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四川师范大学学报（社会科学版） 2004年第6期31卷 25-28页

作者：彭文甫周介铭李世强王广杰四川师范大学资源与环境学院四川成都610068

我国现行土地征用制度存在的种种弊端,不利于耕地保护和维护农民权益。改革和完善现行的土地征用制度,必须以人为本,从保护农民合法的权益出发,明确征地目的和适用范围、制定合理的补偿标准和补偿征地费用、完善征地程序、赋予农民更大... 详细信息

我国现行土地征用制度存在的种种弊端,不利于耕地保护和维护农民权益。改革和完善现行的土地征用制度,必须以人为本,从保护农民合法的权益出发,明确征地目的和适用范围、制定合理的补偿标准和补偿征地费用、完善征地程序、赋予农民更大的土地权益、强化监督机制、配套推进和完善土地征用制度。

关键词：土地征用制度征地补偿土地管理

Cobalamin-dependent radical S-adenosyl-L-methionine protein functions with a partner to successively methylate tricyclic indole alkaloid for chuangxinmycin maturation and derivatization

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Science China Chemistry 2025年第1期 308-316页

作者： Sili wang Jiancheng Huang Yanan Du Wei Huang Yufeng Xue Xiaokun Xu Guannan Zhong Yuanyuan shi Bin Hong Xiaoying Bian Wen Liu State Key Laboratory of Chemical Biology Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of Sciences State Key Laboratory of Microbial Technology Shandong University National Health Commission (NHC) Key Laboratory of Biotechnology for Microbial Drugs Institute of Medicinal BiotechnologyChinese Academy of Medical Science & Peking Union Medical College

Cobalamin(Cbl)-dependent radical S-adenosyl-L-methionine(SAM) proteins constitute the largest collection of the radical SAM superfamily that has hundreds of thousands of individual members. Many of these proteins are involved in the biosynthesis of pharmaceutically important natural products to catalyze chemically demanding reactions. In the biosynthetic pathway of chuangxinmycin(CXM), a unique indole alkaloid antibiotic with potent anti-infective activity, functionalization of the characteristic thiopyrano[4,3,2-cd]indole scaffold by regio-and stereoselective C3-methylation is believed to rely on a Cbl-dependent radical process, which, however, remained to be reconstituted biochemically. We here report the dissection of this enzymatic process, which requires the incorporation of Cxm8, a Cbl-dependent radical SAM protein, with Cxm9, a DUF5825family protein that shares no homology to any proteins of known functions. Cxm8 and Cxm9 function together by forming an unexpected heterodimeric complex that selectively catalyzes C3-methylation of the tricyclic indole-S-hetero ring system in a successive manner, achieving CXM and a recently identified, C3-dimethylated congener. Detailed biochemical characterization,isotope labeling, structural simulation and bioinformatics analysis rationalized the catalysis of the Cxm8/Cxm9 complex and particularly the necessity of the DUF5825 protein for C3-methylase activity. This is the first example that a Cbl-dependent protein acts with a partner to exhibit radical SAM activity.

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FKBP12-6 Knockout Increases Ryanodine Receptors Open Probability during b-adrenergic Stimulation in Mice Cardiac Myocytes

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FKBP12-6 Knockout Increases Ryanodine Receptors Open Probabi...

“基因、进化与生理功能多样性”海内外学术研讨会暨中国生理学会第七届比较生理学学术会议

作者： Yan-Ting Zhao~1,Peng Zhou~1,Zheng Chen~2,Guang-Ju Ji~2,shi-qiang wang~1 1 State Key Laboratory of Biomembrane and Membrane Biotechnology,College of Life Sciences, Peking University 2 Institute of Biophysics,Chinese Academy of Sciences,Beijing 100871

FK506 binding protein 12.6（FK-BP12.6） is the protein in the ryanodine receptor complex,but its function is controversial in different reported *** conclude that FK-BP12.6 stabilizes ryanodine receptors（RyRs） but some conclude that it has no effect on *** published work of FKBP12.6 effect on RyRs is demonstrated by lipid bilayer experiment,which destroys the in situ environment around FKBP12. 6 and ***,we employed two methods to test FKBP12.6 function directly in RyR complex in intact cardiac ***,using loose-seal patch clamp combined with confocal imaging,we gave the cell membrane a local depolarization to～0mV just below the pipette,at the same time recorded the Ca fluorescent signals,as sparklet from L-type calcium channel（LCC） and spark from *** found that the spark amplitude was decreased and the LCC-RyR coupling latency was shortened in FKBP12.6 knockout mice （KO）.Analyzation of spark flux revealed that the quantal nature of RyR Ca release observed in WT was diminished in KO,indicating that the coupled state of RyR Ca release channel was destroyed when FKBP12.6 was dissociated from RyR *** using isoproterenol（ISO）, a b-adrenergic receptors agonist,we found that the LCC-RyR coupling latency in KO myocytes was much shorter,more sparks and Ca waves occurred compared with ISO treated WT myocytes. We also certified the above results in rat cardiac myocytes pharmacologically,using FK506,the drug proved to dissociate FKBP12.6 from RyR ***,using whole cell patch clamp with confocal imaging,we gave cells a high voltage depolarization（+ 160mV） to make sure all the available LCCs were open,then repolarized to different voltages（-70-120 mV） to make different *** found that FK506 with ISO together induced higher Ca transient, whatever i was small（at higher repolarization voltages） or big（at lower repolarization voltages）. Together,we conclude that FKBP12.6 is important to maintain the quantal nature of RyR Ca release channe

