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Monazite U-Th-Pb and sericite Rb-Sr dating of the Xiajiadian black shale-hosted gold deposit in the Qinling orogen, central China: Implications for regional gold metallogeny

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Science China Earth Sciences 2024年第8期67卷 2478-2494页

作者： Xueling YU Jianwei li Xiaoye JIN Shaorui ZHAO Chongguo HE yunlong ZHU State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences School of Earth Resources China University of Geosciences

The Qinling orogen in central China contains several black shale-hosted gold deposits, but the age of their formation and a possible relation between gold mineralization and regional tectonism remain undetermined. Here we present results of in situ monazite U-Th-Pb dating and sericite Rb-Sr dating of the Xiajiadian black shale-hosted gold deposit to provide tight constraints on the time of gold deposition and information on the tectonic setting under which the deposit formed. The Xiajiadian gold deposit is mainly hosted in black shales of the Lower Cambrian Shuigoukou formation, with minor ores contained in sandy conglomerate of the Lower Devonian Xichahe formation. Gold ores in the black shales have been intensively oxidized and consist mainly of hematite, goethite, gypsum, quartz, calcite, native gold, and unrecognized iron oxides. However, gold ores in the sandy conglomerate are free of oxidation and thus provide an opportunity to date the formation of the Xiajiadian gold deposit.The ores consist of pyrite, marcasite, sericite, and quartz, which are associated with a variety of accessory minerals, including monazite, apatite, and titanite. Gold is mainly present as structure-bound ions or nanoparticles in pyrite and marcasite, but minor native gold grains also occur as inclusions in pyrite. Monazite is well developed in the ores, and has close textural association with Au-bearing pyrite and marcasite. Most monazite grains have zoned textures consisting of a core area（Mnz1） and an overgrowth zone（Mnz2）. Mnz1 contains 4.8–13 wt.% ThO2and shows large variations in HREE and prominent negative Eu anomalies in the chondrite-normalized REE patterns. It yields common lead-corrected208Pb/232Th dates ranging from 910±10 to416±4 Ma（2σ）. These dates are interpreted in terms of a detrital origin for monazite in the core area. Mnz2 has much lower ThO2contents of 0.8–1.7 wt.% and shows weak negative Eu anomalies in the chondrite-normalized REE patterns. It yields common lead-corrected208Pb/232Th dates of 229–209 Ma（2σ） with

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Multidimensional autophagy nano-regulator boosts Alzheimer's disease treatment by improving both extra/intraneuronal homeostasis

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1380-1399页

作者： Yixian li Peng Yang Ran Meng Shuting Xu lingling Zhou Kang Qian Pengzhen Wang yunlong Cheng Dongyu Sheng Minjun Xu Tianying Wang Jing Wu Jinxu Cao Qizhi Zhang Key Laboratory of Smart Drug Delivery Ministry of EducationSchool of PharmacyFudan UniversityShanghai 201203China

Intraneuronal dysproteostasis and extraneuronal microenvironmental abnormalities in Alzheimer’s disease(AD)collectively culminate in neuronal deterioration.In the context of AD,autophagy dysfunction,a multi-link obstacle involving autophagy downregulation and lysosome defects in neurons/microglia is highly implicated in intra/extraneuronal pathological processes.Therefore,multidimensional autophagy regulation strategies co-manipulating“autophagy induction”and“lysosome degradation”in dual targets(neuron and microglia)are more reliable for AD treatment.Accordingly,we designed an RP-1 peptide-modified reactive oxygen species(ROS)-responsive micelles(RT-NM)loading rapamycin or gypenoside XVII.Guided by RP-1 peptide,the ligand of receptor for advanced glycation end products(RAGE),RT-NM efficiently targeted neurons and microglia in AD-affected region.This nanocombination therapy activated the whole autophagy-lysosome pathway by autophagy induction(rapamycin)and lysosome improvement(gypenoside XVII),thus enhancing autophagic degradation of neurotoxic aggregates and inflammasomes,and promoting Aβ phagocytosis.Resultantly,it decreased aberrant protein burden,alleviated neuroinflammation,and eventually ameliorated memory defects in 3×Tg-AD transgenic mice.Our research developed a multidimensional autophagy nano-regulator to boost the efficacy of autophagy-centered AD therapy.

关键词： Autophagy-lysosome pathway Alzheimer’s disease Proteostasis Neuroinflammation Multi-target therapy Rapamycin Gypenoside XVII Cascade dual-targeting

钢管基材表面熔结环氧涂层附着力的评价方法及影响因素

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腐蚀与防护 2022年第4期43卷 59-64页

作者：谢挺李云龙海隆管道工程技术服务有限公司上海200949

介绍了熔结环氧涂层在钢制管道上的制备流程,分析讨论了碳钢表面熔结环氧涂层附着力的评价方法,及影响附着力的多种因素。结果表明:熔结环氧粉末材料在金属碳钢基材上有优良附着力和防碳钢基材腐蚀的性能,这可以归因于熔结环氧粉末材料... 详细信息

