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Is there a great unconformity between Xiamaling and Longshan formations in the North China Craton?

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Science China Earth Sciences 2023年第5期66卷 959-984页

作者： Hongwei KUANG Nan PENG yongqing liu Yuchong WANG Mingming CUI Xiaoshuai CHEN Dawei QIAO Keining QI Institute of Geology Chinese Academy of Geological SciencesBeijing100037China School of Earth Science and Mapping Engineering China University of Mining and Technology(Beijing)Beijing100083China School of Resource and Environmental Engineering Hefei University of TechnologyHefei230009China

The existence of a 0.3 Ga"great unconformity"between the Mesoproterozoic"Undefined System"Xiamaling Formation and the"Neoproterozoic"Longshan Formation has long been controversial.In this study,stratigraphy,sedimentology,detrital zircon dating,lithium isotope,and major and trace elements were applied to systematically analyze their relationship.Results demonstrate that coarse to fine sandstone-mudstone normal cycles with different grades and thicknesses exist from the Xiamaling to the Longshan formations.Sedimentary succession formed from a restricted platform with lagoon-shallow marine shelf-tidal flat-beach and tidal shoal developing in ascending order.The pebbly sandstone at the bottom of the Long shan Formation does not have the properties of basal conglomerate with tectonic significance.The youngest detrital zircon is older than 1.6 Ga for the Long shan Formation and overlying Jing'eryu Formation sandstones.In addition,no(zircon)provenance has been found from the large igneous province of 1.32-1.2 Ga in Xiamaling Formation.Theδ^(7)Li isotope values exhibit a gradually increasing trend.The Li content and CIA(Chemical index of alteration)gradually decreases from the top of the Xiamaling Formation to the lower part of the Long shan Formation.Simultaneously,as K_(2)O/Al_(2)O_(3)and FeO/Fe_(2)O_(3)decreases,Na_(2)O/Al_(2)O_(3)increases,and Li/Al,V/Cr,and V/(V+Ni)fluctuates slightly.At the boundary,the Ce/Ce^(*)and Eu/Eu^(*)show positive and negative anomalies,respectively.Further,the Rb/Sr and Al/Si values decrease,and U/Th values increase.This indicates that the geochemistry of the weathering crust at the interface of the Xiamaling Formation-Long shan Formation is not characteristic.However,it indicates a weakening of continental weathering intensity from the bottom to the top of the interface.These results do not support the existence of a large unconformity between the Xiamaling and the Longshan formations.Therefore,it is suggested that the Long shan Formation-Jing'eryu Formation should be moved to the lower l

关键词： North China Craton Mesoproterozoic Transition period Unconformity Continuous sedimentation

Transcriptional Analysis of Normal Human Fibroblast Responses to Microgravity Stress

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Genomics, Proteomics & Bioinformatics 2008年第1期6卷 29-41页

作者： yongqing liu Eugenia Wang Department of Biochemistry and Molecular Biology University of Louisville School of Medicine Louisville KY 40202 USA. Current address. James Graham Brown Cancer Center Department of Ophthalmology and Visual SciencesUniversity of Louisville School of Medicine Louisville KY 40202 USA.

To understand the molecular mechanism（s） of how spaceflight affects cellular signaling pathways, quiescent normal human WI-38 fibroblasts were flown on the STS-93 space shuttle mission. Subsequently, RNA samples from the spaceflown and ground-control cells were used to construct two cDNA libraries, which were then processed for suppression subtractive hybridization （SSH） to identify spaceflight-specific gene expression. The SSH data show that key genes related to oxidative stress, DNA repair, and fatty acid oxidation are activated by spaceflight, suggesting the induction of cellular oxidative stress. This is further substantiated by the up-regulation of neuregulin 1 and the calcium-binding protein calmodulin 2. Another obvious stress sign is that spaceflight evokes the Ras/mitogen-activated protein kinase and phosphatidylinositol-3 kinase signaling pathways, along with up-regulating several Gl-phase cell cycle traverse genes. Other genes showing upregulation of expression are involved in protein synthesis and pro-apoptosis, as well as pro-survival. Interactome analysis of functionally related genes shows that c-Myc is the ＂hub＂ for those genes showing significant changes. Hence, our results suggest that microgravity travel may impact changes in gene expression mostly associated with cellular stress signaling, directing cells to either apoptotic death or premature senescence.

