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四川省3.6万成年居民健康生活方式遵循情况

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中华疾病控制杂志 2024年第6期28卷 657-663页

作者：查雨欣邓颖何君左明良李希崔建兰张岩许巍何予晋秦小雲王卓四川省疾病预防控制中心慢性非传染性疾病预防控制研究所成都610041 四川省医学科学院四川省人民医院心血管超声及心功能科成都610072 国家心血管病中心北京102308

目的了解四川省成年居民4种健康生活方式的遵循情况和相关影响因素,分析其对全因死亡的潜在健康益处,并提出有针对性的健康促进策略。方法采用多阶段整群抽样的方法,随机抽取四川省8个县(区),调查参与2015年9月―2019年11月心血管病高... 详细信息

目的了解四川省成年居民4种健康生活方式的遵循情况和相关影响因素,分析其对全因死亡的潜在健康益处,并提出有针对性的健康促进策略。方法采用多阶段整群抽样的方法,随机抽取四川省8个县(区),调查参与2015年9月―2019年11月心血管病高危人群早期筛查与综合干预项目的成年居民的4种健康生活方式情况,包括不吸烟、不饮酒或适量饮酒、充足的身体活动、健康饮食。采用多变量回归模型对个人特征与遵循4种健康生活方式的关系进行分析,利用Cox回归模型对全因死亡风险比(hazard ratio,HR)及其95%CI进行估计。结果本研究共纳入36066名35~<75岁常住居民,调查对象中不吸烟者占74.6%、不饮酒或适量饮酒者占96.2%、有充足身体活动者占29.2%、遵循健康饮食者占6.2%,仅有2.7%的调查对象遵循上述所有的4种健康生活方式。女性、老年人、非农民、城市居民、高收入或高学历人群、有心血管病史的对象更有可能遵循所有4种健康生活方式(均P<0.001)。在随访2.4年后发现,坚持≥3种健康生活方式、坚持充足身体活动和不吸烟的人群有更低的全因死亡率风险[调整年龄和性别后,HR=0.47(95%CI:0.22~0.96),HR=0.63(95%CI:0.52~0.75),HR=0.79(95%CI:0.64~0.98)]。结论四川省成年居民对充足身体活动和健康饮食的遵循情况不理想,应作为健康促进的重点方向,并针对不同的危险因素采取针对性措施,以取得更好的防控效果。

关键词：健康生活方式死亡率健康促进

Recent Advances in Microbial Production of Terpenoids from Biomass-derived Feedstocks

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Chemical Research in Chinese Universities 2024年第1期40卷 20-28页

作者： CAO yujin XIAN Mo CAS Key Laboratory of Biobased Materials Qingdao Institute of BioEnergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101P.R.China Shandong Energy Institute Qingdao 266101P.R.China Qingdao New Energy Shandong Laboratory Qingdao 266101P.R.China

Terpenoids are a diverse class of natural products widely used as pharmaceuticals,perfumes,flavors,and ***,terpenoids are obtained from natural sources,such as plants,but their production is limited by the insufficiency of resources and low yields of *** production of terpenoids has emerged as a promising alternative due to that it is sustainable and easy to scale *** review aims to summarize recent advances in microbial production of terpenoids from inexpensive biomass-derived *** pathways and key enzymes involved in terpenoid biosynthesis are *** that can utilize low-cost lignocellulosic feedstocks for terpenoid production are *** challenges and prospects faced by microbial terpenoid production are *** believe that continuous progress in the fields of biomass transformation and synthetic biology will ultimately achieve industrial production of microbial terpenoids.