介绍了熔结环氧涂层在钢制管道上的制备流程,分析讨论了碳钢表面熔结环氧涂层附着力的评价方法,及影响附着力的多种因素。结果表明:熔结环氧粉末材料在金属碳钢基材上有优良附着力和防碳钢基材腐蚀的性能,这可以归因于熔结环氧粉末材料本身的结构。

关键词：化工材料熔结环氧粉末(FBE) 防腐蚀防腐蚀涂层

原儿茶酸通过Toll样受体4/核因子κB途径减轻高脂饮食诱导的肝脏炎症

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食品科学 2023年第9期44卷 72-81页

作者：焦小文李佳李云龙韩林王敏西北农林科技大学食品科学与工程学院陕西杨凌712100 山西农业大学山西功能食品研究所山西太原030031

原儿茶酸(protocatechuic acid,PCA)是花青素在体内的主要代谢产物之一,具有良好的抗炎活性。本实验利用高脂饮食(high fat diet,HFD)诱导C57BL/6J小鼠肝脏炎症,通过灌胃100 mg/(kg mb·d)PCA研究其对小鼠肝脏的保护效果,并通过体外实... 详细信息

原儿茶酸(protocatechuic acid,PCA)是花青素在体内的主要代谢产物之一,具有良好的抗炎活性。本实验利用高脂饮食(high fat diet,HFD)诱导C57BL/6J小鼠肝脏炎症,通过灌胃100 mg/(kg mb·d)PCA研究其对小鼠肝脏的保护效果,并通过体外实验进一步研究其潜在机制。体内研究结果表明,PCA干预12周后,可显著降低HFD诱导C57BL/6J小鼠的体质量和肝脏脂肪含量;血清和肝脏中白细胞介素(interleukin,IL)-1β、IL-6、肿瘤坏死因子α(tumor necrosis factorα,TNF-α)和脂多糖(lipopolysaccharide,LPS)等炎症因子水平均明显降低。体外转录组测序及原代肝细胞和肝脏的免疫印迹分析结果表明,PCA可显著降低Toll样受体4(Toll like receptor 4,TLR4)基因和蛋白的表达,然后通过下调核因子κB(nuclear factorκB,NF-κB)的磷酸化抑制炎症因子(如IL-6)的表达。综上,PCA可有效改善HFD诱导的肝脏炎症,其可能是通过下调TLR4/NF-κB信号通路来实现。

关键词：原儿茶酸肝脏炎症转录组测序 Toll样受体4 核因子κB

Magnetism in Mn and Co doped ZnO bulk samples

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Chinese Science Bulletin 2007年第8期52卷 1019-1023页

作者： WANG YongQiang YUAN Songliu SONG YunXing liU li TIAN ZhaoMing li Pai ZHOU YuanMing li yunlong YIN ShiYan Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

Bulk samples with nominal composition Zn0.95Co0.05O and Zn0.92Co0.05Mn0.03O were fabricated by a solid-state reaction method at 600℃.X-ray diffraction experiment showed that the peaks of secondary phase Co3O4 with a cubic structure were visible in both samples,besides the main peaks of wurtzite structure as ZnO.Magnetization measurement indicated that doping Co alone can induce ferromag- netism in ZnO itself,while the introduction of Mn significantly enhances ferromagnetism.However, both samples showed different magnetic behavior at temperatures below 50 K.It was also noted that ferromagnetic coupling interaction was weakened due to the presence of antiferromagnetic Co3O4.

关键词：锰钴掺杂氧化锌块磁性铁磁现象

新型双轴宽轮距跨座式单轨车辆曲线通过性分析

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重庆交通大学学报（自然科学版） 2022年第4期41卷 133-138页

作者：杜子学李云龙重庆交通大学轨道交通研究院重庆400074

新型双轴宽轮距跨座式单轨车辆转向架与现行车辆转向架结构有明显不同,表现为走行轮横向轮距大、走行轮间采用差速器结构连接,有导向轮、无稳定轮。通过对其曲线通过性的研究和分析,以确认新型转向架方案的合理性。将导向轮径向力、走... 详细信息

新型双轴宽轮距跨座式单轨车辆转向架与现行车辆转向架结构有明显不同,表现为走行轮横向轮距大、走行轮间采用差速器结构连接,有导向轮、无稳定轮。通过对其曲线通过性的研究和分析,以确认新型转向架方案的合理性。将导向轮径向力、走行轮垂向力、车体侧滚角、导向力矩、走行轮侧偏角和倾覆系数等作为车辆曲线通过性评价指标,构建了基于新型转向架结构特征的跨座式单轨车辆动力学模型,在此基础上进行了曲线通过性分析,并与现行单轨车辆曲线通过性进行了分析对比。研究结果表明:新型双轴宽轮距跨座式单轨车辆具有良好的曲线通过性,转向架结构创新有效。

