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Repair of spinal cord injury by neural stem cells transfected with brain-derived neurotrophic factor-green fluorescent protein in rats A double effect of stem cells and growth factors?

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Neural Regeneration Research 2010年第17期5卷 1303-1307页

作者： Yansong wang gang Lü Department of Orthopedics First Affiliated Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina

Brain-derived neurotrophic factor（BDNF）can significantly promote nerve regeneration and *** expression of the BDNF-green fluorescent protein（GFP）gene persists for a long time after transfection into neural stem ***,little is known about the biological characteristics of BDNF-GFP modified nerve stem cells in vivo and their ability to induce BDNF expression or repair spinal cord *** the present study,we transplanted BDNF-GFP transgenic neural stem cells into a hemisection model of *** with BDNF-GFP stem cells exhibited significantly increased BDNF expression and better locomotor function compared with stem cells *** therapy with BDNF-GFP transgenic stem cells can improve outcomes better than stem cells alone and may have therapeutic potential for spinal cord injury.

关键词： neural stem cells brain-derived neurotrophic factor transplantation green fluorescent protein spinal cord injury neural regeneration

Dynamic Behavior of Phase Synchronization of Chaos

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Chinese Physics Letters 2000年第5期17卷 332-334页

作者： ZHAN Meng HU gang wang Xin-gang Department of Physics Beijing Normal UniversityBering 100875 China Center for Advanced Science and Technology(CCAST)(World Laboratory) P.O.Box 8730Beijing 100080

The dynamic nature of phase synchronization between chaotic outputs and injected periodic signals is *** find that the collapse of stroboscopic section from global distribution to local one and the loss of homogeneity of stroboscopic sections in chaotic attractors for different phases are the key features of this kind of phase synchronization,meanwhile the overall structure of chaotic attractor is not affected apparently by the phase synchronization.

关键词： chaotic Chaos attractor

贯彻党的十五大精神进一步解放思想抓住机遇发展我国的档案事业

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中国档案 1998年第1期 7-11页

作者：王刚中共中央办公厅国家档案局中央档案馆

贯彻党的十五大精神进一步解放思想抓住机遇发展我国的档案事业搞好农业和农村工作，离不开档案工作的服务和配合。加强档案工作，有利于农业和农村的发展与稳定，有利于农民物质、文化水平的提高。加强农业和农村档案工作，是推进农业... 详细信息

贯彻党的十五大精神进一步解放思想抓住机遇发展我国的档案事业搞好农业和农村工作，离不开档案工作的服务和配合。加强档案工作，有利于农业和农村的发展与稳定，有利于农民物质、文化水平的提高。加强农业和农村档案工作，是推进农业现代化的需要，是保持农村稳定与发展...

关键词：档案事业农业十五大农村档案《档案法》抓住机遇解放

Multi-scale nature of non-blade-order propagating flow disturbances in axial compressors

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Chinese Journal of Aeronautics 2022年第9期35卷 129-142页

作者： Hao wang Yan’gang wang Hanru LIU Fei XUE Zhongnan wang School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China College of Engineering and Physical Sciences University of BirminghamBirmingham B152TTUnited Kingdom

Non-blade-order flow disturbances, also referred to as pre-stall disturbances or tip flow unsteadiness, are closely related with compressor instabilities. The present work provides a comprehensive investigation on multi-scale nature of non-blade-order disturbances and the underlying flow physics in axial compressors. By applying full-annulus Unsteady Reynolds-Averaged Navier-Stokes(URANS) simulations, along with space–time correlation and spatial Fourier decomposition, to the disturbed pressure, the propagating feature of the non-blade-order disturbances is obtained. Further, a bridge between non-blade-order disturbances and the evolution of unsteady vortex has been set up. The results show that non-blade-order disturbances, featured as short-length-scale(35 modes across annulus), first appear as the occurrence of tip leakage vortex fluctuation, while the compressor still operates far from stall. Leading-edge radial vortex appears at near stall condition, and its movement induces a circumferential propagating disturbance overlaying on the one induced by oscillating tip leakage vortex. The interaction of the short-scale disturbances with a lowamplitude long-scale(of circumference) disturbance is observed, which results in disturbances with multiple scales of consecutive spatial modes, along with multiple frequency peaks in spectra. The compressor falls into stall as the circumferential nonuniform scattering of the leading-edge vortexes occurs. The densely-and sparsely-scattered leading-edge radial vortexes induce a high-amplitude long-scale(of circumference) disturbance , i.e. stall disturbance.

