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fMRI time series analysis based on stationary wavelet and spectrum analysis

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 {2. {4., Institute of High Energy Physics, chinese academy of sciences, beijing 10004., china 2. Graduate School of chinese academy of sciences, beijing 10004., china 3. Department of Physics, Zhoukou Normal University, Zhoukou 4.6100, china 4. Research Imaging Center, University of Texas Health Science Center, San Antonio, Texas 782.9, USA 5. National ASIC Design and Engineering Center, Institute of Automation, chinese academy of sciences, beijing 10004., china 6. Department of Physics, Zhejiang University, Hangzhou 31002., china) key laboratory of Nuclear {2. techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Graduate School of chinese academy of sciences Beijing 100049 China Department of Physics Zhoukou Normal University Zhoukou 466100 China Research Imaging Center University of Texas Health Science Center San Antonio TX 78229 United States National ASIC Design and Engineering Center Institute of Automation Chinese Academy of Sciences Beijing 100049 China Department of Physics Zhejiang University Hangzhou 310027 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.

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The gravitational gradient tensor’s invariants and the related boundary conditions

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Science china Earth sciences 2010年第5期53卷 781-790页

作者： YU JinHai1,2.3 & ZHAO DongMing4.1 College of Earth Science, Graduate University of chinese academy of sciences, beijing 10004.,{2. 2.Institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 4.0077,{2. 3 State key laboratory of Astronautic Dynamics, Xi’an 71004.,{2. 4.Zhengzhou Institute of Surveying and Mapping, Zhengzhou 4.0052.{2. College of Earth Science Graduate University of Chinese Academy of Sciences Beijing China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China State key laboratory of Astronautic Dynamics Xi’an China Zhengzhou Institute of Surveying and Mapping Zhengzhou China

Here we report new approaches of recovering the Earth gravitational field from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometric data with the help of the gradient tensor’s invariants. Our results only depend on GOCE satellite’s position and gradiometry, in other words, they are completely independent of the satellite attitude. First, starting from the invariants, linearization models are established, which can be referred as the general boundary conditions on the satellite’s orbit. Then, the spherical approximation expressions for the models are derived, and the corresponding solving methods for them are discussed. Furthermore, considering effects of J2.term, the spherical approximation models are improved so that the accuracies of the boundary conditions can be theoretically raised to O ( J 2.2.T), which is approximately equivalent to O(T2.. Finally, some arithmetic examples are constructed from EGM96 model based on the derived theories, and the computational results illustrate that the spherical models have accuracies of 10-7 and the order recovering the gravitational field can reach up to 2.0, and the models with regard to effect of J2.term have accuracies of 10-8 and the order can reach up to 2.0.

关键词： the Earth’s gravitational field gravitational gravidiometry tensor’s invariant

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Periodicity of Retzius lines in fossil Pongo from South china

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chinese Science Bulletin 2012年第7期57卷 790-794页

作者： HU Rong1,2.3, ZHAO LingXia1,2.& WU XinZhi2.1 key {4. of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology,{2., beijing 10004., china 2.{4. of Human Evolution, Institute of Vertebrate Paleontology and Paleoanthropology,{2., beijing 10004., china 3 Graduate University of{2., beijing 10004., china key laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China laboratory of Human Evolution Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

Periodicity of Retzius lines is a key factor in dental development. In this study, we examined the periodicity of Retzius lines in fossil Pongo from South china using polarized light microscope observation of dental ground sections. The periodicities all of the 15 teeth were 9 d. Comparisons of periodicity were made with extant primates, fossil apes and hominins. Periodicity of fossil Pongo from South china was relatively long but fell within the variation of extant Pongo, Gorilla and modern human, and longer than periodicity of Pan and other extant primates. Fossil Pongo from South china was similar to Lufengpithecus and Sivapithecus, shorter than Gigantopithecus and longer than European and African fossil apes and most early hominins in periodicity. Generally, the periodicities of Asian large-body fossil apes were longer than the periodicities of European and African large-body fossil apes in Miocene. Difference among species and trend of evolution in periodicity were analyzed and discussed. We found that periodicity might gradually increase from Proconsul in early Miocene to several fossil apes in Miocene and then Gigantopithecus in Pleistocene. In addition, this study made correlate {4. between periodicity and body mass respectively in males and females of six extant apes and five fossil apes, and found that periodicity positively correlated with body mass.

