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A tropical paleosol at high elevation in the Yulong Mountains and its implication on the uplift of the Tibetan Plateau

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Chinese Science Bulletin 2001年第1期46卷 69-73页

作者： zhengtang Guo Xiaofeng Yao Xitao Zhao Lanying Wei Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

A paleosol dated for about 500-700 kaBP and developed on a glacial deposit at -3 000 in a.s.l. in the Yulong Mountains is studied using soil chemical, morphological and mineralogical methods. The analytical results indicate that this soil was formed under tropical and humid conditions and can be classified as red soil, which cannot be formed in the present alpine environment at the studied site. This implies that the southeast margin of the Tibetan Plateau has experienced intense uplift since the formation of the paleosol. According to the necessary conditions for the formation of the modern red soil in China, we estimate that the

关键词： Yulong Mountains paleosol paleoenvironment uplift of the Tibetan Plateau.

骨形态发生蛋白2.小儿颅骨缺损自行修复中的作用

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国际神经病学神经外科学杂志 2024年第2期51卷 85-90页

作者：李政堂郭雅鑫邵国张春阳内蒙古科技大学包头医学院内蒙古包头014010 内蒙古鄂尔多斯市中心医院康复科内蒙古鄂尔多斯017000 内蒙古科技大学包头医学院第一附属医院神经外科内蒙古包头014010 包头医学院神经外科疾病研究所(转化医学) 内蒙古包头014010 内蒙古自治区骨组织再生与损伤修复工程技术中心内蒙古包头014010 深圳市龙岗区第三人民医院转化医学中心广东深圳518100

颅脑外伤在小儿各类外伤中占据首位。去骨瓣减压术为神经外科常见减少颅内压的手术方式,颅骨缺失会导致患儿脑组织缺少颅骨保护,颅骨作为脑组织最直接的保护屏障,若缺损不及时修补会因体位、情绪和腹压等会导致脑组织在颅内发生移动,从... 详细信息

颅脑外伤在小儿各类外伤中占据首位。去骨瓣减压术为神经外科常见减少颅内压的手术方式,颅骨缺失会导致患儿脑组织缺少颅骨保护,颅骨作为脑组织最直接的保护屏障,若缺损不及时修补会因体位、情绪和腹压等会导致脑组织在颅内发生移动,从而造成脑穿通性畸形、癫痫发作和脑变性萎缩等疾病。小儿有好动、依从性差、自我保护能力差等特点,更容易形成二次伤害。小儿处于生长发育期,缺乏颅骨的保护,颅脑容易受到二次伤害,还会影响患儿神经系统的正常发育,造成患儿智力低下,神经系统发育不完善等相关并发症,所以重建颅骨的完整对患儿的生长发育至关重要。未成熟硬脑膜对颅骨的发育和缺损修复有重要作用,2.以下的儿童能够修复巨大的颅骨缺损,而成年人则缺乏这种内源性能力。幼龄动物骨缺损中骨形态发生蛋白2.BMP2.上调,表明BMP2.骨组织再生中具有重要作用。许多生物调节因子可调控BMP2.活性。该综述就BMP2.小儿颅骨缺损修复中的研究现状做总结。

关键词：颅骨缺损修复骨形态发生蛋白2 硬脑膜

Distribution of n-alkanes in Miocene loess in Qinan, western Chinese Loess Plateau, and its palaeoenvironmental implications

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Science China Earth Sciences 2017年第5期60卷 921-928页

作者： SHEN JiaHeng XIAO GuoQiao WANG ZhiXiang SUN Qing WU HaiBin ZHANG ChunXia GUO zhengtang Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Biogeology and Environmental Geology School of Earth Sciences China University of Geosciences Wuhan 430074 China National Research Center of Geoanalysis Beijing 100037 China Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101 China

Neogene eolian successions are one of the most important terrestrial palaeoenvironmental archives in East ***, they have received far less attention than Quaternary loess deposits, especially in the case of lipid biomarker *** order to obtain a better insight into the early-middle Miocene palaeoenvironment, we conducted a study of n-alkane biomarkers from sediments of the QA-I section(Qinan) in the western Chinese Loess Plateau, and compared the results with those of previous n-alkane analyses of eolian and aquatic sediments of varying age. Our principal results are as follows:(1) All QA-I samples contain n-alkanes ranging from C_(14) to C_(35), among which the relative content of short-chain n-alkanes(C_(14)–C_(2.)) from microorganisms is significantly greater than that of long-chain n-alkanes(C_(2.)–C_(35)) from the waxes of terrestrial higher plants;the main peak is at C_(16)–C_(18). All samples have a relatively lower abundance of medium-chain n-alkanes(C_(2.)–C_(2.)) than that of long-and short-chain n-alkanes, similar to strongly weathered palaeosols in Quaternary loess and Late Miocene-Pliocene Hipparion Red-Earth; however, this distribution is significantly different from that in weakly-weathered loess of Quaternary loess and Late Miocene-Pliocene Hipparion Red-Earth, as well as from aquatic sediments.(2. Despite some odd-over-even carbon predominance of long-chain n-alkanes in the QA-I samples, the carbon preference index(CPI) values are significantly lower than those of most of the weakly-weathered sediments. Our results show that strong weathering and microbial processes have significantly altered the n-alkanes in the Miocene eolian deposits in Qinan, and led to a significant oxidation and degradation of long-chain n-alkanes and the predominance of short-chain n-alkanes from bacteria. Therefore, the contribution of microorganism to total organic carbon(TOC) and its resulting in carbon isotopic composition should be carefully assessed in f

