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Long-term surface water changes and driving cause in Xiong'an,China:from dense Landsat time series images and synthetic analysis

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Science Bulletin 2018年第11期63卷 708-716页

作者： Chunqiao Song Linghong Ke Hang pan Shengan zhan Kai Liu Ronghua Ma Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China Department of Geography University of CaliforniaLos AngelesLos AngelesCA 90095United States School of Earth Sciences and Engineering Hohai UniversityNanjing 211100China Department of Geographic Information Science Nanjing UniversityNanjing 210023China

China＇s government statement recently reported the plan of constructing Xiong＇an New Area, which aims to phase out some extra capital functions from Beijing and to explore an innovative urban development mode with the priority in eco-environmental protection. The New Area is located in the semi-arid North China Plain （NCP） and is home to NCP＇s largest natural freshwater wetland, Baiyangdian Lake. A comprehensive realization of surface water dynamics would be crucial for policy-makers to outline a sustainable environment development strategy for New Area. In this study, we used a total of 245 time slices of cloud-free Landsat images to document the continuous changes of water bodies within Xiong＇an City dur- ing 1984-2016 and to provide detailed evidence of water presence and persistency states and changes under the influences of climate change and human actions. Our results reveal that the New Area water body areas varied dramatically during the past 33 years, ranging from 0.44 km^2 in April 1988 to 317.85 km^2 in February 1989. The change of surface water area was not characterized by a monotonically decreasing tendency. The evolution processes can be divided into four sub-stages： the first extreme desiccation in mid-1980s, the wet stage with the most extensive inundation areas and strong inter-annual fluctuations from late-1988 to late 1999, another desiccation stage in early 2000s, and the overall recovering stage between 2007 and 2016. We also mapped the maximum water inundation extents and frequencies of all-season, pre-wet season （February-May） and post-wet season （September-December） for the 33 years and different sub-periods. Although there is good agreement between time series of surface water area evolution in the New Area and station-based precipitation and evaporation variations, multipie lines of evidences reviewed in previous research indicate that the degraded Baiyangdian Lake was also tightly associated with human activities from various aspects, inc

关键词： Xiong'an New Area Surface water Baiyangdian Lake Remote sensing Climate change Landsat

High resolution bathymetry of China seas and their surroundings

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Chinese Science Bulletin 2001年第19期46卷 1661-1664页

作者： yong Wang Houze Xu Jigang zhan Chinese Acad Sci Inst Geodesy & Geophys Wuhan Peoples R China

Based on the oceanic lithospheric flexure and the worldwide bathymetric data ETOPO5, the high resolution bathymetry of the China seas and their surroundings is computed from altimeter derived gravity anomalies. The new bathymetry obtained by this study is higher resolution and accuracy than the widely used ETOPO5 data, meanwhile it shows clearly the seafloor, the tectonic characteristics and the geodynamical processes in the China seas.

关键词： China seas altimetry gravity anomalies bathymetry.

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线粒体自噬在特发性肺纤维化中的生物学机制

中国组织工程研究 2025年第31期29卷 6708-6716页

作者：谢铱子林雪莹张欣欣黄秀芳詹少锋江勇蔡彦广州中医药大学第一临床医学院广东省广州市510000 广州中医药大学第一附属医院广东省广州市510000 广州中医药大学岭南医学研究中心广东省广州市510000 广东省中医临床研究院广东省广州市510000 深圳市中西医结合医院广东省深圳市518104 广东省中医院珠海医院广东省珠海市519015

背景:线粒体自噬与特发性肺纤维化的发生发展关系密切,但其作用机制尚不清楚。目的:探讨线粒体自噬在特发性肺纤维化中的生物学机制,为临床特发性肺纤维化风险预测及亚型区分提供思路。方法:通过GEO和Reactome Pathway数据库等获取特发... 详细信息