关键词： B-adrenergic FKBP12.6 Isoproterenol Ryanodine receptor Spark

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液滴撞击超疏水管状壁面的动态特性研究

热科学与技术 2017年第4期16卷 280-286页

作者：刘晓华赵一鸣陈石沈胜强王斯琦大连理工大学能源与动力学院辽宁大连116024 大连理工大学化工与环境生命学部辽宁大连116024

利用相界面追踪的CLSVOF(coupled level set and volume of fluid)方法,对液滴在不同速度下撞击超疏水管状壁面的演化过程展开研究。研究结果表明,不同初速度会对液滴在管壁上的动态特性产生较大影响。当撞击速度较小时,液膜会以整体的... 详细信息

利用相界面追踪的CLSVOF(coupled level set and volume of fluid)方法,对液滴在不同速度下撞击超疏水管状壁面的演化过程展开研究。研究结果表明,不同初速度会对液滴在管壁上的动态特性产生较大影响。当撞击速度较小时,液膜会以整体的形态反弹;继续增大撞击速度后,由于受到外缘液膜的牵扯,液膜内部开始出现断裂;撞击速度足够大时,液膜发生解体破碎。同时给出了对于初速度在2.00m/s以内、直径为2.58mm的水滴撞击管径为8.00mm的超疏水壁面时运动状态发生转变的临界条件。

关键词：液滴撞击超疏水壁面管状壁面动态特性

First-principles study of the co-effect of carbon doping and oxygen vacancies in ZnO photocatalyst

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Chinese Physics B 2021年第2期30卷 419-425页

作者： Jia shi Lei wang qiang Gu Department of Physics University of Science and Technology BeijingBeijing 100083China

Although tuning band structure of optoelectronic semiconductor-based materials by means of doping single defect is an important approach for potential photocatalysis application,C-doping or oxygen vacancy(Vo)as a single defect in ZnO still has limitations for photocatalytic ***,the influence of co-existence of various defects in ZnO still lacks sufficient ***,we investigate the photocatalytic properties of ZnOx C0.0625(x=0.9375,0.875,0.8125),confirming that the co-effect of various defects has a greater enhancement for photocatalytic activity driven by visible-light than the single defect in *** clarify the underlying mechanism of co-existence of various defects in ZnO,we perform systematically the electronic properties calculations using density functional *** is found that the coeffect of C-doping and Vo in ZnO can achieve a more controllable band gap than doping solely in ***,the impact of the effective masses of ZnO_(x)C_(0.0625)(x=0.9375,0.875,0.8125)is also taken into *** comparison with heavy Vo concentrations,the light Vo concentration(x=0.875)as the optimal component together with C-doping in ZnO,can significantly improve the visible-light absorption and benefit photocatalytic activity.

关键词： first-principles theory electron density of states and band structure of crystalline solids Ⅲ-ⅤandⅡ-Ⅵsemiconductors

富血小板血浆干预细胞自噬和凋亡治疗骨关节炎

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中国组织工程研究 2025年第13期29卷 2802-2811页

作者：王耀敏张克凡王德宁任强李健石辉滨州医学院附属医院山东省滨州市256600 滨州医学院山东省滨州市264003

背景:富血小板血浆通过调节自噬和凋亡细胞因子、信号转导通路等方面在干预骨关节炎发展过程中发挥了重要作用。目的:总结近年来富血小板血浆在骨关节炎中发挥作用的细胞因子与信号通路,以及与软骨细胞自噬和凋亡的相关性,为未来治疗骨... 详细信息

