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1Positioning accuracy assessment for the 4GEO/5IGSO/2MEO constellation of COMPASS显示文摘Determined to become a new member of the well-established GNSS family,COMPASS(or BeiDou-2) is developing its capabilities to provide high accuracy positioning services.Two positioning modes are investigated in this study to assess the positioning accuracy of COMPASS' 4GEO/5IGSO/2MEO constellation.Precise Point Positioning(PPP) for geodetic users and real-time positioning for common navigation users are utilized.To evaluate PPP accuracy,coordinate time series repeatability and discrepancies with GPS' precise positioning are computed.Experiments show that COMPASS PPP repeatability for the east,north and up components of a receiver within China's Mainland is better than 2 cm,2 cm and 5 cm,respectively.Apparent systematic offsets of several centimeters exist between COMPASS precise positioning and GPS precise positioning,indicating errors remaining in the treatments of COMPASS measurement and dynamic models and reference frame differences existing between two systems.For common positioning users,COMPASS provides both open and authorized services with rapid differential corrections and integrity information available to authorized users.Our assessment shows that in open service positioning accuracy of dual-frequency and single-frequency users is about 5 m and 6 m(RMS),respectively,which may be improved to about 3 m and 4 m(RMS) with the addition of differential corrections.Less accurate Signal In Space User Ranging Error(SIS URE) and Geometric Dilution of Precision(GDOP) contribute to the relatively inferior accuracy of COMPASS as compared to GPS.Since the deployment of the remaining 1 GEO and 2 MEO is not able to significantly improve GDOP,the performance gap could only be overcome either by the use of differential corrections or improvement of the SIS URE,or both.ZHOU ShanShi CAO YueLing ZHOU JianHua HU XiaoGong TANG ChengPan LIU Li GUO Rui HE Feng CHEN JunPing WU Bin 2012Science China(Physics,Mechanics & Astronomy)2012,55,12:31
2Early tectonic uplift of the northern Tibetan Plateau显示文摘The Hexi Corridor is the northmost foreland basin of the Tibetan Plateau and its formation is controlled by the northern marginal fault of Tibet, Altyn Tagh Fault (ATF)-North Qilian Shan marginal Fault (NQF), and the southern Kuantan Shan-Longshou Shan Fault (KLF). So its study is important to understanding the mechanism of Tibet formation and its influence on global climate change. The oldest Cenozoic sediments in the Corridor is the Huoshaogou Formation which consists of terrigenous fine conglomerate, sandstone, sandy mudstone and mudstone, depositing in alluvial to lacustrine and fan delta sedimentary environments. Detailed paleomagnetic measurements of this sequence at Yumen clearly reveal eleven pairs of normal and reversed polarities. Fossil mammals found around the section support that most of the observed polarities can be well correlated with chrons between 13n and 18r of the standard geomagnetic polarity time scale, yielding ages of 40.2-33.35 Ma. The mean declinations of this sequence and its immediately above stratigraphy indicate an 18.3° rapid clockwise rotation of the Hexi Corridor. Since this sequence has been strongly folded and is capped by an angular unconformity, we think that the presence of the thick alluvial fan conglomeration at the bottom of the foreland basin may indicate the initial deformation and uplift of the northern Qilian Shan. This process could occur at latest at 40.2 Ma, driven by the faults NQF and KLF that thrust onto the Hexi corridor respectively from its southern and northern margins. These faults are in an early response to the collision of India with Asia, while the unconformable termination and rotation of the Huoshaogou Formation at ~33.35 Ma indicate other early episode of rapid tectonic deformation and uplift of the northern Tibet.DAI Shuang FANG Xiaomin SONG Chunhui GAO Junping GAO Donglin LI Jijun 2005Chinese Science Bulletin2005,50,15:30
