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Journal of Systems Science & Complexity 2012年第5期25卷 873-879页

作者： feng JIANG Yi shen Xiaoxin LIAO Department of Control Science and Engineering Huazhong University of Science and Technology School of Statistics and Mathematics Zhongnan University of Economics and Law Department of Control Science and Engineering the Key Laboratory of Ministry of Eduction for Image Processing and Intelligent ControlHuazhong University of Science and Technology

In the literature （Tan and Wang, 2010）, Tan and Wang investigated the convergence of the split-step backward Euler （SSBE） method for linear stochastic delay integro-differential equations （SDIDEs） and proved the mean-square stability of SSBE method under some condition. Unfortu- nately, the main result of stability derived by the condition is somewhat restrictive to be applied for practical application. This paper improves the corresponding results. The authors not only prove the mean-square stability of the numerical method but also prove the general mean-square stability of the numerical method. Furthermore, an example is given to illustrate the theory.

关键词： General mean-square stability mean-square stability split-step backward Euler method stochastic delay integro-differential equations.

Clarkson-Kruskal Direct Similarity Approach for Differential-Difference Equations

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Communications in Theoretical Physics 2005年第6X期44卷 964-966页

作者： shen Shou-feng Department of Mathematics Zhejiang University of Technology Hangzhou 310014 China

In this letter, the Clarkson-Kruskal direct method is extended to similarity reduce some differentialdifference equations. As examples, the differential-difference KZ equation and KP equation are considered.

关键词： differential-difference KZ equation differential-difference KP equation direct method similarity reduction

Multi-linear Variable Separation Approach to Solve a （1＋1）-Dimensional Coupled Integrable Dispersionless System

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Communications in Theoretical Physics 2005年第5X期44卷 779-782页

作者： shen Shou-feng Department of Mathematics Zhejiang University of Technology Hangzhou 310014 China

The multi-linear variable separation approach (MLVSA ) is very useful to solve (2+ 1)-dimensional integrable systems. In this letter, we extend this method to solve a (1+1)-dimensional coupled integrable dispersion-less ***, by using a Backlund transformation and the MLVSA, we find a new general solution and define a new "universal formula". Then, some new (1+1)-dimensional coherent structures of this universal formula can be found by selecting corresponding functions appropriately. Specially, in some conditions, bell soliton and kink soliton can transform each other, which are illustrated graphically.

关键词： variable separation approach (1+1)-dimensional coupled integrable dispersion-less system co-erent structure

Rotation Periods of Nine ROSAT Selected Solar-Type Stars

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Chinese Journal of Astronomy and Astrophysics 2007年第4期7卷 551-557页

作者： Li-feng Xing Shuang-Yi Zhao wei Su Yan shen Xiao-Bin Zhang Jian-Yan wei Department of Technology and Physics Zhengzhou Unversity of Light Industry Zhengzhou 450002 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 Department of Physics Xingtai University Xingtai 054001

We monitored 16 X-ray selected young solar-type stars for light variation and found appreciable periodic light variability with amplitudes of a few hundredths of a magni- tude in nine of the objects. Using the method of Phase Dispersion Minimization （PDM） and Fourier analysis （software PERIOD04）, the rotation periods of these stars were determined from the photometric data. The rotation periods of all nine stars are shorter than about 3 days. It is suggested that, as with the Pleiades cluster, small amplitude light variations are quite common among young solar-type stars with rotation periods around 3 days or less. This gives further evidence for the spin up of solar-type stars predicted by models of angular momentum evolution of pre-main sequence stars.

关键词： stars: late-type - stars: pre-main sequence - stars: rotation

Inhibition of hepatitis B virus gene expression and replication by artificial microRNA

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World Journal of Gastroenterology 2008年第29期14卷 4684-4689页

作者： Yu-feng Gao Li Yu wei wei Jia-Bin Li Qing-Li Luo Ji-Long shen Institute of Clinical Pharmacology Anhui Medical University Hefei 230032 Anhui Province China Anhui Key Laboratory ofZoonoses Hefei 230032 Anhui Province China The Key Laboratory of Gene Resource Utilization for Severe Diseases The Ministry of Education of China and Anhui Province Hefei 230032 Anhui Province China Department of Infectious Diseases The First Affiliated Hospital of Anhui Medical University Hcfci 230032 Anhui Province China