关键词： Terpenoid Microbial production Biomass-derived feedstock Metabolic pathway

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从《阿凡达》看电影世界设定的对比表达技巧

新闻界 2010年第2期 52-53页

作者：何雨津重庆师范大学重庆400053

电影《阿凡达》通过在空间尺度、空间组成、色彩与形体组成、主角的活动能力与范围、价值取向、个体尊重与社会认同等多方面刻意采取强烈对比的世界设定手段,从而引导观众观影过程中对异星世界的认同和向往。

关键词：阿凡达对比设定

Impact resistance performance and optimization of the sand-EPE composite cushion in rock sheds

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Journal of Mountain Science 2024年第2期21卷 676-689页

作者： YU Bingxin ZHOU Xiaojun TANG Jianhui ZHANG yujin ZHANG Yuefeng School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China

Rock sheds are widely used to prevent rockfall disasters along roads in mountainous *** improve the capacity of rock sheds for resisting rockfall impact,a sand and expandable polyethylene(EPE)composite cushion was proposed.A series of model experiments of rockfall impact on rock sheds were conducted,and the buried depth of the EPE foam board in the sand layer was *** impact load and dynamic response of the rock shed were *** results show that the maximum impact load and dynamic response of the rock shed roof are all significantly less than those of the sand ***,as the distance between the EPE foam board and rock shed roof decreases,the maximum rockfall impact force and impact pressure gradually decrease,and the maximum displacement,acceleration and strain of the rock shed first decrease and then change *** addition,the vibration acceleration and vertical displacement of the rock shed roof decrease from the centre to the edge and decrease faster along the longitudinal direction than that along the transverse *** conclusion,the buffering effect of the sand-EPE composite cushion is better than that of the pure sand cushion,and the EPE foam board at a depth of 1/3 the thickness of the sand layer is appropriate.

关键词： Rockfall Rock shed Impact Composite cushion Buffering effect Dynamic response

Influence of Repetitive Impulse Waveforms on Surface Discharge Characteristics and Insulation Life for Polyimide Film

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 746-755页

作者： Zhiyun Han Qingmin Li yujin Guo Tao Liu Guojing Dong Hanwen Ren State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China Electric Power Research Institute Beijing 100085China Inner Mongolia Electric Economy and Technology Academy Hohhot 010020China

Accelerated insulation aging problems under high frequency repetitive impulses in power electronic transformers are drawing more and more attention in modern power systems. Partial discharge (PD) characteristics including discharge inception voltage, phase distribution and statistical characteristics on polyimide (PI) surface under different impulse waveforms and the insulation life of PI films are studied in this paper. We carry out experiments based on PD and insulation lifetime test systems, using five different types of repetitive impulses, including three bipolar waves and two unipolar waves. The experimental results show that there is little variation in discharge inception voltage under different waveforms, but great variation in phase distribution and statistical characteristics of PD. In addition, insulation life is approximately the same under different waveforms with the same polarity, and the aging rate under bipolar waveforms is larger than that under unipolar waveforms. We explain the differences between the bipolar and unipolar waveforms on insulation life, which can be concluded that the surface charge under unipolar waveform accumulates more significnatly compared with bipolar waveform and decreases the electric filed strength in discharging the air gap and inhibits surface discharge from occurring.

关键词： Insulation life polyimide film power electronic transformer repetitive impulse surface discharge characteristics

Phase transition of multi-component(TiZrVNb)C ceramics—Part II:From single phase to multiple phases via adjusting V content

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Journal of Advanced Ceramics 2024年第5期13卷 689-698页

作者： Qingyi Kong Lei Chen Sijia Huo Kunxuan Li Wenyu Lu yujin Wang Yu Zhou Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150080China Key Laboratory of Advanced Structure‒Function Integrated Materials and Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001China National Key Laboratory of Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China

To address the relatively mediocre mechanical properties of single-phase multi-component carbide ceramics,a phase transition from a single phase to multiple phases was proposed to achieve superior mechanical properties.A series of(TiZrV_(x)Nb)C_(0.8) ceramics with different V contents were fabricated by spark plasma sintering(SPS).The influence of the V content on the phase composition,microstructural evolution,and mechanical properties was investigated in *** transition behavior from a single phase to multiple phases is discovered and *** formation of the Zr-rich phase and Zr-poor phase can be attributed to the increase in lattice distortion and mixed enthalpy caused by the addition of V.A nanometer lamellar structure with a semi-coherent interface obtained via in situ decomposition is reported for the first time in multi-component carbide *** semi-coherent interfaces with high dislocation density and strain concentration effectively improve the mechanical properties,grain refinement,and multi-phase *** optimal comprehensive mechanical properties of the Vickers hardness(26.3 GPa),flexural strength(369 MPa),and fracture toughness(3.1 MPa·m^(1/2))were achieved for the sample with 20 mol%V.