关键词：周期性变化中国南方大猩猩化石灵长类动物早中新世类人猿显微镜观察

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Evaluation of 10 plant barcodes in Bryophyta (Mosses)

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Journal of Systematics and Evolution 2010年第1期48卷 36-46页

作者： 1,2.Yan LIU 3 Hai-Fei YAN 4.Tong CAO 3 Xue-Jun GE 1(Institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, china) 2.Graduate University of the chinese academy of sciences, beijing 10004., china) 3(key laboratory of Plant Resources Conservation and Sustainable Utilization, South china Botanical Garden, chinese academy of sciences, Guangzhou 510650, china) 4.College of Life & Environment sciences, Shanghai Normal University, Shanghai 2.02.4. china) (Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China) (Graduate University of the chinese academy of sciences Beijing 100049 China) (key laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China) (College of Life & Environment sciences Shanghai Normal University Shanghai 200234 China)

DNA barcoding is a molecular tool that uses a standardized DNA region to identify *** preliminary study reported here is the first attempt to specifically focus on universality and attributes of candidate barcodes across a wide systematic range of *** tested eight previously proposed plant barcoding regions(atpF-atpH, ITS2. matK, psbK-psbI, rbcL, rpoB, rpoC1, and trnH-psbA) and two popular phylogenetic markers(rps4.and trnL-trnF of cpDNA) in 4. moss species and 9 liverwort species, representing half of the orders in moss *** ITS2. rbcL, rpoC1, rps4. trnH-psbA and trnL-trnF regions showed good universality, and therefore the efficacy of these loci as DNA barcodes was further evaluated in 36 mosses and 2.liverworts, each of which included two to three individuals per *** five loci, ***, rpoC1, rps4. trnH-psbA and trnL-trnF, were easy to amplify and sequence and showed significant inter-specific genetic variability, making them potentially useful DNA barcodes for *** best performing single loci were the rbcL and rpoC1 coding *** loci showed equivalent performance and combinations of them did not greatly increase their discrimination *** addition, phylogenies generated from each of the separate regions and multi-locus combinations by using best-fit and Kimura 2.parameter models were compared, but no significant difference was found.

关键词： Bryophyta DNA barcoding rbcL rpoC1 rps4 trnH-psbA trnL-trnF.

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Depside salts from Salvia miltiorrhiza improve myocardial microperfusion in rats using laser Doppler flowmetry

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Acta Pharmacologica Sinica 2007年第6期28卷 789-795页

作者： Xiao-fen LI~(2.3),Yi-ping WANG~(2.4.~2.State key {4..of Drug Research,Shanghai Institute of Materia Medica,Shanghai Institutes for Biological {2.,chinese academyof {2.,Shanghai 2.12.3,china,~3 Graduate School of chinese academy of sciences,beijing 10004.,china State key laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China Graduate School of chinese academy of sciences Beijing China

Aim:To investigate the effects of depside salts from Salvia miltiorrhiza on myo-cardial microperfusion and systemic hemodynamics in open-chest anaesthetizedSprague-Dawley ***:Myocardial microperfusion was measured bylaser Doppler flowmetry with a needle probe;cardiac output (CO) was determinedusing ultrasonic Doppler *** hemodynamic parameters,includingfemoral artery blood pressure,cardiac inotropy,and systemic vascular resistance(SVR) were simultaneously recorded by the PowerLab ***:Intrave-nous administration of S miltiorrhiza depside salts resulted in a significant imme-diate increase in CO and cardiac inotropy,but a fall in SVR.S miltiorrhiza depsidesalts (30 mg/kg and 60 mg/kg) promoted cardiac index (CI) by 12.2.±6.3% (P2..1%±3.5% (P2.9% (P4.0% (P<0.01) for 30 mg/kgand 60 mg/kg S miltiorrhiza depside salts,***:Theseresults indicated that S miltiorrhiza depside salts improved myocardial micro-perfusion,as well as CO.

