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Scenario simulation and forecast of land use/cover in northern china

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Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2,3.& HE ChunYang 3.1 college of Geographical science, Chongqing Normal university, Chongqing 400047, {3. 2 college of Resources and Environmental science, Chongqing university, Chongqing 400044, {3. 3.college of Resources science & Technology, Beijing Normal university, Beijing 100875, {3. college of Geographical science Chongqing Normal University Chongqing China college of Resources and Environmental science Chongqing University Chongqing China college of Resources science & Technology Beijing Normal University Beijing China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 3. years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

A Raw Signal Simulator for Bistatic SAR

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Chinese Journal of Aeronautics 2009年第4期22卷 434-443页

作者： Xia Weijie,Zhou Jianjiang college of Information science and Technology,nanjing {3. of Aeronautics and Astronautics,nanjing 210016,china college of Information science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

This article proposes a new efficient raw signal simulator for the bistatic synthetic aperture radar （SAR） based on 2D fast Fourier transform （FFT） to deal with cases of both ideal trajectory and trajectory deviation. It begins with analyzing the geometric configuration and the range history of the bistatic SAR in side-looking and squint modes of ideal trajectory as well as trajectory deviation. Then a detailed and mathematical study is conducted on the equivalence relation of bistatic-to-monostatic applications （BTMA） in the case of ideal trajectory and trajectory deviation. Also a set of formulas are derived for the equivalence relation between bistatic SAR and monostatic SAR on some reasonable assumptions. Therefore, the application of the simulation method based on the 2D FFT for the monostatic SAR can be extended to the case of bistatic SAR. Finally, the simulation results prove the validity of this method. By comparing the efficiency of the proposed method with that of the time domain method, it is shown that the former is a few orders of magnitude higher.

关键词： bistatic synthetic aperture radar raw signal simulation fast Fourier transform

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 {3.,nanjing 210004,china 3.Institute of Pediatrics Medicine,nanjing medical {3.,nanjing 210029,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（13. ng/mL,0-24 h）or cultured supernatantfrom 293.T cells transfected with resistin-expressing vectors（13. ng/mL,0-24 h）.Liquid scintillation counting was used to quantitate[3.]2-deoxyglucose *** translocation of insulin-sensitive glucose transporters GLUT4 and GLUT1,synaptosomal-associated protein 23.SNAP23.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 *** SNAP23.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 293.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 SNAP23.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

Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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science china Earth sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2, JIN ZhangDong1 & ZHANG Fei3.1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of sciences, Xi’an 710075, china 2 Graduate university of the Chinese Academy of sciences, Beijing 100049, china 3.college of Resources and Environmental science, nanjing Agricultural university, nanjing 210095, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate university of the Chinese Academy of sciences Beijing China college of Resources and Environmental science Nanjing Agricultural University Nanjing China

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15-55 m) of the Heqing Basin in Yunnan Province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo re- flected the changes in its ambient water composition and ecology; (2) the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3. the molar Sr/Ca ratios were mainly con- trolled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in fu- ture in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

Thermal Insulation and Strength of Autoclaved Light Concrete

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Journal of Wuhan university of Technology(Materials science) 2011年第1期26卷 132-136页

作者：杨若冲吴智深 School of Transportation Southeast University Institute of Urban Engineering science & Technology Southeast University

The primary objective of this study was to develop an autoclaved light concrete （ALC） material with ultra-thermal insulation property and to investigate the relationship between its physical characteristics and mechanical properties. Through tests of dry bulk density and compressive strength, relationship of physical characteristics and mechanical properties of samples were studied, resulting in a material with ultra-thermal insulation property. Scanning electron microscope （SEM） and energy-dispersive X-ray spectroscopy （EDX） were applied to analyze the micro-morphology and elemental composition of samples. To identify the product phases, X-ray diffraction （XRD） was engaged. The test results showed that compressive strength and thermal coefficient were reduced with the increasing of aluminum powder within the mixtures. As a result the optimal thermal coefficient and compressive strength of samples were improved to 0.061 W/（m·k） and 1.2 MPa, respectively. SEM, EDX and XRD analyses showed that calcium silicate hydrate and tobermorite crystal were main resultant phases.