关键词： Miocene Loess n-alkane Palaeoenvironment Qinan

运动改善ASMT基因敲除小鼠抑郁行为的海马蛋白质组学机制

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上海体育大学学报 2024年第3期48卷 36-48页

作者：章森刘文彬夏杰李玲侠黄卓淳邹勇漆正堂刘微娜华东师范大学青少年健康评价与运动干预教育部重点实验室上海200241 华东师范大学体育与健康学院上海200241

目的利用定量蛋白质组学技术探究N-乙酰基-5-羟色胺-甲基转移酶(N-acetyl-5-hydroxytryptamine-methyltransferase,ASMT)基因敲除及运动干预对小鼠抑郁行为及海马蛋白质组的影响。方法将雄性ASMT基因敲除小鼠及野生型小鼠随机分为安静... 详细信息

目的利用定量蛋白质组学技术探究N-乙酰基-5-羟色胺-甲基转移酶(N-acetyl-5-hydroxytryptamine-methyltransferase,ASMT)基因敲除及运动干预对小鼠抑郁行为及海马蛋白质组的影响。方法将雄性ASMT基因敲除小鼠及野生型小鼠随机分为安静组和运动组。5周的游泳运动干预结束后全部进行抑郁行为学检测。行为学结束后进行麻醉处死取海马组织。采用TMT标记定量蛋白质组学技术检测海马组织中的蛋白表达情况,并运用生物信息学方法分析。结果ASMT基因敲除后小鼠具有显著的抑郁行为表型,游泳运动干预后可以显著改善。筛选出的差异蛋白功能集中在突触信号通路、突触化学传递的调控、突触囊泡循环、神经发生、神经系统发育的调控、长时程突触增强、SNARE复合体聚集等。结论ASMT基因敲除可能会通过海马突触前膜的SNARE家族蛋白过度表达诱导谷氨酸的过度释放并产生神经毒性,进而产生抑郁行为;游泳运动可能通过调节突触转运相关蛋白SNAP2.维持神经递质稳态,促进神经发生水平和突触可塑性,进而使ASMT基因敲除小鼠抑郁行为得到改善。

关键词： N-乙酰基-5-羟色胺-甲基转移酶游泳运动抑郁行为海马蛋白质组学

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Extension of drylands in northern China around 2.0 kaBP linked with the uplift of the southeast margin of Tibetan Plateau

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Chinese Science Bulletin 2002年第20期47卷 1739-1745页

作者： WU Haibin GUO zhengtang FANG Xiaomin ZHANG Jiawu CHEN Fahu Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Department of Geography Lanzhou UniversityLanzhou 730000China Institute of Earth Environment Chinese Academy of SciencesXi'an 710075China

Study on two loess sections, one located at Wu-wei near the Tengger Desert in northwestern China, another located near Ganzi at the southeast margin of the Tibetan Plateau in southwest China, reveals a coeval drying step occurred at -2.0 kaBP. It is expressed by the increase in eolian grain-size at Wuwei, and by a drastic extension of C4 plants and a decrease of loess chemical weathering intensity at Ganzi. Examination of the available eolian data indicates that the event has also been clearly documented in the loess sections near the deserts in northern China, and in the eolian records from the North Pacific. On the contrary, the signal is rather weak for the central and southern Loess Plateau regions as well as for Central Asia, where the climates are influenced by the southeast Asian monsoon and the westerlies, respectively. Since the climate at Ganzi is under strong control of the southwest Asian monsoon, we interpret this drying step as a result of decreased influence of the southwest summer

关键词： aridification loess-paleosol sequences organic carbon isotope chemical weathering intensity Tibetan Plateau.

Concentration of linoleic acid from cottonseed oil by starch complexation

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Chinese Journal of Chemical Engineering 2019年第4期27卷 845-849页

作者： Dan Liang Yufeng Hu Weiting Ma zhengtang Zhao Siqi Jiang Yichuan Wang Xianming Zhang State Key Laboratory of Heavy Oil Processing China University of Petroleum

The extraction of linoleic acid from fatty acids(FA) of the cottonseed oil using starch–FA complexes was developed for the first time. We showed that starch can form inclusion complexes of different strengths with FA and that the different strengths stem from the differences in chain length, degree of unsaturation, and position of double bonds of FA. The optimal separation conditions were determined as follows: The inclusion temperature is 69 °C, the inclusion time is 30 min, the starch/FA mass ratio is 10:1, and the ratio of the volume of methanol–water solution and the mass of FA is 18:1. Compared to urea inclusion complexation, starch complexation has milder reaction temperature and shorter reaction time. Under these conditions, linoleic acid can be concentrated from 38.9% to 70.04% by one-off extraction. Moreover, the experimental results demonstrate the almost perfect reusability of starch. These results show that starch complexation is a promising method that can be used to obtain highly concentrated linoleic acid from cottonseed oil.

