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THE APPLICATION OF COBB-DOUGLAS FUNCTION IN FORECASTING THE DURATION OF INTERNET PUBLIC OPINIONS CAUSED BY THE FAILURE OF PUBLIC POLICIES

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Journal of Systems Science and Systems Engineering 2018年第5期27卷 632-655页

作者： Xuefan Dong Ying Lian Ding Li yijun liu Institutes of Science and Development Chinese Academy of Sciences Beijing 100090 China University of Chinese Academy of Sciences Beijing 100190 China Institute of Development Southwest University of Finance and Economics Chengdu 610074 China

Gushes of Internet public opinions may trigger unexpected incidents that significantly affectsocial security and stability, especially for ones caused by the failure of public policies. Therefore,forecasting this kind of Interact public opinions is of great significance. The duration could be citedas one of the most direct indicators that can reflect the severity of a specific Internet public opinioncase. Based on this background, this paper aims to find the factors that may affect the duration of Internet public opinions, and accordingly proposes a model that can accurately predict the durationbefore the release of public policies. Specifically, an index system including 8 factors by consideringfour dimensions, namely, object, environment, reality （offline）, and the network （online）, isestablished. In addition, based on the dataset containing 23 typical Internet public opinion casescaused by the failure of public policies, 9 prediction models are gained by applying the multivariatelinear regression model, multivariate nonlinear regression model, and the Cobb-Douglas function.

关键词： Public policy internet public opinion multivariate linear regression model multivariatenonlinear regression model Cobb-Douglas production function

基于FMV35S的数字聚合酶链式反应方法定量检测转基因作物

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食品科学 2024年第11期45卷 278-284页

作者：刘奕君闫伟龙丽坤马月何禹璇赵宁李飞武张斯童吉林农业大学生命科学学院吉林长春130061 吉林省农业科学院农业质量标准与检测技术研究所吉林长春130033

以含有FMV35S标记基因的大豆转化体MON87705为材料,利用实时聚合酶链式反应(real-timepolymerase chain reaction,real-time PCR)和数字PCR(digital PCR,dPCR)技术,建立一种转基因作物的定量检测方法。通过real-time PCR法对扩增体系测试,建立的检测方法对FMV 35S标记基因具有高度特异性;利用双重微滴式dPCR进行定量检测参数的测定,结果表明:在基因组DNA 0.005~20 ng/μL质量浓度范围,靶标基因的测量拷贝数与理论拷贝数具有良好的线性关系;dPCR方法对FMV 35S标记基因的检出限可达到5 copies,定量限为0.1%。利用两个dPCR平台,对不同含量的转基因作物的盲样进行测定,内标准基因和外源特异性片段的双重、三重测定,均获得准确的定量结果,数据可靠,再现性良好。因此本研究建立的基于筛选标记基因FMV 35S的转基因dPCR定量检测方法在满足转基因成分定量检测标准的参数要求的同时,能够进一步提高检测效率,可为转基因作物成分定量提供一种准确、简便的检测技术。

关键词：转基因筛选标记数字PCR FMV35S 定量检测

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健康不平等的研究方法及角度

职业与健康 2024年第7期40卷 992-999页

作者：刘翊珺袁磊孙金海海军军医大学卫生勤务系健康管理学教研室上海200433

近年来,我国经济迅速发展,居民生活水平显著提高,与此同时,社会贫富差距、城乡差异等现象加剧了我国居民的健康不平等,促进健康公平性已成为我国健康领域研究的热点,这对于健康中国建设具有重要意义。本文旨在回顾国内外健康不平等测量... 详细信息

近年来,我国经济迅速发展,居民生活水平显著提高,与此同时,社会贫富差距、城乡差异等现象加剧了我国居民的健康不平等,促进健康公平性已成为我国健康领域研究的热点,这对于健康中国建设具有重要意义。本文旨在回顾国内外健康不平等测量及分解相关研究,主要从社会经济层面健康不平等、医疗保健健康不平等综述了常用的指标与研究方法,并从数据指标选择、研究对象、方法与角度等方面进行归纳,以期为我国健康不平等相关问题的进一步探讨提供依据。

关键词：健康不平等健康状况测量分解社会经济因素

不同菠萝叶渣添加量对赤灵芝发酵基质营养成分及体外抗氧化活性研究

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四川农业大学学报 2024年第1期42卷 197-206页

作者：刘义军李盖林丽静刘佳梦陈嘉恩黎智韵陈港华南理工大学轻工科学与工程学院广州510641 中国热带农业科学院农产品加工研究所海南省果蔬贮藏与加工重点实验室广东湛江524001 广东收货罐头食品有限公司广东湛江524100

【目的】揭示不同菠萝叶渣添加量对赤灵芝发酵基质营养成分和体外抗氧化活性的影响,为菠萝叶渣的开发利用提供了新的基础数据支撑。【方法】采用全自动氨基酸分析仪、OPLA-DA结合S-plot等仪器和方法分析发酵基质中粗纤维、多糖、总萜、... 详细信息