关键词： autoclaved light concrete ultra-thermal insulation microscopic appearance and phase analysis tobermorite crystal

Isoprenaline enhances local Ca2+ release in cardiac myocytes

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Acta Pharmacologica Sinica 2006年第7期27卷 927-932页

作者： Jian-xin SHEN~(2,3.42 Department of Physiology,Shantou university medical college,Shantou 515041,{3. 3.Department of Physiology,medical School of Xi'an Jiaotong university,Xi'an 710061,{3. Department of Physiology Shantou University Medical College Shantou China Department of Physiology Medical School of Xi'an Jiaotong University Xi'an China

Aim:Contraction of cardiac myocytes is controlled by the generation and ampli-fication of intracellular Ca2+*** key step of this process is the couplingbetween sarcolemma L-type Ca2+channels（LCCs）and ryanodine receptors（RyRs）in the sarcoplasmic reticulum（SR）.β-Adrenergic stimulation is an important regu-latory mechanism for this coupling *** the details underlied the globallevel,which require local Ca2+release study are still *** present study isto explore the effects of β-adrenergic stimulation on local Ca2+***:Using confocal microscopy combined with loose-seal patch-clamp approaches,effects of isoprenaline(1 μmol·L-1),a β-adrenergic agonist,on local SR Ca2+re-lease triggered by Ca2+influx through LCCs in intact rat cardiac myocytes ***:Isoprenaline increased the intensity of ensemble averagedlocal Ca2+transients,the peak of which displayed a typical bell-shaped voltage-dependence over the membrane voltages ranging from～-40mV to～+3.m ***-ther analysis showed that this enhancement could be explained by the increasedcoupling fidelity（which refers the increased probability of RyRs activation upondepolarization）,and the increased amplitude of evoked Ca2+sparks(due to moreCa2+releases through local RyRs).In addition,isoprenaline decreased the firstlatency,which displayed a typical"U"-shaped voltage-dependence,showing theavailable acceleration and synchronization of β-adrenergic stimulation on intrac-ellular calcium ***:Isoprenaline enhances local Ca2+release incardiac *** results underscore the importance of regulation of β-adrenergic stimulation on local intermolecular signals between LCCs and RyRs inheart cells.

关键词： local calcium release calcium signaling cardiac myocytes isoprenaline confocal microscopy

A new heuristic algorithm for the circular packing problem with equilibrium constraints

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science china(Information sciences) 2011年第8期54卷 1572-1584页

作者： LIU JingFa 1,2,LI Gang 3.& GENG HuanTong 1 1 School of Computer and Software,nanjing university of Information science & Technology,nanjing 210044,china 2 Network Information Center,nanjing university of Information science & Technology, nanjing 210044,china 3.School of Mathematics and Physics,nanjing university of Information science & Technology,nanjing 210044,china School of Computer and Software Nanjing University of Information Science & Technology Nanjing China Network Information Center Nanjing University of Information Science & Technology Nanjing China School of Mathematics and Physics Nanjing University of Information Science & Technology Nanjing China

The circular packing problem with equilibrium constraints is an optimization problem about simplified satellite module layout design.A heuristic algorithm based on tabu search is put forward for solving this *** algorithm begins from a random initial configuration and applies the gradient method with an adaptive step length to search for the minimum energy *** jump out of the local minima and avoid the search doing repeated work,the algorithm adopts the strategy of tabu *** the process of tabu search,we improve the traditional neighboring solutions,tabu objects and the acceptance criteria of the current solution *** test two sets of benchmarks consisting of 11 representative instances from the current *** numerical results show that the proposed algorithm breaks the records in seven out of 11 instances,and obtains the optimal solutions for the other four instances.

