences and Biotechnology and State Key Labora tory of Biomembrane and Membrane Biotechnology, Tsinghua Institutes of Biomedicine, Tsinghua university, 100084.Beijing, China. E-mail: duanqing@aol.comdepartment of Pharmacology, university of minnesota, Minneapolis, {4., usa department of Biological Sciences and Biotechnology and State Key Laboratory of Biomembrane and Membrane Biotechnology Institute of Pharmacology Tsinghua Institutes of Biomedicine Tsinghua University Beijing China department of Pharmacology University of Minnesota Minneapolis USA

Nanog is a newly identified homeodomain gene that functions to sustain the pluripotency of embryonic stem cells. However, the molecular mechanism through which nanog regulates stem cell pluripotency remains unknown. Mouse nanog encodes a polypeptide of 3.5 residues with a divergent homeodomain similar to those in the NK-2 family. The rest of nanog contains no apparent homology to any known proteins characterized so far. It is hypothesized that nanog encodes a transcription factor that regulates stem cell pluripotency by switching on or off target genes. To test this hypothesis, we constructed fusion proteins between nanog and DNA binding domains of the yeast transcription factor Gal4.and tested the transactivation potentials of these constructs. Our data demonstrate that both regions N- and C- terminal to the homeodomain have transcription activities. Despite the fact that it contains no apparent transactivation motifs, the C-terminal domain is about 7 times as active as the N-terminal one. This unique

关键词： nanog pluripotency stem cells self renewal transactivation domain homeoprotein homeodomain