关键词： Axial compressors Flow instabilities Multi-scale disturbances Stall Unsteady flow

Numerical simulation and optimized design of cased telescoped ammunition interior ballistic

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Defence Technology（防务技术） 2018年第2期14卷 119-125页

作者： Jia-gang wang Yong-gang Yu Liang-liang Zhou Rui Ye School of Energy and Power Engineering Nanjing University of Science and Technology Chongqing wangjiang Industry Co. Ltd

In order to achieve the optimized design of a cased telescoped ammunition(CTA) interior ballistic design,a genetic algorithm was introduced into the optimal design of CTA interior ballistics with coupling the CTA interior ballistic model. Aiming at the interior ballistic characteristics of a CTA gun, the goal of CTA interior ballistic design is to obtain a projectile velocity as large as possible. The optimal design of CTA interior ballistic is carried out using a genetic algorithm by setting peak pressure, changing the chamber volume and gun powder charge density. A numerical simulation of interior ballistics based on a 35 mm CTA firing experimental scheme was conducted and then the genetic algorithm was used for numerical optimization. The projectile muzzle velocity of the optimized scheme is increased from 1168 m/s for the initial experimental scheme to 1182 m/s. Then four optimization schemes were obtained with several independent optimization processes. The schemes were compared with each other and the difference between these schemes is small. The peak pressure and muzzle velocity of these schemes are almost the same. The result shows that the genetic algorithm is effective in the optimal design of the CTA interior ballistics. This work will be lay the foundation for further CTA interior ballistic design.

关键词： Cased telescoped ammunition Interior ballistics Gunpowder Optimization genetic algorithm

Geochronology and Geochemistry of Mafic Rocks in the Xuhe, Shaanxi, China: Implications for Petrogenesis and Mantle Dynamics

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Acta Geologica Sinica(English Edition) 2015年第1期89卷 187-202页

作者： wang Kunming wang Zongqi ZHANG Yingli wang gang MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral Resources CAGS

The Xuhe mafic rocks, located in Ziyang county of Shaanxi Province, are dominated by diabase-porphyrite, gabbro-diabase, diabase, and pyroxene diorite. Primitive mantle-normalized multi-element patterns show that, the Xuhe marie rocks are enriched in large ion lithophile elements （LITE）, such as Ba and Pb, depleted in K and Sr for basic rocks, and are depleted in Sr, P and Ti for pyroxene diorite. Chondrite-normalized REE patterns display LREE enrichment （LaN/YbN = 9.34- 13.99） and have normalized patterns for trace element and REE similar to that of typical OIB. Detailed SIMS zircon U-Pb dating yields emplacement ages of 438.4 ± 3.1 Ma for Xuhe mafic rocks. The relatively low MgO （basic rock： 3.11-7.21 wt%; pyroxene diorite： 0.89-1.21 wt% ） and Mg# （0.20- 0.49） for Xuhe mafic rocks suggest that they were possibly originated from an extremely evolved magma. The rising parental mafic magmas underwent pyroxene and plagioclase fractionation. Crustal contamination of pyroxene diorite before emplacement occurred at a higher crustal level compared to other lithology in Xuhe mafic rocks. The degree of partial melt was low （5%-10%） and in garnetspinel transition facies. Sr-Nd isotope of pyroxene diorite and enrichment mantle characteristics for Xuhe mafic rocks suggest that mafic rocks in the North Daba Mountains were derived from a mixture of HIMU, EMII and small amount of EMI components. Furthermore, this study discusses mantle geodynamic significance of Xuhe mafic rocks in the Silurian, which indicates subduction and uplift of magma caused back-arc extension.

关键词： Xuhe mafic rock SIMS U-Pb chronology geochemistry petrogenesis mantle dynamic

Zircon Geochronology and Trace Element Geochemistry from the Xiaozhen Copper Deposit, North Daba Mountain: Constraints on Albitites Petrogenesis

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Acta Geologica Sinica(English Edition) 2014年第1期88卷 113-127页

作者： wang gang wang Zongqi ZHANG Yingli wang Kunming School of Earth Sciences and Resources China University of Geosciences Institute of Mineral Resources Chinese Academy of Geological Sciences

