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1Inhibiting effect of antisense oligonucleotides phosphorthioate on gene expression of TIMP-1 in rat liver fibrosis显示文摘AIM To observe the inhibition of antisenseoligonucleotides (asON) phosphorthioate to thetissue inhibitors metalloproteinase-1 (TIMP-1)gene and protein expression in the liver tissue ofimmunologically induced hepatic fibrosis rats.The possibility of reversing hepatic fibrosisthrough gene therapy was observed.METHODS Human serum albumin (HSA) wasused to attack rats, as hepatic fibrosis model, inwhich asONs were used to block the gene andprotein expressing TIMP-1. According to theanalysis of modulator, structure protein, codingseries of TIMP-1 genome, we designed fourdifferent asONs. These asONs were injected intothe hepatic fibrosis models through coccygealvein. The results was observed by RT-PCR formeasuring TIMP-1 mRNA expression,immunohistochemistry and in situ hybridizationfor collagen Ⅰ, Ⅲ, special staining of collagenfiber, and electron microscopic examination.RESULTS Hepatic fibrosis could last within 363days in our modified model. The expressinglevel of TIMP-1 was high during hepatic fibrosisprocess. It has been proved by theimmunohistochemical and the electronmicroscopic examination that the asONphosphorthioate of TIMP-1 could exactly expressin vivo. The effect of colchicine wasdemonstrated to inhibit the expressing level ofmRNA and the content of collagen Ⅰ, Ⅲ in theliver of experimental hepatic fibrosis rats.However, the electron microscopy research andthe pathologic grading of hepatic fibrosisshowed that there was no significant differencebetween the treatment group and the modelgroup (P>0.05).CONCLUSION The experimental rat model ofhepatic fibrosis is one of the preferable modelsto estimate the curative effect of anti-hepaticfibrosis drugs. The asON phosphorthioate ofTIMP-1 could block the gene and proteinexpression of TIMP-1 in the liver of experimentalhepatic fibrosis rats at the mRNA level. It ispossible to reverse hepatic fibrosis, and it isexpected to study a new drug of anti-hepaticfibrosis on the genetic level. Colchicine has verylimited therapeutic effect on hepatic fibrosis,furthermore, its toxicity and side effects areobvious.Qing He Nie Yong Qian Cheng Yu Mei Xie Yong Xing Zhou Yi Zhan Cao The Center of Infectious Disease Diagnosis and Treatment of PLA,Tangdu Hospital,Forth Military Medical University,Xi’an 710038,Shaanxi Province,ChinaDr,Qing He Nie graduated from Qinghai Medical College as a doctor in 1983,got master degree at Beijing 302 Army Hospital in 1993,got doctor degree at the Third Military Medical University in 1998,engaged in postdoctoral research at the Fourth Military Medical University from 1998 to 2000,now an associate professor,specialized in clinical and experimental research of infectious diseases,had more than 90 papers published,coauthor of ten books,first author of one book. 2001World Journal of Gastroenterology2001,7,3:73
2Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago显示文摘A typical sequence of fluvial terraces and aeolian deposits overlying these terraces were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14 million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identified. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (1030 samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 samples). The luminescence dating and stratigraphic correlation suggest that terraces of T11, T10,T8, T7, T3, T2, T1 were formed at 14, 11.3, 1.55, 1.2, 0.15, 0.07 and 0.01 million years ago, respectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace sequence provides an ideal geological record of the uplift process of the northeastern Qinghai-Tibet during the past 14 million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14, 11.3, 1.2 and 0.15 million years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12 million years in the Miocene era (between the T11 and T9), while the Huangshui River had incised 432 m during the past 1.2 million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the northeastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts. There was a significant readjustment of the fluvial catchment during 1.55-1.2 million years ago: before this time, the paleoriver flowed to southwest. After this time the Huangshui River flows to southeast. A tectonic movement dominates reorganization of this fluvial system.LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3, MA Haizhou2, LI Zhen4, TAN Hongbing2 & WANG Xianyan1 1. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075 China 2. Qinghai Institute of Salt Lakes, Chinese Academy of Sciences. Xining 810008, China 3. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 4. Department of Geography, Qinghai Normal University, Xining 810008, China 2004Science China Earth Sciences2004,47,9:51
