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On a Generalized Extended F-Expansion Method

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Communications in Theoretical Physics 2006年第1期45卷 15-28页

作者： REN Yu-Jie LIU shu-Tian ZHANG Hong-qing Department of Applied Mathematics Dalian University of Technology Dalian 116024 China Department of Mathematics and Physics Dalian Institute of Light Industry Dalian 116034 China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China

Making use of a new generalized ansatz, we present a new generalized extended F-expansion method for constructing the exact solutions of nonlinear partial differential equations in a unified way. Applying the generalized method with the aid of Maple, we consider the （2＋1）-dimentional breaking soliton equation. As a result, we successfully obtain some new and more general solutions including Jacobi elliptic function solutions, soliton-like solutions, trigonometric function solutions, and so on. As an illustrative sampler the properties of some soliton solutions for the breaking soliton equation are shown by some figures. Our method can also be applied to other partial differential equations.

关键词： (2+1)-dimentional breaking soliton equation generalized extended F-expansion method Jacobi elliptic function solution generalized ansatz soliton-like solution

Geochemistry and geochronology of Late Jurassic and Early Cretaceous intrusions related to some Au(Sb) deposits in southern Anhui: a case study and review

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Acta Geochimica 2018年第3期37卷 360-383页

作者： qing Hu Huangling Gu Xiaoyong Yang Yisu Ren Ergen Gao Zhangxing nie CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of China College of Civil Engineering Anhui Jianzhu University No.311 Geological Team Anhui Bureau of Geology and Mineral Resources Exploration

Some Au deposits in southern Anhui Province have recently been found to be closely associated with Late Mesozoic intrusions. Typical examples include the Huashan Au(Sb) deposit and Au deposits at Zhaojialing, Wuxi,and Liaojia. In order to understand the mechanisms that led the formation of these Au deposits, we make detailed reviews on the geological characteristics of these Au deposits. Specifically, we present new LA-ICP-MS zircon U–Pb dating, along with elemental and Hf isotopic data from the Huashan Au(Sb) deposit. Our data suggests that the Huashan ore-related intrusions were emplaced during the Late Jurassic and Early Cretaceous periods(144–148 Ma). They are characterized by arc-magma features and high oxygen fugacity and are rich in inherited zircons. Zircon U–Pb ages and Lu–Hf isotopes from intrusions suggest that Proterozoic juvenile lithosphere is the main source of these intrusions. The regional geological history implies that lithosphere beneath southern Anhui was produced during a Proterozoic subduction and was fertilized with Au(Cu) in the process. Integrated with theresults of previous studies, we inferred that Late Mesozoic intrusions formed by the remelting of the lithosphere could provide the metal endowment for the Au-rich deposits in southern Anhui.

关键词： Yanshannian magmatism Subduction-modified lithosphere Au (Sb) deposits Southern Anhui South China

A Note on L(2,1)-labelling of Trees

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Acta Mathematicae Applicatae Sinica 2012年第2期28卷 395-400页

作者： Ming-qing ZHAI Chang-hong LU Jin-long shu School of Mathematical Science Nanjing Normal University Jiangsu Nanjing 210046 China Department of Mathematics Chuzhou University Chuzhou 239012 China Department of Mathematics East China Normal University Shanghai 200241 China

An L（2, 1）-labelling of a graph G is a function from the vertex set V（G） to the set of all nonnegative integers such that │f（u） - f（v）│≥2 if dG（u, v） = 1 and │f（u） - f（v）│ ≥ 1 if dG（u, v） = 2. The L（2, 1）-labelling problem is to find the smallest number, denoted by A（G）, such that there exists an L（2, 1）-labelling function with no label greater than it. In this paper, we study this problem for trees. Our results improve the result of Wang [The L（2, 1）-labelling of trees, Discrete Appl. Math. 154 （2006） 598-603].

