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Optimization Design of the Multi-Layer Cross-Sectional Layout of An Umbilical Based on the GA-GLM

China Ocean Engineering 2024年第2期38卷 247-254页

作者： YANG Zhi-xun yin xu FAN Zhi-rui YAN Jun LU Yu-cheng SU Qi MAO Yandong WANG Hua-lin Institute of marine machinery College of Mechanical and Electrical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDepartment of Engineering MechanicsDalian University of TechnologyDalian 116024China Ningbo Institube of Dalian University of Technology Ningbo 315040China

Marine umbilical is one of the key equipment for subsea oil and gas exploitation,which is usually integrated by a great number of different functional components with multi-layers.The layout of these components directly affects manufacturing,operation and storage performances of the umbilical.For the multi-layer cross-sectional layout design of the umbilical,a quantifiable multi-objective optimization model is established according to the operation and storage requirements.Considering the manufacturing factors,the multi-layering strategy based on contact point identification is introduced for a great number of functional components.Then,the GA-GLM global optimization algorithm is proposed combining the genetic algorithm and the generalized multiplier method,and the selection operator of the genetic algorithm is improved based on the steepest descent method.Genetic algorithm is used to find the optimal solution in the global space,which can converge from any initial layout to the feasible layout solution.The feasible layout solution is taken as the initial value of the generalized multiplier method for fast and accurate solution.Finally,taking umbilicals with a great number of components as examples,the results show that the cross-sectional performance of the umbilical obtained by optimization algorithm is better and the solution efficiency is higher.Meanwhile,the multi-layering strategy is effective and feasible.The design method proposed in this paper can quickly obtain the optimal multi-layer cross-sectional layout,which replaces the manual design,and provides useful reference and guidance for the umbilical industry.

关键词： umbilical cross-sectional layout multi-layers GA-GLM optimization

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Spatiotemporal Pattern of Cultivated Land Pressure and Its Influencing Factors in the Huaihai Economic Zone, China

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Chinese Geographical Science 2023年第2期33卷 287-303页

作者： LI Yi FANG Bin LI Yurui FENG Weilun yin xu School of Geography Nanjing Normal UniversityNanjing 210023China Research Center of New Urbanization and Land Problem Nanjing Normal UniversityNanjing 210023China Jiangsu Provincial Geographic Information Resources Development and Utilization Cooperative Innovation Center Nanjing 210023China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Key Laboratory of Regional Sustainable Development Modeling Chinese Academy of SciencesBeijing 100101China School of Geographic Science Hebei Normal UniversityShijiazhuang 050024China

Cultivated land pressure represents a direct reflection of grain security. Existing relevant studies rarely approached the spatiotemporal pattern of cultivated land pressure or the spatial heterogeneity of its influencing factors from the level of economic zones.Taking the Huaihai Economic Zone(HEZ), China for case analysis, this study investigated the spatiotemporal pattern of cultivated land pressure in diverse periods from 2000 to 2018 based on a modified cultivated land pressure index and spatial correlation models. On this basis, it explored the influencing factors of the spatial differentiation of cultivated land pressure in the late stage of the study using geographical detector as well as multi-scale geographically weighted regression model. The results indicated that: 1) in the study period, the global cultivated land pressure index of the study area decreased gradually, but cultivated land pressure increased locally in a significant way, especially in the central and southern Shandong Province;2) the spatial pattern of cultivated land pressure manifested global clustering features. Hot and secondary-hot spots presented a narrowing and clustering trend, whereas cold and secondary-cold spots manifested a spreading and clustering trend;3) average slope, the proportion of non-grain crops, population urbanization rate, and multiple cropping index have significant effects on the spatial differentiation of cultivated land pressure. The former three factors were positively correlated with cultivated land pressure, and the last factor was negatively correlated with cultivated land pressure;and 4) the amount of cultivated land has increased in the central and southern Shandong Province through land consolidation which, nonetheless, failed to improve the grain production. In regards to major grain producing areas similar to the HEZ in China, the authors suggest that great importance should be given to the balance of the quality and quantity of cultivated land, the optimization of agricultural production factors an

关键词： cultivated land pressure spatiotemporal pattern influencing factors Huaihai Economic Zone China

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Unactivated C(sp^(3))–H functionalization via vinyl cations

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Science China Chemistry 2022年第1期65卷 20-30页