3Bronchial Artery Embolization for Hemoptysis: A Retrospective Observational Study of 344 Patients显示文摘Hongxia Shao Junping Wu Qi Wu Xin Sun Li Li Zhiheng Xing Hongfen Sun 2015Chinese Medical Journal2015,,1:20
4Mapping the hotspots and coldspots of ecosystem services in conservation priority setting显示文摘空间明确地热点和 coldspots 印射是在将保存放为生态系统服务(ES ) 的优先级的一个重要连接。然而,很少研究都没识别并且测试了他们的 ES 热点和 coldspots 的紧密和效率,它可以削弱生态的保存的有效性。在这学习,基于 RUSLE 模型和 Getis-Ord 官方补给 * 统计,我们确定了年度土壤保存服务(SC ) 的变化并且从 2000 ~ 2013 在中国的 Shaanxi 省识别了统计上重要的热点和 coldspots。结果显示那, 1 ) 有高 SC 的区域也介绍了一个显著地增加的趋势,当有低 SC 的区域仅仅稍微变化了时;2 ) SC 热点和 coldspots 证明热点主要是的明显的空间 differentiationthe 空间地在南部的 Shaanxi 聚集了,当 coldspots 主要在 Guanzhong 盆和沙多风的高原被散布时;并且 3 ) 识别热点有提供 SC 的最高的能力,与提供的 29.6% 全部的区域, 59.7% 总数满足。相反, coldspots 占据了 46.3% 全部的区域,但是仅仅提供了 17.2% 全部的 SC。除了保存单个 ES, Getis-Ord 官方补给 * 统计方法能也帮助为保存多重 ES 和生物多样性识别多功能的优先级区域。LI Yingjie ZHANG Liwei YAN Junping WANG Pengtao HU Ningke CHENG Wei FU Bojie 2017Journal of Geographical Sciences2017,27,6:19
5High precision topographic data on Lop Nor basin's Lake 'Great Ear' ? and the timing of its becoming a dry salt lake显示文摘High precision elevation measurements using DGPS were carried out along three representative tran- sects for the 'Great Ear' area, a dry salt lake within the Lop Nor basin. Results indicate that the Lop Nor basin is only 5.2 m deep and its lowest point occurs at the center of the 'Great Ear'. In addition, the basin is asymmetric - steeper in the southwest (0.19‰) and gentler in the northeast (0.09‰). Points along the same 'Great Ear' ring were found to have an identical elevation value, but different when from different ones (lower towards the center). The spacing of the 'Great Ear' rings was found to be closely related with the surface steepness. The closer the 'Great Ear' rings are spaced, the steeper the ground surface, and vice versa. These findings support the argument that the 'Great Ear' rings are the former shoreline trails left behind by Lop Nor water during the last few episodes of recession towards its total dry up. A comprehensive analysis of the high precision elevation data, historical accounts, aerial and satellite photographs and imagery, and official topographic maps of the study area suggests that the 'Great Ear' area in the Lop Nor basin was incorrectly mapped as being covered by a great body of water on the 1963 topographic maps. A re-interpretation of the 1958 aerial photographs and newer remote sensing imagery indicated that the 'Great Ear' ring structure was already in place in 1958 and it continued to appear on the subsequent remote sensing data without any major changes. It is estimated that lake water in the 'Great Ear' area of the Lop Nor basin disappeared between the late 1930s and early 1940s.LI BaoGuo MA LiChun JIANG PingAn DUAN ZengQiang SUN DanFeng QIU HongLie ZHONG JunPing WU HongQi 2008Chinese Science Bulletin2008,53,6:11
6Apatite Fission Track Evidence of Uplift Cooling in the Qiangtang Basin and Constraints on the Tibetan Plateau Uplift显示文摘The Qiangtang basin is located in the central Tibetan Plateau. This basin has an important structural position,and further study of its tectonic and thermal histories has great significance for understanding the evolution of the Tibetan Plateau and the hydrocarbon potential of marine carbonates in the basin. This study focuses on low temperature thermochronology and in particular conducted apatite fission track analysis. Under constraints provided by the geological background,the thermal history in different tectonic units is characterized by the degree of annealing of samples,and the timing of major(uplift-erosion related) cooling episodes is inferred. The cooling history in the Qiangtang basin can be divided into two distinct episodes. The first stage is mainly from the late Early Cretaceous to the Late Cretaceous(69.8 Ma to 108.7 Ma),while the second is mainly from the MiddleLate Eocene to the late