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Dynamic response and failure process of horizontal-layered fractured structure rock slope under strong earthquake

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Journal of Mountain Science 2024年第3期21卷 882-900页

作者： WANG Tong LIU Xianfeng HOU Zhaoxu XU jiahang ZHANG Jun YUAN Shengyang JIANG Guanlu HU Jinshan School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of High-Speed Railway Engineering of Ministry of Education Southwest Jiaotong UniversityChengdu 610031China School of Civil Engineering Xinjiang Institute of EngineeringUrumqi 830023China China Railway First Survey and Design Institute Group Co.LTD Xi'an 710043China

Rock slope with horizontal-layered fractured structure(HLFS)has high stability in its natural state.However,a strong earthquake can induce rock fissure expansion,ultimately leading to slope failure.In this study,the dynamic response,failure mode,and spectral characteristics of rock slope with HLFS under strong earthquake conditions were investigated based on the large-scale shaking table model test.On this basis,multiple sets of numerical calculation models were further established by UDEC discrete element program.Five influencing factors were considered in the parametric study of numerical simulations,including slope height,slope angle,bedding-plane spacing and secondary joint spacing as well as bedrock dip angle.The results showed that the failure process of rock slope with HLFS under earthquake action is mainly divided into four phases,i.e.,the tensile crack of the slope shoulder joints and shear dislocation at the top bedding plane,the extension of vertical joint cracks and increase of shear displacement,the formation of step-through sliding surfaces and the instability,and finally collapse of fractured rock mass.The acceleration response of slopes exhibits elevation amplification effect and surface effect.Numerical simulations indicate that the seismic stability of slopes with HLFS exhibits a negative correlation with slope height and angle,but a positive correlation with bedding-plane spacing,joint spacing,and bedrock dip angle.The results of this study can provide a reference for seismic stability evaluation of weathered rock slopes.

关键词： Seismic behavior Horizontal layered Weathered rock slope Shaking table test Failure mode

¹⁸F-FES PET/CT Research Progress in the Diagnosis and Treatment of Breast Cancer

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Journal of Biosciences and Medicines 2024年第1期12卷 105-114页

作者： jiahang He Hua Pang Department of Nuclear Medicine The First Affiliated Hospital of Chongqing Medical University Chongqing China

Estrogen receptor(ER) is a vital biomarker in the development and development of breast cancer, and its status has great clinical value in clinical treatment strategy, endocrine therapy efficacy prediction, and breast cancer prognosis. By specifically combining 18F-FES with ER, 18F-FES PET/CT imaging uses standard uptake value(SUV) to semi-quantitatively reflect the distribution of ER and its biological activity in patients, and assesses the expression of ER in breast cancer patients about primary and metastases before or after treatment, to provide a basis for personalized treatment of breast cancer. In this review, we will review the imaging principles of a new ER detection method 18F-FES PET/CT, and the research progress in the clinical application of breast cancer, and compare its diagnostic and treatment value with non-specific tumor imaging 18F-FDG PET/CT in breast cancer.

关键词： 18F-FES 18F-FDG PET/CT Breast Cancer ER

A Continuous Authentication Protocol Without Trust Authority for Zero Trust Architecture

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China Communications 2022年第8期19卷 198-213页

作者： Lei Meng Daochao Huang jiahang an Xianwei Zhou Fuhong Lin School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China National Computer Network Emergency Response Technical Team/Coordination Center of China(CNCERT/CC) Beijing 100029China Shunde Graduate School of University of Science and Technology Beijing Guangdong528399China

Zero-trust security is a novel concept to cope with intricate access,which can not be handled by the conventional perimeter-based architecture anymore.The device-to-device continuous authentication protocol is one of the most crucial cornerstones,especially in the IoT scenario.In the zero-trust architecture,trust does not rely on any position,person or device.However,to the best of our knowledge,almost all existing device-to-device continuous authentication relies on a trust authority or a node to generate secret keys or secret values.This is betrayed by the principle of zero-trust architecture.In this paper,we employ the blockchain to eliminate the trusted node.One node is chosen to produce the public parameter and secret keys for two entities through the practical Byzantine fault tolerance consensus mechanism.Additionally,the devices are categorized into three folds:trusted device,suspected device and untrusted device.Only the first two can participate in authentication,and they have different lengths of security parameters and intervals to reach a better balance between security and efficiency.Then we prove the security of the initial authentication part in the eCK model and give an informal analysis of the continuous authentication part.Finally,we implement the proposed protocol on simulated devices.The result illustrates that our scheme is highly efficient,and the continuous authentication only costs around 0.1ms.