关键词： lithospermate B myocardial microperfusion laser Doppler flowmetry cardiac output ultrasonic Doppler flowmetry

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Absolute radiometric calibration of CBERS-02.IRMSS thermal band

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Science china(Technological sciences) 2005年第S2期48卷 72-90页

作者： ZHANG Yong1,2.3, GU Xingfa1,3,4. YU Tao1,3, ZHANG Yuxiang5, CHEN Liangfu1,3, LI Xiaoying1,2.3, LI Xiaowen1,3 & HE Liming6 1. State key laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of{2. and beijing Normal University, beijing 100101, china 2. Graduate University of{2., beijing 100039, china 3. The Center for National Spaceborne Demonstration, beijing 100101, china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84.14.Avignon, France 5. National Satellite Meteorological Center, beijing 100081, china 6. State Environmental Protection Administration, beijing 10002., china State key laboratory of Remote Sensing Science Beijing Normal University Chinese Academy of Sciences Beijing 100101 China Graduate University Chinese Academy of Sciences Beijing 100039 China Center for National Spaceborne Demonstration Beijing 100101 China National Satellite Meteorological Center Beijing 100081 China Institut National de la Recherche Agronomique Climat Sol Environnement 84914 Avignon France State Environmental Protection Administration Beijing 100029 China

Based on the laboratory calibration before launch of CBERS-02.IRMSS thermal infrared channel, the onboard blackbody calibration, the radiometric cross- calibration against TERRA MODIS corresponding channel and the in-flight field calibration at Lake Qinghai: water surface radiometric calibration test site of china on Aug. 17, 2.04.are carried out in this research. When making onboard blackbody calibration of CBERS-02.IRMSS, it is necessary to understand inside structures and light path in IRMSS camera and receive and process calibration blackbody signals at normal and high temperatures. Onboard blackbody calibration results of each detector are very important to relative radiometric calibration of images processing and absolute radiometric calibration of each detector. In-flight field calibration mainly contains field experiments, obtaining synchronous images, spectrum marching and MODTRAN radiative transmi- ssion computation. Radiometric cross-calibration of CBERS-02.IRMSS thermal band against TERRA MODIS selected 6 times synchronous images of two sensors passing through Lake Qinghai and Lake Taihu from August to December, 2.04.to compute the cross calibration data. Combining the in-flight field calibration and radiometric cross calibration data, the absolute radiometric calibration coefficients are calculated by the linear regression method. This new calibration model can obviously control the radiometric calibration uncertainties aroused by the single point method used in the in-flight calibration of CBERS-02.IRMSS, this kind of sensors cannot receive the cosmic background radiation. In this research, the radiometric calibration coefficients obtained through the linear regression model are 8.53 (gain, unit: DN/W m?2.r?1μm?1) and 4..92.(offset, unit: DN).

关键词： CBERS-02 IRMSS thermal band in-flight field calibration onboard blackbody calibration cross calibration.

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Grain size record of microparticles in the Muztagata ice core

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Science china Earth sciences 2006年第1期49卷 10-17页

作者： WU Guangjian1,2. YAO Tandong1,2. XU Baiqin1,2. LI Zheng2. TIAN Lide1,2. DUAN Keqin2.& WEN Linke2.1. laboratory of Environment and Process on Tibetan Plateau, Institute of Tibetan Plateau Research, chinese academy of sciences, {2. 100085, china 2. key laboratory of Cryosphere and Environment, Jointly Established by Cold and Arid Regions Environmental and Engi-neering Research Institute and Institute of Tibetan Plateau Research, chinese academy of sciences and chinese academy of Meteorological sciences, china Meteorological Administration, Lanzhou 730000, china laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China key laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou China

The dust transport and sediment characteristics are discussed based onanalysis of mi-croparticle size and size distribution in the Muztagata ice core at 6350 m a.s.I. Thefiner particles with diameter of 1—5 μm are the dominant fraction in number, while middle andcoarse particles mainly contribute to the total volume. The lognormal distribution characteristicscan be seen for some high concentration samples, showing that model size and standard variation aregreater than that in the Greenland ice cores. However, size-volume distribution of some lowconcentration samples is abnormal. Those distributions reflect the dust deposit process in highmountain glaciers at mid-low latitudes and show differences from those in polar ice sheet.

