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宗族文化对农民创业正规化的影响机制研究

研究与发展管理 2024年第4期36卷 75-87页

作者：徐国长陈万明马永远南京航空航天大学经济与管理学院南京211106

创业正规化是促进农民创业融入现代农业产业、创造规模经济效益的有效途径,也是实现乡村振兴、共同富裕的重要基石。现有研究大多从正式制度视角探讨创业正规化,忽视了宗族文化等非正式制度对农民创业正规化的作用。鉴于此,基于制度理论... 详细信息

创业正规化是促进农民创业融入现代农业产业、创造规模经济效益的有效途径,也是实现乡村振兴、共同富裕的重要基石。现有研究大多从正式制度视角探讨创业正规化,忽视了宗族文化等非正式制度对农民创业正规化的作用。鉴于此,基于制度理论,利用地区族谱数量测度宗族文化,探究宗族文化对农民创业正规化的影响,并探讨了内/外群体社会信任的中介作用和数字化水平的调节作用。研究结果表明:宗族文化抑制了农民创业正规化;内群体社会信任和外群体社会信任在宗族文化与农民创业正规化关系中均发挥了中介作用;进一步地,数字化水平削弱了宗族文化对农民创业正规化的抑制作用。研究结论从非正式制度视角拓展了农民创业正规化的理论认知,并为农民创业实践和地区乡村振兴进程提供了重要借鉴。

关键词：宗族文化创业正规化内群体社会信任外群体社会信任数字化水平农民创业者

Oxidative DNA demethylation mediated by Tet enzymes

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National Science Review 2015年第3期2卷 318-328页

作者： guo-Liang xu Jiemin Wong Institute of Biochemistry and Cell Biology Chinese Academy of Sciences Institute of Biomedical Sciences and School of Life Sciences East China Normal University

DNA modiication, methylation of cytosine(5m C), and oxidation of 5m C to 5-hydroxymethylcytosine(5hm C), 5-formylcytosine(5f C), and 5-carboxylcytosine(5ca C) can have profound efects on genome function in animals. hese modiications are intricately involved in DNA methylation reprograming dynamics during mammalian development. Together, they contribute to cell lineage restriction and maintenance, while also undergoing dynamic changes during cellular transitions and induced *** last ive years have seen an intense research focus on enzymatic DNA demethylation, triggered by the discovery of 5hm C and Tet dioxygenases. In this review, we evaluate recent indings that have provided new insights into the mechanisms underlying DNA demethylation and its efect on developmental regulation.

关键词： DNA demethylation 5m C oxidation Tet dioxygenase TDG epigenetic reprograming

A Novel Three-dimensional Inorganic Open-framework Constructed from [Mo_4O_(16)]_n ^(8n-) Chains Linked through Ag^+

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Chinese Journal of Structural Chemistry 2005年第12期24卷 1452-1456页

作者： guo Hong-xu LIU Shi-Xiong Department of Chemistry Fuzhou University Fuzhou 350002 China Department of Chemtstry Zhangzhou Teacher＇s College Zhangzhou 363000 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou 350002 China

A novel 3-D inorganic bimetallic compound Ag2Mo2O7 has been hydrothermally synthesized and structurally characterized by X-ray diffraction. The compound crystallizes in monoclinic, space group P21/c with a = 6.1274（3）, b = 13.1836（6）, c = 7.8780（3）A, β= 110.673（3）°, V = 595.42（5）A3, Z= 4, Mr= 519.62, Dc = 5.797g/cm^3, F（000） = 936,μ（MoKα） = 10.579 mm^-1, F（000） = 936, the final R = 0.0204 and wR = 0.0477 for 1268 observed reflections with I〉 2σ（I）. In the title compound, the [Mo4O16]n^8n-chains are linked through O-Ag-O bridging bonds to form a 3D network. It represents an unprecedented linking mode between the isopolyoxomolybdate chain and the transition metal oxide cluster. IR, TGA and fluorescence properties of the title compound are also studied.