【目的】揭示不同菠萝叶渣添加量对赤灵芝发酵基质营养成分和体外抗氧化活性的影响,为菠萝叶渣的开发利用提供了新的基础数据支撑。【方法】采用全自动氨基酸分析仪、OPLA-DA结合S-plot等仪器和方法分析发酵基质中粗纤维、多糖、总萜、水解氨基酸和游离氨基酸等营养成分,以及赤灵芝发酵基质水提物的羟基自由基清除能力差异、DPPH自由基清除能力和总抗氧化能力等体外抗氧化活性的变化规律进行分析。【结果】菠萝叶渣胁迫下促进赤灵芝发酵基质中粗纤维降解、释放多糖含量;对赖氨酸和甘氨酸代谢路径具有显著的调节作用含量;游离氨基酸中肌氨酸、a-氨基己二酸呈现出增加的趋势,其他氨基酸整体上呈现出下降的趋势。其中天冬氨酸和苏氨酸等8种游离氨基酸含量差异显著,且不同菠萝叶渣添加量下,存在特异性氨基酸成分;菠萝叶渣有助于提高赤灵芝发酵基质水提物的羟基自由基清除能力和总抗氧化能力,降低DPPH自由基清除能力。【结论】不同菠萝叶渣添加量对赤灵芝发酵基质粗纤维、氨基酸组成以及相关代谢路径具有不同的调节作用。

关键词：菠萝叶渣灵芝抗氧化活性发酵

Fast multipole boundary element analysis of 2D viscoelastic composites with imperfect interfaces

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Science China(Technological Sciences) 2010年第8期53卷 2160-2171页

作者： ZHU XingYi CHEN WeiQiu HUANG ZhiYi liu yijun Department of Civil Engineering Zhejiang UniversityZijingang CampusHangzhou 310058China Department of Engineering Mechanics Zhejiang UniversityYuquan CampusHangzhou 310027China Department of Mechanical Engineering University of CincinnatiCincinnatiOhio 45221-0072USA

A fast multipole boundary element method(FMBEM)is developed for the analysis of 2D linear viscoelastic composites with imperfect viscoelastic *** transformed fast multipole formulations are established using the time domain method. To simulate the viscoelastic behavior of imperfect interfaces that are frequently encountered in practice,the Kelvin type model is *** FMBEM is further improved by incorporating naturally the interaction among inclusions as well as eliminating the phenomenon of material *** all the integrals are evaluated analytically,high accuracy and fast convergence of the numerical scheme are *** numerical examples,including planar viscoelastic composites with a single inclusion or randomly distributed multi-inclusions are *** numerical results are compared with the developed analytical solutions,which illustrates that the proposed FMBEM is very efficient in determining the macroscopic viscoelastic behavior of the particle-reinforced composites with the presence of imperfect *** laboratory measurements of the mixture creep compliance of asphalt concrete are also compared with the prediction by the developed model.

关键词： boundary element method fast multipole method viscoelasticity imperfect interface multi-inclusion composite

低对比剂摄入量能谱肺动脉成像虚拟平扫代替胸部平扫的可行性

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中国医学影像学杂志 2024年第9期32卷 956-960页

作者：方鑫刘义军王旭李贝贝姜健张竞颐大连医科大学附属第一医院放射科

目的探讨能谱CT虚拟平扫技术在肺动脉成像（CTPA）中代替胸部平扫降低患者辐射剂量的可行性。资料与方法前瞻性收集2022年2—11月于大连医科大学附属第一医院行CTPA检查的56例患者，均接受常规胸部平扫及能谱CTPA增强扫描。分别测量... 详细信息

目的探讨能谱CT虚拟平扫技术在肺动脉成像（CTPA）中代替胸部平扫降低患者辐射剂量的可行性。资料与方法前瞻性收集2022年2—11月于大连医科大学附属第一医院行CTPA检查的56例患者，均接受常规胸部平扫及能谱CTPA增强扫描。分别测量胸部平扫和虚拟平扫图像上胸主动脉、肺动脉主干、竖脊肌及肺尖层面、气管隆嵴层面、肺底层面的肺实质CT值及噪声，并计算胸主动脉、肺动脉信噪比、对比噪声比。对两组图像质量及碘残留进行主观评价，并检验主观评分的一致性。记录患者剂量长度乘积、CT容积剂量指数及对比剂用量。比较胸部平扫和虚拟平扫图像各感兴趣区CT值、信噪比、对比噪声比、辐射剂量和主观评分。结果 2名医师的主观评分一致性较好（Kappa=0.984～0.992,P0.05）；肺动脉及胸主动脉信噪比、对比噪声比差异无统计学意义（P>0.05）。用CTPA的虚拟平扫代替常规胸部平扫，患者辐射剂量由（7.27±1.74）mSv减少至（3.26±0.84）mSv，减少约55%。结论 CTPA虚拟平扫可代替胸部常规CT平扫用于肺部疾病筛查，大幅降低患者的辐射剂量。

