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数字鸿沟对农村老年人社会参与的影响

华南农业大学学报（社会科学版） 2024年第3期23卷 48-60页

作者：崔钰鹏何有世江苏大学管理学院江苏镇江212013

在数字时代与老龄化社会的双重背景下,数字鸿沟对农村老年人社会参与造成的影响亟待关注。基于2020年中国家庭追踪调查数据,运用层次回归和中介效应检验法实证研究数字鸿沟对农村老年人社会参与的影响及作用机制。研究发现:数字鸿沟对... 详细信息

在数字时代与老龄化社会的双重背景下,数字鸿沟对农村老年人社会参与造成的影响亟待关注。基于2020年中国家庭追踪调查数据,运用层次回归和中介效应检验法实证研究数字鸿沟对农村老年人社会参与的影响及作用机制。研究发现:数字鸿沟对农村老年人社会参与有显著负向影响,其中使用沟与知识沟负向作用于农村老年人社会参与,接入沟则正向作用于农村老年人社会参与。数字鸿沟主要通过健康状况、文化资本和社会信任3个渠道影响农村老年人社会参与,且健康状况、文化资本和社会信任均正向作用于农村老年人社会参与。异质性分析发现,相较于女性,数字鸿沟对农村男性老年人社会参与的负向影响效果更大,但在政治参与方面则相反。研究结论可为提升农村老年人社会参与水平、积极应对人口老龄化危机提供参考意见。

关键词：数字鸿沟农村老年人社会参与老龄化

Identification of the cytochrome P450s responsible for the biosynthesis of two types of aporphine alkaloids and their de novo biosynthesis in yeast

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Journal of Integrative Plant Biology 2024年第8期66卷 1703-1717页

作者： Qishuang Li Xiang Jiao Xinyi Li Wenlong shi Ying Ma Xiangmei Tan Jingyi Gan Jimei Liu Jian Yang Jian Wang Baolong Jin Tong Chen Ping Su Yujun Zhao Yifeng Zhang Jinfu Tang Guanghong cui Yun Chen Juan Guo Luqi Huang School of Traditional Chinese Pharmacy China Pharmaceutical UniversityNanjing 211198China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs National Resource Center for Chinese Materia MedicaChina Academy of Chinese Medical SciencesBeijing 100700China Department of Life Sciences Chalmers University of TechnologyGothenburg SE-41296Sweden State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaThe Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Aporphine alkaloids have diverse pharmacological activities;however,our understanding of their biosynthesis is relatively *** studies have classified aporphine alkaloids into two categories based on the configuration and number of substituents of the D-ring and have proposed preliminary biosynthetic pathways for each *** this study,we identified two specific cytochrome P450 enzymes(CYP80G6 and CYP80Q5)with distinct activities toward(S)-configured and(R)-configured substrates from the herbaceous perennial vine Stephania tetrandra,shedding light on the biosynthetic mechanisms and stereochemical features of these two aporphine alkaloid ***,we characterized two CYP719C enzymes(CYP719C3 and CYP719C4)that catalyzed the formation of the methylenedioxy bridge,an essential pharmacophoric group,on the A-and D-rings,respectively,of aporphine *** the functional characterization of these crucial cytochrome P450 enzymes,we reconstructed the biosynthetic pathways for the two types of aporphine alkaloids in budding yeast(Saccharomyces cerevisiae)for the de novo production of compounds such as(R)-glaziovine,(S)-glaziovine,and *** study provides key insight into the biosynthesis of aporphine alkaloids and lays a foundation for producing these valuable compounds through synthetic biology.

关键词： aporphine alkaloids biosynthesis CYP719C CYP80 engineered yeast

Correlation between Neutrophil Percentage-to-albumin Ratio and Coronary Heart Disease Complicated with Diabetes Mellitus

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Medicinal Plant 2024年第2期15卷 43-47页

作者： Wenjing ZHANG Yuhong shi Guilan ZHANG minghui ZHANG Zhoukai cui Jiaying WANG Anjun ZHU Pingquan County Hospital Pingquan 067500China

[Objectives]This study was conducted to explore the relationship between neutrophil percentage-to-albumin ratio(NPAR)and coronary heart disease complicated with diabetes.[Methods]A total of 603 patients with coronary heart disease who underwent coronary angiography in Pingquan County Hospital from January,2023 to December,2023 and met the inclusion criteria were included as the research *** the patients were divided into a coronary heart disease complicated with diabetes group(CAD+T2DM group)(n=298 cases)and a control group(CAD group)(n=305 cases),according to patients medical history,heart color ultrasound and biochemical test *** clinical data,biochemical test results and coronary artery imaging data of patients were recorded,and the Gensini score was *** neutrophil percentage(NEUT%)and albumin count were determined to calculate NPAR.[Results]The NPAR value of the coronary heart disease complicated with diabetes mellitus group was(1.6±0.42),which was significantly higher than that of the control group(1.47±0.49),and the difference was statistically significant(Pmin ratio(NPAR)is closely related to coronary heart disease complicated with diabetes mellitus,and NPAR has clinical application value in the diagnosis of coronary heart disease complicated with diabetes mellitus.