3Quantitative relationship between pollen and vegetation in northern China显示文摘205 surface pollen samples from different communities in Northern China were analyzed to understand the quantitative relationship between pollen and its original vegetation. Pollen analysis and vegetation investigation show that the pollen assemblages differ a lot in different vegetation regions. Arboreal pollen account for more than 30% in temperate broad-deciduous forests region. In temperate steppe regions, herb pollen percentages are more than 90%, where Artemisia and Chenopodiaceae are domi- nant pollen types with Artemisia percentages more than 30%. In temperate desert, Chenopodiaceae pollen percentages are more than Artemisia, where ferns are rare. Cyperaceae pollen percentages are more than 20% in sub-alpine or cold meadows. The relations between pollen percentages and vegeta- tion cover indicate that most arboreal pollen shows a close relationship with parent plant covers, most shrubby pollen types have more or less correlations, but most herbs do not show clear correlations. For arboreal pollen types, Picea pollen shows the closest correlation with spruce trees coverage, then is Quercus and Carpinus. Betula, Larix and Juglans have also high correlation coefficients with their plants coverage, but Betula pollen is of overrepresented pollen type and more than 40% in birch forest, while Larix and Juglans pollen is underrepresented and pollen percentages are more than 10% in Larix or Juglans pure forests. Pinus is of overrepresented pollen type, and pollen percentages have some relations with plants cover. Pine forest might present when Pinus pollen percentages are more than 30%. The relations between Ulmus and Populus pollen percentages and vegetation cover are not close, where they are mixed with other arbors, they cannot be recorded easily, but if their pollen percentages are more than 1%, Ulmus or Populus trees should exist. For shrubby pollen types, the correlation be- tween Vitex pollen percentages and vegetation cover is the highest, then is Corylus, Tamariaceae and Nitraria, and their pollen percentages are less than 1% where original plant are absent. Caragana and Spiraea pollen percentages have some relations with vegetation cover. The relations between pollen percentages and vegetation cover are not clear for Rosaceae and Saxifragaceae. For herb pollen types, Cyperaceae pollen has the closest correlation with vegetation cover, where pollen percentages are more than 20% when Cyperaceae are constructive or dominant species in vegetation, and pollen per- centages are less than 5% where Cyperaceae are not constructive or dominant species (cover less than 30%). Artemisia and Chenopodiaceae pollen percentages mainly have close relations with ecological regions. The relations between pollen percentages and cover are not clear for Gramineae, Legumi- nosae and Compositae.XU QingHai LI YueCong YANG XiaoLan ZHENG ZhenHua 2007Science China Earth Sciences2007,50,4:41
4Discovery of eclogite inclusions and its geological significance in early Jurassic intrusive complex in Xuzhou-northern Anhui, eastern China显示文摘The early Jurassic intrusive complex is chiefly made of monzodioritic porphyry in northern Anhui and northern Jiangsu, which emplaced in 191 Ma. The intrusive complexes contain a lot of eclogite inclusions which belong to eclogite and garnet-pyroxenite. The inclusions had undergone eclogite facies high-pressure metamorphism and am-phibolite facies retrogressive metamorphism. The garnets in eclogite inclusions are mainly almandine varieties and clino-pyroxenes are omphacite and augite. The mineral assemblage and P-T estimation results show that P-T conditions of eclogite facies metamorphism and amphibolite facies retrogressive metamorphism are over 1.2-1.5 GPa, 709-861°C and 0.7-1.03 GPa, 666-738°C, respectively. The discovery of the high-pressure xenoliths not only is of important significance to understand the composition and structure of deep crust in southern edge of North China Platform, but also can be of important influence on realizing the subduc-tion-collision-exhumation evolutional processWenliang Xu Dongyan Wang Xiaochun Liu Qinghai Wang Jingqian Lin 2002Chinese Science Bulletin2002,47,14:37