背景:线粒体自噬与特发性肺纤维化的发生发展关系密切,但其作用机制尚不清楚。目的:探讨线粒体自噬在特发性肺纤维化中的生物学机制,为临床特发性肺纤维化风险预测及亚型区分提供思路。方法:通过GEO和Reactome Pathway数据库等获取特发性肺纤维化的线粒体自噬相关基因,基于组间差异、随机森林模型筛选特发性肺纤维化的线粒体自噬特征基因。采用g:Profiler数据库进行GO功能富集分析和KEGG、Reactome、WIKI通路富集分析。通过共识聚类法区分特发性肺纤维化线粒体自噬亚型,进行亚型间免疫浸润分析,并筛选出线粒体自噬关键基因。最后,通过列线图模型量化线粒体自噬关键基因对临床特发性肺纤维化发生风险的预测价值,并探索线粒体自噬关键基因与特发性肺纤维化临床特征的相关性。结果与结论:①特发性肺纤维化中与线粒体自噬相关的基因共13个,经组间差异、随机森林模型筛选出线粒体自噬特征基因5个,分别是PINK1、RPS27A、SRC、HIF1A和CDH6;②GO分析主要涉及泛素蛋白连接酶结合、细胞对缺氧的反应;通路富集分析主要涉及PINK1-PRKN介导的线粒体自噬、NOTCH信号通路、EGFR的信号传递和血管生成等;③HIF1A在不同特发性肺纤维化亚型间具有显著的表达差异,可能成为特发性肺纤维化线粒体自噬亚型区分的关键基因;④免疫浸润分析提示骨髓来源抑制性细胞、中性粒细胞与1型辅助性T细胞可能在不同亚型之间存在浸润差异,而HIF1A与多种免疫细胞浸润程度呈正相关;⑤列线图模型提示通过HIF1A的表达水平可能预测临床特发性肺纤维化的发生风险;⑥临床特征分析提示,HIF1A高表达患者可能肺功能更差,纤维化程度更严重。结果表明,PINK1、RPS27A、SRC、HIF1A和CDH6可能通过线粒体自噬影响特发性肺纤维化的发生发展,其中HIF1A可能成为特发性肺纤维化风险预测及临床亚型区分的关键基因,且与患者的肺功能水平密切相关。

关键词：特发性肺纤维化线粒体自噬自噬关键基因亚型分析富集分析免疫浸润分析肺功能生物信息学

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Optimal configuration for vibration frequencies in a ring of harmonic oscillators： The nonidentical mass effect

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Frontiers of physics 2015年第3期10卷 89-100页

作者： Shuai Liu Guo-yong zhang Zhiwei He Meng zhan College of Science Northwest A&F University Yangling 712100 China Wuhan Center for Magnetic Resonance State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China College of Computer Science and Technology Hubei Normal University Huangshi 435002 China University of the Chinese Academy of Sciences Beijing 100049 China

The parameter diversity effect in coupled nonidentical elements has attracted persistent interest in nonlinear dynamics. Of fundamental importance is the so-called optimal configuration problem for how the spatial position of elements with different parameters precisely determines the dynamics of the whole system. In this work, we study the optimal configuration problem for the vibration spectra in the classical mass-spring model with a ring configuration, paying particular attention to how the configuration of different masses affects the second smallest vibration frequency （ω2） and the largest one （ωN）. For the extreme values of ω2 and ωN, namely, （ω2）min, （ω2）max, （ωN）min, and （ωN）max, we find some explicit organization rules for the optimal configurations and some approximation rules when the explicit organization rules are not available. The different distributions of ω2 and ωN are compared. These findings are interesting and valuable for uncovering the underlying mechanism of the parameter diversity effect in more general cases.

