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Trace element geochemistry of the Lower Cambrian black rock series from northwestern Hunan, South china

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Progress in Natural Science:Materials International 2004年第1期14卷 65-71页

作者： PAN Jiayong 1,2. *, MA Dongsheng 1 and CAO Shuanglin 1,2. (1.The State Key Laboratory for Mineral Deposits Research, nanjing University, nanjing 2.0093, {2. 2. East {2. institute of Technology, Fuzhou 344000, {2.) nanjing Univ State Key Lab Mineral Deposit Res Nanjing 210093 Peoples R China E china Inst Technol Fuzhou 344000 Peoples R China

Samples of black rock series collected from the Lower Cambrian Niutitang Formation, northwestern Hunan Province, china, were analyzed for trace elements. The trace element geochemical characteristics of the ore layer (high enrichments of Ni, Mo, V, U, Cu, Pb, Zn, Cd, Tl and Ba; high U/Th ratios and LREE enriched patterns with positive Eu and Y anomalies) support the assumption that the Ni Mo polymetallic layer is of submarine hydrothermal origin. High field strength elements (HFSE) and lithophile elements such as Nb, Ta, Zr, Hf, Li, Be, Rb, Cs, Th and Sc are remarkably higher in the upper unit than those in the lower unit of the Niutitang Formation. These features may reflect that hydrothermal contributions were diminished, and terrigenous constituents were increased in the sediments of the upper unit of the Niutitang Formation.

关键词： black rock series Early Cambrian trace elements northwestern Hunan china

Case studies on mesoscale structures of heavy rainfall system in the Yangtze River generated by Meiyu front

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Science china Earth Sciences 2005年第8期48卷 1303-1311页

作者： LIU Liping1, RUAN Zheng1 & QIN Danyu2.1. Chinese Academy of Meteorological Sciences, Beijing 100081, china 2. nanjing {2. of Meteorology, nanjing 2.0044, china Chinese Academy of Meteorological Sciences Beijing China nanjing institute of Meteorology Nanjing China

A heavy rainfall system was observed over the Yangtze River during Meiyu season by using dual-Doppler radar systems in the field experiment conducted by the project of National Fundamental Research Planning “Research on formation mechanism and the prediction theory of hazardous weather over china”. The three-dimensional mesoscale kinematic structure and process of a heavy rain on 2. and 2. July, 2.02.are investigated by using the radial velocity and dual-Doppler radar technique. The results show that a southwest-northeast oriented rain band with the length of about 1000 km involves numbers of meso-β or meso-γ-scale convective cells with the size of 2.―50 km. The heavy rain band in the middle reaches of the Yangtze River ex-ists in a low-level wind shear. The interaction between southwest low-level jet on the southern side of wind shear and east wind on the northern side formed the updraft. The wind disturbance, wind shear and convergence generate the convective action. The new cell developed in right rear flank of rain band and moved to the southwest wind area, where the vapor is abundant. This kind of echo can last a long time and developed well. The strong convective echoes are often ac-companied by the meso-γ-scale vortex and convergence.

关键词： heavy rainfall in Meiyu front, mesoscale structure, dual-Doppler radar, middle reaches of the Yangtze River, low-level jet.

A new sequential learning algorithm for RBF neural networks

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Science china(Technological Sciences) 2004年第4期47卷 447-460页

作者： YANG Ge1, LV Jianhong1 & LIU Zhiyuan2.1. Department of Power Engineering, Southeast University, nanjing 2.0096, china 2. Department of Power Engineering, nanjing institute of Technology, nanjing 2.0013, china Department of Power Engineering Southeast University Nanjing China Department of Power Engineering Nanjing Institute of Technology Nanjing China

Due to their inherent imperfections, it is hard to use the static neural networks for nonlinear time-varying process modeling and prediction, and the minimal resource allocation network (MRAN) is difficult to be realized for its too many regulation parameters. A new sequential learning algorithm for radial basis function (RBF) neural networks based on local projection named Local Projection Network (LPN) is proposed in this paper. The results of validation for several benchmark problems with the new algorithm show that the presented LPN not only has the same level as M-RAN in network size and precision of the outputs, but also has fewer regulation parameters and is more predictable.

关键词： radial basis functions, local projection network, minimal resource allocation network, learning algorithm.

