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History and possible mechanisms of prehistoric human migration to the Tibetan Plateau

Science China Earth Sciences 2016年第9期59卷 1765-1778页

作者： ZHANG DongJu DONG GuangHui WANG Hui REN XiaoYan HA PiPu'u QIANG MingRui chen fahui Key Laboratory of Western China's Environmental Systems Ministry of Education College of Earth Environmental Sciences Lanzhou University Lanzhou 730000 China Gansu Provincial Institute of Cultural Relics and Archaeological Research Lanzhou 730000 China Qinghai Provincial Institute of Cultural Relics and Archaeological Research Xining 810007 China Cultural Relic Conservation Institute Lhasa 850000 China

Prehistoric human history on the Tibetan Plateau is a hotly debated topic. Archaeological research on the plateau during the past few decades has enormously improved our understanding of the topic and makes it possible for us to consider the processes and mechanisms of prehistoric human migration to the region. By reviewing the published archaeological research on the Tibetan Plateau, we propose that the first people on the plateau initially spread into the He-Huang region from the Chinese Loess Plateau, and then moved to the low elevation Northeastern Tibetan Plateau and perhaps subsequently to the entire plateau. This process consisted of four stages.(1) During the climatic amelioration of the Last Deglacial period(15–11.6 ka BP), Upper Paleolithic hunter-gatherers with a developed microlithic technology first spread into the Northeastern Tibetan Plateau.(2) In the early-mid Holocene(11.6–6 ka BP), Epipaleolithic microlithic hunter-gatherers were widely distributed on the northeastern plateau and spread southwards to the interior plateau, possibly with millet agriculture developed in the neighboring low elevation regions.(3) In the mid-late Holocene(6–4 ka BP), Neolithic millet farmers spread into low elevation river valleys in the northeastern and southeastern plateau areas.(4) In the late Holocene(4–2.3 ka BP), Bronze Age barley and wheat farmers further settled on the high elevation regions of the Tibetan Plateau, especially after 3.6 ka BP. Finally, we suggest that all of the reported Paleolithic sites earlier than the LGM on the Tibetan Plateau need further examination.

关键词： Tibetan Plateau Prehistoric archaeology Human migration Driving mechanisms

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Structure tailorable triple-phase and pure double-polar-phase flexible IF-WS_(2)@poly(vinylidene fluoride)nanocomposites with enhanced electrical and mechanical properties

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Journal of Materiomics 2020年第3期6卷 563-572页

作者： Dong Guo Kai Cai Pingye Deng Guoning Si Liangying Sun fahui chen Honglong Ning Li Jin Jingtao Ma School of Medical Instrument&Food Engineering University of Shanghai for Science&TechnologyShanghai200093China School of Materials Science&Engineering Beihang UniversityBeijing100191China Beijing Center for Physical and Chemical Analysis Beijing100089China Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou510640China Electronic Materials Research Laboratory School of Electronic and Information EngineeringXi’an Jiaotong UniversityXi’an710049China State Key Laboratory of New Ceramics and Fine Processing Tsinghua UniversityBeijing100084China

A new low-cost high-permittivity flexible nanocomposite consisting of a polyvinylidene fluoride(PVDF)matrix and fullerene-like tungsten disulfide nanoparticle(IF-WS2 NP)filler was fabricated via a simple solution route.A comprehensive investigation by X-ray diffraction,attenuated total reflection-infrared spectroscopy,and differential scanning calorimetry(DSC)showed that 0.5e1 vol% of IF-WS_(2) induced a nonpolar α-phase to coexisting triple-phase transition in PVDF,whereas a slightly higher loading of 2 vol% induced pure double-polar β- and γ-*** results indicate that the structure and properties of the fabricated nanocomposite are easily *** during heating and cooling cycles and morphology observations further indicated that a polar phase was induced by the nucleation effect of the IF-WS2 NPs and electrostatic *** a consequence of the multiphase coexistence and structure homogeneity,nanocomposites with approximately 0.5-1 vol% of IF-WS_(2) NPs showed enhanced dielectric and energy-storage performance as well as enhanced tensile strength and *** new phase-tailorable nanocomposites with balanced properties are promising for applications as energystorage capacitors,piezoelectric sensors,and other flexible multifunctional *** results of this study will serve to deepen the understanding of the polymer polymorph and provide directions on new routes for fabrication of smart materials.