关键词： multi-component ceramics multiple phases microstructure evolution phase decomposition mechanical properties

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含有时滞控制的准零刚度隔振器动力学分析

振动与冲击 2018年第13期37卷 49-55页

作者：李东海赵寿根何玉金李涛北京航空航天大学航空科学与工程学院北京100083

准零刚度隔振器可以通过正负刚度并联来实现。研究了一种由三弹簧系统并联而成的准零刚度隔振器在简谐力激励下的动力学特性,并引入线性位移时滞控制策略。通过平均法分析得到系统在简谐力激励下的响应特性,并利用一阶李亚普洛夫近似稳... 详细信息

准零刚度隔振器可以通过正负刚度并联来实现。研究了一种由三弹簧系统并联而成的准零刚度隔振器在简谐力激励下的动力学特性,并引入线性位移时滞控制策略。通过平均法分析得到系统在简谐力激励下的响应特性,并利用一阶李亚普洛夫近似稳定理论和劳斯-赫尔维茨准则分析了受控系统的稳定性和跳跃现象以及Hopf分叉现象。研究结果表明,时滞控制可以有效地改善准零刚度系统的稳定性,并且能够抑制系统跳跃现象的发生;通过选择合适的控制参数,可以避免系统发生Hopf分叉现象。

关键词：准零刚度隔振器时滞控制稳定性 Hopf分叉

含有时滞控制的准零刚度隔振器的隔振性能研究

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西北工业大学学报 2018年第6期36卷 1168-1175页

作者：李东海赵寿根何玉金李涛北京航空航天大学航空科学与工程学院北京100191

采用一对斜置弹簧作为负刚度元件,与垂直弹簧并联组成准零刚度非线性隔振器,从而增大系统的隔振频率范围。并引入线性位移时滞控制。通过平均法分析得到系统在简谐力激励下的响应特性。在此基础上,研究了该刚度系统在引入线性位移时滞... 详细信息

采用一对斜置弹簧作为负刚度元件,与垂直弹簧并联组成准零刚度非线性隔振器,从而增大系统的隔振频率范围。并引入线性位移时滞控制。通过平均法分析得到系统在简谐力激励下的响应特性。在此基础上,研究了该刚度系统在引入线性位移时滞控制时的力传递特性,给出了时滞控制对力传递率的影响规律和特点。结果表明,无论受控系统是在低频段还是高频段,该隔振器的隔振性能均比等效的线性隔振器要好,而受控系统的隔振性能优于不受控系统。

关键词：准零刚度隔振器时滞控制力传递率

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微博信息传播的热度和持续度研究

情报杂志 2014年第3期33卷 81-87,32页

作者：徐勇肖畅何瑜瑾华南理工大学经济与贸易学院广州510006 中国电信股份有限公司广东移动互联网运营中心广州510006

本文在国内外学者的研究基础之上,结合微博用户的特点,从多主体理论的角度研究微博的信息传播机制,构建基于多主体的微博信息传播模型。用传染病动力系统建模的方法来研究微博热度的影响因素,用Cox比例风险模型研究微博持续度的影响因... 详细信息

本文在国内外学者的研究基础之上,结合微博用户的特点,从多主体理论的角度研究微博的信息传播机制,构建基于多主体的微博信息传播模型。用传染病动力系统建模的方法来研究微博热度的影响因素,用Cox比例风险模型研究微博持续度的影响因素。然后以新浪微博为研究样本对模型进行验证,得出结论:该模型能够很好地描述微博信息的传播机制,适用于分析微博的热度和持续度。最后,根据研究结论对政府的议程设置和企业的微博营销提出一些针对性的管理建议。

关键词：微博信息传播多主体传染病动力学热度持续度