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Ginzburg-Landau Vortex and Mean Curvature Flow with External Force Field

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Acta Mathematica Sinica,English Series 2006年第6期22卷 1831-1842页

作者： huai yu jian Yan Nan LIU Department of Mathematical Sciences Tsinghua University Beijing 100084 P. R. China

This paper is devoted to the study of the vortex dynamics of the Cauchy problem for a parabolic Ginzburg Landau system which simulates inhomogeneous type II superconducting materials and three-dimensional superconducting thin films having variable thickness. We will prove that the vortex of the problem is moved by a codimension k mean curvature flow with external force field. Besides, we will show that the mean curvature flow depends strongly on the external force, having completely different phenomena from the usual mean curvature flow.

关键词： system of parabolic equations Ginzburg-Landau vortex mean curvature flow

Spacelike Hypersurfaces of Prescribed Gauss-Kronecker Curvature in Exterior Domains

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Acta Mathematica Sinica,English Series 2009年第3期25卷 491-502页

作者： Yong HUANGWuhan huai yu jian Ning SU Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 P. R. China Department of Mathematical Sciences Tsinghua University Beijing 100084 P. R. China nsu@math tsinghua edu. cn

In this paper, we prove an existence theorem for spacelike convex hypersurfaces of prescribed Gauss curvature in Minkowski space.

关键词： Gauss-Kronecker curvature Minkowski space Monge-Ampere type equation

Evolution of hypersurfaces by the mean curvature minus an external force field

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Science China Mathematics 2007年第2期50卷 231-239页

作者： Yan-nan LIU huai-yu jian Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

In this paper, we study the evolution of hypersurface moving by the mean curvature minus an external force field. It is shown that the flow will blow up in a finite time if the mean curvature of the initial surface is larger than some constant depending on the boundness of derivatives of the external force field. For a linear force, we prove that the convexity of the hypersurface is preserved during the evolution and the flow has a unique smooth solution in any finite time and expands to infinity as the time tends to infinity if the initial curvature is smaller than the slope of the force.

关键词： parabolic equation mean curvature flow maximum principle (for tensor) 35K45 53A05

Shoot Apex Demand Determines Assimilate and Nutrients Partitioning and Nutrient-uptake Rate in Tobacco Plants

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Journal of Integrative Plant Biology 2007年第11期49卷 1654-1661页

作者： huai-yu Yang Chun-jian Li Fu-Suo Zhang The Key Laboratory of Plant Nutrition Ministry of Agriculture Key Laboratory of Plant-Soil Interactions Ministry of Education Department of Plant Nutrition China Agricultural University Beijing 100094 China

Our previous experiment revealed that apex-removed plants have larger root systems but a lower K＋-uptake rates than intact tobacco plants. Since the apex is not only a center of growth and metabolism, but also an important place of auxin synthesis and export, the aims of this study were to distinguish whether the apex demand or auxin synthesized in the apex regulates assimilate and nutrients partitioning within plant, and to explain the reason for the lower K＋-uptake rate of the apex-removed plant. In comparison with the control plant, covering the shoot apex with a black transparent plastic bag reduced net increases in dry matter and nutrients; however, the distribution of the dry matter and nutrients between shoot and roots and nutrient-uptake rates were not changed. Removal of the shoot apex shifted the dry mass and nutrients distributions to roots, and reduced the rate of nutrient uptake. Application of 1-naphthylacetic acid （NAA） could partly replace the role of the removed apex, stimulated assimilate and nutrient deposition into the treated tissue, and enhanced the reduced plasma membrane ATPase activity of roots to the control level. However, treatment of the apex-removed plants with NAA could not rescue the reduced nutrient uptake rate and the shifted assimilates and nutrients partitioning caused by excision of the apex. Higher nutrient uptake rate of the intact plants could not be explained by root growth parameters, such as total root surface area and number of root tips. The results from the present study indicate that strong apex demand determined assimilates and nutrients partitioning and nutrient-uptake rate in tobacco （Nicotiana tabacum） plants.

关键词： assimilate and nutrient partitioning auxin nutrient uptake removal of the shoot apex shoot apex demand tobacco (Nicotiana tabacum).

Ideal Bi-Based Hybrid Anode Material for Ultrafast Charging of Sodium-Ion Batteries at Extremely Low Temperatures

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NANO-MICRO LETTERS 2025年第1期17卷 1-16页

作者： Bai, Jie Jia, jian Hui Wang, yu Yang, Chun Cheng jiang, Qing Jilin Univ Key Lab Automobile Mat Sch Mat Sci & Engn Minist Educ Changchun 130022 Peoples R China

Metallic nanoparticles with excellent size controllability and high loading rate are obtained via ultrafast high temperature shock *** Bi/CNRs-15 electrode exhibits an unprecedented rate performance (237.9 mAh g-1 at 2 A g-1) at - 60 degrees C, while the energy density of the full cell can reach to 181.9 Wh kg-1 at - 40 degrees C.A novel strategy of high-rate activation is proposed to obtain high capacity and superior stability at low temperature by creating new active sites for interfacial reaction. Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at - 20 degrees C or lower. However, the key capability of ultrafast charging at ultralow temperature for SIBs is rarely reported. Herein, a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue, which is synthesized via a high temperature shock method. Such a hybrid shows an unprecedented rate performance (237.9 mAh g-1 at 2 A g-1) at - 60 degrees C, outperforming all reported SIB anode materials. Coupled with a Na3V2(PO4)3 cathode, the energy density of the full cell can reach to 181.9 Wh kg-1 at - 40 degrees C. Based on this work, a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activation Ultrafast charging Low-temperature sodium-ion batteries