关键词： PVDF Polymorph Permittivity Piezoelectricity Flexibility

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玉米产量构成因素分析

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贵州农业科学 2007年第2期35卷 47-48页

作者：陈发辉郑常祥贵阳市乌当区种子管理站贵州贵阳550013 贵州省旱粮研究所贵州贵阳550006

为了弄清影响玉米产量性状的主要因素,为玉米生产和育种提供参考,进行了玉米产量构成因素研究。结果表明,玉米穗重、行粒数、吐丝期对穗粒重的影响较大,株高、籽粒含水量对穗粒重的影响较小,行粒数、株高、籽粒含水量、吐丝期均通过穗... 详细信息

为了弄清影响玉米产量性状的主要因素,为玉米生产和育种提供参考,进行了玉米产量构成因素研究。结果表明,玉米穗重、行粒数、吐丝期对穗粒重的影响较大,株高、籽粒含水量对穗粒重的影响较小,行粒数、株高、籽粒含水量、吐丝期均通过穗重间接地对穗粒重产生较大的影响。

关键词：玉米产量构成因素

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基于有限元模型的人行悬索桥舒适度检测研究

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江西建材 2024年第5期 95-97,100页

作者：向艳国陈法辉刘如意深圳高速工程检测有限公司广东深圳518000

文中阐述了人行悬索桥舒适度评估的重要性和必要性,以某人行天桥工程为例,建立了人行悬索桥的有限元空间模型,在行人荷载激励作用下进行自振特性和加速度分析,旨在对基于有限元模型的人行悬索桥舒适度进行研究,为同类型人行悬索桥舒适... 详细信息

文中阐述了人行悬索桥舒适度评估的重要性和必要性,以某人行天桥工程为例,建立了人行悬索桥的有限元空间模型,在行人荷载激励作用下进行自振特性和加速度分析,旨在对基于有限元模型的人行悬索桥舒适度进行研究,为同类型人行悬索桥舒适度评价提供参考。

关键词：结构模型悬索桥人行天桥舒适度有限元

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丹酚酸B通过调控AMPK介导的铁死亡保护缺氧/复氧诱导的肾小管上皮细胞的损伤

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海南医学院学报 2024年第15期30卷 1147-1155页

作者：赵静宇陈发慧郝亚杰韩秀涛任茜雅田瑞雪周晓霜山西中医药大学第三临床学院山西晋中030619 山西医科大学第五临床医学院肾内科山西太原030012 山西省人民医院肾内科山西太原030012

目的:探究丹酚酸B(Salvianolic acid B,Sal B)对于缺氧/复氧(hypoxia/reoxygenation,H/R)所致肾小管上皮细胞损伤的保护作用及其机制。方法:体外实验细胞分组为正常对照(Con)组,Sal B+Con组、H/R组、Sal B+H/R组,以及Con组、H/R组、Sal B+H/R组、H/R+CC(Compound c,AMPK抑制剂)组、H/R+Sal B+CC组两部分。体外实验用CCK‑8法检测HK‑2细胞活性;细胞震碎,取上清,用酶标仪检测GSH和MDA的含量;Western blot检测p‑AMPK、GPX4、ACSL4和FSP1蛋白的表达情况;细胞免疫荧光检测铁死亡指标GPX4、ACSL4蛋白的表达情况;流式细胞术检测线粒体膜电位和细胞凋亡。结果:体外实验结果显示,Sal B在20~160μmol/L对正常HK‑2细胞活性无明显毒性(P>0.05);与模型组相比,20、40、80μmol/L的Sal B呈剂量依赖性提高HK‑2细胞的活性(P<0.01)。与模型组相比,H/R+Sal B组细胞MDA含量降低,GSH含量升高,p‑AMPK、GPX4和FSP1蛋白的表达水平升高,ACSL4蛋白的表达降低,细胞线粒体膜电位显著升高,细胞凋亡率显著下降(P<0.05);H/R+AMPK组较H/R+Sal B组FSP1和GPX4蛋白表达水平降低,ACSL4蛋白的表达水平升高(P<0.05),细胞线粒体膜电位显著降低(P<0.05),加入Sal B可以逆转这一情况(P<0.05)。结论:Sal B可减轻H/R的肾小管上皮细胞的损伤,其机制可能与激活AMPK通路减轻肾小管上皮细胞铁死亡有关。