关键词： continuous authentication zero-trust architecture device-to-device blockchain IoT

MSC-derived exosomes attenuate hepatic fibrosis in primary sclerosing cholangitis through inhibition of Th17 differentiation

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Asian Journal of Pharmaceutical Sciences 2024年第1期19卷 119-134页

作者： Wenyi Chen Feiyan Lin Xudong Feng Qigu Yao Yingduo Yu Feiqiong Gao jiahang Zhou Qiaoling Pan Jian Wu Jinfeng Yang Jiong Yu Hongcui Cao Lanjuan Li State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesNational Medical Center for Infectious DiseasesThe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Jinan Microecological Biomedicine Shandong Laboratory Jinan 250117China Key Laboratory of Diagnosis and Treatment of Aging and Physic-chemical Injury Diseases of Zhejiang Province Hangzhou 310003China

Primary sclerosing cholangitis(PSC)is an autoimmune cholangiopathy characterized by chronic inflammation of the biliary epithelium and periductal fibrosis,with no curative treatment available,and liver transplantation is inevitable for end-stage patients.Human placentalmesenchymal stem cell(hpMSC)-derived exosomes have demonstrated the ability to prevent fibrosis,inhibit collagen production and possess immunomodulatory properties in autoimmune liver disease.Here,we prepared hpMSC-derived exosomes(Exo^(MSC))and further investigated the anti-fibrotic effects and detailed mechanism on PSC based on Mdr2^(−/−)mice and multicellular organoids established from PSC patients.The results showed that Exo^(MSC) ameliorated liver fibrosis in Mdr2^(−/−)mice with significant collagen reduction in the preductal area where Th17 differentiation was inhibited as demonstrated by RNAseq analysis,and the percentage of CD4+IL-17A+T cells was reduced both in Exo^(MSC)-treated Mdr2^(−/−)mice(Mdr2^(−/−)-Exo)in vivo and Exo^(MSC)-treated Th17 differentiation progressed in vitro.Furthermore,Exo^(MSC) improved the hypersecretory phenotype and intercellular interactions in the hepatic Th17 microenvironment by regulating PERK/CHOP signaling as supported by multicellular organoids.Thus,our data demonstrate the antifibrosis effect of Exo^(MSC) in PSC disease by inhibiting Th17 differentiation,and ameliorating the Th17-induced microenvironment,indicating the promising potential therapeutic role of Exo^(MSC) in liver fibrosis of PSC or Th17-related diseases.

关键词： Mesenchymal stem cell Exosomes Primary sclerosing cholangitis Fibrosis Organoids Th17

Precision Machining Equipment Fault Diagnosis Based on CWT and Improved ResNeXt

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Instrumentation 2024年第2期 36-43页

作者： Lichen Shi jiahang Guo Haitao Wang School of Mechanical and Electrical Engineering Xi'an University of Architecture and Technology Finishing Processing Laboratory Xi'an University of Architecture and Technology

A fault diagnosis method based on continuous wavelet transform and improved multi-dimensional residual network was proposed to solve the problem that the working environment of precision machining equipment is very complicated, and the fault characteristic signal is weak and hard to extract. Firstly, the best wavelet base Cmor 3-3 is selected by comparing 6 different wavelet base types. Secondly, continuous wavelet transform(CWT) is applied to the acquired original vibration signal to generate the feature map and process the gray level. Finally, the improved ResNeXt network is used to diagnose faults in precision machining equipment. The experimental results show that the proposed CWT and the improved ResNeXt algorithm have high accuracy in identifying precision machining equipment faults in complex environments, with an average accuracy of 99.4%.

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Diet restriction and exercise alleviate cognitive reduction of high fat diet(HFD)-induced obese mice by rescuing inflammation-mediated compromised insulin signaling pathway through activating AMPK/SIRT1 signal pathway and suppressing TLR4 signal pathway

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Food Science and Human Wellness 2024年

作者： Hu Zhang Ye Zhang Jiling Liang jiahang Li Miao He Xin Liu Jielun Huang Minghui Wang Jingjing Fan Ning Chen Tianjiu Research and Development Center for Exercise Nutrition and Foods Hubei Key Laboratory of Exercise Training and Monitoring College of Sports Medicine Wuhan Sports University Physical Education Institute Hubei University of Science and Technology

Obesity， caused by excessive energy， leads to body weight gain and various diseases， including cognitive impairment. Current studies suggest that diet restriction such as optimal fasting and regular exercise are crucial for improving cognitive capacity. However， further exploration is needed to understand the specific mechanisms of high fat diet (HFD)-induced cognitive decline in obesity. In the present study， 4-month-old mice were subjected to HFD feeding for 18 weeks， followed by aerobic exercise and high-intensity intermittent exercise， regular diet feeding， and intermittent fasting for 8 weeks， and then used to evaluate cognitive capacity， inflammation， compromised insulin signaling pathway， oxidative stress， and apoptosis in hippocampal tissue， as well as AMPK/SIRT1 and TLR4 signal pathways. Obese mice revealed impaired cognitive capacity as compared with mice fed with regular diets. In contrast， aerobic exercise， high-intensity intermittent exercise， regular diet， and intermittent fasting could inhibit apoptosis caused by inflammation-mediated compromised insulin signaling pathway in hippocampal tissues through activating the AMPK/SIRT1 signal pathway and suppressing the TLR4 signal pathway， thereby rescuing the cognitive impairment of obese mice. Therefore， diet restriction and exercise interventions may play a positive role in reverting obesity-induced cognitive impairment.