5SHRIMP zircon U-Pb dating in Jingshan 'migmatitic granite', Bengbu and its geological significance显示文摘The petrographic characteristics of Jingshan 'migmatitic granite' and the occurrence of the magmatic zircons indicate that the granite was formed by normal crystallization of felsic melts. All zircons in the granite have inherited cores and fine-scale oscillatory zoning rims of magmatic origin. It is realized that the granite was formed at 160.2±1.3 Ma through dating magmatic zircons. The generation of the granitic magma could be related to the lithospheric mantle and/or lower crust delamination after the ultrahigh pressure metamorphism (UHPM) in Triassic. Most inherited zircons yield the ages of 217.1±6.6 Ma, which is consistent with the peak UHPM in the Dabie-Sulu orogenic belt. Some of the inherited zircons (433-722 Ma) constitute a discordia line with the upper intercept age of 850+85/-68 Ma and a lower intercept age of 261+100/-140 Ma. These ages imply that the granite could be derived from the partial melting of the crustal materials of the South China Block that was intensively superimposed by the UHPM. The UHPM could be the reason for the major Pb loss at ±220 Ma.XU Wenliang, WANG Qinghai, YANG Debin, LIU Xiaochun & GUO Jinghui College of Earth Sciences, Jilin University, Changchun 130061, China Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China Institute of Geology & Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2005Science China Earth Sciences2005,48,2:32
6Humid Medieval Warm Period recorded by magnetic characteristics of sediments from Gonghai Lake, Shanxi, North China显示文摘Variations in monsoon strength, moisture or precipitation in eastern China during the MWP reflected by different climatic records have shown apparent discrepancies. Here, detailed environmental magnetic investigations and mineralogical analyses were conducted on lacustrine sediments of Core GH09B1 (2.8 m long) from Gonghai Lake, Shanxi, North China, concerning the monsoon history during the MWP. The results demonstrate that the main magnetic mineral is magnetite. The sediments with relatively high magnetic mineral concentrations were characterized by relatively fine magnetic grain sizes, which were formed in a period of relatively strong pedogenesis and high precipitation. In contrast, the sediments with low magnetic mineral concentrations reflected an opposite process. The variations of magnetic parameters in Gonghai Lake sediments were mainly controlled by the degree of pedogenesis in the lake drainage basin, which further indicated the strength of the Asian summer monsoon. The variations in the and S 300 parameters of the core clearly reveal the Asian summer monsoon history over the last 1200 years in the study area, suggesting generally abundant precipitation and a strong summer monsoon during the Medieval Warm Period (MWP, AD 910–1220), which is supported by pollen evidence. Furthermore, this 3–6-year resolution environmental magnetic record indicates a dry event around AD 980–1050, interrupting the generally humid MWP. The summer monsoon evolution over the last millennium recorded by magnetic parameters in sediments from Gonghai Lake correlates well with historical documentation (North China) and speleothem oxygen isotopes (Wanxiang Cave), as well as precipitation modeling results (extratropical East Asia), which all indicate a generally humid MWP within which centennial-scale moisture variability existed. It is thus demonstrated that environmental magnetic parameters could be used as an effective proxy for monsoon climate variations in high-resolution lacustrine sediments.LIU JianBao CHEN FaHu CHEN JianHui XIA DunSheng XU QingHai WANG ZongLi LI YueCong 2011Chinese Science Bulletin2011,56,23:28