关键词： distance-two labelling L(2, 1)-labelling tree

Studies on the Rice LEAF INCLINATION1 （LC1）, an IAA-amido Synthetase, Reveal the Effects of Auxin in Leaf Inclination Control

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Molecular Plant 2013年第1期6卷 174-187页

作者： shu-qing Zhao Jing-Jing Xiang Hong-Wei Xue National Key Laboratory of Plant Molecular Genetics institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences ChineseAcademy of Sciences Shanghai 200032 China

The angle of rice leaf inclination is an important agronomic trait and closely related to the yields and archi- tecture of crops. Although few mutants with altered leaf angles have been reported, the molecular mechanism remains to be elucidated, especially whether hormones are involved in this process. Through genetic screening, a rice gain-of- function mutant leaf inclination1, Icl-D, was identified from the Shanghai T-DNA Insertion Population （SHIP）. Phenotypic analysis confirmed the exaggerated leaf angles of Icl-D due to the stimulated cell elongation at the lamina joint. LC1 is transcribed in various tissues and encodes OsGH3-1, an indole-3-acetic acid （IAA） amido synthetase, whose homolog of Arabidopsis functions in maintaining the auxin homeostasis by conjugating excess IAA to various amino acids. Indeed, recombinant LC1 can catalyze the conjugation of IAA to Ala, Asp, and Asn in vitro, which is consistent with the decreased free IAA amount in Icl-D mutant. Icl-D is insensitive to IAA and hypersensitive to exogenous BR, in agreement with the microarray analysis that reveals the altered transcriptions of genes involved in auxin signaling and BR biosynthesis. These results indicate the crucial roles of auxin homeostasis in the leaf inclination control.

关键词： rice leaf inclination auxin GH3.

Analysis on vibration characteristics of large-size rectangular piezoelectric composite plate based on quasi-periodic phononic crystal structure

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Chinese Physics B 2022年第5期31卷 438-447页

作者： Li-qing Hu Sha Wang shu-Yu Lin Shaanxi Key Laboratory of Ultrasonics Institute of Applied AcousticsShaanxi Normal UniversityXi’an 710119China

Based on the theory of composite materials and phononic crystals(PCs),a large-size rectangular piezoelectric composite plate with the quasi-periodic PC structure composed of PZT-4 and epoxy is proposed in this *** PC structure can suppress the transverse vibration of the piezoelectric composite plate so that the thickness mode is purer and the thickness vibration amplitude is more ***,the vibration of the model is analyzed theoretically,the electromechanical equivalent circuit diagram of three-dimensional coupled vibration is established,and the resonance frequency equation is *** effects of the length,width,and thickness of the piezoelectric composite plate at the resonant frequency are obtained by the analytical method and the finite element method,the effective electromechanical coupling coefficient is also *** results show that the resonant frequency can be changed regularly and the electromechanical conversion can be improved by adjusting the size of the rectangular piezoelectric *** effect of the volume fraction of the scatterer on the resonant frequency in the thickness direction is studied by the finite element *** band gap in X and Y directions of large-size rectangular piezoelectric plate with quasi-periodic PC structures are *** results show that the theoretical results are in good agreement with the simulation *** the resonance frequency is in the band gap,the decoupling phenomenon occurs,and then the vibration mode in the thickness direction is purer.

关键词： composite materials rectangular piezoelectric plate coupled vibration band gap

Entropy of Dirac Field in Non-stationary and Slowly Changing Reissner-Nordstrom Black Hole

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Communications in Theoretical Physics 2005年第5X期44卷 955-960页

作者： LI Hui-Ling YANG shu-Zheng JIANG qing-Quan Institute of Theoretical Physics China West Normal University Nanchong 637002 China

Using the thin film brick-wall model and WKB approximation, the entropy of the Dirac field in the non-stationary and slowly changing Reissner-Nordstrom (R-N) black hole is calculated. The result shows that the entropy... 详细信息

关键词： slowly changing thin brick-wall model Dirac field entropy of black hole

2D-QSAR Studies on Triazolone Compounds Containing Benzenesulfonic Amide

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Chinese Journal of Structural Chemistry 2007年第8期26卷 883-888页

作者： WEI qing-Li GAO Jun SUN Dao-Xing ZHANG shu-Sheng College of Chemistry and Molecular Engineering Qingdao University of Science ＆ Technology Qingdao 266042 China

The geometry structures of 6 triazolone compounds containing benzenesulfonic amide were fully optimized with DFT （Density Functional Theory） method at the B3LYP/6-31G level, and the structural and electronic parameters of the compounds were calculated. The hydrophobic and topological parameters of the title compounds were calculated by HyperChem software. The mono- and bi-parametric models between the parameters and biological activity of the compounds were analyzed by Multiple Linear Regression method based on Hansch-Fujita model. The results show that the activities of the title compounds were increased with higher hydrophobic property logP and molecular volume V, lower molecular energy ETOTAL and electronegative of benzene ring Qph.