作者： Xi-Jia Liu yin xu Conghui Tang Peng-Cheng Qian Long-Wu Ye Key Laboratory of Environmental Functional Materials Technology and Application of Wenzhou City College of Chemistry&Materials EngineeringInstitute of New Materials&Industry TechnologyWenzhou UniversityWenzhou 325035China Key Laboratory of Chemical Biology of Fujian Province State Key Laboratory of Physical Chemistry of Solid SurfacesCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Direct functionalization of inert C(sp^(3))–H bonds is a topic of immense contemporary interest and exceptional value in organic synthesis.The recent research has established a novel and practical protocol which features the engagement of vinyl cation species to functionalize C(sp^(3))–H bonds.The discussion of the topic is arranged by the strategies to generate the reactive intermediates,including ionization of vinyl triflates,addition of electrophiles to alkynes,tandem cyclization of enynes or diynes,and decomposition ofβ-hydroxy-α-diazo ketones.This review closes with a personal perspective on the dynamic research area of unactivated C(sp^(3))–H functionalization via vinyl cations.Hopefully,it will provide timely illumination and beneficial guidance for organic chemists who are interested in this area.Meanwhile continued development of the field is strongly anticipated in the future.

关键词： C(sp^(3))-H functionalization vinyl cation homogeneous catalysis cyclization

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Recombinant adeno-associated virus 8-mediated inhibition of microRNA let-7a ameliorates sclerosing cholangitis in a clinically relevant mouse model

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World Journal of Gastroenterology 2024年第5期30卷 471-484页

作者： Hui Hua Qian-Qian Zhao Miriam Nkesichi Kalagbor Guo-Zhi Yu Man Liu Zheng-Rui Bian Bei-Bei Zhang Qian Yu yin-Hai xu Ren-Xian Tang Kui-Yang Zheng Chao Yan Jiangsu Key Laboratory of Immunity and Metabolism Department of Pathogenic Biology and ImmunologyNational Demonstration Center for Experimental Basic Medical Science EducationLaboratory of Infection and ImmunityXuzhou Medical UniversityXuzhou 221004Jiangsu ProvinceChina Department of Laboratory Medicine The Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221002Jiangsu ProvinceChina

BACKGROUND Primary sclerosing cholangitis(PSC)is characterized by chronic inflammation and it predisposes to cholangiocarcinoma due to lack of effective treatment options.Recombinant adeno-associated virus(rAAV)provides a promising platform for gene therapy on such kinds of diseases.A microRNA(miRNA)let-7a has been reported to be associated with the progress of PSC but the potential therapeutic implication of inhibition of let-7a on PSC has not been evaluated.AIM To investigate the therapeutic effects of inhibition of a miRNA let-7a transferred by recombinant adeno-associated virus 8(rAAV8)on a xenobiotic-induced mouse model of sclerosing cholangitis.METHODS A xenobiotic-induced mouse model of sclerosing cholangitis was induced by 0.1% 3,5-Diethoxycarbonyl-1,4-Dihydrocollidine(DDC)feeding for 2 wk or 6 wk.A single dose of rAAV8-mediated anti-let-7a-5p sponges or scramble control was injected in vivo into mice onset of DDC feeding.Upon sacrifice,the liver and the serum were collected from each mouse.The hepatobiliary injuries,hepatic inflammation and fibrosis were evaluated.The targets of let-7a-5p and downstream molecule NF-κB were detected using Western blot.RESULTS rAAV8-mediated anti-let-7a-5p sponges can depress the expression of let-7a-5p in mice after DDC feeding for 2 wk or 6 wk.The reduced expression of let-7a-5p can alleviate hepato-biliary injuries indicated by serum markers,and prevent the proliferation of cholangiocytes and biliary fibrosis.Furthermore,inhibition of let-7a mediated by rAAV8 can increase the expression of potential target molecules such as suppressor of cytokine signaling 1 and Dectin1,which consequently inhibit of NF-κB-mediated hepatic inflammation.CONCLUSION Our study demonstrates that a rAAV8 vector designed for liver-specific inhibition of let-7a-5p can potently ameliorate symptoms in a xenobiotic-induced mouse model of sclerosing cholangitis,which provides a possible clinical translation of PSC of human.

关键词： Primary sclerosing cholangitis Recombinant adeno-associated virus 8 Let-7a-5p Therapeutic effects Inflammation

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斯拉夫早期语法文献中关于同音异义问题的论争及影响

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中国俄语教学 2024年第1期43卷 1-8页

作者：尹旭北京大学

同音异义现象是人类语言无法回避的话题,长期为词典学家、语义学家所重视。斯拉夫世界对其的研究始于15—17世纪,与现代不同的是,彼时学者重点关注同音异义词对的区分,进而提出正字法中的字母置换原则,并针对置换字母(符号)对的构成、... 详细信息