关键词：肺动脉成像体层摄影术,X线计算机造影剂噪声信噪比辐射剂量胸部

ZnO@MOF@PANI core-shell nanoarrays on carbon cloth for high-performance supercapacitor electrodes

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Journal of Energy Chemistry 2019年第8期28卷 124-131,I0005页

作者： Chunmei Zhu Ying He yijun liu Natalia Kazantseva Petr Saha Qilin Cheng Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and Engineering East China University of Science and TechnologyShanghai 200237 China Centre of Polymer Systems Tomas Bata University in Zlinnam. T. G. Masaryka 5555 760 01 Zlin Czechia

Hierarchical ZnO@metal-organic framework @polyaniline(ZnO@MOF@PANI) core-shell nanorod arrays on carbon cloth has been fabricated by combining electrodeposition and hydrothermal method. Well-ordered Zn O nanorods not only act as a scaffold for growth of MOF/PANI shell but also as Zn source for the formation of MOF. The morphology of ZnO@MOF@PANI composite is greatly influenced by the number of PANI electrodeposition cycles. Their structural and electrochemical properties were characterized with different techniques. The results indicate that the Zn O@MOF@PANI with 13 CV cycles of PANI deposition demonstrates the maximum specific capacitance of 340.7 F g-1 at 1.0 A g-1, good rate capability with84.3% capacitance retention from 1.0 to 10 A g-1 and excellent cycling life of 82.5% capacitance retention after 5000 cycles at high current density of 2.0 A g-1. This optimized core-shell nanoarchitecture endows the composite electrode with short ion diffusion pathway, rapid ion/electron transfer and high utilization of active materials, which thus result in excellent electrochemical performance of the ternary composite.

关键词： Metal-oragnic framework Polyaniline Core-shell nanoarrays Supercapacitor Electrochemical properties

Study on Influence of Crack on the Blade Status Using FBGs

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Photonic Sensors 2018年第1期8卷 63-69页

作者： Gang XU Lei LIANG Jianzhi LI Huaping MEI Hongli LI yijun liu National Engineering Laboratory of Fiber Optic Sensing Technology Wuhan University of Technology Wuhan 430070 China The Key Laboratory for Health Monitoring and Control of Large Structures Shijiazhuang 050043 China School of Mechanical Engineering Hubei Engineering University Xiaogan 432000 China

The status detection for rotating parts is difficult since the sensor is influenced by the rotation in the inflammable, explosive, and strong magnetic environment. Based on the fiber Bragg grating sensing technology, this paper studies the influence of the natural frequency and deformation of a rotor blade affected by the size of crack in the blade. Test results show that the speed of the equipment and blade excited vibration frequency are two main factors or deformation and vibration frequency of the blade. With an increase in the crack depth, the blade deformation is increased while the stimulated natural frequency of the blade is decreased; at a low rotational speed, the deformation is mainly caused by the rotating speed of the blade. On the contrary, the vibration blade itself contributes to the deformation at a high speed. During the process of full speed rotation, the influence of the rotational speed on the blade deformation almost remains the same, and the influence of the natural vibration on blade deformation is increased with an increase in the rotational speed.

关键词： Rotor blade fiber Bragg grating crack depth rotational speed blade frequency blade deformation

羊栖菜多糖组成结构药理活性及其应用研究进展

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农产品加工 2024年第14期 75-79,86页

作者：贾璐铭赵菲刘怡君蒋丹大连海洋大学食品科学与工程学院辽宁大连116023

羊栖菜是一种海洋孢子植物,系褐藻门马尾藻科马尾藻属。羊栖菜藻体肥厚多汁,不仅富含多糖、蛋白质、必需氨基酸、多不饱和脂肪酸、膳食纤维、维生素和矿物质,具有丰富的营养价值,而且具有药用价值。多糖广泛存在于动植物和微生物等有机... 详细信息

羊栖菜是一种海洋孢子植物,系褐藻门马尾藻科马尾藻属。羊栖菜藻体肥厚多汁,不仅富含多糖、蛋白质、必需氨基酸、多不饱和脂肪酸、膳食纤维、维生素和矿物质,具有丰富的营养价值,而且具有药用价值。多糖广泛存在于动植物和微生物等有机体中,是生物体内除蛋白质和核酸外又一类重要的高分子化合物。羊栖菜多糖是从羊栖菜中提取的一种水溶性多糖,主要由褐藻酸、岩藻聚糖硫酸酯和褐藻淀粉组成,在生物体细胞膜间的穿透能力强。有研究表明,羊栖菜多糖在抗氧化、抗肿瘤、抗衰老、降血糖、调节肠道菌群等方面表现出显著的药理活性。参考近年来对羊栖菜的研究,综述了羊栖菜多糖的组成结构、药理活性及其应用,为进一步研究提供参考。

关键词：羊栖菜多糖组成结构药理活性应用