关键词： microgravity apoptosis premature senescence oxidative stress subtractive hybridization

Cell-based therapies for age-related macular degeneration:cell replacement versus paracrine effects

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Neural Regeneration Research 2021年第6期16卷 1214-1215页

作者： Xiaoyan Peng Ling Gao yongqing liu Department of Ophthalmology Beijing Tongren HospitalCapital Medical UniversityBeijingChina Department of Ophthalmology Second Affiliated Hospital of Xiangya Medical SchoolCentral South China UniversityChangshaHunan ProvinceChina James Graham Brown Cancer Center Department of Ophthalmology and Visual SciencesBirth Defects CenterUniversity of Louisville School of MedicineLouisvilleKYUSA

Age-related macular degeneration(AMD)is a leading cause for severe visual loss and legal blindness in seniors worldwide.The molecular basis for the disease remains poorly understood,likely involving genetic and environment-related ocular defects.Its pathogenesis proceeds slowly,started with deposits of fatty proteins(drusen)in the Bruch’s membrane,followed by gradual impairments of the posterior choriocapillaris and the anterior retinal pigment epithelium(RPE),and lead to irreversible degeneration of the light receiving neurons(photoreceptor)and vision decline.Clinically,AMD is divided into two subgroups:dry or atrophy form and wet or exudative form.Twenty percent of AMD patients have the wet form.

关键词： degeneration legal irreversible

Almost periodic solution to singular systems

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Chinese Science Bulletin 1998年第8期43卷 698-700页

作者： Jiarong Liang yongqing liu Cunchen Gao S China Univ Technol Dept Automat Canton 510641 Peoples R China

The problems about the almost periodic solution to singular systems are studied. The criterion that the singular systems have almost periodic solutions is obtained. At the same time, the applied example is given.

关键词： singular systems almost periodic solutions boundary.

The uplifting process of the Bogda Mountain during the Cenozoic and its tectonic implication

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Science China Earth Sciences 2008年第4期51卷 579-593页

作者： ZongXiu Wang Tao Li Jin Zhang yongqing liu ZongJin Ma Institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China Institute of Geology China Seismological Administration Beijing 100029 China Institute of Geology Chinese Academy of Geological Sciences Beijing 1

The Tianshan Mountains have undergone its initial orogeny, extension adjusting and re-orogeny since the Late Paleozoic. The re-orogeny and uplifting process of the orogeny in the Mesozoic and Cenozoic are two of most important events in the geological evolution of Euro-Asian continent, which resulted in the formation of the present range-and-basin pattern in topography of the Tianshan Mountains and its adjacent areas. Thermochronology results by the method of fission-track dating of apatite suggest three obvious uplifting stages of the Bogad Mountain Chain re-orogeny during the Cenozoic, i.e. 5.6-19 Ma, 20-30 Ma, and 42-47 Ma. The strongest uplifting stage of the mountain is the second one at 20 -30 Ma, when the mountain uplifted as a whole, and the beginning of re-orogeny was no less than 65 Ma. Furthermore, our studies also show that the uplifting types of the mountain are variable in the dif-ferent time periods, including uplifting of mountain as a whole and differential uplifting. The apparently diversified uplifting processes of the mountain chain are characterized by the migration (or transfor-mation) of the uplifting direction of the mountain from west to east and from north to south, and the main process of mountain extending is from north to south.

关键词： Bogda Mountain Chain re-orogeny uplifting thermochronology fission track

基于演化博弈的电子废弃物回收产业链协同治理

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湖南科技大学学报（自然科学版） 2024年第1期39卷 104-114页

作者：刘永清刘文浩陈爱妩湖南科技大学商学院湖南湘潭411201

电子废弃物回收产业链的发展需要多方利益相关者的协同参与.从协同治理视角出发,分别构建市场机制下和政府调控下的“回收企业—生产企业”演化博弈模型,通过复制动态方程得到博弈双方的稳定策略演化路径.研究表明:单一主体的收益最大... 详细信息

电子废弃物回收产业链的发展需要多方利益相关者的协同参与.从协同治理视角出发,分别构建市场机制下和政府调控下的“回收企业—生产企业”演化博弈模型,通过复制动态方程得到博弈双方的稳定策略演化路径.研究表明:单一主体的收益最大化未必有利于产业的形成和回收产业效益的最大化;博弈双方会基于自身成本收益禀赋和策略带来的增值量进行反复博弈,从而使博弈系统形成不同的演化路径;在市场机制下,博弈系统趋于理想化均衡状态的条件较难得到满足,政府调控可以快速地引导博弈系统向理想状态演化,提升监管效率、加大补贴和对投机行为的惩罚力度能够促进回收产业链的良性发展.

