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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 departmentofPlantBiology UniversityofMinnesotaSt.PaulMN55108USA

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.

Archean relic body at lower crust in Sulu area:Evidence from magnetic data

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Chinese Science Bulletin 2003年第6期48卷 589-593页

作者： WU Qifan1,2, LU Fengxiang3. LIU Qingsheng3. ZHENG Jianping3. WANG Maoji2 & WU Wenli4.1. department of Engineering Physics, Tsinghua university, Beijing 100084. China 2. Aero Geophysical Survey & Remote Sensing Center, Beijing 100083. China 3. China university of Geosciences, Wuhan 4.0074. China 4. Institute of Geophysical & Geochemical Exploration, Langfang 065000, China Aero Geophysical Survey & Remote Sensing Center Beijing 100083 China China university of Geosciences Wuhan 430074 China Institute of Geophysical & Geochemical Exploration Langfang 065000 China department of Engineering Physics Tsinghua University Beijing 100084 China

After the new 1︰1000000 aero magnetic data were processed and the three-dimensional inversion work was carried out, a vast high magnetic body northwestward was discovered. The magnetic body is located at the depth of about 20 km on the west side of Tanlu fault and at about 25 km on the east side of Tanlu fault beneath the Sulu area. There is a difference of vertical distance of 3.5 km in depth between both sides. We think that the magnetic body is an Archean metamorphic plate and belongs to the North China block. The discovery of the magnetic body is significant for us to reconstruct the structure model of the Sulu orogenic belt, delineate the suture of collision between the North China block and the Yangtze block, and estimate the depth of slipping surface when the eastside of Tanlu fault moved northward.

关键词：苏鲁地区地壳下层太古代残余体地球物理调查区域性磁场三维反演苏鲁造山带郯鲁断裂带大别-苏鲁超高压变质带

Effects of astragaloside IV on pathogenesis of metabolic syndrome in vitro

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Acta Pharmacologica Sinica 2006年第2期27卷 229-236页

作者： Ming-en XU~(2,3.4. Shang-zhi XIAO~3.Yong-hong SUN~3.Yang OU-YANG~3.Xiao-xiang ZHENG~(3.4. ~2department of Biomedical Engineering,Hangzhou Dianzi {3..Hangzhou 3.0018 ~3.2} of Biomedical Engineering.Zhejiang {3..Hangzhou 3.0027.China department of Biomedical Engineering Hangzhou Dianzi UniversityHangzhou 310018 China. xumingen@***

Aim:To investigate the diverse pharmacological actions of astragaloside IV fromthe perspective of metabolic syndrome,and to investigate the effect of the drugon the pathogenesis of metabolic ***:Adipogenesis was usedas an indicator of the effect of astragaloside Ⅳ on preadipocyte differentiation,and was measured by using an oil red O *** uptake was determined bymeasuring the transport of [2-3.]-deoxyglucose into the *** concentrationsof peroxisome proliferator-activated receptor-γ（PPARγ）and aP2 mRNA were de-termined by using reverse transcription-polymerase chain *** viability loss of endothelial cells were detected by using flow cytometry andthe WST-1 assay,*** free Ca2+was labeled with Fluo-3.AMand measured by using a laser scanning confocal ***:Astragaloside Ⅳ can significantly potentiate insulin-induced preadipocyte differ-entiation at concentrations of 3.10,and 3. μg/mL,improve high glucose-inducedinsulin resistance in adipocytes at a concentration of 3. μg/mL,and prevent tumornecrosis factor（TNF）-α-induced apoptosis and viability loss at concentrations of10 and 3. μg/mL,and 3. μg/mL,respectively,in endothelial ***,wefound that these effects were partly due to the promotion of PPARγ expressionand to the inhibition of abnormal TNF-α-induced intracellular free Ca2+accumula-tion in endothelial ***:The diverse pharmacological actions ofastragaloside 1V can all be linked to metabolic syndrome *** studyprovides a new insight into the mechanism by which astragaloside Ⅳ exerts itseffect.