7Climate change tendency and grassland vegetation response during the growth season in Three-River Source Region显示文摘Climate change,climate suitablity change for grassland vegetation,and grassland response to climate change during the growth season are studied systematically by using meteorological data of temperature,precipitation,and length of sunlight from 1961 to 2007,NOAA/AVHRR NDVI from 1982 to 2006,and observations of grass height,biomass,and coverage in enclosed grassland from 1994 to 2006.Two models are developed to evaluate climate change and the climatic suitability of grassland vegetation growth.Average temperature,accumulative precipitation,and length of sunlight during the growth season increased from 1961 to 2007 at rates of 0.24°C/10 yr,2.32 mm/10 yr,and 2.81 h/10 yr,respectively.The increase rates of ave-rage temperature between April and May,and between June and August are 0.17 and 0.30°C/10 yr;accumulative rainfall between April and May increased at a rate of 2.80 mm/10 yr,and accumulative rainfall between June and August decreased at a rate of 0.38 mm/10 yr;the increase rates of accumulative length of sunlight between April and May,and between June and August are 2.15 and 1.2 h/10 yr.The climatic suitability of grassland vegetation growth showed an increasing trend,and the increase rate between April and May is greater than that between June and August.Both NDVI observations from 1982 to 2006 and measurements of grass height,dry biomass,and coverage from 1994 to 2006 show that the climate change has resulted in an increase in plant productivity of the grassland in Three-River Source Region.If some protection measures are taken as soon as possible,the deteriorated grassland in Three-River Source Region can recover.QIAN Shuan1,FU Yang2 & PAN FeiFei3 1 National Meteorological Center,Beijing 100081,China 2 Qinghai Meteorological Research Institute,Xining 810001,China 3 Department of Geography,University of North Texas,Denton,TX 76203,USA 2010Science China Earth Sciences2010,53,10:25
8Investigation of heavy metal partitioning influenced by flue gas moisture and chlorine content during waste incineration显示文摘The impact of moisture on the partitioning of the heavy metals including Pb,Zn,Cu and Cd in municipal solid waste (MSW) was studied in a laboratory tubular furnace.A thermodynamic investigation using CHEMKIN software was performed to compare the experimental results.Simulated waste,representative of typical MSW with and without chlorine compounds,was burned at the background temperature of 700 and 950°C,respectively.In the absence of chlorine,the moisture content has no evident effect on the volatility of Pb,Zn and Cu at either 700 or 950°C,however,as flue gas moisture increasing the Cd distribution in the bottom ash increased at 700°C and reduced at 950°C,respectively.In the presence of chlorine,the flue gas moisture reduced the volatility of Pb,Zn and Cu due to the transformation of the more volatile metal chlorides into less volatile metal oxides,and the reduction became significant as chlorine content increase.For Cd,the chlorine promotes its volatility through the formation of more volatile CdCl 2.As a result,the increased moisture content increases the Pb,Zn,Cu and Cd concentrations in the bottom ash,which limits the utilization of the bottom ash as a construction material.Therefore,in order to accumulate heavy metals into the fly ash,MSW should be dried before incineration.Qinghai Li,Aihong Meng,Jinyan Jia,Yanguo Zhang Department of Thermal Engineering,Key Laboratory for Thermal Science and Power Engineering of the Ministry of Education of China,Tsinghua University,Beijing 100084,China. 2010Journal of Environmental Sciences2010,22,5:24
9中日竞走运动员高原训练的生理机能及运动能力的研究显示文摘10名世居高原(2260米)的中国竞走运动员和10名居平原(10m)的日本竞走运动员在多巴(2366米),作4周高原训练。高原训练后期与前期、高原与平原相比,观察到有益的代偿性改变。如运动后的恢复心率(1分至1分10秒)下降加快(13次/分降至105次/分);在负荷心率相近条件下,步速加快(3.61m/s增至3.80m/s),无氧阈速度加快(中方,3.01增至3.22;日方,2.78增至3.30m/s);左室功能有改善(SV:日男由85.4→98.1ml;C1:中男由3.10→3.28L/m^2·min);乳酸—速度曲线右移(日男由7.2→5.4mM,中男由6.2→5.6mM);缓冲系统的能力有改善(女子:BE,—4.7→0.2mM;HCO_3,18.6→25.2mM);肺通气功能有所加强(MVV:中方,108.6→113.5L/min,日方,139.8→146.6L/min)。高原训练后,下平原比赛,中日各有8名队员提高了本人最好成绩。Li Hua, et al. (Qinghai Institute of Sports Science, Xining, China 810000)J. Aoki, et al(University of Zuntendo, Japan) Sino-Japanese Research Group for Altitude Training 1995体育科学1995,15,5:23