Discovery of sponge body fossils from the late Meishucunian (Cambrian) at Jinsha, Guizhou, south china

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Progress in Natural Science:Materials International 2005年第8期15卷 708-712页

作者： YANG Xinglian 1,2., ZHAO Yuanlong2. WANG Yue2.and WANG Pingli2.1. nanjing institute of Geology and Palaeontology, Chinese Academy of Sciences, nanjing 2.0008, china 2. institute of Resource and Environment, Guizhou University, Guiyang 550003, china) nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China institute of Resource and Environment Guizhou University Guiyang 550003 China

Here we report discovery of a sponge body fossil Triticispongia sp. from the base of lower Cambrian Niutitang Formation at Jinsha, Guizhou. Stratigraphically, the fossil horizon is located below Ni-Mo ore layer with the Niutitang Biota above, and is equivalent to the late Meishucunian. The species is global in shape with skeletons composed of stauractins and monaxons. Triticispongia sp. reported here may be the earliest sponge body fossils of Cambrian, which provides new information for understanding early evolution and radiation of sponge animals.

关键词： sponges Cambrian Niutitang Formation Guizhou china.

Prolonged exposure to resistin inhibits glucose uptake in rat skeletal muscles

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Acta Pharmacologica Sinica 2007年第3期28卷 410-416页

作者： Hong-qi FAN~(2.3) Nan GU~(2.3) Feng LIU~2.Li EEI~2.Xiao-qin PAN~2.Mei GUO~2.Rong-hua CHEN~(2.4) Xi-rong GUO~(2.3,4)2.Department of Pediatrics,nanjing Maternal and Child Health Hospital of nanjing Medical University,nanjing 2.0004,china 3 institute of Pediatrics Medicine,nanjing Medical University,nanjing 2.002.,china Department of Pediatrics Nanjing Maternal and Child Health Hospital of Nanjing Medical University Nanjing China institute of Pediatrics Medicine Nanjing Medical University Nanjing China

Aim:To assess the effects and mechanisms of the action of resistin on basal andinsulin-stimulated glucose uptake in rat skeletal muscle ***:Rat myo-blasts（L6）were cultured and differentiated into myotubes followed by stimula-tion with single commercial resistin（130 ng/mL,0-2. h）or cultured supernatantfrom 2.3-T cells transfected with resistin-expressing vectors（130 ng/mL,0-2. h）.Liquid scintillation counting was used to quantitate[3H]2.deoxyglucose *** translocation of insulin-sensitive glucose transporters GLUT4 and GLUT1,synaptosomal-associated protein 2.（SNAP2.）and GLUT protein content,as wellas the tyrosine phosphorylation status and protein content of insulin receptorsubstrate（IRS）-1,were assessed by Western ***:Treatment of L6myotubes with single resistin or cultured supernatant containing recombinantresistin reduced basal and insulin-stimulated 2.deoxyglucose uptake and impairedinsulin-stimulated GLUT4 *** SNAP2. protein content wasdecreased,no effects were noted in GLUT4 or GLUT1 protein *** diminished insulin-stimulated IRS-1 tyrosine phosphorylation levels withoutaffecting its protein *** effects of recombinant resistin from 2.3-T cellstransfected with resistin-expressing vectors were greater than that of single ***:Resistin regulated IRS-1 function and decreased GLUT4translocation and glucose uptake in response to *** downregulatedexpression of SNAP2. may have been partly attributed to the decrease of glucoseuptake by resistin *** observations highlight the potential role ofresistin in the pathophysiology of type 2.diabetes related to obesity.

关键词： resistin insulin glucose uptake obesity diabetes

Schmeissneria:An angiosperm from the Early Jurassic

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Journal of Systematics and Evolution 2010年第5期48卷 326-335页

作者： 1,2.in WANG 1(nanjing institute of Geology and Palaeontology,Chinese Academy of Sciences,nanjing 2.0008,china) 2.Fairylake Botanical Garden,Shenzhen 518004,china) (nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China) (Fairylake Botanical Garden Shenzhen 518004 China)

The origin of angiosperms has been a focus of intensive research for a long *** so-called pre-Cretaceous angiosperms,including Schmeissneria,are usually clouded with *** expel the cloud around the enigmatic Schmeissneria,the syntype and new materials of Schmeissneria collected previously in Germany and recently in china are *** materials include female inflorescences and *** latter are old materials but were under-studied *** microscopy and scanning electron microscope observations indicate that the fruits in these infructescences have in situ seeds enclosed,and that the ovaries are closed be fore *** the plants meet two strict criteria for angiosperms:angiospermy plus *** Schmeissneria in angiosperms will extend the record of angiosperms up to the Early Jurassic,more compatible with many molecular dating conclusions on the age of angiosperms,and demanding a reassessment of the current doctrines on the origin of *** the phylogenetic relationship of Schmeissneria to other angiosperms apparently is still an open question,this study adds to research concerning the origin of angiosperms.

关键词： angiosperm earliest evolution flower fossil Germany Jurassic origin.