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基于OSG林地可视化系统设计与实现

系统仿真学报 2008年第S1期20卷 352-354,358页

作者：黄友良淮永建于鹏艾毅北京林业大学信息学院北京100083

森林、树木和花卉等植被实时可视化仿真是复杂虚拟园林环境中的重要组成部分。论文基于OpenSceneGraph(OSG)和实时建模工具MultiGen Creator(Creator)设计并实现了林分场景可视化系统。重点介绍了系统实现的框架和技术流程,并对如何在Cr... 详细信息

森林、树木和花卉等植被实时可视化仿真是复杂虚拟园林环境中的重要组成部分。论文基于OpenSceneGraph(OSG)和实时建模工具MultiGen Creator(Creator)设计并实现了林分场景可视化系统。重点介绍了系统实现的框架和技术流程,并对如何在Creator中建立模型的层次结构关系进行了分析与研究。同时对该系统中使用的关键技术,如粒子系统、漫游设计和碰撞检测等实现方法进行了介绍。最后利用该方法对北京市八达岭地区林分场景进行了可视化模拟,模拟的场景逼真、自然,能满足用户实时交互的需要。

关键词：虚拟环境林区仿真 OpenSceneGraph MultiGen Creator

Perilipin-2 mediates ferroptosis in oligodendrocyte progenitor cells and myelin injury after ischemic stroke

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Neural Regeneration Research 2025年第7期20卷 2015-2028页

作者： jian Yang jiang Wu Xueshun Xie Pengfei Xia Jinxin Lu Jiale Liu Lei Bai Xiang Li Zhengquan yu Haiying Li Department of Neurosurgery&Brain and Nerve Research Laboratory The First Affiliated Hospital of Soochow UniversitySuzhouJiangsu ProvinceChina Institute of Stroke Research Soochow UniversitySuzhouJiangsu ProvinceChina

Differentiation of oligodendrocyte progenitor cells into mature myelin-forming oligodendrocytes contributes to *** of remyelination due to oligodendrocyte progenitor cell death can result in severe nerve *** is an iron-dependent form of regulated cell death caused by membrane rupture induced by lipid peroxidation,and plays an important role in the pathological process of ischemic ***,there are few studies on oligodendrocyte progenitor cell *** analyzed transcriptome sequencing data from GEO databases and identified a role of ferroptosis in oligodendrocyte progenitor cell death and myelin injury after cerebral *** analysis suggested that perilipin-2(PLIN2)was involved in oligodendrocyte progenitor cell ***2 is a lipid storage protein and a marker of hypoxia-sensitive lipid droplet *** further investigation,we established a mouse model of cerebral ischemia/*** found significant myelin damage after cerebral ischemia,as well as oligodendrocyte progenitor cell death and increased lipid peroxidation levels around the infarct *** ferroptosis inhibitor,ferrostatin-1,rescued oligodendrocyte progenitor cell death and subsequent myelin *** also found increased PLIN2 levels in the peri-infarct area that co-localized with oligodendrocyte progenitor ***2 knockdown rescued demyelination and improved neurological *** findings suggest that targeting PLIN2 to regulate oligodendrocyte progenitor cell ferroptosis may be a potential therapeutic strategy for rescuing myelin damage after cerebral ischemia.

关键词： bioinformatics bulk RNA sequencing ferroptosis ischemic stroke myelin injury oligodendrocyte progenitor cell perilipin-2 single-cell RNA sequencing

Output Consensus of Heterogeneous Linear MASs via Adaptive Event-Triggered Feedback Combination Control

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 285-287页

作者： Shuo yuan Chengpu yu jian Sun the School of Automation Beijing Institute of Technology the Beijing Institute of Technology Chongqing Innovation Center

Dear Editor,This letter studies output consensus problem of heterogeneous linear multiagent systems over directed graphs. A novel adaptive dynamic event-triggered controller is presented based only on the feedback combination of the agent's own state and neighbors' output,which can achieve exponential output consensus through intermittent communication. The controller is obtained by solving two linear matrix equations, and Zeno behavior is excluded.

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Directional Plasmon Filtering in a Two-Dimensional Electron Gas Embedded in High-Index Crystallographic Planes

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Chinese Physics Letters 2014年第3期31卷 133-136页

作者： CHEN jian XU huai-Zhe State Key Laboratory of Software Development Environment and Department of Physics Beihang University Belting 100191

We study theoretically the plasmon excitations in a two-dimensional electron gas （2DEG） with spin-orbit interactions （SOIs） embedded in a （11n） crystallographic plane. We demonstrate that the energy spectra and dielectric functions between the 2DEGs embedded in different crystallographic planes can be related by a unitary transformation. Using the unitary transformation, we find that the anisotropy of plasmon excitations and the directional plasmon filtering （DPF） can be tuned by changing the strengths of SOIs in the high-index planes. There are two advantageous directions [110] and [nn2] for plasmon propagation. Moreover, the anisotropy and the DPF can be smeared out by tuning the strength ratio α/β between the Rashba SOI and the Dresselhaus SOI.

关键词： PLASMONS (Physics) RESEARCH ELECTRON gas -- Research SPIN-orbit interactions (Physics) CRYSTALLOGRAPHY PHYSICS research