关键词：车辆工程单轨车辆新型双轴宽轮距跨座式曲线通过性动力学仿真

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戊型肝炎病毒跨种间传播研究进展

临床肝胆病杂志 2023年第11期39卷 2538-2542页

作者：李云龙黄芬昆明理工大学医学院昆明650500

戊型肝炎病毒(HEV)是病毒性肝炎的病原体,可经动物跨种间传播,其感染导致的戊型肝炎发病率居世界急性病毒性肝炎的首位,现已成为危害人类健康的主要公共健康问题。近年来,越来越多的物种被鉴定成为HEV新的天然宿主,HEV跨种间传播途径越... 详细信息

戊型肝炎病毒(HEV)是病毒性肝炎的病原体,可经动物跨种间传播,其感染导致的戊型肝炎发病率居世界急性病毒性肝炎的首位,现已成为危害人类健康的主要公共健康问题。近年来,越来越多的物种被鉴定成为HEV新的天然宿主,HEV跨种间传播途径越来越多,严重阻碍了对该病毒的防控。因此,本文旨在总结、探讨HEV跨物种间传播的进展,为防控HEV的传播提供参考。

关键词：戊型肝炎病毒跨种间传播人畜共患病毒病

Direct Observation of Long Electron-Hole Diffusion Distance beyond 1 Micrometer in CH3NH3PbI3 Perovskite Thin Film

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Direct Observation of Long Electron-Hole Diffusion Distance ...

抑制整合素和黏着斑激酶促进神经干细胞对脑缺血后的神经修复

第二届新型太阳能电池学术研讨会

作者： Yu li Weibo Yan yunlong li Wei Wang Zuqiang Bian lixin Xiao Shufeng Wang Qihuang Gong Institute of Modern Optics & State Key Laboratory for Artificial Microstructure and Mesoscopic Physics School of Physics Peking University State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University

In high performance perovskite based on CHNHPbI, the formerly reported short charge diffusion distance seems a confliction to thick working layer in solar cell devices. We carried out a study on charge diffusion in spin-coated CHNHPbI perovskite thin film by transient fluorescent spectroscopy. A thickness-dependent fluorescent lifetime was found. This effect correlates to the defects at crystal grain boundaries. By coating the film with electron or hole transfer layer, PCBM or Spiro-OMe TAD respectively, we observed the charge transfer directly through the fluorescent decay. One-dimensional diffusion model was applied to obtain long charge diffusion distances, which is .3 μm for electrons and .2 μm for holes. This study gives direct support to the high performance of perovskite solar cells.

关键词： perovskite time-resolved photoluminescence charge diffusion photovoltaic solar cell

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中华老年心脑血管病杂志 2022年第8期24卷 875-878页

作者：王丽李云龙青岛市第八人民医院神经内科 266000

目的探究抑制整合素-黏着斑激酶(FAK)信号通路对脑缺血动物模型神经干细胞(NSC)移植后NSC增殖的影响。方法选择12只健康SD大鼠作为对照组,另将线栓法成功构建脑缺血模型大鼠36只。随机分为脑缺血组、NSC移植组和西仑吉肽组,每组12只。后... 详细信息

目的探究抑制整合素-黏着斑激酶(FAK)信号通路对脑缺血动物模型神经干细胞(NSC)移植后NSC增殖的影响。方法选择12只健康SD大鼠作为对照组,另将线栓法成功构建脑缺血模型大鼠36只。随机分为脑缺血组、NSC移植组和西仑吉肽组,每组12只。后2组大鼠注射10μl NSC溶液(细胞浓度为1×10^(6)个/L),西仑吉肽组还腹腔注射整合素抑制剂西仑吉肽100μg/kg。水迷宫实验分析大鼠神经功能,Western blot检测整合素和FAK蛋白表达,TUNEL染色检测神经细胞凋亡,免疫荧光染色检测NSC增殖。结果与对照组比较,脑缺血组逃避潜伏期显著升高,而穿越平台次数显著降低(P<0.05);NSC移植组逃避潜伏期显著低于脑缺血组[(34.02±4.02)s vs(48.79±4.94)s,P<0.05],而穿越平台次数显著高于脑缺血组[(4.86±0.54)次vs(2.74±0.42)次,P<0.05];西仑吉肽组逃避潜伏期显著高于NSC移植组,而穿越平台次数显著低于NSC移植组(P<0.05)。与对照组比较,脑缺血组大鼠整合素、FAK蛋白表达、凋亡指数和5溴脱氧尿嘧啶核苷(BrdU)/神经元核抗原(NeuN)阳性细胞数显著升高(P<0.05);NSC移植组整合素、FAK蛋白表达、BrdU/NeuN阳性细胞数显著高于脑缺血组,凋亡指数显著低于脑缺血组(P<0.05);西仑吉肽组整合素、FAK蛋白表达、BrdU/NeuN阳性细胞数显著低于NSC移植组,凋亡指数显著高于NSC移植组(P<0.05)。结论外源性NSC增殖、分化为神经元的过程中,整合素-FAK信号通路被激活,抑制整合素-FAK信号通路会影响NSC对脑缺血大鼠神经功能恢复的促进作用。

关键词：整合素类神经干细胞脑缺血黏着斑蛋白酪氨酸激酶类