10Neoproterozoic basic magmatism in the southeast margin of North China Craton:Evidence from whole-rock geochemistry,U-Pb and Hf isotopic study of zircons from diabase swarms in the Xuzhou-Huaibei area of China显示文摘This paper presents a synthetic U-Pb and Hf isotopic study of zircons and a whole-rock geochemical study on diabase swarms that were emplaced into the Proterozoic formations in the Xuzhou-Huaibei area,the southeast margin of North China Craton.Zircons from the diabase dykes display weak oscillatory zoning in the cathodoluminescence(CL) images and show high Th/U ratios(0.91-6.90),both of which are typical of a magmatic origin.The SHRIMP and Q-ICP-MS U-Pb zircon dating results indicate that the diabase swarms were emplaced at ca.890 Ma.Hf isotopic analysis on these zircons gives Hf(t) values ranging from 2.26 to 14.74 and Hf model age t DM1 and t DM2 ranging from 843 to 1321 Ma and from 808 to 1779 Ma,respectively.Geochemically,the diabase swarms are characterized by a relative enrichment in LREE and LILE(Rb,Ba and La),a comparative enrichment in Cr and Ni,but a slight depletement in HFSE(Th,Nb,Ta,Zr and Hf).They are plotted in the within-plate tholeiite series on the tectonic discrimination diagrams.Taken together,these geochemical and isotopic data suggest that the primary magmas to form the diabase dykes in the Xuzhou-Huaibei area could have been derived from a transitional mantle in the Mesoproterozoic,and were most probably emplaced under a continental margin extensional setting at ca.890 Ma.The results of this study demonstrate that the Neoproterozoic(800-900 Ma)magmatism was not restricted to the Yangtze Block,but also occurred at the southeast margin of the North China Craton.WANG QingHai YANG DeBin XU WenLiang 2012Science China Earth Sciences2012,55,9:23
112016 Chinese expert consensus and guidelines for the diagnosis and treatment of papillary thyroid microcarcinoma显示文摘The incidence of papillary thyroid carcinoma(PTC)has exponentially increased in recent years.Papillary thyroid microcarcinoma(PTMC)accounts for the majority of the reported cases of PTC.The debates and crucial issues in PTMC management have received researchers'attention.To further improve the clinical management of PTMC in China,Ming Gao Minghua Ge Qinghai Ji Ruochuan Cheng Hankui Lu Haixia Guan Li Gao Zhuming Guo Tao Huang Xiaoming Huang Xiaoming Li Yansong Lin Qinjiang Liu Xin Ni Yi Pan Jianwu Qin Zhongyan Shan Hui Sun Xudong Wang Zhengang Xu Yang Yu Daiwei Zhao Naisong Zhang ShengZhang Ying Zheng Jingqiang Zhu Dapeng Li Xiangqian Zheng 2017Cancer Biology & Medicine2017,14,3:23
12What Does ChatGPT Say:The DAO from Algorithmic Intelligence to Linguistic Intelligence显示文摘THE well-known ancient Chinese philosopher Lao Tzu(老子)or Laozi(6th~4th century BC during the Spring and Autumn period)started his classic Tao Teh Ching《道德经》or Dao De Jing(see Fig.1)with six Chinese characters:'道(Dao)可(Ke)道(Dao)非(Fei)常(Chang)道(Dao)',which has been traditionally interpreted as“道可道,非常道”or'The Dao that can be spoken is not the eternal Dao'.Fei-Yue Wang Qinghai Miao Xuan Li Xingxia Wang Yilun Lin 2023IEEE/CAA Journal of Automatica Sinica2023,10,3:23
13SHRIMP zircon U-Pb age and significance of Early Paleozoic volcanic rocks in East Kunlun orogenic belt, Qinghai Province, China显示文摘Early Paleozoic volcanic rocks in Nuomuhong area occurred as basalt slice and meta-volcanic slice. SHRIMP zircon U-Pb dating of the basalt slice and the meta-volcanic slice show that the age of the basalt slice is 419±5 Ma, and that of the meta-volcanic slice is 401± 6 Ma. These ages directly testify that there existed Early Paleozoic ocean-continent transform in East Kunlun, the basalt slice was formed in an extensional mid-ocean ridge setting and the meta-volcanic rock slice was formed in an extrusion subduction and collision setting. The inherited zircon age of 1734 Ma in volcanic rocks reflects that the base of East Kunlun may be Middle Proterozoic.ZHU Yunhai1, LIN Qixiang1, JIA Chunxing2 & WANG Guocan1 1.Faculty of Earth Science, China University of Geosciences, Wuhan 430074, China 2.Regional Geological Survey Academy of Qinghai, Xining 800003, China 2006Science China Earth Sciences2006,49,1:20
14Age of Yingfeng rapakivi granite pluton on the north flank of Qaidam and its geological significance显示文摘The Yingfeng rapakivi granite on the north flank of Qaidam is a newly discovered Proterozoic rapakivi pluton in China, which was found after the discovery of Shachang rapakivi in Miyun County, Beijing and Kuandian rapakivi in Jilin Province. Yingfeng rapakivi pluton is ex-posed on the north side of the suture belt between Qinling-Kunlun orogenic belt and North China plate. U-Pb zircon isotopic dating and Ar-Ar isotopic dating of both hornblende and K-feldspar from the Yingfeng rapakivi granite have been conducted. The results show that the age of (1776±33)Ma at the upper intercept in Concorde diagram represents the age of formation of the plu-ton, whereas the age of (526 281) Ma at the lower intercept and Ar-Ar mineral dating of horn-blende and K-feldspar