关键词： Neutrophil percentage-to-albumin ratio(NPAR) Gensini score Coronary heart disease Coronary angiography

Hot Deformation Behavior and Workability of a New Ni–W–Cr Superalloy for Molten Salt Reactors

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1453-1466页

作者： Long Liu Zijian Zhou Jie Yu Xinguang Wang Chuanyong cui Rui Zhang Yizhou Zhou Xiaofeng Sun shi‑Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Fushun Special Steel Co. LtdFushun 113000China

The hot deformation behavior of a newly developed Ni–W–Cr superalloy for use in 800℃molten salt reactors(MSRs)was looked into by isothermal compression tests in the temperature range of 1050–1200℃with a strain rate of 0.001–1 s^(−1)under a true strain of *** Arrhenius-type model for the Ni–W–Cr superalloy was constructed by fitting the corrected flow stress *** this model,the effect of dispersion of solid solution elements during thermal deformation on microstructure evolution was considered,as well as the effects of friction and adiabatic heating on the temperature and strain rate-dependent variation of flow *** hot deformation activation energy of the Ni–W–Cr superalloy was 323 kJ/mol,which was less than that of the Hastelloy N alloy(currently used in MSRs).According to the rectified flow stress data,processing maps were *** conjunction with the corresponding deformation microstructures,the flow instability domains of the Ni–W–Cr superalloy were determined to be 1050–1160℃/0.03–1 s^(−1)and 1170–1200℃/0.001–0.09 s^(−1).In these deformation conditions,a locally inhomogeneous microstructure was caused by flow-i.e.,incomplete dynamic recrystallization and hot working parameters should avoid sliding into these *** ideal processing hot deformation domain for the Ni–W–Cr superalloy was determined to be 1170–1200℃/0.6–1 s^(−1).

关键词： Ni-W-Cr Superalloy Hot deformation behavior Constitutive equation Processing map microstructure evolution

Photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkylamination compounds as potential bactericidal agent against Xanthomonas oryzae ***

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Chinese Chemical Letters 2024年第1期35卷 401-405页

作者： Yu shi Zhao-Sheng Zhang Jiang Shao Chen Fu Lan-Tu Xiong Zhao-Dong Li Zi-Ning cui National Key Laboratory of Green Pesticide Integrative Microbiology Research CentreGuangdong Province Key Laboratory of Microbial Signals and Disease ControlCollege of Plant ProtectionSouth China Agricultural UniversityGuangzhou 510642China Henry Fok School of Biology and Agriculture Shaoguan UniversityShaoguan 512005China College of Materials and Energy South China Agricultural UniversityGuangzhou 510642China

A series of photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkylamination derivatives was rationally synthesized based on diversity-oriented synthesis via cross coupling of 1,3-dienes,amines and fluoroalkyl *** reaction featured good function group tolerance and a broad substrate scope,which could be extended to the late-stage modification of bioactive *** activity of all the compounds against Xanthomonas oryzae ***(Xoo)was *** them,compound E14 showed significant activity against Xanthomonas oryzae ***(Xoo)with half maximal effective concentration(EC50)value of 6.61μmol/*** pot experiments,the results showed that E14 could control rice bacterial blight with protective and curative efficiencies of 37.5%and 63.2%at 200μg/mL,***,a plausible mechanism for antibacterial behavior of E14 was proposed by electron microscopy,flow cytometry,reactive oxygen species detection,and biofilm *** current work,it can promote the development of photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkyl amination compounds as prospective antibacterial agent bearing an intriguing mode of action.

关键词： 1,3-Diene-selective fluoroalkylamination derivatives Xanthomonas oryzae pv.oryzae Antibacterial activity Electron microscopy Reactive oxygen Flow cytometry

基于节点特征对抗性攻击的图对比学习鲁棒性验证

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清华大学学报（自然科学版） 2024年第1期64卷 13-24页

作者：邢宇杰王啸石川黄海崔鹏北京邮电大学计算机学院北京100876 北京航空航天大学软件学院北京102206 清华大学计算机科学与技术系北京100084

最近的许多工作已经表明图神经网络在面对图结构扰动以及节点特征扰动的对抗攻击时表现出非鲁棒性,其预测结果可能是不可靠的,图对比学习方法中也存在这一问题。然而已有的鲁棒性测度方法通常与攻击算法、数据标签以及下游任务相关,这... 详细信息

