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Journal of Computational Mathematics 2015年第4期33卷 356-378页

作者： Kai liu xinyuan Wu Department of Mathematics Nanjing University and State Key Laboratory for Novel Software Technology at Nanjing University Nanjing 210093 P.R. China

The multi-frequency and multi-dimensional adapted Runge-Kutta^NystrSm （ARKN） integrators, and multi-frequency and multi-dimensional extended Runge-Kutta-NystrSm （ERKN） integrators have been developed to efficiently solve multi-frequency oscillatory Hamiltonian systems. The aim of this paper is to analyze and derive high-order sym- plectic and symmetric composition methods based on the ARKN integrators and ERKN integrators. We first consider the symplecticity conditions for the multi-frequency and multi-dimensional ARKN integrators. We then analyze the symplecticity of the adjoint in- tegrators of the multi-frequency and multi^dimensional symplectic ARKN integrators and ERKN integrators, respectively. On the basis of the theoretical analysis and by using the idea of composition methods, we derive and propose four new high-order symplectic and symmetric methods for the multi-frequency oscillatory Hamiltonian systems. The numer- ical results accompanied in this paper quantitatively show the advantage and efficiency of the proposed high-order symplectic and symmetric methods.

关键词： Symplectic and symmetric composition methods Multi-frequency and multi-dimensional ERKN integrators ARKN integrators Multi-frequency oscillatory Hamiltonian systems.

Analysis of the Structure of Different Tibetan Plateau Vortex Types

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Journal of Meteorological Research 2017年第3期31卷 514-529页

作者： xinyuan FENG Changhai liu Guangzhou FAN Jie ZHANG College of Atmospheric Sciences Chengdu University of Information Technology/Plateau Atmosphere and Environment Key Laboratory of Sichuan Province National Center for Atmospheric Research Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology

Knowledge of the structure of the Tibetan Plateau vortex （TPV） is of considerable importance for understanding the generation and development mechanisms of this mesoscale system. However, our understanding of vortex struc- tures and our ability to classify them on a physical basis is limited due to insufficient observations. The high- resolution new-generation NCEP-CFSR （Climate Forecast System Reanalysis） dataset is used in the present paper to investigate the general structural features of various types of mature TPV through classification and composite struc- ture analysis. Results indicate that the dynamic and thermodynamic structures show regional and seasonal depend- ency, as well as being influenced by attributes of translation, associated precipitation, and the South Asian high （SAH）. The common precipitating TPV （type I）, frequently occurring in the west-east-oriented zonal region between 33° and 36°N, is a notably low-level baroclinic and asymmetric system. It resides within a large-scale confluent zone and preferentially travels eastward, potentially moving out of the plateau. The heavy rain vortex （type II） corresponds to a deep vortex circulation occurring in midsummer. The low-level baroclinic sub-category （type IIa） is associated with a low-level jet and mainly originates in the area 32°-35°N, 86°-94°E, preferentially moving east of 90°E and even away from the plateau; meanwhile, the nearly upright sub-category （type IIb）, which has a cold center at low levels and a warm center at mid-upper levels, is a quasi-stationary and quasi-symmetric system favorably occurring west of 92°E. A western-pattern SAH exists in the upper troposphere for these two sub-categories. The springtime dry vortex in the western plateau （type III） is warm and shallow （approximately 100 hPa deep）, and zonal circulation dominates the large-scale environmental flows in the middle and upper troposphere. The precipitating vortex in the southern plateau occurring during July-August

关键词： Tibetan Plateau vortex vortex structure composite analysis physical classification Climate ForecastSystem Reanalysis

Optimized scheduling of integrated energy systems for low carbon economy considering carbon transaction costs

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Global Energy Interconnection 2024年第4期7卷 377-390页

作者： Chao liu Weiru Wang Jing Li xinyuan liu Yongning Chi China Electric Power Research Institute Beijing 100192P.R.China State Grid Shanxi Electric Power Research Institute Taiyuan 030001P.R.China