关键词：电子废弃物回收产业链协同治理演化博弈

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大口径热不敏星敏感器光机设计与分析

红外技术 2024年第1期46卷 31-35页

作者：刘永清高天元韩旭长春理工大学光电工程学院吉林长春130022

为满足大口径长焦距星敏感器的需求,对一种大口径热不敏星敏感器进行光机设计,根据指标要求,对热不敏系统进行光机热集成分析。使用MSC.Patran软件对主次镜结构施加温度载荷,计算出主次镜结构的热弹性变形,先利用MSC.Nastran软件计算热... 详细信息

为满足大口径长焦距星敏感器的需求,对一种大口径热不敏星敏感器进行光机设计,根据指标要求,对热不敏系统进行光机热集成分析。使用MSC.Patran软件对主次镜结构施加温度载荷,计算出主次镜结构的热弹性变形,先利用MSC.Nastran软件计算热变形后节点的刚体位移,再利用Sigft光机接口软件分析得到变形后主次镜表面的Zernike多项式系数。将结果导入Zemax中,预判镜片面型变化以及刚体位移对弥散斑、光轴漂移量及波像差的影响。最后通过在20℃±5℃的温度范围内装调测试验证了系统性能满足指标要求以及光机热集成分析的准确性,提供了一套准确快捷的光机热集成分析流程。

关键词：星敏感器光机设计弥散斑光机热集成分析

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煤矿掘进机液压系统常见故障及原因分析

能源与节能 2024年第6期 222-224页

作者：刘永庆山西介休义棠倡源煤业有限公司山西介休032000

煤矿掘进机是巷道机械化掘进的主要设备,其核心部分是液压系统。由于煤矿井下恶劣的作业环境,掘进机液压系统经常会发生故障,对于煤矿的高效掘进十分不利。为了保证掘进机的高效运行,必须充分了解液压系统常见的故障及原因。首先,分析... 详细信息

煤矿掘进机是巷道机械化掘进的主要设备,其核心部分是液压系统。由于煤矿井下恶劣的作业环境,掘进机液压系统经常会发生故障,对于煤矿的高效掘进十分不利。为了保证掘进机的高效运行,必须充分了解液压系统常见的故障及原因。首先,分析了掘进机液压系统典型的故障,主要有漏油、动力不足、噪声过大等;然后,重点探讨了发生故障的原因,以期为掘进机的维修提供一定的参考。

关键词：煤矿开采掘进机液压系统故障故障原因

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奎宁酸的抗氧化活性和神经保护作用研究

食品与发酵工业 2024年第5期50卷 42-47页

作者：王硕梁婷罗磊刘永清方勇李森管骁上海理工大学健康科学与工程学院上海200093 国家粮食产业(城市粮油保障)技术创新中心上海200093 南京财经大学食品科学与工程学院江苏南京210023

奎宁酸是一种小米来源的类黄酮类物质,为探究奎宁酸的神经保护作用,该研究建立了H_(2)O_(2)诱导的SH-SY5Y细胞氧化应激模型,通过MTT法测定奎宁酸对SH-SY5Y细胞活性影响,同时测定了抗氧化酶超氧化物歧化酶(superoxide dismutase,SOD)的... 详细信息

奎宁酸是一种小米来源的类黄酮类物质,为探究奎宁酸的神经保护作用,该研究建立了H_(2)O_(2)诱导的SH-SY5Y细胞氧化应激模型,通过MTT法测定奎宁酸对SH-SY5Y细胞活性影响,同时测定了抗氧化酶超氧化物歧化酶(superoxide dismutase,SOD)的活性和氧化应激标志分子谷胱甘肽(glutathione,GSH)、丙二醛(malondialdehyde,MDA)的含量,利用实时荧光定量PCR检测了抗氧化酶和炎症因子表达情况,并用Western blot测定了炎症因子的蛋白表达量。研究结果表明,100μg/mL的奎宁酸处理显著抑制H_(2)O_(2)引起的SH-SY5Y细胞存活率下降;对细胞抗氧化指标的检测显示,奎宁酸处理可以增强细胞SOD的活性,增加GSH的水平并降低细胞的MDA水平,提高SOD、过氧化氢酶(catalase,CAT)、谷胱甘肽过氧化物酶(glutathione peroxidase,GPx)等抗氧化酶基因的表达水平,降低氧化损伤;另外,奎宁酸还可以降低H_(2)O_(2)诱导的SH-SY5Y细胞中炎症因子白介素-1β(IL-1β)和肿瘤坏死因子-α(TNF-α)的表达水平,减轻SH-SY5Y细胞的损伤。综上,奎宁酸可以通过抑制细胞氧化应激水平、发挥抗炎作用保护神经细胞不被损伤,为进一步探究小米多酚在氧化应激相关疾病中的作用奠定了基础。

关键词： SH-SY5Y细胞奎宁酸氧化应激抗炎作用抗氧化作用