同音异义现象是人类语言无法回避的话题,长期为词典学家、语义学家所重视。斯拉夫世界对其的研究始于15—17世纪,与现代不同的是,彼时学者重点关注同音异义词对的区分,进而提出正字法中的字母置换原则,并针对置换字母(符号)对的构成、应用对象、使用位置等多个议题进行了长期的论争,最终以斯莫特利茨基语法中的实施原则为蓝本构建了现代教会斯拉夫语的规范正字法体系。不过随着新的大罗斯民族语言的形成,该原则在延续了标准语传统的俄语中仅保留了部分残迹。

关键词：同音异义现象字母置换原则古代俄语现代俄语

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The impact of female sex hormones on cardiovascular disease:from mechanisms to hormone therapy

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Journal of Geriatric Cardiology 2024年第6期21卷 669-681页

作者： Yi KAN Yu-Lu PENG Ze-Hao ZHAO Shu-Tong DONG yin-Xiao xu Xiao-Teng MA Xiao-Li LIU Yu-Yang LIU Yu-Jie ZHOU Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijing Institute of Heart Lung and Blood Vessel DiseaseBeijing Key Laboratory of Precision Medicine of Coronary Atherosclerotic DiseaseClinical Center for Coronary Heart DiseaseCapital Medical UniversityBeijingChina

Cardiovascular disease remains the leading cause of mortality in women,yet it has not raised the awareness from the public.The pathogenesis of cardiovascular disease differs significantly between females and males concerning the effect of sex hormones.Estrogen and progestogen impact cardiovascular system through genomic and non-genomic effects.Before menopause,cardiovascular protective effects of estrogens have been well described.Progestogens were often used in combination with estrogens in hormone therapy.Fluctuations in sex hormone levels,particularly estrogen deficiency,were considered the specific risk factor in women’s cardiovascular disease.However,considerable heterogeneity in the impact of hormone therapy was observed in clinical trials.The heterogeneity is likely closely associated with factors such as the initial time,administration route,dosage,and formulation of hormone therapy.This review will delve into the pathogenesis and hormone therapy,summarizing the effect of female sex hormones on hypertension,pre-eclampsia,coronary heart disease,heart failure with preserved ejection fraction,and cardiovascular risk factors specific to women.

关键词： impact dosage protective

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考虑多车影响的智能网联车跟驰模型

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吉林大学学报（工学版） 2024年第5期54卷 1285-1292页

作者：蒲云徐银刘海旭谭一帆西南交通大学交通运输与物流学院成都610031 西南交通大学综合交通大数据应用技术国家工程实验室成都611756 西南交通大学综合交通运输智能化国家地方联合工程实验室成都610031 威斯康星大学麦迪逊分校土木与环境工程系威斯康星州麦迪逊53706

为研究智能网联车(CAV)对交通流的影响,基于智能驾驶人模型(IDM),考虑后车和多前车速度差的影响,构建CAV智能驾驶跟驰模型,推导了CAV跟驰模型的临界稳定性条件。然后以考虑1辆后车和5辆前车速度差的CAV跟驰模型设计数值仿真实验。结果表... 详细信息

为研究智能网联车(CAV)对交通流的影响,基于智能驾驶人模型(IDM),考虑后车和多前车速度差的影响,构建CAV智能驾驶跟驰模型,推导了CAV跟驰模型的临界稳定性条件。然后以考虑1辆后车和5辆前车速度差的CAV跟驰模型设计数值仿真实验。结果表明:交通流稳定性随考虑后车影响的权重比例变化而变化,即只有当后视权重比例在恰当范围内时才可提高交通流稳定性;考虑后车影响和多前车速度差还可削弱由时延导致的交通流不稳定性。同时,新模型控制下的车辆加速度变化更平稳,更有助于提高交通流稳定性和交通流安全性。

关键词：交通工程跟驰模型智能网联车交通流稳定性安全性评价

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面向构网逆变器的虚拟振荡器控制技术:统一设计框架与关键问题探讨

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电网技术 2024年第6期48卷 2251-2261,I0003,I0004页

作者：史亚帆许寅吴翔宇时珊珊北京交通大学电气工程学院北京市海淀区100044 北京市轨道交通电气工程技术研究中心北京市海淀区100044 国网上海市电力公司电力科学研究院上海市虹口区200437

虚拟振荡器控制是近年来新兴的逆变器构网型控制方式,相较于下垂控制、虚拟同步发电机控制等现有构网型控制而言,其在动态响应速度与大扰动稳定性等方面具有优势。首先基于已有研究介绍了虚拟振荡器控制的基本原理及现有类型,接着针对... 详细信息