correspond to the age of a later event affecting the pluton, suggesting that Yingfeng pluton has ever been affected by strong regional Caledonian-Hercynian tectonic movement after its formation. The discovery of middle Proterozoic Yingfeng rapakivi granite pro-vides a petrologic evidence for the timing of cratonization of both the continental crust basement in western China and the basement of the North China plate and for a rifting event taking place in the mid-Proterozoic, suggesting that an amalgamation of ancient China continents had ever happened during the L liang Movement?between the early Proterozoic and the mid-Proterozoic.XIAO Qinghui1,2, LU Xinxiang1,3, WANG Fei4, SUN Yangui5, WEI Xiangdong3 & XING Zuoyun6 1. Division of Granite Geology, China Geological Survey, Yichang 443003, China 2. Information Center of Ministry of Land and Resources, Beijing 100812, China 3. Geological Survey of Henan Province and Institute of Geological Research of Henan Province, Zhengzhou 450053, China 4. Geological Institute, China Seismological Bureau, Beijing 100029, China 5. Geological Survey Institute of Qinghai Province, Xining 810032, China 6. China University of Geosciences, Wuhan 430074, China 2004Science China Earth Sciences2004,47,4:20
15Gas Hydrates in the Qilian Mountain Permafrost, Qinghai, Northwest China显示文摘Qilian Mountain permafrost, with area about 10×104 km2, locates in the north of Qinghai-Tibet plateau. It equips with perfect conditions and has great prospecting potential for gas hydrate. The Scientific Drilling Project of Gas Hydrate in Qilian Mountain permafrost, which locates in Juhugeng of Muri Coalfield, Tianjun County, Qinghai Province, has been implemented by China Geological Survey in 2008–2009. Four scientific drilling wells have been completed with a total footage of 2059.13 m. Samples of gas hydrate are collected separately from holes DK-1, DK-2 and DK-3. Gas hydrate is hosted under permafrost zone in the 133–396 m interval. The sample is white crystal and easily burning. Anomaly low temperature has been identified by the infrared camera. The gas hydrate-bearing cores strongly bubble in the water. Gas-bubble and water-drop are emitted from the hydrate-bearing cores and then characteristic of honeycombed structure is left. The typical spectrum curve of gas hydrate is detected using Raman spectrometry. Furthermore, the logging profile also indicates high electrical resistivity and sonic velocity. Gas hydrate in Qilian Mountain is characterized by a thinner permafrost zone, shallower buried depth, more complex gas component and coal-bed methane origin etc.ZHU Youhai ZHANG Yongqin WEN Huaijun LU Zhenquan JIA Zhiyao LI Yonghong LI Qinghai LIU Changling WANG Pingkang GUO Xingwang 2010Acta Geologica Sinica(English Edition)2010,84,1:19
16On the timing of the East Asian summer monsoon maximum during the Holocene Does the speleothem oxygen isotope record reflect monsoon rainfall variability?显示文摘The evolution of the East Asian summer monsoon(EASM) during the Holocene has long been of significant interest.Knowledge of past EASM variability not only increases our understanding of monsoon dynamics on a long timescale,but it also provides an environmental and climatic background for research into Chinese cultural development.However,the timing of the EASM maximum remains controversial.The popular concept of an 'early Holocene maximum' is mainly based on speleothemδ^(18)O(δ^(18)O_c) records from caves in southern China;however,the interpretation of δ^(18)O_C as a reliable proxy for EASM intensity is being increasingly challenged.The present paper is a critical review of the climatic significance of the δ^(18)O_C record from China.Firstly,we suggest that precipitation in northern China is an appropriate index of EASM intensity,the variation of which clearly indicates a mid-Holocene monsoon maximum.Secondly,an interregional comparison demonstrates that the precipitation record in northern China is quite different from that in southern China on a range of timescales,and is inconsistent with the spatial similarity exhibited by speleothem oxygen isotope records.Furthermore,both modeling and observational data show that the δ^(18)O_C records from southern China indeed reflect changes in precipitation δ^(18)O(δ^(18)O_P) rather than precipitation amount,and therefore that their use as an EASM proxy is inappropriate.Finally,we address several significant monsoon-related issues-including the driving mechanism of the EASM on an orbital timescale,the climatic significance of speleothem oxygen isotopes,and the relationship between atmospheric circulation and precipitation in monsoonal regions.CHEN JianHui RAO ZhiGuo LIU JianBao HUANG Wei FENG Song DONG GuangHui HU Yu XU QingHai CHEN FaHu 2016Science China(Information Sciences)2016,59,12:18