关键词： Muztagata, ice core, microparticle, dust, size distribution.

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The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science china Earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2. CAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4. LIANG Guanglin1& HUANG Jianguo5 1. key laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic {2. and Natural Resources Re-search,{4., beijing 100101, china 2. Institute of Forestry, chinese academy of Forestry {2., beijing 100091, china 3. Department of Civil Engineering, University of Hong Kong, Hong Kong, china 4. Eco-environmental Research Center,{4., beijing 100085, china 5. College of Resources and Environment, Southwest Agricultural University, Chongqing 4.0716, china Correspondence should be addressed to Chen Hao key laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Institute of Forestry Chinese Academy of Forestry Sciences Beijing China Department of Civil Engineering University of Hong Kong Hong Kong China Eco-environmental Research Center Chinese Academy of Sciences Beijing China College of Resources and Environment Southwest Agricultural University Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4. less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2. it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

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Quantum threshold group signature

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Science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1505-1514页

作者： YANG YuGuang1,2.3 & WEN QiaoYan4.1 College of Computer Science and Technology, beijing University of Technology, beijing 10012.,{2. 2.State key laboratory of Integrated Services Network, Xidian University, Xi’an 710071,{2. 3 State key laboratory of Information Security (Graduate University of chinese academy of sciences), beijing 10004.,{2. 4.State key laboratory of Networking and Switching Technology, beijing University of Posts and Tele-communications, beijing 100876,{2. College of Computer Science and Technology Beijing University of Technology Beijing China State key laboratory of Integrated Services Network Xidian University Xi’an China State key laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China State key laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China

In most situations, the signer is generally a single person. However, when the message is written on behalf of an organization, a valid message may require the approval or consent of several persons. Threshold signature is a solution to this problem. Generally speaking, as an authority which can be trusted by all members does not exist, a threshold signature scheme without a trusted party appears more attractive. Following some ideas of the classical Shamir’s threshold signature scheme, a quantum threshold group signature one is proposed. In the proposed scheme, only t or more of n persons in the group can generate the group signature and any t-1 or fewer ones cannot do that. In the verification phase, any t or more of n signature receivers can verify the message and any t-1 or fewer receivers cannot verify the validity of the signature.

关键词： threshold quantum signature trusted party quantum cryptography

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Olfactory receptor gene family evolution in stickleback and medaka fishes

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Science china(Life sciences) 2010年第2期53卷 257-266页

作者： CHEN Ming1,2.PENG ZuoGang1 & HE ShunPing1 1 laboratory of Fish Phylogenetics and Biogeography,Institute of Hydrobiology,chinese {2. of {4.,Wuhan 4.0072.china 2.Graduate University of chinese academy of sciences,beijing 100039,china laboratory of Fish Phylogenetics and Biogeography Institute of Hydrobiology Chinese Academy of Sciences Wuhan China Graduate University of chinese academy of sciences Beijing China

Interaction of olfactory receptor (OR) genes with environmental odors is regarded as the first step of *** this study,OR genes of two fish,medaka (Oryzias latipes) and stickleback (Gasterosteus aculeatus),were identified and an evolutional analysis was *** selection pressure of different TM regions and complete coding region were *** TM regions (TM4.TM5 and TM6) were found to have higher average Ka/Ks values,which might be partly caused by positive selection as suggested by subsequent positive selection *** analysis showed that many PTSs overlap,or are adjacent to previously deduced binding sites in *** results support the hypothesis that binding sites of fish OR genes may evolved under positive selection.

关键词： olfactory receptor positive selection binding site

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