关键词： synchronization vibration frequencies normal modes complex systems

Quantum Effects of Mesoscopic Inductance and Capacity Coupling Circuits

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Communications in Theoretical Physics 2006年第6期45卷 1126-1130页

作者： LIU Jian-Xin AN zhan-Yuan SONG yong-Hua Department of Electrical Engineering North China Electric Power University Baoding 071003 China Department of Applied Physics North China Electric Power University Baoding 071003 China Electronic and Computer Engineering Department Brunel University London UK

Using the quantum theory for a mesoscopic circuit based on the discretenes of electric charges, the finitedifference Schrodinger equation of the non-dlssipative mesoscopic inductance and capacity coupling circuit is achieved. The Coulomb blockade effect, which is caused by the discreteness of electric charges, is studied. Appropriately choose the components in the circuits, the finlte-dlfference Schrodinger equation can be divided into two Mathieu equations in representation.＂ With the WKBJ method, the currents quantum fluctuations in the ground states of the two circuits are calculated. The results show that the currents quantum zero-point fluctuations of the two circuits are exist and correlated.

关键词： mesoscopic circuit Mathieu equation quantum effect

HBV DNA vaccine with adjuvant cytokines induced specific immune responses against HBV infection

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World Journal of Gastroenterology 2003年第1期9卷 108-111页

作者： De-WeiDu zhan-Shengjia Guang-YuLi yong-YingZhou DepartmentofInfectiousDiseases TangduHospitalFourthMilitaryMedicalUniversity'Xi'an710038ShaanxiProvinceChina DepartmentofInfectiousDiseases TangduHospitalFourthMilitaryMedicalUniversity'Xi'an710038ShaanxiProvinceChina

AIM:To seek for an effective method to improve the immune responses induced by DNA vaccine expressing HBV surface antigen(pCR3.1-S)in Balb/c mice(H-2~d). METHODS:The pCR3.1-S plasmid and the eukaryotic expression vectors expressing murine IL-2(pDOR-IL-2)or IL-12(pWRG3169)were injected into mice subcutaneously. The immune responses to pCR3.1-S and the adjuvant effect of the cytokines plasmid were *** the effect of pCR3.1-S on anti-translated subcutaneous tumor of P815 mastocytoma cells stably expressing HBsAg(P815-HBV-S) was also ***-HBs in serum was detected by enzyme- linked immunoadsordent assay(ELISA)and HBsAg specific cytotoxic T lymphocytes(CTLs)activity was measured by ^(51)Cr release *** three weeks of DNA immunization,the cells of P815-HBV-S were inoculated into mice subcutaneously and the tumor growth was measured every five *** survival rate and living periods of mice were also calculated. RESULTS:After 8 wk DNA immunization,the A 450 nm values of sera in mice immunized with pCR3.1,pCR3.1-S and pCR3.1-S codeliveried with IL-2 or IL-12 plasmids were 0.03+0.01,1.24±0.10,1.98±0.17 and 1.67±0.12 *** in mice codeliveried pCR3.1-S with IL-2 or IL-12 plasmids were significantly higher than that of mice injected pCR3.1 or pCR3.1-S *** HBsAg specific CTL activities in mice coinjected with pCR3.1-S and IL-2 or IL- l2 eukaryotic expression vectors were(61.9±7.1)% and (73.3±8.8)%,which were significantly higher than that of mice injected with pCR3.1(10.1±2.1)% or pCR3.1-S(50.5 ±6.4)%.The HBsAg specific CTL activities in mice injected with pCR3.1,pCR3.1-S,pCR3.1-S combined with IL-2 or IL- l2 eukaryotic expression vectors decreased significantly to (3.2±0.8)%,(10.6±1.4)%,(13.6±1.3)% and(16.9±2.3) % respectively after the spleen cells were treated by anti- CD8^+ monoclonal antibody,but presented no significant change to anti-CD4^+ monoclonal antibody or unrelated to monoclonal *** HBV-S DNA vaccine(pCR3.1-S

关键词：乙型肝炎 HBV-DNA疫苗免疫反应细胞因子酶联免疫法

THE WALL EFFECT ON VENTILATED CAVITATING FLOWS IN CLOSED CAVITATION TUNNELS

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Journal of Hydrodynamics 2008年第5期20卷 561-566页

作者： CHEN Xin LU Chuan-jing LI Jie pan zhan-cheng Department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China

