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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 {3., university of minnesota, minneapolis mn55455, 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 (1400 m eleva- tion), 70 km away from Swan Cave, reveals a rapid transition of Asian monsoon climate during Ter- mination 3.at about 245±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.

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,{3.,mn 55455,usa 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 40 Hz at about 400 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

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 {3., minnesota university, Mineapolis mn 55455, usa College of Geography Science Nanjing Normal University Nanjing 210097 China

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 ?14C 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.

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 43.074,China 2. School of Environmental Studies,China university of Geosciences,Wuhan 43.074,China 3. SKLLQG,Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,China 4. department of {3. and geophysics,university of minnesota,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.

Rheology of Partially Molten Olivine Aggregates under Water-Saturated Conditions

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Continental Dynamics 1997年第1期 54-62页

作者： BAI Wuming (Institute of geophysics, Chinese Academy of Sciences, Beijing 100101, China) MEI Shenghua David KOHLSTEDT (department of geology and geophysics, university of minnesota, mn 55455, usa)

The influence of basaltic melt and water content on the high-temperature plastic deformation behavior of olivine aggregates was studied by performing a series of high-temperature creep experiments. The specimens, which are the powder of San Carols olivine plus 1, 4, or 7 wt% MORB, with the grain size of 10-20 μm, were hotpressed. Deformation experiments were conducted in a gas-medium apparatus at a confining pressure of 3.0 MPa and temperature of 13.3.K to 1473.K. Water was supplied by dehydration of TALC near 1073.K. The hy- droxyl concentration in the samples was determined from Fourier-Transform Infrared (FTIR) spectra.

关键词： partial melting water-saturated conditions rheology high pressure and high temperature

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 541004, China 2. geology and geophysics department, {3. university, mn55455, usa 3. The Management of Maolan National Nature Reserve, Libo 558400, 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 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 *** 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.

Cell transplantation and cardiac recovery:myocardial regeneration from endogenous cardiac progenitor cells

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岭南心血管病杂志 2011年第S1期17卷 34-35页

作者： Jianyi Zhang (department of Medicine,university of minnesota Medical School,university of minnesota Medical School,minneapolis,mn 55455,usa)

Following the bone marrow or cardiac derived progenitor cells transplantation,improved left ventricular(LV) function,decreased LV remodeling, and decreased fibrosis of non-infarcted LV regions,and in some cases,the reduction of infarct scar size have been reported to occur in animal mycardial infarction(MI) *** clinical trials, stem cell transplantation has also been associated with significant,but modest improvements of LV functional *** beneficial effects do occur although in many animal studies there is often very low long term engraftment or transdifferentiation of transplanted cells into myocytes and vascular ***,paracrine signals generated by the implanted progenitor cells seem to play an important role in limiting or reversing myocardial damage as- sociated with acute *** signaling effects include increased myocardial vascularization and reduced apoptosis of native cardiomyocytes;these responses are most prominent in peri-myocardial infarction (MI) boarder zone(BZ) of the *** much data supports the possibility that engrafted progenitor cells can mobilize endogenous cardiac progenitor cells(CPC) to the cardiac injury site and also stimulate them to propagate and transd-ifferentiate into cardiomyocytes and vascular cells, this concept remains *** and others have reported evidences supporting the view that endogenous CPC can be stimulated to differentiate and partially replace cardiomyocytes destroyed during an *** from our laboratory will be reviewed.

关键词： progenitor endogenous remodeling infarct regeneration differentiate mobilize possibility stimulate propagate

Leukolysin/MMP25/MT6-MMP: a novel matrix metalloproteinase specifically expressed in the leukocyte lineage

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Cell Research 1999年第4期9卷 291-303页

作者： PEI DUANQING(department of Pharmacology, 6-120 Jackson Hall, 3.1Church St. S.E., university of minnesota, minneapolis,mn {3., usa)Tel: 612-626-1468 Fax: 612-625-8408 E-mail: peixx003.tc. umn. edu departmentofPharmacology UniversityofMinnesotaMinneapolis55455USA.peixx003@tc.umn.edu

INTRODUCTIONMembersofthematrixmetajloproteinases(MMP)havebeenconsistentlyimplicatedinthedestructionofextracellularmatrix(ECM)undermanypathophysiologicalconditionsfromangiogenesistoajrthritis[1-5].Evolvedfrommodulardom... 详细信息

关键词： MT6-IMP MMP25 leukolysin MAP Matrix Remodeling Leukocytes.

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,{3., minneapolis, mn55455, usa 1Institute of Pharmacology Department of Biological Sciences and Biotechnology and State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua Institutes of Biomedicine Tsinghua University 100084 Beijing China. E-mail: duanqing@*** 2department of Pharmacology University of Minnesota Minneapolis MN55455 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