关键词：急性肾损伤丹酚酸B 铁死亡 AMPK 缺氧/复氧

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扶镜手在腹腔镜胰十二指肠切除术中的作用及配合流程

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中华肝胆外科杂志 2019年第8期25卷 606-610页

作者：吴浩然程发辉段小辉魏荣光周舟田朕安张恒张鸿渐毛先海湖南省人民医院肝胆外科长沙410005

目的探讨扶镜手在腹腔镜胰十二指肠切除术(LPD)中的作用及配合流程。方法回顾性分析2014年1月至2017年3月在湖南省人民医院肝胆外科行LPD的101例患者的围术期资料,总结扶镜手在术中的作用及关键术野显露的配合流程。结果101例均在3D腹... 详细信息

目的探讨扶镜手在腹腔镜胰十二指肠切除术(LPD)中的作用及配合流程。方法回顾性分析2014年1月至2017年3月在湖南省人民医院肝胆外科行LPD的101例患者的围术期资料,总结扶镜手在术中的作用及关键术野显露的配合流程。结果101例均在3D腹腔镜下完成胰十二指肠切除术,无中转开腹手术,手术时间(326.0±55.6)min,切除时间(174.4±42.5)min;消化道重建时间(101.0±21.4)min;胰肠吻合时间(40.5±8.7)min;胃肠吻合时间(26.3±5.5)min;胆肠吻合时间(24.4±6.5)min;术中出血(175.6±41.1)ml。术后病理为胆总管下端癌27例(26.7%)、壶腹部癌23例(22.8%)、十二指肠乳头癌39例(38.6%)、胰腺导管腺癌12例(11.9%),肿瘤直径(2.3±1.3)cm,淋巴结清扫数目为(16.7±4.2)枚,阳性淋巴结为(1.3±1.1)枚。术后平均住院时间14.8(8~29)d;术后发生胰瘘23例,其中生化瘘17例(16.8%)、B级瘘5例(5.0%)、C级瘘1例(1.0%),胆汁漏2例(3.0%),术后出血7例(6.9%);胃排空延迟4例(4.0%);腹腔感染6例(5.9%);肺部感染3例(3.0%);肠梗阻2例(2.0%);3例(3.0%)患者行二次手术,住院30天死亡患者1例(1.0%)。结论扶镜手应把握LPD中的"一轴二面四区",在行大Kocher切口,处理钩突危险三角等关键部位时,清晰显露各重要血管及脏器,及时预警术者,保障手术安全性及流畅性。在吻合时,不断调整视野远近,清晰显露吻合区术野,帮助术者提高缝合精度及吻合质量。

关键词：胰十二指肠切除术腹腔镜扶镜手配合流程

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Geochronology and Geochemistry of the Subduction-related Rocks with High Sr/Y Ratios in the Zedong Area: Implications for the Magmatism in Southern Lhasa Terrane during Late Cretaceous

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Acta Geologica Sinica(English Edition) 2015年第2期89卷 351-368页

作者： chen Yanhong YANG Jingsui XIONG fahui ZHANG Lan LAI Shengmin chen Mei CARMA State Key Laboratory for Continental Tectonics and DynamicsInstitute of GeologyChinese Academy of Geological Sciences School of Earth Sciences and Mineral Resources China University of Geosciences