关键词： astragaloside Ⅳ metabolic syndrome X insulin resistance peroxisome proliferatoractivated receptors apoptosis calcium

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 1. The Karst Dynamic Laboratory 541004 IKG CAGS Guilin China 2. Geology and geophysics department Minnesota University 55455 MN USA 3. The Management of Maolan National Nature Reserve 558400 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.

Assessment of the modulated gradient model in decaying isotropic turbulence

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Theoretical & Applied Mechanics Letters 2011年第4期1卷 23-27页

作者： Hao Lu a) Saint Anthony Falls Laboratory,department of Civil Engineering,university of minnesota-Twin Cities,2 3.d Ave.SE,Minneapolis,mn 554.4.usa Saint Anthony Falls Laboratory Department of Civil Engineering University of Minnesota-Twin Cities 23rd Ave. SE Minneapolis MN 55414 USA

A recently introduced nonlinear model undergoes evaluations based on two isotropic turbulent cases:a university of Wiscosion-Madison case at a moderate Reynolds number and a Johns Hopkins university case at a high Reynolds *** model uses an estimation of the subgrid-scale(SGS) kinetic energy to model the magnitude of the SGS stress tensor,and uses the normalized velocity gradient tensor to model the structure of the SGS stress *** is performed for the first case through a comparison between direct numerical simulation(DNS) results and large eddy simulation(LES) results regarding resolved kinetic energy and energy *** the second case,we examine the resolved kinetic energy,the energy spectrum,as well as other key statistics including the probability density functions of velocities and velocity gradients,the skewness factors,and the flatness *** using the model are numerically stable,and results are satisfactorily compared with DNS results and consistent with statistical theories of turbulence.

关键词： large-eddy simulation subgrid-scale model isotropic turbulence

Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan university Journal of Natural Sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2, 3.,HUANG Zhiqin 2, 3. 4.1. The Faculty of Geography and Resources Science, Sichuan Normal university, Chengdu 610066, Sichuan, China 2. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 61004., Sichuan, China 3. Graduate university of the Chinese Academy of Sciences, Beijing 10004., China 4. Information Center of Land and Resources department of Sichuan Province, Chengdu 61004., Sichuan, China The Faculty of Geography Resources Science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate university of the Chinese Academy of Sciences 100049 Beijing China Information Center of Land Resources department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992 is extracted from the dynamic polygons of 2002. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 3.°. The areas of steep land cultivated had been slowly reduced from 1992 to 2002. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

Holocene grassland vegetation, climate and human impact in central eastern Inner Mongolia

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Science China Earth Sciences 2005年第7期48卷 1025-1039页

作者： HUANG Fei1, Kealhofer Lisa2, XIONG Shangfa3.& HUANG Fengbao1 1. Nanjing Institute of Geology and Paleontology,Chinese Academy of Sciences,Nanjing 210008,China 2. Anthropology and Sociology department,Santa Clara university,CA 95053.usa 3. Institute of Geology and {3.,Chinese Academy of Sciences,Beijing 100029,China Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Anthropology and Sociology department Santa Clara University CA 95053 United States Institute of Geology and Geoohysics Chinese Academy of Sciences Beijina 100029 China

Phytolith and pollen preserved in the Taipusi Banner paleosol profile, central eastern Inner Mongolia, provide evidence of Holocene grassland vegetation, climate and human impact. The combined phytolith and pollen records reveal a major change in vegetation composition about 5000 a BP. Before 5000 a BP, the vegetation was dominated by Aneurolepidium Chinese-Stipa grandis grassland of C4.grasses. After 5000 a BP, C4.grasses rapidly retreated, indicating a shift to colder and more arid conditions. The gradual invasion of Stipa krylovii, Ag-ropyron desertorum, Ephedra, Chenopodiaceae and Caragana reveal the onset of grassland degeneration. Between 10000 and 8720 a BP, the Aneurolepidium Chinese-Stipa grandis grassland included a small proportion of Artemisia shrub and Echionopos type plants, implying a strong winter monsoon and very weak summer monsoon. From 8720 to 7000 a BP, C4.grasses were common, indicating a strengthening of the summer monsoon. Between 7000 and 5000 a BP, the Holocene thermal maximum was evident, with a significant expansion of C4.grasses and the presence of some trees (such as Pinus and Betula, and so on) in or near the study site. From 4.00?000 a BP, a sandy grassland of Artemisia and Agropyron desertorum together with Aster-type taxa occurred. Precipitation amelioration took place between 3.00 and 2170 a BP, with a rapid development of Echinops type plants and a small expansion of C4.grasses. From 2170 a BP to present, human activities accelerated the process of grassland degeneration.