Albitite often accompanies with various metal and gem mineral deposits and a large number of occurrences have been reported globally, including the South Qinling orogen, China. The Xiaozhen copper deposit is a typical deposit in the North Daba Mountain area of the South Qinling orogen whose distribution is controlled by albitite veins and fractures. As there are few studies on the petrogenesis of albitite in Xiaozhen copper deposit, this paper focuses on the petrogenesis of albitite and its mineralization age. Detailed fieldwork and mineral microscopic observations initially suggest that albitite from the Xiaozhen copper deposit is igneous in origin. Further zircon trace element geochemistry studies indicate that these zircons have high Th/U ratios（〉0.5）, low La content, high（Sm/La）N and Ce/Ce＊values, and a strong negative Eu anomaly, which are commonly seen in magmatic zircons. The chondrite–normalized rare earth element（REE） patterns are consistent with magmatic zircons from throughout the world, and they fall within or near the field of magmatic zircons on discriminant diagrams. The calculated average apparent Ti–in–zircon temperature for young zircons is 780°C, consistent with magmatic zircon crystallization temperatures. Therefore, zircon geochemistry indicates that the albitite origin is magmatic. SIMS U–Pb dating on nine magmatic zircons yielded a concordia age of 154.8±2.2 Ma, which represents the formation of albitite and the metallogenic age. More importantly, it is consistent with the ages of Yanshanian magmatism and metallogenesis in the South Qinling orogen, so formation of the Xiaozhen copper deposit may be a closely related geological event.

关键词： Albitite petrogenesis SIMS zircon geochronology zircon trace element geochemistry Xiaozhen copper deposit North Daba Mountain

Numerical simulation of time delay interferometry for TAIJI and new LISA

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Research in Astronomy and Astrophysics 2019年第4期19卷 95-108页

作者： gang wang Wei-Tou Ni INFN Gran Sasso Science Institute INFN Sezione di PisaEdificio CLargo Bruno Pontecorvo National Astronomical Observatories Chinese Academy of Sciences State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of Sciences

The success of LISA Pathfinder in demonstrating the LISA drag-free requirement paved the way for using space interferometers to detect low-frequency and middle-frequency gravitational waves(GWs). The TAIJI GW mission and the new LISA GW mission propose using an arm length of 3 Gm(1 Gm = 10~6 km) and an arm length of 2.5 Gm respectively. For a space laser-interferometric GW antenna,due to astrodynamical orbit variation, time delay interferometry(TDI) is needed to achieve nearly equivalent equal-arms for suppressing the laser frequency noise below the level of optical path noise, acceleration noise, etc in order to attain the requisite sensitivity. In this paper, we simulate TDI numerically for the TAIJI mission and the new LISA mission. To do this, we work out a set of 2200-day(6-year) optimized science orbits for each mission starting on 2028 March 22 using the CGC 2.7.1 ephemeris framework. Then we use the numerical method to calculate the residual optical path differences of the first-generation TDI configurations and the selected second-generation TDI configurations. The resulting optical path differences of the second-generation TDI configurations calculated for TAIJI, new LISA and eLISA are well below their respective requirements for laser frequency noise cancelation. However, for the first-generation TDI configurations, the original requirements need to be relaxed by 3 to 30 fold to be satisfied. For TAIJI and the new LISA, about one order of magnitude relaxation would be good and recommended; this could be borne on the laser stability requirement in view of recent progress in laser stability, or the GW detection sensitivities of the second-generation TDIs have to be used in the diagnosis of the observed data instead of the commonly used X, Y and Z TDIs.

关键词： gravitational waves methods:numerical techniques:interferometric

NADPH oxidase and reactive oxygen species as signaling molecules in carcinogenesis

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Frontiers of Medicine 2009年第1期3卷 1-7页

作者： gang wang Division of Neurobiology Department of Neurology and NeuroscienceWeill Cornell Medical CollegeCornell UniversityNew YorkNY 10021USA

Reactive oxygen species(ROS)are small molecule metabolites of oxygen that are prone to participate in redox reactions via their high *** ROS could be generated in reduced nicotina-mide-adenine dinucleotidephosphate(NADPH)oxidase-dependent and/or NADPH oxidase-independent ***,ROS are involved in many signaling cascades that contribute to normal *** classical example is that ROS derived from the NADPH oxidase and released in neurotrophils are able to digest invading *** ROS,however,contribute to patho-genesis of various human diseases including cancer,aging,dimentia and *** signaling messengers,ROS are able to oxidize many targets such as DNA,proteins and lipids,which may be linked with tumor growth,invasion or *** present review summarizes recent advances in our comprehensive understanding of ROS-linked signaling pathways in regulation of tumor growth,invasion and metastasis,and focuses on the role of the NADPH oxidase-derived ROS in cancer pathogenesis.

关键词： free radicals tumor phox cell proliferation cancer therapy