With the introduction of the“dual carbon”goal and the continuous promotion of low-carbon development,the integrated energy system(IES)has gradually become an effective way to save energy and reduce *** study proposes a low-carbon economic optimization scheduling model for an IES that considers carbon trading *** the goal of minimizing the total operating cost of the IES and considering the transferable and curtailable characteristics of the electric and thermal flexible loads,an optimal scheduling model of the IES that considers the cost of carbon trading and flexible loads on the user side was *** role of flexible loads in improving the economy of an energy system was investigated using examples,and the rationality and effectiveness of the study were verified through a comparative analysis of different *** results showed that the total cost of the system in different scenarios was reduced by 18.04%,9.1%,3.35%,and 7.03%,respectively,whereas the total carbon emissions of the system were reduced by 65.28%,20.63%,3.85%,and 18.03%,respectively,when the carbon trading cost and demand-side flexible electric and thermal load responses were considered *** electrical and thermal loads did not have the same impact on the system *** the analyzed case,the total cost and carbon emissions of the system when only the flexible electrical load response was considered were lower than those when only the flexible thermal load response was taken into *** have an excess of carbon trading credits and can profit from selling them,whereas other devices have an excess of carbon trading and need to buy carbon credits.

关键词： Demand response Combined cooling Heating and power system Carbon transaction costs Flexible electric and thermal loads Optimal scheduling

A wide-field and high-resolution lensless compound eye microsystem for real-time target motion perception

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Microsystems & Nanoengineering 2022年第4期8卷 199-207页

作者： Li Zhang Haiyang Zhan xinyuan liu Fei Xing Zheng You Department of Precision Instrument Tsinghua UniversityBeijing 100084China State Key Laboratory of Precision Measurement Technology and Instrument Tsinghua UniversityBeijing 100084China Beijing Advanced Innovation Center for Integrated Circuits Beijing 100084China

Optical measurement systems suffer from a fundamental tradeoff between the field of view(FOV),the resolution and the update rate.A compound eye has the advantages of a wide FOV,high update rate and high sensitivity to motion,providing inspiration for breaking through the constraint and realizing high-performance optical ***,most existing studies on artificial compound eyes are limited by complex structure and low resolution,and they focus on imaging instead of precise ***,a high-performance lensless compound eye microsystem is developed to realize target motion perception through precise and fast orientation *** microsystem splices multiple sub-FOVs formed by long-focal subeyes,images targets distributed in a panoramic range into a single multiplexing image sensor,and codes the subeye aperture array for distinguishing the targets from different sub-FOVs.A wide-field and high resolution are simultaneously realized in a simple and easy-to-manufacture microelectromechanical system(MEMS)aperture ***,based on the electronic rolling shutter technique of the image sensor,a hyperframe update rate is achieved by the precise measurement of multiple time-shifted spots of one *** microsystem achieves an orientation measurement accuracy of 0.0023°(3σ)in the x direction and 0.0028°(3σ)in the y direction in a cone FOV of 120°with an update rate~20 times higher than the frame *** study provides a promising approach for achieving optical measurements with comprehensive high performance and may have great significance in various applications,such as vision-controlled directional navigation and high-dynamic target tracking,formation and obstacle avoidance of unmanned aerial vehicles.

关键词： precise resolution compound

A novel strategy for cancer gene therapy:RNAi

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Chinese Science Bulletin 2006年第10期51卷 1145-1151页

作者： PAN Qiuwei CAI Rong liu xinyuan QIANCheng Xin Yuan Institute of Medicine and Biotechnology Life Science College Zhejiang Sci-Tech University Hangzhou 310018 China Institute of Biochemistry and Cell Biology Shanghai Institutes forBiological Sciences Chinese Academy of Sciences Shanghai 200031China Division of Gene Therapy and Hepatology CIMA University of Navarra Pamplona 31008 Spain

RNA 干扰(RNA ) 由两倍搁浅的 RNA 在 posttranscriptionmediated 的水平导致基因 silencing。为小 double-strandedinterference RNA (siRNA ) 的交货有众多的方法到目标房间，包括非病毒、病毒的向量。在这些方法之中，病毒的向量是... 详细信息

RNA 干扰(RNA ) 由两倍搁浅的 RNA 在 posttranscriptionmediated 的水平导致基因 silencing。为小 double-strandedinterference RNA (siRNA ) 的交货有众多的方法到目标房间，包括非病毒、病毒的向量。在这些方法之中，病毒的向量是更有效的车辆。由在目标房间的病毒的向量的短发卡 RNA (shRNA ) 的表示能被 Dicer 酶切成为约 21 bp siRNA，它能指导血缘的 mRNA 的降级。RNAi 技术能用许多策略对癌症被指导，包括抑制，支持 apoptosis，调整房间周期在上表示了 oncogenes， antiangiogenesis 并且提高化疗和放射疗法的功效。因为 RNAi 技术为癌症基因治疗成为了优秀策略，这评论构画出如此的一种新奇技术的最近的开发和应用程序。