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“生产-生活-生态”视角下国民幸福感的影响因素与形成机制

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资源科学 2024年第5期46卷 910-923页

作者：刘嘉航尹春孙斌栋华东师范大学中国行政区划中心上海200241 华东师范大学未来城市实验室上海200241 武汉大学资源与环境科学学院武汉430079 武汉大学空间全生命周期健康国际研究中心武汉430079

[目的]通过分析国民幸福感的影响因素与形成机制,为各国政府制定针对性的国民幸福感提升策略提供参考依据。[方法]本文基于人类所依托的生产、生活、生态空间,从“三生”视角提出了国民幸福感分析框架,通过收集2005-2018年146个国家的... 详细信息

[目的]通过分析国民幸福感的影响因素与形成机制,为各国政府制定针对性的国民幸福感提升策略提供参考依据。[方法]本文基于人类所依托的生产、生活、生态空间,从“三生”视角提出了国民幸福感分析框架,通过收集2005-2018年146个国家的国民幸福感汇总数据,在展示国民幸福感全球时空格局的基础上,使用双向固定效应模型和因果逐步检验方法分析了“三生”因素对国民幸福感的影响及其机制。[结果](1)国民幸福感呈现以欧洲北部、美洲北部和大洋洲为“高地”的三极分布特征,亚洲西部和南部以及非洲是其中的“洼地”;同时具有多元分化的趋势,且各大洲内部均存在明显差异。(2)生产因素中的收入基尼系数和生活因素中的失业率的增加导致了国民幸福感的下降,提高生活因素中的社会支持程度和生态因素中的人均国土绿化面积有利于提升国民幸福感。GDP增长率和收入基尼系数等生产因素在发展中国家的影响更大。(3)积极情绪和消极情绪是“三生”因素影响国民幸福感的中介因素。通货膨胀率、失业率、受教育年限和碳排放强度通过情绪变量与国民幸福感存在负向关联,社会支持程度、政府治理能力、少年人口抚养比和人均国土绿化面积对国民幸福感具有间接的正向影响。[结论]因此,中国需要坚持“生产发展、生活富裕、生态良好”的发展道路,有利于最大化国民福祉。

关键词：国民幸福感 “三生”因素积极情绪消极情绪形成机制

嵌入、混合与协同:“运营”与算法的人机协作实践

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现代出版 2024年第4期 61-72页

作者：王佳航李潇中国政法大学光明新闻传播学院

平台成为社会基础设施,政、商、媒体等多种主体加入到内容生产系统。基于此,承载内容、情感、关系、政治沟通、亚文化展演等多重功能的内容生产网络不仅是内容生产与传播的生态系统,也是社会结构的展演。算法嵌入内容生产网络,人机协同... 详细信息

平台成为社会基础设施,政、商、媒体等多种主体加入到内容生产系统。基于此,承载内容、情感、关系、政治沟通、亚文化展演等多重功能的内容生产网络不仅是内容生产与传播的生态系统,也是社会结构的展演。算法嵌入内容生产网络,人机协同的内容分发机制带来效率和风险,也使得人机关系议题呈现出复杂性。采用参与式观察和深度访谈法,对平台内和平台外的内容生产实践进行研究剖析发现,“运营”与智能算法形成了新型人机协作关系。一方面,平台社会的内容生产网络是人机混合的内容生产网络,在这一网络中人和算法互相驯化。另一方面,智能算法嵌入内容生产网络,即嵌入深层社会结构之中,智能算法维护社会网,并对社会网产生影响。

关键词：嵌入运营人机协同

基于Citespace软件可视化兮析的我国城市轨道交通车辆发展研究

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城市轨道交通研究 2024年第6期27卷 178-184页

作者：周嘉行王嘉鑫中车浦镇阿尔斯通运输系统有限公司芜湖241060

[目的]为了解我国近20年来城市轨道交通车辆发展研究情况,利用Citespace软件对我国近20年来城市轨道交通车辆相关文献进行可视化检索分析,并厘定前沿热点。[方法]在CNKI(中国知网)论文数据库中,将检索范围选择期刊,出版年度选取2001年—... 详细信息

[目的]为了解我国近20年来城市轨道交通车辆发展研究情况,利用Citespace软件对我国近20年来城市轨道交通车辆相关文献进行可视化检索分析,并厘定前沿热点。[方法]在CNKI(中国知网)论文数据库中,将检索范围选择期刊,出版年度选取2001年—2020年,将检索条件设为“主题‘车辆’+全文‘城市轨道交通’”,获文献9392篇,以Refworks的格式导出,经Citespace软件筛选、去重后生成新的数据,研究包括文献数量及时间特征、关键词、被引频次、研究机构合作关系、研究热点以及前沿分析等内容。[结果及结论]研究节点以2008年和2016年为界,分为稳步增长、快速增长、指数式增长3个阶段;研究热点主要集中于“牵引”“制动”“动力学”和“转向架”等;研究前沿为“超级电容”“市域铁路”“车辆检修”等;相关学者和研究机构主要集中在高校和主机厂等。

关键词：城市轨道交通车辆 Citespace 知识图谱