关键词： polyoxomolybdate molybdenum(Ⅵ) open-framework hydrothermal synthesis crystal structure

Optimal transmission strategy for spatially correlated MIMO systems with channel statistical information

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 615-619页

作者： ZHAO Zhen-shan xu guo-zhi Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China

In real multiple-input multiple-output (MIMO) systems, the perfect channel state information (CSI) may be costly or impossible to acquire. But the channel statistical information can be considered relatively stationary during long-term transmission. The statistical information can be obtained at the receiver and fed back to the transmitter and do not require frequent update. By exploiting channel mean and covariance information at the transmitter simultaneously, this paper investigates the optimal trans- mission strategy for spatially correlated MIMO channels. An upper bound of ergodic capacity is derived and taken as the per- formance criterion. Simulation results are also given to show the performance improvement of the optimal transmission strategy.

关键词： MIMO Optimal transmission strategy Channel statistical information

Acceleration of the EM Algorithm Using the Vector Aitken Method and Its Steffensen Form

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Acta Mathematicae Applicatae Sinica 2017年第1期33卷 175-182页

作者： xu guo Qiu-yue LI Wang-li xu School of Statistics Beijing Normal University College of Science China Agricultural University Center for Applied Statistics School of StatisticsRenmin University of China

Based on Vector Aitken （VA） method, we propose an acceleration Expectation-Maximization （EM） algorithm, VA-accelerated EM algorithm, whose convergence speed is faster than that of EM algorithm. The VA-accelerated EM algorithm does not use the information matrix but only uses the sequence of estimates obtained from iterations of the EM algorithm, thus it keeps the flexibility and simplicity of the EM algorithm. Considering Steffensen iterative process, we have also given the Steffensen form of the VA-accelerated EM algorithm. It can be proved that the reform process is quadratic convergence. Numerical analysis illustrate the proposed methods are efficient and faster than EM algorithm.

关键词： EM algorithm VA-accelerated EM algorithm convergence rate Steffensen iterative

N-丁基-9 H-嘧啶并[4,5-b]吲哚-2-甲酰胺通过NLRP3/Caspase-1抑制巨噬细胞泡沫化及焦亡作用

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中国药理学通报 2024年第6期40卷 1035-1041页

作者：舒志云呼延子旭张文晴谢世顺成鸿源徐国兴李相军吉林大学药学院实验药理与毒理学教研室吉林长春130021 吉林大学药学院药物化学教研室吉林长春130021

目的设计并合成了嘧啶并吲哚类衍生物N-丁基-9 H-嘧啶并[4,5-b]吲哚-2-甲酰胺(BFPI),探讨其是否通过NLRP3/Caspase-1通路抑制巨噬细胞焦亡和泡沫化作用。方法以2,4,6-三乙氧羰基-1,3,5-三嗪和2-氨基吲哚为起始原料合成BFPI,并通过1H NMR... 详细信息

目的设计并合成了嘧啶并吲哚类衍生物N-丁基-9 H-嘧啶并[4,5-b]吲哚-2-甲酰胺(BFPI),探讨其是否通过NLRP3/Caspase-1通路抑制巨噬细胞焦亡和泡沫化作用。方法以2,4,6-三乙氧羰基-1,3,5-三嗪和2-氨基吲哚为起始原料合成BFPI,并通过1H NMR、13 C NMR、ESI-MS对其结构进行表征。将体外培养的小鼠单核巨噬细胞株RAW264.7分为空白组、模型组(PA)组和治疗组(BFPI)组,各组细胞用对应培养液处理24 h后,用MTT法检测其增殖活力,油红O染色检测细胞内脂滴形成情况,并用Western blot和RT-qPCR检测NLRP3、Caspase-1和MCP-1 mRNA和蛋白表达水平。结果与空白组比较,模型组细胞增殖活力明显下降,脂滴形成量明显增加,与模型组比较,治疗组细胞增殖活力明显增加,脂滴形成量明显降低,差异均有统计学意义(P<0.01);与空白组比较,模型组细胞NLRP3、Caspase-1和MCP-1的mRNA和蛋白表达水平均明显增加,与模型组比较,治疗组细胞上述指标表达水平均明显下降,差异有统计学意义(P<0.01)。结论BFPI可通过抑制巨噬细胞NLRP3、Caspase-1和MCP-1的表达进而促进其增殖并抑制脂质吞噬能力,有助于延缓动脉粥化时巨噬细胞来源的泡沫细胞形成。

关键词： N-丁基-9 H-嘧啶并[4,5-b]吲哚-2-甲酰胺 NLRP3 动脉粥样硬化巨噬细胞细胞泡沫化细胞焦亡

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Effects of temperature distribution and level on heat transfer on a rotating free disk