17Pollen indication to source plants in the eastern desert of China显示文摘In order to investigate the indication of major pollen types to source plants, 39 surface pollen samples are collected from 39 plant communities. The results show that diversity of pollen assemblages presents in different commu-nities. Chenopodiaceae pollen percentages are highest in Kalidium communities and Ceratoides communities (higher than 45%, average is 63.4%), but high Ephedra pollen per-centages (higher than 3.3%, average is 16.5%)in Ceratoides communities make it distinguished from Kalidium communi-ties. Artemisia pollen percentages (more than 50%) are much higher than Chenopodiaceae (less than 35%) in Artemisia Communities. Nitraria pollen percentages (higher than 2%, average is 13.6%) are highest in Nitraria communities com-pared with those in other community patterns. Tamariceae pollen percentages (higher than 2%, average is 8.6%) are highest both in Tetraena and Reaumuria communities com-pared with those in other community patterns. But in Reau-muria communities, Artemisia pollen percentages are higher than Chenopodiaceae with some other pollen types such as Gramineae, Compositae, Leguminosae; on the contrary, in Tetraena communities, Artemisia pollen percentages are less than Chenopodiaceae with few other pollen types. Calli-gonum pollen only appears in Calligonum communities (higher than 2%,average is 5%). The results of cluster analysis (CLA) and detrended correspondence analysis (DCA) show that the pollen indication to source plants can be reflected by association indices (A), over-representation in-dices (O), under-representation indices (U), R-value, the av-erage pollen percentages where parent plants are absent (Xa) and the average pollen percentages where parent plants are present (Xp). Zygophyllum, Calligonum, Tetraena, Tribulus and Tamariceae can indicate source plants very well, owing to high A scores. Artemisia, Chenopodiaceae and Gramineae have high R-values, and Nitraria, Cruciferae and sedum have high O scores, so they are over-represented types, but the higher Xp and the lower Xa values make that these pollen types can also indicate source plants moderately. Allium, Leguminosae, Roseceae, Pedicularis and Compositae have low A scores (less than 0.5), high O and/or U scores, so they cannot indicate source plants clearly. Some other pollen types, such as Pinus, Picea, Betula, Quercus, Ulmus, Ephedra, Elaegnaceae, Ranunculaceae, Caryophyllaceae, Polygona-ceae, Saxifragaceae, only appear in pollen assemblages, so their indication cannot be decided. Just like the pollen per-centage ratios of Artemisia and Chenopodiaceae (A/C), the ratios of Ephedra and Artemisia (E/A), Nitraria and Ephedra (N/E) can also indicate the aridity of environment. In typical desert communities, A/C ratios are less than 0.5, E/A ratios are more than 0.1, and N/E ratios are less than 1. In steppe desert, A/C ratios are 0.5―2, E/A ratios are less than 0.1, and N/E ratios are more than 1.LI Yuecong XU Qinghai ZHAO Yinclkui YANG Xiaolan XIAO Jule CHEN Hui Lü Xinmiao 2005Chinese Science Bulletin2005,50,15:17
18Relative pollen productivities of typical steppe species in northern China and their potential in past vegetation reconstruction显示文摘The Relative Pollen Productivities(RPPs)of common steppe species are estimated using Extended R-value(ERV)model based on pollen analysis and vegetation survey of 30 surface soil samples from typical steppe area of northern China.Artemisia,Chenopodiaceae,Poaceae,Cyperaceae,and Asteraceae are the dominant pollen types in pollen assemblages,reflecting the typical steppe communities well.The five dominant pollen types and six common types(Thalictrum,Iridaceae,Potentilla,Ephedra,Brassicaceae,and Ulmus)have strong wind transport abilities;the estimated Relevant Source Area of Pollen(RSAP)is ca.1000 m when the sediment basin radius is set at 0.5 m.Ulmus,Artemisia,Brassicaceae,Chenopodiaceae,and Thalictrum have relative high RPPs;Poaceae,Cyperaceae,Potentilla,and Ephedra pollen have moderate RPPs;Asteraceae and Iridaceae have low RPPs.The reliability test of RPPs