关键词： RNAi RNA干涉肿瘤基因疗法

Construction of a Bronsted-Lewis solid acid catalyst La-PW-SiO_(2)/SWCNTs based on electron withdrawing effect of La(Ⅲ)onπbond of SWCNTs for biodiesel synthesis from esterification of oleic acid and methanol

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Chinese Journal of Chemical Engineering 2022年第4期35卷 351-362页

作者： Qing Shu xinyuan liu Yanting Huo Yuhui Tan Caixia Zhang Laixi Zou School of Chemical and Chemical Engineering Jiangxi University of Science and TechnologyGanzhou 341000China

A novel solid Bronsted-Lewis acid catalyst La-PW-SiO_(2)/SWCNTs(single-wall carbon nanotubes)was synthesized from the synergistic modification of H_(3)PW_(12)O_(40)(HPW)by single-walled carbon nanotubes functionalized with sidewall hydroxyl groups(SWCNTs–OH)and La^(3+) via sol–gel *** freshly prepared catalyst was characterized by several methods,and the catalytic activity and stability of it were studied from the esterification of oleic acid and *** showed that the highest conversion of oleic acid was 93.1%(mass)and maintained as high as 88.7%(mass)after six cycles of La-PW-SiO_(2)/*** high catalytic activity and stability of La-PW-SiO_(2)/SWCNTs can be attributed to the strong electron withdrawing effect of La^(3+) on π bond of SWCNTs,because it can facilitate the formation of a large number of strong Lewis acid ***,the reduction of catalytic activity of a solid acid catalyst due to the fact that hydration reaction of its Bronsted acid sites can be effectively ***-PW-SiO_(2)/SWCNTs can be an efficient and economical catalyst,because it shows good catalytic activity and stability.

关键词： Single-wall carbon nanotubes(SWCNTs) H_(3)PW_(12)O_(40) La^(3+) Solid Bronsted-Lewis acid catalyst Biodiesel Esterification

Assessment of heavy metal accumulation in freshwater fish of Dongting Lake,China:Effects of feeding habits,habitat preferences and body size

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Journal of Environmental Sciences 2022年第2期34卷 355-365页

作者： Xiaoming Jiang Jun Wang Baozhu Pan Dianbao Li Yuzhu Wang xinyuan liu State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China Xi'an University of TechnologyXi'an 710048China

We measured the concentrations of Cr,Fe,Ni,Cu,Zn,Cd,Pb and Hg,and the stable isotope ratios(δ^(13)C and δ^(15)N)in 87 fish samples within 12 economic fish species collected from the Dongting Lake,the second largest freshwater lake in *** few exceptions in concentration of Cr,most of fish species showed lower concentrations of the 8 metals than legislation *** fishes had significantly higher values of δ^(15)N(possessing higher trophic level)and metal concentrations than planktivorous and herbivorous ***,demersal fishes showed higher concentrations of Cu,Zn,Cd and Pb than pelagic and benthopelagic *** found positive correlations between concentrations of Fe,Pb and Hg and δ^(15)N ratio,confirming the biomagnification of the three metals through trophic *** contrast,fishes showed clear growth dilution effect for Ni,Zn,Cu,Pb and Hg,indicated by the negative correlations between their concentrations and fish weight or *** regression analysis demonstrated that growth dilution and biomagnification effects simultaneously governed the metal concentrations in fish muscle,and the two effects'importance varied among different *** human health risk assessment indicated that all 8 metals gave target hazard quotient(THQ)values<1.0,i.e.,the estimated daily intake(EDI)of metals did not exceed the oral reference dose(Rf D),indicating a safe consumption of these fish species for *** study provides comprehensive approaches to better understand the determining processes and potential risk of heavy metals in freshwater lake fishes.