关键词： Starch Linoleic acid Starch complexation Starch–FA complex Cottonseed oil

Thick Miocene eolian deposits on the Huajialing Mountains:The geomorphic evolution of the western Loess Plateau

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Science China Earth Sciences 2011年第2期54卷 241-248页

作者： ZHAN Tao GUO zhengtang WU HaiBin GE JunYi ZHOU Xin WU ChunLin ZENG FangMing Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The geomorphic evolution of northwestern China during the Cenozoic has been a subject of much geological interest because of its link with the uplift of the Himalayan-Tibetan *** information about these changes is recoverable from the sedimentary sequences of the *** report here on the thick eolian deposits mantling the Huajialing Mountains,a relatively flat mountain range in the western Loess *** of magnetic susceptibility stratigraphy with the QA-I Miocene eolian sequence dates a 134.7 m section(NL-VII) for the interval from 18.7 to 11.8 Ma,as confirmed by micro-mammalian *** eolian deposits demonstrate a much wider distribution of the Miocene eolian deposits,and also indicate that the topography contrasts in the western Loess Plateau,including the uplifts of the Huajialing Mountains and the bedrock highlands in the Qinan region,were formed by the early *** near-continuous Miocene eolian sequence from 18.7 to 11.8 Ma indicates that the substratum of Huajialing had not experienced any intense tectonic changes during this time interval,which suggests further,the relative tectonic stability of the nearby Tibetan Plateau.

关键词： Miocene eolian deposits Huajialing Tibetan Plateau Cenozoic geomorphic evolution

Properties of Gallium Phosphide Thick Films Prepared on Zinc Sulfide Substrates by Radio-Frequency Magnetron Sputtering

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Journal of Materials Science & Technology 2010年第1期26卷 93-96页

作者： Yangping Li and zhengtang Liu School of Materials Science and Engineering, Northwestern Polytechnical University, Xi an 710072. China [a] School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 China

Radio-frequency （RF） magnetron sputtering was employed to prepare gallium phosphide （GAP） thick films on zinc sulfide （ZnS） substrates by sputtering a single crystalline GaP target in an Ar atmosphere. The infrared （IR） transmission properties, structure, morphology, composition and hardness of the film were studied. Results show that both amorphous and zinc-blende crystalline phases existed in the GaP film in almost stoichiometric amounts. The GaP film exhibited good IR transmission properties, though the relatively rough surface and loose microstructure caused a small loss of IR transmission due to scattering. The GaP film also showed a much higher haraness than the ZnS substrate, thereby providing good protection to ZnS.

关键词： Radio-frequency magnetron sputtering Gallium phosphide Thick film Infrared transmission

Where were the monsoon regions and arid zones in Asia prior to the Tibetan Plateau uplift?

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National Science Review 2015年第4期2卷 403-416页

作者： Xiaodong Liu Qingchun Guo zhengtang Guo Zhi-Yong Yin Buwen Dong Robin Smith State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences CAS Center for Excellence in Tibetan Plateau Earth Sciences University of the Chinese Academy of Sciences Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Department of Environmental & Ocean Sciences University of San Diego National Centre for Atmospheric Science University of Reading

The impact of the Tibetan Plateau uplit on the Asian monsoons and inland arid climates is an important but also controversial question in studies of paleoenvironmental change during the Cenozoic. In order to achieve a good understanding of the background for the formation of the Asian monsoons and arid environments, it is necessary to know the characteristics of the distribution of monsoon regions and arid zones in Asia before the plateau uplit. In this study, we discuss in detail the paterns of distribution of the Asian monsoon and arid regions before the plateau uplit on the basis of modeling results without topography from a global coupled atmosphere–ocean general circulation model, compare our results with previous simulation studies and available biogeological data, and review the uncertainties in the current knowledge. Based on what we know at the moment, tropical monsoon climates existed south of 2.?N in South and Southeast Asia before the plateau uplit, while the East Asian monsoon was entirely absent in the extratropics. hese tropical monsoons mainly resulted from the seasonal shits of the Inter-Tropical Convergence Zone. here may have been a quasi-monsoon region in central-southern Siberia. Most of the arid regions in the Asian continent were limited to the latitudes of 2.–40?N, corresponding to the range of the subtropical high pressure year-around. In the meantime, the present-day arid regions located in the relatively high latitudes in Central Asia were most likely absent before the plateau uplit. he main results from the above modeling analyses are qualitatively consistent with the available biogeological data. hese results highlight the importance of the uplit of the Tibetan Plateau in the Cenozoic evolution of the Asian climate patern of dry–wet conditions. Future studies should be focused on efects of the changes in land–sea distribution and atmospheric CO2.concentrations before and ater the plateau uplit, and also on cross-comparisons between numer

关键词： the Tibetan Plateau uplit the Asian monsoons