关键词： equilibrium constraints packing problem heuristic algorithm tabu search layout optimization

Low-complexity distributed differential spacetime coding scheme for amplify-and-forward cooperative networks

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science in china(Series F) 2009年第8期52卷 1418-1427页

作者： YU XiangBin1,2, BI GuangGuo3.& XU WeiYe4 1 college of Information science and Technology, nanjing {3. of Aeronautics and Astronautics, nanjing 210016, china 2 Department of Electronic Engineering, City {3. of Hong Kong, Hong Kong, china 3.National Mobile Communications Research Laboratory, southeast university, nanjing 210096, china 4 Department of Communication Engineering, nanjing Institute of Technology, nanjing 211167, china college of Information science and Technology Nanjing University of Aeronautics and Astronautics Nanjing China Department of Electronic Engineering City University of Hong Kong Hong Kong China National Mobile Communications Research Laboratory Southeast University Nanjing China Department of Communication Engineering Nanjing Institute of Technology Nanjing China

By introducing a space-time coding scheme based on amicable orthogonality, we develop a distributed differential space-time coding scheme with the amplify-and-forward （AF） method for wireless cooperative networks. The scheme requires no knowledge of the channel state information at both transmitters and receivers, and effectively decreases the realization complexity due to no channel estimation. Moreover, it has lower decoding complexity and higher coding advantage than the existing scheme, thus avoiding the shortcoming of exponential decoding complexity of some existing schemes. According to the pairwise error probability （PEP） analysis of the system, the power allocations of source and relay terminals are jointly optimized, and as a result, the PEP is minimized, which will provide a helpful guideline for system design. Numerical calculation and simulation results show that the developed scheme is superior to the existing scheme. Moreover, the scheme with optimal power allocation yields obvious performance improvement over that with equal power allocation.

关键词： differential space-time coding cooperative communication amplify-and-forward method power allocation

Stable Skin-specific Overexpression of Human CTLA4-Ig in Transgenic Mice through Seven Generations

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Acta Biochimica et Biophysica Sinica 2006年第3期38卷 171-178页

作者： Yong WANG~1 Yong NI~(1,3. Hong WEI~1* Feng-Chao WANG~2 Liang-Peng GE~1 Xiang GAO~41 Department of Animal science,college of Basic Medicine,Third Military medical {3.,Chongqing 40003.,china 2 Institute of Combined Injury,college of Military Preventive Medicine,Third Military medical {3.,Chongqing 40003.,china 3.School of Life sciences,Southwest {3.,Chongqing 400715,china 4 Animal Model Research Institute,nanjing {3.,nanjing 210093.china Department of Animal science College of Basic Medicine Third Military Medical UniversityChongqing 400038 China School of Life sciences Southwest UniversityChongqing 400715 China Institute of Combined Injury College of Military Preventive Medicine Third Military Medical UniversityChongqing 400038 China Animal Model Research Institute Nanjing UniversityNanjing 210093 China

Skin graft rejection is a typical cellular immune response,mainly mediated by T *** lymphocyte associated antigen 4-immunoglobin (CTLA4-Ig) extends graft survival by blocking the T cellco-stimulation pathway and inhibiting T cell *** investigate the efficacy of CTLA4-Ig in prolong-ing skin graft survival,human CTLA4-Ig (hCTLA4-Ig) was engineered to overexpress in mouse skin bytransgenesis using the K14 *** transcription-polymerase chain reaction (RT-PCR) and West-ern blot assay indicated that the expression of CTLA4-Ig remained skin-specific and relatively constantcompared to the internal control protein,AKT,through seven *** presence and concentrationof the hCTLA4-Ig protein in transgenic mouse sera was determined by enzyme-linked immunosorbent assay(ELISA),and the results indicated that the serum CTLA4-Ig concentration also remained constant *** of transgenic mouse skins grafted onto rat wounds was remarkably prolonged com-pared to that of wild-type skins from the same mouse strain,and remained comparable among all *** suggested that the bioactive hCTLA4-Ig protein was stably expressed in transgenical micethrough at least seven generations,which was consistent with the stable skin-specific CTLA4-Ig *** results demonstrated that the transgenic expression of hCTLA4-Ig in skin driven by the K14 promoterremained constant through generations,and a transgenic line can be established to provide transgenic skinwith extended survival reproducibly.

关键词： cytotoxic T lymphocyte antigen 4-Ig transgenic mice skin K14 promoter