AIM: To investigate the inhibitory effects of hepatitis B virus (HBV) replication and expression by transfecting artificial microRNA (amiRNA) into HepG2.2.15 cells. METHODS: Three amiRNA-HBV plasmids were constructed and transfected into HepG2.2.15 cells. HBV antigen secretion was detected in the cells with transient and stable transfection by time-resolved fluoroimmunoassays (TRFIA). HBV DNA replication was examined by ? uorescence quantitative PCR, and the level of HBV S mRNA was measured by semi- quantitative RT-PCR. RESULTS: The efficiency of transient transfection of the vectors into 2.2.15 cells was 55%-60%. All the vectors had significant inhibition effects on HBsAg and HBeAg at 72 h and 96 h after transfection (P < 0.01 for all). The secretion of HBsAg and HBeAg into the supernatant was inhibited by 49.8% ± 4.7% and 39.9% ± 6.7%, respectively, at 72 h in amiRNA- HBV-S608 plasmid transfection group. The copy of HBV DNA within culture supernatant was also significantly decreased at 72 h and 96 h after transfection (P <0.01 for all). In the cells with stable transfection, the secretion of HBsAg and HBeAg into the supernatant was significantly inhibited in all three transfection groups (P < 0.01 for all, vs negative control). The copies of HBV DNA were inhibited by 33.4% ± 3.0%, 60.8% ± 2.3% and 70.1% ± 3.3%, respectively. CONCLUSION: In HepG2.2.15 cells, HBV replication and expression could be inhibited by artif icial microRNA targeting the HBV S coding region. Vector-based artificial microRNA could be a promising therapeutic approach for chronic HBV infection.

关键词： Hepatitis B virus RNA interference Artificial microRNA HepG2.2.15 cell

Highlights of mainstream solar cell efficiencies in 2023

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Frontiers in Energy 2024年第1期18卷 8-15页

作者： Wenzhong shen Yixin ZHAO feng LIU Institute of Solar Energy and Key Laboratory of Artificial Structures and Quantum Control(Ministry of Education)School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China School of Environmental Science and Engineering and Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240China School of Chemistry and Chemical Engineering and Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240China

This article continues our highlights last two years[1,2]on the highest independently confirmed mainstream(silicon,perovskite,and organic)solar cell efficiencies in *** world record power conversion efficiency(PCE)of the single-junction silicon and perovskite/silicon tandem solar cells has reached over 27%and close to 34%,respectively,in *** have also witnessed the rapid mass-production development of the silicon passivating contact and silicon back contact solar cells,as well as further progress with perovskite solar cells(PSCs).

关键词： perovskite mainstream fir

Dynamics and Mechanism of A Quorum Sensing Network Regulated by Small RNAs in Vibrio Harveyi

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Communications in Theoretical Physics 2011年第3期55卷 465-472页

作者： shen Jian-wei Institute of Applied Mathematics Xuchang University Xuchang 464000 China Institute of System Biology Shanghai University Shanghai 200444 China

Bacterial quorum sensing （QS） has attracted much interests and it is an important process of cell communication. Recently, Bassler et al. studied the phenomena of QS regulated by small RNAs and the experimental data showed that smafl RNAs played important role in the QS of Vibrio harveyi and it can permit the fine-tuning of gene regulation and mmntenance of homeostasis. According to Michaelis-Menten kinetics and mass action law in this paper, we construct a mathematical model to investigate the mechanism induced QS by coexist of small RNA and signal molecular （AI） and show that there are periodic oscillation when the time delay and Hill coefficient exceed a critical value and the periodic oscillation produces the change of concentration and induces QS. These results are fit to the experimental results. In the meanwhile, we also get some theoretical value of Hopf Bifurcation on time deday. In addition, we also find this network is robust against noise.

关键词： quorum sensing genetic network oscillation small RNA bifurcation negative feedback loop

景观格局对生态系统服务空间分异特征的影响——以东营市为例

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东北林业大学学报 2025年第2期53卷 86-96页

作者：房子钰丁宁冯恒栋沈阳张达延边大学吉林省·珲春市133300

以山东省东营市全域为研究区域,以2000、2010、2020年,来源于地理空间数据云(https://***/)的Landsat遥感影像数据、资源环境科学数据平台(https://***/)的中国多时期土地利用遥感监测数据集(CNLUCC)、《东营市统计年鉴》的东营市社会... 详细信息