关键词： benzenesulfonic amide triazolone compounds 2D-QSAR DFT method

Compression Properties and Energy Absorption of A Novel Double Curved Beam Negative Stiffness Honeycomb Structures

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China Ocean Engineering 2024年第5期38卷 821-837页

作者： ZHENG Ze-peng WANG shu-qing WANG Xi-chen YUE Wen College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China

This paper presents the design of a novel honeycomb structure with a double curved *** purpose of this design is to achieve vibration isolation for the main engine of an offshore platform and reduce impact *** analytical formula for the force-displacement relationship of the honeycomb single-cell structure is presented based on the modal superposition *** formula provides a theoretical basis for predicting the compression performance of honeycomb *** effects of structural geometric parameters,series and parallel connection methods on the mechanical and energy absorption properties are investigated through mathematical modeling and experimental ***,the study focuses on the vibration isolation and impact resistance performance of honeycomb *** results show that the designed honeycomb structure has good mechanical and energy absorption performance,and its energy absorption effect is related to the geometric parameters and series and parallel connection methods of the *** isolation efficiency of the honeycomb with 4 rows and 3 columns reaches 38%.The initial isolation frequency of the isolator is 11.7 Hz.

关键词： double curved beam compression properties energy absorption vibration isolation

Mechanism of piR-1245/PIWI-like protein-2 regulating Janus kinase-2/signal transducer and activator of transcription-3/vascular endothelial growth factor signaling pathway in retinal neovascularization

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Neural Regeneration Research 2023年第5期18卷 1132-1138页

作者： Yong Yu Li-Kun Xia Yu Di qing-Zhu nie Xiao-Long Chen Department of Ophthalmology Shengjing Hospital of China Medical UniversityShenyangLiaoning ProvinceChina

Inhibiting retinal neovascularization is the optimal strategy for the treatment of retina-related diseases, but there is currently no effective treatment for retinal neovascularization. P-element-induced wimpy testis(PIWI)-interacting RNA(piRNA) is a type of small non-coding RNA implicated in a variety of diseases. In this study, we found that the expression of piR-1245 and the interacting protein PIWIL2 were remarkably increased in human retinal endothelial cells cultured in a hypoxic environment, and cell apoptosis, migration, tube formation and proliferation were remarkably enhanced in these cells. Knocking down piR-1245 inhibited the above phenomena. After intervention by a p-JAK2 activator, piR-1245 decreased the expression of hypoxia inducible factor-1α and vascular endothelial growth factor through the JAK2/STAT3 pathway. For in vivo analysis, 7-day-old newborn mice were raised in 75 ± 2% hyperoxia for 5 days and then piR-1245 in the retina was knocked down. In these mice, the number of newly formed vessels in the retina was decreased, the expressions of inflammationrelated proteins were reduced, the number of apoptotic cells in the retina was decreased, the JAK2/STAT3 pathway was inhibited, and the expressions of hypoxia inducible factor-1α and vascular endothelial growth factor were decreased. Injection of the JAK2 inhibitor JAK2/TYK2-IN-1 into the vitreous cavity inhibited retinal neovascularization in mice and reduced expression of hypoxia inducible factor-1α and vascular endothelial growth factor. These findings suggest that piR-1245 activates the JAK2/STAT3 pathway, regulates the expression of hypoxia inducible factor-1α and vascular endothelial growth factor, and promotes retinal neovascularization. Therefore, piR-1245 may be a new therapeutic target for retinal neovascularization.

关键词： angiogenesis human retinal endothelial cells hypoxia inducible factor-1α hypoxia interleukin-1β migration non-coding RNA oxygen-induced injury PIWI-interacting RNA retinopathy