For ventilated cavitating flows in a closed water tunnel, the wall effect may exert an important influence on cavity shape and hydrodynamics, An isotropic mixture multiphase model was established to study the wall effect based on the RANS equations, coupled with a natural cavitation model and the RNG k-ε turbulent model. The governing equations were discretized using the finite volume method and solved by the Gauss-Seidel linear equation solver on the basis of a segregation algorithm. The algebraic multigrid approach was carried through to accelerate the convergence of solution. The steady ventilated cavitating flows in water tunnels of different diameter were simulated for a conceptual underwater vehicle model which had a disk cavitator. It is found that the choked cavitation number derived is close to the approximate solution of natural cavitating flow for a 3-D disk. The critical ventilation rate falls with decreasing diameter of the water tunnel. However, the cavity size and drag coeflicient are rising with the decrease in tunnel diameter for the same ventilation rate, and the cavity size will be much different in water tunnels of different diameter even for the same ventilated cavitation number.

关键词： ventilated cavitation water tunnel choked cavitation number critical ventilation rate

Design method of pile-slab structure roadbed of ballastless track on soil subgrade

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Journal of Central South University 2013年第7期20卷 2072-2082页

作者： zhan yong-xiang YAO Hai-lin JIANG Guan-lu Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China State Key Laboratory of Geomechanics and Geotechnical Engineering (Institute of Rock and soil Mechanics Chinese Academy of Sciences) Wuhan 430071 China School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China

Pile-slab structure roadbed is a new form of ballastless track for high speed railway. Due to lack of corresponding design code, based on the analysis of its structure characteristics and application requirements, it is proposed to carry out load effect combination according to ultimate limit state and serviceability limit state, and the most unfavorable combination of each state is chosen to carry through design calculation for pile-slab structure. Space model of pile-slab structure can be simplified as a plane flame model, by using the orthogonal test method, and the design parameter of pile-slab structure is optimized. Moreover, based on the engineering background of Suining-Chongqing high-speed railway, the dynamic deformation characteristics of pile-slab structure roadbed are further researched by carrying on the indoor dynamic model test. The test results show that the settlement after construction of subgrade satisfies the requirement of settlement control to build ballastless track on soil subgrade for high-speed railway. Slab structure plays the role of arch shell as load is transmitted from slab to pile, and the vertical dynamic stress of subgrade soil is approximately of ＂K＂ form distribution with the depth. The distribution of pile stress is closely related to soil characteristics, which has an upset triangle shape where the large dynamic stress is at the top. Pile compared with soil shares most dynamic stress. Pile structure expands the depth of the dynamic response of subgrade has limited effect on dynamic response. These results can provide subgrade. and improves the stress of subgrade soil, and the speed of train scientific basis for pile-slab structure roadbed used on soil

关键词： soil subgrade ballastless track pile-slab structure roadbed load combination dynamic model test

Redox-responsive polymer prodrug/AgNPs hybrid nanoparticles for drug delivery

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Chinese Chemical Letters 2018年第2期29卷 301-304页

作者： Liang Qiu Linfei Zhao Chengfen Xing yong zhan Institute of Biophysics Hebei University of Technology

A drug carrier system of the hybrid nanoparticles based on the redox-responsive P[（2-（（2-（（camptothecin）-oxy）ethyl）disulfanyl）ethylmethacrylate）-co-（2-（D-galactose）methylmethacryl-ate）]（P（MACPTS-co-MAGP）） and AgNPs is developed to deliver the anti-cancer drug camptothecin（CPT） and monitor the drug release by the recovery of the fluorescence of CPT. CPT is linked to the polymer sidechains via a redox-responsive disulfide bond, attaching on the surface of AgNPs and leading to the quenching of CPT fluorescence（＂off＂ state） due to the nanoparticle surface energy transfer（NSET） *** the exposure to glutathione（GSH）, the disulfide bond is cleaved to release CPT, resulting in the recovery of the fluorescence of CPT（＂on＂ state）. The system offers a platform to track the CPT delivery and releasing in real time

关键词： Redox-responsive Drug delivery system Hybrid nanoparticles NSET effect