关键词： phytolith and pollen records grassland environment change human impact Holocene central eastern Inner Mongolia.

Test of magnetic susceptibility and grain-size age models of loess

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Progress in Natural Science:Materials International 2007年第11期17卷 1312-1317页

作者： Chen Yimeng1,2,3. Feng Zhaodong4.and Gong Huili1,2(1. MOE and Key Laboratory of Resources Environment and GIS of Beijing, Beijing 10003., China 2. Key Laboratory of 3. information Acquisition and Application, The Capital Normal university, Beijing 10003., China 3. department of Economics & Management of Huizhou university, Huizhou 516007, China 4. Key Laboratory of Western China’s Environmental Systems, Ministry of Education, Lanzhou university, Lanzhou 73.000, China) MOE and Key Laboratory of Resources Environment and GIS of Beijing Beijing 100037 China Key Laboratory of 3. information Acquisition and Application The Capital Normal University Beijing 100037 China department of Economics & Management of Huizhou university Huizhou 516007 China Key Laboratory of Western China’s Environmental Systems Ministry of Education Lanzhou University Lanzhou 730000 China

Ages of the stratigraphic boundary MIS1/2 and MIS3.4.of the Yuanbu loess section in Linxia are used as the basis of the nodal control age. The age of MIS1/2 and MIS3.4.are obtained from the latest international research result—the climatic events recorded in the stalagmite in the Hulu Cave in Nanjing, that MIS1/2 is 11.5 kaB.P. and MIS3.4.is 59.8 kaB.P.. The ages of the two climatic events contain three nodal age control models (Model 1: 0 kaB.P.—59.8 kaB.P.; Model 2: 0 kaB.P.—11.5 kaB.P. and 11.5 kaB.P.—59.8 kaB.P.; Model 3. 11.5 kaB.P.—59.8 kaB.P.), which are used as the nodal control age separately. The deposition times of various stratigraphic horizons are calculated by using the magnetic susceptibility age model and grain-size age model, and then compared with each other. In addition, the AMS14. age, OSL age and the ages of YD and H events are compared with the ages of the corresponding horizons calculated by the three models of nodal control ages. From the analyses of lithologic characters and climatic stages it has been found that both the magnetic susceptibility age model and the grain-size age model have some defects. Because the accurate control ages are selected as the nodal points of the glacial period or interglacial period, the stratigraphic deposition times determined by the high resolution of magnetic susceptibility age model and grain-size age model approximate to the actual ages. As for the relative accuracy of the two age models, the magnetic susceptibility age model is more accurate than the grain-size age model.

关键词： loess nodal control age magnetic susceptibility age model grain-size age model test

fMRI time series analysis based on stationary wavelet and spectrum analysis

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Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2,3., ZHAO Xia~4. SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 10004., China 2. Graduate School of Chinese Academy of Sciences, Beijing 10004., China 3. {3. of Physics, Zhoukou Normal university, Zhoukou 4.6100, China 4. Research Imaging Center, university of Texas Health Science Center, San Antonio, Texas 78229, usa 5. National ASIC Design and Engineering Center, Institute of Automation, Chinese Academy of Sciences, Beijing 10004., China 6. {3. of Physics, Zhejiang university, Hangzhou 3.0027, China) [a]Key Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China [b]Graduate School of Chinese Academy of Sciences Beijing China [c]department of Physics Zhoukou Normal University Zhoukou China [d]Research Imaging Center University of Texas Health Science Center San Antonio Texas USA [e]National ASIC Design and Engineering Center Institute of Automation Chinese Academy of Sciences Beijing China [f]department of Physics Zhejiang University Hangzhou China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.