The southern Lhasa Terrane is famous for its huge magmatic belt which records the magmatism during Mesozoic and Cenozoic. Although the Mesozoic continental-margin setting in the southern Lhasa Terrane has been identified, details of this tectonic setting and the evolution history during the Late Cretaceous remain unclear. To further constrain these issues, we present zircon LA-ICP-MS U-Pb, Hf isotopic and geochemical data of the Gongbari dacites （of the Sangri Group） which intruded by Paleocene granodiorites from the eastern part of the southern Lhasa Terrane, Tibet. New age data indicate that the dacites were generated at -95.4 Ma, which suggests the Sangri Group volcanism may last to Late Cretaceous. The Gongbari dacites are characterized by high Sr （428-758 ppm） contents, low concentration of heavy rare earth elements and Y （e.g. Yb=0.78-1.14 ppm; Y=8.85-11.4 ppm） with high Sr/Y （41.91-67.59） and La/Yb （22.64-30.64） ratios, similar to those of adakite. The rocks are calc-alkaline, metaluminous, enriched in LILEs, depleted in HFSEs, and have positive tar（t） values （＋7.7 to ＋11.6）. The Gongbari dacites were probably produced by partial melting of young and hot subducted Neo- Tethyan oceanic crust under amphibolite to garnet amphibolite-facies conditions. Though the Gangdese Mountains may have formed before Indo-Asian collision, the southern margin of Lhasa Terrane might not go through obviously crustal thickening during the northward subduction of Neo-Tethyan oceanic lithosphere.

关键词： Adakitic dacite Sangri Group Neo-Tethyan Ocean Southern Lhasa Terrane Tibet

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Petrological and Os Isotopic Characteristics of Zedong Peridotites in the Eastern Yarlung–Zangbo Suture in Tibet

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 442-461页

作者： LAI Shengmin YANG Jingsui Yildirim DILEK XIONG fahui JIANG Rui chen Yanhong School of Earth Science and Mineral Resources China University of Geosciences Beijing 100083 China CARMA Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Department of Geology Shideler Hall Miami University Oxford OH 45056 USA Petro China Southwest Oil & Gasfield Company Engineering Technology Research Department Chengdu 618300 China

The Zedong ophiolites in the eastern Yarlung-Zangbo suture zone of Tibet represent a mantle slice of more than 45 km2. This massif consists mainly of mantle peridotites, with lesser gabbros, diabases and volcanic rocks. The mantle peridotites are mostly harzburgite, lherzolite; a few dike-like bodies of dunite are also present. Mineral structures show that the peridotites experienced plastic deformation and partial melting. Olivine （Fos9.7-91.2）, orthopyroxene （Enss-92）, clinopyroxene （En4-49Wo47-slFS2-4） and spinel [Mg^#=lOOxMg/（Mg＋Fe）]=49.1-70.7; Cr^#=（100xCr/（Cr＋Al）=18.8-76.5] are the major minerals. The degree of partial melting of mantle peridotites is 10%-40%, indicating that the Zedong mantle peridotites may experience a multi-stage process. The peridotites are characterized by depleted major element compositions and low REE content （0.08-0.62 ppm）. Their ＂spoon-shaped＂ primitivemantle normalized REE patterns with （La/Sm）N being 0.50-6.00 indicate that the Zedong ultramafic rocks belong to depleted residual mantle rocks. The PGE content of Zedong peridotites （18.19-50.74 ppb） is similar with primary mantle with Pd/Ir being 0.54-0.60 and Pt/Pd being 1.09-1.66. The Zedong peridotites have variable, unradiogenic Os isotopic compositions with 187Os/18Os=0.1228 to 0.1282. A corollary to this interpretation is that the convecting upper mantle is heterogeneous in Os isotopes. All data of the Zedong peridotites suggest that they formed originally at a mid-ocean ridge （MOR） and were later modified in supra-subduction zone （SSZ） environment.