虚拟振荡器控制是近年来新兴的逆变器构网型控制方式,相较于下垂控制、虚拟同步发电机控制等现有构网型控制而言,其在动态响应速度与大扰动稳定性等方面具有优势。首先基于已有研究介绍了虚拟振荡器控制的基本原理及现有类型,接着针对虚拟振荡器设计目前缺乏普适性的问题提出了虚拟振荡器控制的统一设计框架及详细设计步骤,并以自行设计的两类虚拟振荡器为例,通过时域仿真验证了所提设计框架的可行性;最后从功率调度能力、抗扰动稳定运行能力以及实际应用能力3方面针对目前限制虚拟振荡器控制技术发展的关键问题进行了梳理与探讨,并给出了解决思路与未来的研究方向。

关键词：虚拟振荡器构网逆变器逆变器控制稳定性统一设计框架

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居民消费结构升级对企业全要素生产率的影响研究

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经济学家 2024年第2期 101-110页

作者：王钰殷诗絮首都经济贸易大学经济学院

中国全面建成小康社会后进入共同富裕的新发展阶段,居民消费结构升级是必然趋势。本文基于2014—2020年中国上市企业的面板数据,分析消费结构升级对企业全要素生产率影响的微观机制。研究结果发现:居民消费结构升级对促进企业全要素生... 详细信息

中国全面建成小康社会后进入共同富裕的新发展阶段,居民消费结构升级是必然趋势。本文基于2014—2020年中国上市企业的面板数据,分析消费结构升级对企业全要素生产率影响的微观机制。研究结果发现:居民消费结构升级对促进企业全要素生产率提升具有显著的正向作用,消费结构升级通过供给端和需求端两侧分别对企业的创新活动和创新要素产生影响,进而影响企业全要素生产率。进一步研究发现,在经济结构服务化下,消费结构升级对企业全要素生产率提升的正向作用是“边际效应减弱”的;消费结构升级对企业全要素生产率提升的促进作用在行业与企业两个层面具有异质性。为此,应将供给和需求两侧协调配合,一方面采取措施恢复、稳定和扩大内需;另一方面支持企业进行创新投入,参与创新活动,培育企业的创新能力。

关键词：消费结构升级企业创新企业全要素生产率结构转型

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核受体PPARγ在溃疡性结肠炎中的作用及中医药干预研究进展

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中国实验方剂学杂志 2024年第8期30卷 233-244页

作者：张伟邹孟龙徐寅朱莹湖南中医药大学第一中医临床学院长沙410208 湖南中医药大学第一附属医院长沙410007

溃疡性结肠炎(UC)是一种主要累及结肠和直肠的慢性炎症性肠病,以腹痛、血性腹泻和里急后重感为典型症状,病理机制尚未完全阐明。该病反复发作,严重影响患者生活质量,而常用的治疗药物具有临床疗效欠佳、疗程长、不良反应多等局限,故亟... 详细信息

溃疡性结肠炎(UC)是一种主要累及结肠和直肠的慢性炎症性肠病,以腹痛、血性腹泻和里急后重感为典型症状,病理机制尚未完全阐明。该病反复发作,严重影响患者生活质量,而常用的治疗药物具有临床疗效欠佳、疗程长、不良反应多等局限,故亟需寻找新的治疗药物。过氧化物酶体增殖物激活受体γ(PPARγ)是一种配体依赖性核受体蛋白,在维持肠道稳态中发挥了重要作用,并与UC的发生发展密切相关。中医药治疗UC具有多靶点、不良反应小等优势,近年大量研究发现中医药可以通过调控核受体PPARγ发挥治疗UC的作用。结果表明PPARγ是中医药治疗UC的重要靶点,中医药多采用清热燥湿、行气活血化瘀、健脾温肾和攻补兼施之法干预PPARγ,一方面直接激活PPARγ,或通过介导核转录因子-κB(NF-κB)、丝裂原活化蛋白激酶(MAPK)、Toll样受体4(TLR4)等信号通路、调节辅助性T细胞17(Th17)/调节性T细胞(Treg)平衡、促进巨噬细胞由促炎M1型向抗炎M2型极化等方式控制促炎因子与抗炎因子水平,从而抑制肠道炎症反应;另一方面通过调节肠道代谢,激活PPARγ,降低硝酸盐水平并维持局部缺氧状态,从而调节专性厌氧菌与兼性厌氧菌平衡,改善肠道微生态,最终起到防治UC的作用。该文将核受体PPARγ在UC中的作用及近5年中医药通过干预PPARγ治疗UC的研究进展进行梳理和总结,旨在为UC的治疗及新药研发提供思路。

关键词：过氧化物酶体增殖物激活受体γ(PPARγ) 溃疡性结肠炎核转录因子-κB(NF-κB) 丝裂原活化蛋白激酶(MAPK) Toll样受体4(TLR4) 中医药

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