以山东省东营市全域为研究区域,以2000、2010、2020年,来源于地理空间数据云(https://***/)的Landsat遥感影像数据、资源环境科学数据平台(https://***/)的中国多时期土地利用遥感监测数据集(CNLUCC)、《东营市统计年鉴》的东营市社会经济统计数据为数据源;应用ENVI 5.3软件对卫星影像数据进行预处理,将预处理后的数据采用ArcGIS 10.2软件进行目视评价分类,根据东营市实际情况将土地利用和土地覆盖类型划分为农田、湿地、水体、建设用地、草地共5类;综合考虑景观的面积度量、形状选择、多样性程度、离散程度4个方面,设计斑块密度、最大斑块指数、景观形状指数、分离度指数、香农多样性指数、散布与并列指数6个景观指标,评价东营市的景观格局特征;以生态系统服务价值为评价指标、景观格局特征(景观格局指数)为影响因素,采用价值转移法依据修正的价值当量系数计算东营市生态系统服务价值,利用普通最小二乘法(OLS)模型、地理加权回归模型(GWR)分析东营市景观格局对生态系统服务价值空间分异特征的影响。结果表明:①2000—2020年,东营市农田、建设用地、水体面积增加,湿地、草地面积减少。②2000—2020年,东营市整体景观特征的指数变化,最大斑块指数、景观形状指数增加,而斑块密度、分离度指数、散布与并列指数、香农多样性指数减少,斑块类型特征指数变化各异。③2000—2020年,东营市生态系统服务价值总体增加了约1.95亿元,空间上生态系统服务价值呈现北部和东部高、西部和南部低的特点。④2000—2020年,斑块密度对生态系统服务价值总体为负向影响、散布与并列指数对生态系统服务价值仅具有正向影响(影响系数范围为0.04~0.45)、分离度指数和香农多样性指数都对生态系统服务价值整体具有正向影响。

关键词：景观格局生态系统服务价值空间分异特征东营市

A Numerical Investigation of the Stress Relief Zones Around a Longwall Face in the Lower Seam for Gas Drainage Considerations

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Computer Modeling in Engineering & Sciences 2021年第4期127卷 135-157页

作者： Chunlei Zhang YPChugh Ruimin feng Yong Zhang wei shen Jingke Wu Yushun Yang Faculty of Architecture and Civil Engineering Huaiyin Institute of TechnologyHuai’an223001China Mining and Mineral Resources Engineering Southern Illinois UniversityCarbondaleIllinois62901USA School of Mechanics and Civil Engineering China University of Mining&Technology(Beijing)Beijing100083China Department of Civil Engineering University of ArkansasFayettevilleAR 72701USA School of Energy and Mining Engineering China University of Mining&Technology(Beijing)Beijing100083China

Extraction of a protective coal seam (PVCS)-below or above a coal seam to be mined with the potential of coal andgas outburst risk-plays an important role not only in decreasing the stress field in the surrounding rock mass but alsoin increasing the gas desorption capacity and gas flow permeability in the protected coal seam (PTCS). The PVCSis mined to guarantee the safe mining of the PTCS. This study has numerically evaluated the stress redistributioneffects using FLAC3D model for a longwall face in Shanxi Province. The effects of mining depth, mining height andinter-burden rock mass properties were evaluated using the stress relief angle and stress relief coefficient. Verticalstress distribution, stress relief angle and stress relief coefficient in the PTCS were analyzed as the face advancedin the PVCS. The results showed that the stress relief achieved in different locations of the PTCS varied as the faceadvanced. Sensitivity analyses on the pertinent variables indicate that the stress relief in the PTCS is affected mostby the mining depth followed by the inter-burden lithology and the mining height. Furthermore, the elastic moduliof different layers within the inter-burden rock mass are more important than their uniaxial compressive strength(UCS) and Poisson’s ratio. These observations can guide gas drainage borehole design to minimize the accidentsof coal and gas outbursts.

关键词： Methane drainage longwall mining protective/protected coal seam multiple seams FLAC3D software stress relief zones

Tetrahydrosalen backboned gadolinium complex as initiator for the ring-opening polymerization of ε-caprolactone

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Chinese Chemical Letters 2008年第6期19卷 681-684页

作者： Guang Ming Wu Xu feng Ni wei Lin Sun Zhi Quan shen Key Laboratory of Maeromoleeule Synthesis and Functionalization Ministry of Education Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

Tetrahydrosalen ligand was employed in the synthesis of gadolinium complex. The ligand was deprotoned by LiBu, and the afforded lithium salt was reacted with anhydrous GdCl3 to produce the gadolinium complex through salt metathesis. This complex was successfully used to initiate the ring-opening polymerization of ε-caprolactone. The initiation conditions in different temperature, monomer-to-initiator ratio and time were investigated. Under the condition： [ε-caprolactone]：[catalyst] = 600, 56 ℃, toluene： 2 ml, poly（ε-caprolactone）（PCL） with Mw = 11,2782 and PDI = 1.96 was achieved.

关键词： Tetrahydrosalen complex Rare earth catalyst ε-Caprolactone Ring-opening polymerization