关键词： Os isotopes Zedong peridotites Yarlung-Zangbo suture zone mid-ocean ridge (MOR),supra-subduction zone (SSZ)

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Origin of Listwanite in the Luobusa Ophiolite,Tibet,Implications for Chromite Stability in Hydrothermal Systems

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Acta Geologica Sinica(English Edition) 2015年第2期89卷 402-417页

作者： ZHANG Lan YANG Jingsui Paul T.ROBINSON XIONG fahui chen Yanhong LAI Shengmin chen Mei School of the Earth Sciences and Resources China University of Geosciences CARMA State Key Laboratory for Continental Tectonics and DynamicsInstitute of GeologyChinese Academy of Geological Sciences

Listwanite from the Luobusa ophiolite, Tibet, forms a narrow, discontinuous band along the eastern part of the southern boundary fault. We undertook a detailed petrographic and geochemical study to understand the mineral transformation processes and the behaviour of major and trace elements during listwanite formation. Three alteration zones characterized by distinct mineral components and texture are recognized and, in order of increasing degree of alteration, these are： zonem is rich in serpentine minerals; zonen is rich in talc and carbonates; and zone_Ⅰ is mainly composed of carbonates and quartz. Geochemical data for the three alteration zones show significant modification of some major and trace elements in the protolith, although some oxides show linear correlations with MgO. Gold mineralization is recognized in the Luobusa listwanite and may signify an important target for future mineral exploration. Gold enrichment occurs in both zone_Ⅰ and zone_Ⅱ and is up to 0.91 g/t in one sample from zonei. We show that CO_2-rich hydrothermal fluids can modify both the occurrence and composition of chromite grains, indicating some degree of chromite mobility. Low-Cr anhedral grains are more easily altered than high-Cr varieties. The compositions of chromite and olivine grains in the listwanite suggest a dunite protolith.

关键词： Listwanite mineralogy geochemistry gold mineralization chromite stability

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Pore shrinkage capacity of Shajiang black soils(Vertisols)on the North China Plain and its influencing factors

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Pedosphere 2024年第3期34卷 620-630页

作者： Yueming chen Zhongbin ZHANG Lei GAO Zichun GUO Peng XIONG fahui JIANG Xinhua PENG State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) University of Chinese Academy of Sciences Beijing 100049(China) Jiangxi Agricultural University Nanchang 330045(China)

Different pore sizes present different pore shrinkage capacities in a nonrigid ***,the shrinkage capacities of different pore sizes and their influencing factors are not *** aimed to quantify the shrinkage capacities of different pore sizes(large pores,>50μm;medium pores,0.2-50μm;fine pores,<0.2μm)and determine how soil properties impact soil shrinkage capacity at the regional *** sampling transects from west to east(360 km long,35 samples)and from north to south(190 km long,29 samples)were selected to investigate soil shrinkage capacity and physicochemical properties of at0-20 cm depth in the Vertisol(locally known as Shajiang black soil)region of the North China *** results showed that soil total shrinkage capacity,indicated by the coefficient of linear extensibility(COLE),had a mean value of 0.041-0.051 in the west-east and north-south *** pores had higher pore shrinkage index(PSI)values(0.103-0.109)than medium(0.077-0.096)and fine(0.087-0.091)*** PSI of fine pores showed a fluctuating increasing trend from northwest to southeast,and the fine pore shrinkage capacity determined the COLE(r^(2)=0.789,P<0.001).The PSI of large pores had a significant relationship with soil bulk density(r=0.281,P<0.05)and organic carbon(r=-0.311,P<0.05),whereas those of medium and fine pores were correlated with soil clay content(r=0.381 and 0.687,respectively,P<0.001).In addition,the PSI of fine pores was also correlated with montmorillonite content(r=0.387,P<0.01).It can be concluded that the PSI of large pores is related to anthropogenically influenced soil properties with low stability,whereas those of medium and fine pores are related to pedogenic *** high variability in anthropogenic and pedogenic factors explains the spatial pattern of Vertisol shrinkage capacity on the North China Plain.

关键词： clay content coefficient of linear extensibility pore shrinkage index soil structure spatial distribution swelling

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