最近的许多工作已经表明图神经网络在面对图结构扰动以及节点特征扰动的对抗攻击时表现出非鲁棒性,其预测结果可能是不可靠的,图对比学习方法中也存在这一问题。然而已有的鲁棒性测度方法通常与攻击算法、数据标签以及下游任务相关,这些在自监督设置下图对比学习的鲁棒性测度中是应当尽量避免的。该文提出了基于节点特征对抗性攻击的图对比学习鲁棒性验证算法,来验证节点特征扰动下的图卷积网络的鲁棒性。考虑到图对比学习模型中正负例对的特性,将图对比学习鲁棒性验证问题定义为对抗样本与目标节点及其负例之间相似度比较的问题,并将该问题形式化建模为一个动态规划问题,从而解决了对攻击算法、数据标签以及下游任务的依赖问题。为了求解该动态规划问题,针对图数据通常采用的二元特征,设计了相应的扰动空间;考虑到图对比学习中负例样本空间过大的挑战,设计了负例样本采样策略来提升求解问题的效率;由于二元离散特征和非线性激活函数使得动态规划问题难于求解,对它们分别采用放松到连续数据域和非线性激活放松的方式,并采用寻找对偶问题的方式进一步提高求解效率。通过充分的实验说明了所提出的图对比学习鲁棒性验证算法的有效性;同时验证了针对特定攻击算法设计的图对比学习模型的鲁棒性不具有可泛化性,面对其他的攻击算法可能表现得更加脆弱;还通过参数实验说明了设计的负例样本采样策略是合理的。

关键词：图对比学习图卷积网络鲁棒性验证对抗攻击对抗训练

MMCUP:融合多模态信息的代码注释自动更新方法

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计算机学报 2024年第1期47卷 172-189页

作者：刘诗凡崔展齐陈翔李莉北京信息科技大学计算机学院北京100101 南通大学信息科学技术学院江苏南通226019

良好的代码注释对于程序维护有着重要价值.但在实际开发过程中,开发人员经常会在更改代码后忽略更新相应的代码注释,导致更新后的代码和注释不一致,对软件可维护性造成影响.现有注释更新方法在进行注释更新时,通常仅将代码视为普通文本... 详细信息

良好的代码注释对于程序维护有着重要价值.但在实际开发过程中,开发人员经常会在更改代码后忽略更新相应的代码注释,导致更新后的代码和注释不一致,对软件可维护性造成影响.现有注释更新方法在进行注释更新时,通常仅将代码视为普通文本进行处理,忽视了代码结构信息.为此,本文提出了一种融合多模态信息的代码注释更新方法MMCUP(Multi-Modal Comment UPdating).MMCUP使用了旧代码注释、代码编辑序列和AST差异序列三种模态的信息来训练基于Transformer架构的模型,以对注释进行更新.实验结果表明,,MMCUP在Accuracy、Recall@5等指标上相较于CUP和HatCUP等方法至少提高了5.8%和4.4%.

关键词：代码注释更新程序理解代码-注释共同演化深度学习序列到序列模型

Hot Compression Behavior and Tensile Property of a Novel Ni-Co-Based Superalloy Prepared by Electron Beam Smelting Layered Solidification Technology

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 283-292页

作者： Yong-Chao Gai Rui Zhang Chuan-Yong cui Zi-Jian Zhou Yi Tan Yi-Zhou Zhou Xiao-Feng Sun Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The hot compression behavior and tensile strength after compression of a new Ni-Co-based superalloy produced using electron beam smelting layered(EBSL)solidification technology were *** compression tests were performed at temperatures of 1120℃and 1150℃,with strain rates of 1 s^(-1) and 0.01 s^(-1),reaching a true strain of *** strength was evaluated at room *** results revealed that this EBSL technology accelerates dynamic recrystallization(DRX),without compromising the strength of alloy.A significant correlation between the volume fraction of DRX and the strain rate was observed,with higher fractions at lower strain rates,leading to higher tensile ***,at the same strain rate,the specimens compressed at 1120℃exhibited higher tensile strength due to undissolvedγ′*** solution and aging heat treatment,the alloy maintained high tensile *** results suggested that the EBSL Ni-Co-based superalloy offers excellent prospects for practical applications.

关键词： Ni-Co-based superalloy Hot deformation Electron beam smelting Tensile strength

微沟槽织构设计对PDMS表面黏-滑摩擦学行为的影响

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摩擦学学报（中英文） 2024年第1期44卷 70-77页

作者：施文斌肖汉崔坤杰王涛时礼平吴玉国李蒙安徽工业大学机械工程学院安徽马鞍山243002 安徽工业大学芜湖技术创新研究院安徽芜湖241002

“黏-滑”现象是软材料表面摩擦学行为典型的特征,易诱发机械系统的振动与噪音等问题.本文中采用激光加工技术在PDMS(Polydimethylsiloxane,聚二甲基硅氧烷)表面加工了沟槽状织构阵列,研究不同参数织构设计对软材料表面“黏-滑”摩擦行... 详细信息

“黏-滑”现象是软材料表面摩擦学行为典型的特征,易诱发机械系统的振动与噪音等问题.本文中采用激光加工技术在PDMS(Polydimethylsiloxane,聚二甲基硅氧烷)表面加工了沟槽状织构阵列,研究不同参数织构设计对软材料表面“黏-滑”摩擦行为的影响.结果表明沟槽织构可以有效抑制软材料表面“黏-滑”行为,降低界面摩擦阻力,但沟槽的作用效能依赖于其倾斜角设计.此外,界面滑动速度和沟槽织构宽度也是影响表面摩擦学行为的主要因素.

关键词： “黏-滑”行为软材料摩擦学黏弹性表面织构

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