背景:富血小板血浆通过调节自噬和凋亡细胞因子、信号转导通路等方面在干预骨关节炎发展过程中发挥了重要作用。目的:总结近年来富血小板血浆在骨关节炎中发挥作用的细胞因子与信号通路,以及与软骨细胞自噬和凋亡的相关性,为未来治疗骨关节炎提供有效的靶点。方法:在中国知网、万方数据库、维普、PubMed、Web of Science和Medline数据库进行文献检索,以“富血小板血浆,软骨细胞,细胞凋亡,细胞自噬,骨关节炎,细胞因子,信号通路”作为中文检索词,以“platelet-rich plasma,chondrocyte,apoptosis,autophagy,osteoarthritis,cytokines,signaling pathway”作为英文检索词,对最终纳入的66篇文献进行了系统性的总结和归纳。结果与结论:现有研究显示富血小板血浆能够通过多种途径促进软骨修复,助力骨组织愈合,其主要分为3个方面:①富血小板血浆参与调控了微自噬小体的延伸、闭合与成熟,并在特定条件下促进软骨细胞巨自噬和分子伴侣介导的细胞自噬,促进LC3Ⅱ/Ⅰ、Beclin1等自噬相关因子的表达,抑制P62/SQSTM1的表达,目前尚未有明确的研究直接探讨富血小板血浆对热休克蛋白的具体作用,未来在这一领域值得进一步研究;②富血小板血浆释放的各类生长因子抑制促凋亡因子Caspase、白细胞介素1β、肿瘤坏死因子α的表达,促进抗凋亡因子Bcl-2的表达,阻止软骨细胞凋亡和变性;③富血小板血浆通过激活PI3K/AKT/mTOR信号通路、NF-κB信号转导通路、死亡受体通路、线粒体应激通路等途径,抑制Bax和Caspase的表达,阻止细胞色素c的释放,从而抑制软骨细胞死亡和坏死性凋亡。综合而言,富血小板血浆促进软骨修复、支持软骨再生及发挥抗炎作用,其在软骨细胞中实现生物效应通常依赖于细胞自噬和凋亡相关细胞因子及信号通路的调控。

关键词：富血小板血浆软骨细胞细胞凋亡细胞自噬骨关节炎细胞因子信号通路

Flow structure and unsteady fluctuation with separation over a two-dimensional backward-facing step

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Journal of Hydrodynamics 2019年第6期31卷 1204-1217页

作者： Fang-fang wang shi-qiang Wu Biao Huang State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China Smart Cities Institute Zhengzhou UniversityZhengzhou 450001China

The flow over a backward-facing step(BFS)is a typical separation and reattachment *** flow structures and unsteady mechanisms are still not well *** this paper,the global velocity fields of a BFS are obtained by a synchronous particle image velocimetry(PIV)system with Reh=5345(Reynolds number)and Er=2(expansion ratio).Flow structures are distinguished and defined by the fraction of the negative velocity(upn).The reattachment zone(Lr)is quantitatively defined as(u0.9,u/0.1)on the bottom *** distribution of the large-scale vortices couples well with the divided flow structures and their temporal evolution presenting four stages(forming,developing,shedding and redeveloping)when travel *** unsteady motions with various low frequencies are well explained by the coherent vortices and flow *** the unsteady low frequency motions,the Kelvin Helmholtz(KH)vortices and the oscillation of Xr(OX)come likely from the free shear *** KH vortices contribute to the unsteadiness of the temporal flow,and the OX is the primary response to the vortical fluctuations.

关键词： Backward-facing step flow structure large-scale vortices unsteady motion free shear layer

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用锁相技术实现对小型直流电机的恒速控制

微电机 2001年第6期34卷 55-56,59页

作者：赵世强王宽仁赵满西安空军工程大学电讯工程学院陕西西安710077

叙述了用锁相技术实现对直流电机恒速控制的组成框图、工作原理 ,讨论了为保证系统稳定工作应具有的回路传递函数及其参数选择。

关键词： PLL 小型直流电机恒速控制锁相技术原理控制电路

Effect of growth time on morphology and photovoltaic properties of ZnO nanowire array films

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Rare Metals 2011年第6期30卷 676-680页

作者： YANG Weiguang wang Yali ZHEN qiang shi Weimin Department of Electronic Information Materials School of Materials Science and Engineering Shanghai University Shanghai 200072 China Nano-Science and Nano-Technology Research Center School of Materials Science and Engineering Shanghai University Shanghai 200444 China

Single-crystalline ZnO nanowire arrays with different aspect ratios and nanowire densities were prepared by the hydrothermal growing method using polyethyleneimine （PEI） as a surfactant. PEI can only hinder the lateral growth of the ZnO nanowires, which is observed by high resolution transmission electron microscopy （HRTEM） analysis. Dye-sensitized solar cells were assembled by the ZnO nanowire arrays with different thicknesses, which can be controlled by the growing time and characterized using photocurrent-voltage measurements. Their photocurrent densities and energy allover conversion efficiencies increased with increasing ZnO nanowire lengths. Short-circuit current density of 4.31 ***-2 and allover energy conversion efficiency of 0.87% were achieved with 12.9-μm-long ZnO nanowire arrays.

关键词： inorganic non-metal materials ZnO nanowires hydrothermal growth morphology