关键词： Heavy metals Stable isotope ratio Biomagnification Growth dilution Risk assessment Edible fishes

A novel strategy for cancer treatment:Targeting cancer stem cells

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Chinese Science Bulletin 2008年第12期53卷 1777-1783页

作者： liu Jia MA LeiNa WANG YiGang liu xinyuan QIAN QiJun Xin Yuan Institute of Medicine and Biotechnology College of Life Science Zhejiang Sci-Tech University Hangzhou 310018 China Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China Laboratory of Viral and Gene Therapy Eastern Hepatobiliary Surgical Hospital Shanghai 200438 China

Cancer stem cell/tumor-initiating cell (CSC/TIC) is a subclass of cancer cells possessing parts of properties of normal stem cell. It has a high capacity of proliferation and plays a pivotal role in tumor recurrence and tumor resistance to radiotherapy and chemotherapy. At present, small molecule in-hibitors and fusion proteins are widely used in the CSC-targeting strategy. Gene-virotherapy, which uses oncolytic adenovirus as a vector to mediate the expression of therapeutic gene, shows a signifi-cant superiority to other regimens of cancer treatment and has a good efficacy in the treatment of solid tumors. Thus, it is a promising choice to apply gene-virotherapy into the CSC-targeting treatment. Based on the molecular mechanism underlying CSC self-renewal, a series of effective strategies for targeting CSC have been established. This review will summarize the recent research progresses on CSC-targeting treatment.

关键词：肿瘤治疗方法干细胞临床分析

Increasing prevalence of antibiotic resistance genes in manured agricultural soils in northern China

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Frontiers of Environmental Science & Engineering 2020年第1期14卷 43-54页

作者： Nan Wu Weiyu Zhang Shiyu Xie Ming Zeng Haixue liu Jinghui Yang xinyuan liu Fan Yang College of Engineering and Technology Tianjin Agricultural UniversityTianjin 300384China College of Marine and Environmental Sciences Tianjin University of Science&TechnologyTianjin 300457China Laboratory of Agricultural Analysis Tianjin Agricultural UniversityTianjin 300384China College of Horticulture and Landscape Tianjin Agricultural UniversityTianjin 300384China

Land application of manure tends to result in the dissemination of antibiotic resistance in the *** this study,the influence of long-term manure application on the enrichment of antibiotic resistance genes(ARGs)and mobile genetic elements(MGEs)in agricultural soils was *** the analyzed eight ARGs(tetA,tetW,tetX,sull,sulll,ermF,aac(6')-Ib-cr and blaTEM)and two MGEs(intJJ and Tn916/1545)were detected in both the manured and control soils,with relative abundances ranging from 10^-6 to 10^-2 Compared with the control soil,the relative abundances of ARGs and MGEs in manured soils were enriched 1.0-18.1 fold and 0.6-69.1 fold,***-throughput sequencing analysis suggested that at the phylum level,the bacteria carrying intll and ermF might be mainly affiliated with Proteobacteria and Bacteroides,*** dominant genera carrying intll and ermF cow\d be Pseudomonas and Bacteroides,independent of manure *** analysis revealed that ARGs had strong links with soil physicochemical properties(TC,TN,and OM),heavy metals(Cu,Zn and Pb)and MGEs,indicating that the profile and spread of ARGs might be driven by the combined impacts of multiple *** contrast,soil pH and C/N exhibited no significant relationships with *** findings provide evidence that long-term manure application could enhance the prevalence and stimulate the propagation of antibiotic resistance in agricultural soils.

关键词： Antibiotic resistance Mobile genetic elements Soil Manure Heavy metals

Signal for IL-2 internalization located in the endocellular domain of IL-2R γsubunit only

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Chinese Science Bulletin 1998年第16期43卷 1390-1394页

作者： Jun Lu Hongbin Ji Zhongcheng Zheng xinyuan liu Shanghai Institute of Biochemistry Chinese Academy of Sciences Shanghai China

Interleukin-2(IL-2) is an important immunoregulatory factor. After the interaction between IL-2 and its receptor, intracellular signal molecules were activated and pro-oncogenes, e.g. c-Myc, c-Fos, c-Jun and Bcl-2 were induced, then cells stimulated with IL-2 would proliferate or differentiate. During these processes, IL-2 were internalized. The internalization of IL-2 mediated by IL-2R decreases the number of IL-2R on cell membranes, and makes extracellular IL-2 enter cells and degrade. It will down-regulate IL-2 biological activities. In order to identify the IL-2R subunit responsible for IL-2 internalization, chimeric IL-2Rs which consisted of different endocellular domains and extracellular domains from various IL-2R subunits were constructed. After they were transfected into L929 cell line, the IL-2 internalization was detected. Results showed that intracellular domains from IL-2R α and β subunits could not mediate IL-2 internalization alone; the signal for IL-2 internalization was located only in the endocellular domain of IL-2R γ subunit. Furthermore, IL-2 internalization extent would be affected by affinity between IL-2 and IL-2R.

关键词： interleukin-2(IL-2) chimeric receptor internalization.