On critical values concerning the evolution of the long period families

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Chinese Journal of Astronomy and Astrophysics 2009年第4期9卷 494-500页

作者： Xi-Yun Hou1,2. Astronomy Department, nanjing University, nanjing 2.0093, {2. 2.institute of Space Environment and Astronautics, nanjing University, nanjing 2.0093, {2. Astronomy Department Nanjing University Nanjing 210093 China institute of Space Environment and Astronautics Nanjing University Nanjing 210093 China

In a previous paper, we proposed another special critical value concerning the evolution of the long period family around the equilateral equilibrium points, besides the two values given by Henrard. Are there any other special critical values？ After studying the stability curves of the long period family carefully, we gave a negative answer. During the study, we found an interesting family of periodic orbits which we called the homo family. We studied the evolution of this family following the increase of μ. With these findings, we were able to explain the origin of the four branches of periodic families emanating from L4 and the stability results of the equilateral equilibrium points.

关键词： celestial mechanics

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Science china Chemistry 2004年第6期47卷 466-479页

作者： SONG Huajie1,2. XIAO Heming1 & DONG Haishan2.1. Department of Chemistry, nanjing University of Science and Technology, nanjing 2.0094, {2. 2. institute of Chemical Materials, {2. Academy of Engineering Physics, Mianyang 62.900, {2. Department of Chemistry Nanjing University of Science and Technology Nanjing China institute of Chemical Materials China Academy of Engineering Physics Mianyang China

The symmetry-adapted perturbation theory (SAPT) that has the ability in decompo- sition of the total interaction energy into physically meaningful components is used to provide a more fundamental understanding of intermolecular forces. This work was motivated by the diffi- culty of standard SAPT in computing the intermolecular interactions for large energetic dimer systems. SAPT based on Kohn-Sham orbitals (SAPT(DFT)) proves computationally efficient for these large systems, but has been shown to perform poorly for interaction energy components. The deficiencies of SAPT(DFT) result from wrong asymptotical behaviors of commonly used exchange-correlation potentials. To remove the deficiencies, two asymptotic corrections by means of van Leeuwen and Baerends (LB) model potential and Fermi-Amaldi (FA) type potential were applied into three small test systems comprising He2. HF2.and (N2.2.and a set of larger ni- tramide dimers at several separations. The results showed that when utilizing newly developed frequency-dependent density susceptibilities (FDDS) technique for computing dispersion energy, the FA asymptotic correction is very effective to circumvent these deficiencies in SAPT(DFT) and yields a good accuracy over the LB correction. The FA corrected SAPT(DFT) approach is capa- ble of correctly predicting all the quantitative trends in binding energies for all test cases and substantially reduces computational cost as compared with the standard SAPT calculations. The successful application of the approach to nitramide dimer demonstrates that it potentially pro- vides a good means to calculate accurately intermolecular forces in larger system such as en- ergetic systems.

关键词： intermolecular interaction, density functional theory (DFT), symmetry adapted perturbation theory (SAPT), asymptotic correction, frequency-dependent density susceptibilities (FDDS).

Seasonal variation of global stratosphere-troposphere mass exchange

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Progress in Natural Science:Materials International 2007年第12期17卷 1466-1475页

作者： Guo Dong1,2. Lu Daren2.and Sun Zhaobo1(1. institute of Atmospheric Sciences, nanjing University of Information Science and Technology, {2., china 2. LAGEO, institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., china) institute of Atmospheric Sciences Nanjing University of Information Science and Technology Nanjing 210044 China LAGEO Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

By Wei formula in pressure coordinate, the stratosphere-troposphere mass exchange (STME) is diagnosed globally for 44 years from 1958 to 2.01 using the European Center for Medium-Range Weather Forecasts (ECMWF) reanalysis datasets. Regions of mass flux into the stratosphere are found over Indonesia, bay of Bangladesh and the mid-west coast of South Africa. Compensating mass outflow from the stratosphere appears mainly over mid-latitudes near large-scale troughs. Upward and downward transport of mass at the middle and high latitudes accompany with each other. Mass flux into troposphere is stronger in autumn and winter than in spring and summer. Strong downward mass flux into the troposphere occurs in eastern Asia the whole year with nearly stable sites. Although the area of eastern Asia accounts for only 5.6% of that of the northern hemisphere (NH), its net mass exchange reaches 15.83% of that of the NH, which means that research on STME of eastern Asia is greatly important to that of the NH and even the global areas. Air across the tropopause enters more from stratosphere to troposphere than that from troposphere to stratosphere, which is possibly related with systematic bias of the assimilated datasets and with persistent rise of the tropopause height. Contributions of the mass exchange and the mass flux exchange in the NH and southern hemisphere (SH) on their latitudes increase from equator to pole, with larger contributions in the NH. Mass exchange and mass flux exchange per areas at high latitudes are larger than that at low latitudes, which means greater mass exchange efficiency at high latitudes.

关键词： stratosphere troposphere mass exchange seasonal variation.