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航空动力学报 2011年第6期26卷 1310-1320页

作者： ZHAO Xi xu guo-qiang LUO Xiang National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China

In gas turbine engines,with the existence of the intense forced convection and significant buoyancy effects,temperature distribution and level on turbine or compressor disks affect the heat transfer characteristics *** this paper,numerical simulations were performed to analyze these influences for a free disk,with the laminar and turbulent flow *** influences of temperature distribution on the heat transfer were observed by using incompressible cooling air,and temperature profiles of nth order monomial and polynomial were assumed on the *** analysis revealed that the heat transfer for two flow states on the free disk is determined by the exponent n of the monomial profile when specifying the rotating Reynolds number;for an arbitrary polynomial profile,the local Nusselt number can be deduced from results of monomial *** study the effects of temperature level on heat transfer singly,monomial profiles were used and the local Nusselt number of compressible and incompressible cooling air were *** both for two flow states,the following conclusions could be drawn: the relative difference of local Nusselt number is mainly controlled by nondimensional local temperature difference,and almost independent of the monomial's coefficient C,exponent n and the rotating Reynolds ***,a correction method for heat transfer of the free disk is presented and verified computationally,with which the local Nusselt number,obtained with a uniform and low temperature profile,can be revised by arbitrary distribution and high temperature magnitude.

关键词： thermal boundary condition temperature boundary condition rotating disk free disk heat transfer

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数字经济赋能工业高质量发展的实证研究

南宁师范大学学报（自然科学版） 2024年第2期41卷 121-131页

作者：赵鹏许国亮赵丽南宁师范大学经济与管理学院广西南宁530001

数字经济是工业发展的强大助力,探究数字经济推动中国工业高质量发展已成为重要课题。基于中国267个地级市2011—2019年的面板数据,采用分位数回归模型、门槛效应模型和空间杜宾模型,实证检验数字经济对工业高质量发展的影响机制和空间... 详细信息

数字经济是工业发展的强大助力,探究数字经济推动中国工业高质量发展已成为重要课题。基于中国267个地级市2011—2019年的面板数据,采用分位数回归模型、门槛效应模型和空间杜宾模型,实证检验数字经济对工业高质量发展的影响机制和空间溢出效应,探讨政府创新偏好对数字经济与工业高质量发展的非线性调节作用的研究发现:数字经济对工业高质量发展的促进作用存在边际效应递增的非线性特征;政府创新偏好存在强化数字经济促进工业高质量发展的非线性调节作用;数字经济对邻近地区工业高质量发展存在虹吸效应。因此,要统筹各地数字经济发展,发挥地方政府的主体作用,弥合数字鸿沟,充分利用数字经济对工业高质量发展的边际递增效应。

关键词：数字经济工业高质量发展政府创新偏好非线性调节作用门槛效应模型空间杜宾模型

Topology Optimization Considering Steady-State Structural Dynamic Responses via Moving Morphable Component(MMC)Approach

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Acta Mechanica Solida Sinica 2022年第6期35卷 949-960页

作者： Jialin Li Youwei Zhang Zongliang Du Weisheng Zhang Xinglin guo xu guo State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsInternational Research Center for Computational MechanicsDalian University of TechnologyDalian116023China Ningbo Institute of Dalian University of Technology Ningbo315016China

This work presents a moving morphable component(MMC)-based framework for solving topology optimization problems considering both single-frequency and band-frequency steady-state structural dynamic *** this work,a set of morphable components are introduced as the basic building blocks for topology optimization,and the optimized structural layout can be found by optimizing the parameters characterizing the locations and geometries of the components *** degree of freedom(DOF)elimination technique is also employed to delete unnecessary DOFs at each *** the proposed approach solves the corresponding optimization problems in an explicit way,some challenging issues(e.g.,the large computational burden related to finite element analysis and sensitivity analysis,the localized eigenmodes in low material density regions,and the impact of excitation frequency on the optimization process)associated with the traditional approaches can be circumvented *** results show that the proposed approach is effective for solving topology optimization problems involving structural dynamic behaviors,especially when high-frequency responses are considered.

关键词： Topology optimization Moving morphable component(MMC) Structural dynamic response Dynamic compliance