revealed that most of the RPPs are reliable in past vegetation reconstruction.However,the RPPs of Asteraceae and Iridaceae are obviously underestimated,and those of Poaceae,Chenopodiaceae,and Ephedra are either slightly underestimated or slightly overestimated,suggesting that those RPPs should be considered with caution.These RPPs were applied to estimating plant abundances for two fossil pollen spectra(from the Lake Bayanchagan and Lake Haoluku)covering the Holocene in typical steppe area,using the'Regional Estimates of Vegetation Abundance from Large Sites'(REVEALS)model.The RPPs-based vegetation reconstruction revealed that meadow-steppe dominated by Poaceae,Cyperaceae,and Artemisia plants flourished in this area before 6500–5600 cal yr BP,and then was replaced by present typical steppe.XU QingHai CAO XianYong TIAN Fang ZHANG ShengRui LI YueCong LI ManYue LI Jie LIU YaoLiang LIANG Jian 2014Science China Earth Sciences2014,57,6:13
19Downregulation of serum mi R-17 and mi R-106b levels in gastric cancer and benign gastric diseases显示文摘Altered micro RNA(mi RNA) associated with gastric cancer(GC) development and mi R-17 and mi R-106 b were differentially expressed in GC tissues. This study detected serum levels of mi R-17 and mi R-106 b expression in GC, benign gastric disease(BGD) and healthy controls to assess them as tumor markers for GC. Serum samples from 40 GC, 32 BGD(10 gastric ulcer, 14 gastric polyps, and 8 gastric ulcer with polyps) and 36 healthy individuals were subjected to quantitative reverse transcription polymerase chain reaction(q RT-PCR) analysis of mi R-17 and mi R-106 b expression. The data showed that the serum levels of mi R-17 and mi R-106 b were significantly reduced in healthy individuals and BGD patients compared to GC patients. There was a significant association of mi R-17 and mi R-106 b expression with age, but not with other clinicopathological features, such as gender, tumor differentiation, stage and lymphatic metastasis. Further analysis showed that, in discriminating GC patients from healthy controls, mi R-17 could yield a receiver-operating characteristic(ROC) area under the curve(AUC) of 0.879 with 80.6% sensitivity and 87.5% specificity and mi R-106 b could yield an AUC of 0.856 with 75.0% sensitivity and 92.5% specificity. The combined AUC of mi R-17 and mi R-106 b was 0.913 with 83.3% sensitivity and 87.5% specificity. Collectively, these data suggest that detection of serum mi R-17 and mi R-106 b levels should be further evaluated as novel non-invasive biomarkers in early GC detection and surveillance of disease progression.Qinghai Zeng Cuihong Jin Wenhang Chen Fang Xia Qi Wang Fan Fan Juan Du Yihang Guo Changwei Lin Kaiyan Yang Jingjing Li Xiaowei Peng Xiaorong Li Ke Cao 2014Chinese Journal of Cancer Research2014,26,6:12
20The 3-D non-axisymmetrical Lamb's problem in transversely isotropic saturated poroelastic media显示文摘Based on Biots theory on fluid-saturated porous media, the displacement functions are adopted to convert the 3-D Biots wave equations in the cylindrical coordinate for transversely isotropic saturated poroelastic media into two棗one 6-order and one 2-order棗uncoupling differential governing equations. Then, the differential equations are solved by the Fourier expanding and Hankel integral transform method. Integral solutions of soil skeleton displacements and pore pressure as well as the total stresses for poroelastic media are obtained. Furthermore, the systematic study on Lambs problems for the transversely isotropic saturated poroelastic media is performed. Integral solutions for surface radial, vertical and circumferential displacements are obtained in both cases of drained surface and undrained surface under the vertical and horizontal harmonic excitation force. In the end of this paper, the numerical examples are presented. The calculation results indicate that the difference between the model of isotropic saturated poroelastic media and that of transversely isotropic saturated poroelastic media is obvious.HUANG Yi1 & WANG Xiaogang1,2 1. School of Civil Engineering, Xian University of Architecture & Technology, Xian 710055, China 2. Department of Civil Engineering, Qinghai University, Xining 810016, China Correspondence should be addressed to Huang Yi (email: huangyih@pub.xaonline.com) Received April 15, 2004 revised July 12, 2004 2004Science China(Technological Sciences)2004,47,5:10
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