Miocene(10.3 Ma to 44.4 Ma). The first cooling episode records the uplift of strata in the central Qiangtang basin caused by continued convergent extrusion after the BangongNujiang ocean closed. The second episode can be further divided into three periods,which are respectively 10.3 Ma,22.6–26.1 Ma and 30.8–44.4 Ma. The late Oligocene-early Miocene(22.6–26.1 Ma) is the main cooling period. The distribution and times of the earlier uplift-related cooling show that the effect of extrusion after the collision between Eurasian plate and India plate obviously influenced the Qiangtang basin at 44.4 Ma. The Qiangtang basin underwent compression and started to be uplifted from the middle-late Eocene to the early Oligocene(45.0–30.8 Ma). Subsequently,a large-scale and intensive uplift process occurred during the late Oligocene to early Miocene(26.1–22.6 Ma) and the basin continued to undergo compression and uplift up to the late Miocene(10.3 Ma). Thus,uplift-erosion in the Qiangtang basin was intensive from 44.5 Ma to about 10 Ma. The timing of cooling in the second episode shows that the uplift of the Qiangtang basin was caused by the strong compression after the collision of the Indian plate and Eurasian plate. On the whole,the new apatite fission-track data from the Qiangtang basin show that the Tibetan Plateau started to extrude and uplift during 45–30.8 Ma. The main period of uplift and formation of the Tibetan Plateau took place about 22.6–26.1 Ma,and uplift and extrusion continued until the late Miocene(10.3 Ma).REN Zhanli CUI Junping LIU Chiyang LI Tiejun CHEN Gang DOU Shuang TIAN Tao LUO Yating 2015Acta Geologica Sinica(English Edition)2015,89,2:11
7Terrace dating as an archive of the run-through of the Sanmen Gorges显示文摘Analysis of morphological properties in the Sanmen Gorges region of the Yellow River shows that four river terraces have been developed at the entrance to the gorges. Commonly, thick aeolian loess-paleosol sequence was deposited on the terraces, which makes it easy to date the terraces. The dating of paleomagnetic, loess-paleosol sequence matching and thermoluminescence show that terraces T2, T3 and T4 were formed 0. 129 Ma, 0. 625 Ma and 0. 865 Ma ago, respectively. The formation of these terraces in this region indicates that the Yellow River has experienced four intensive downcutting events during the last 0.9 Ma. The Yellow River cut through the Sanmen Gorges and inpoured into the East China Sea no later than 0. 865 Ma.PAN Baotian WANG Junping GAO Hongshan CHEN Yingying LI Jijun LIU Xiaofeng 2005Progress in Natural Science:Materials International2005,15,12:9
8An Ethylene-inhibited NF-YC Transcription Factor RhNF-YC9 Regulates Petal Expansion in Rose显示文摘The speed of flower opening is closely related to their ornamental period.Ethylene functions as a negative regulator involved in the regulation of the petal expansion process.In this study,we isolated a NF-YC transcription factor gene,RhNF-YC9,fromrose petals.RhNF-YC9 expression was induced at the early stages of flower opening but was inhibited by ethylene treatment.Silencing RhNF-YC9 decreased the speed of petal expansion from stage 2 to stage 5.The expressions of 11 cell expansion-related genes involved in cell wall loosening,cell turgor modulation,and cytoskeleton remodeling were significantly down-regulated in RhNF-YC9-silenced petals.We also found that silencing RhNF-YC9 decreased the expression of gibberellin acid(GA)biosynthetic gene RhGA20ox while significantly increasing the transcripts of GA catabolic gene RhGA2ox,reducing the accumulation of GA4 and GA7.The influence of ethylene treatment on the expression of RhGA20ox and RhGA2ox showed the same trend.These results together suggested that RhNF-YC9 positively regulated the speed of petal expansion and mediated the crosstalk between ethylene and GA.Our findings revealed a new insight into the function of NF-YC transcription factors involved in ethylene-regulated petal expansion.Changxi Chen Nisar Hussain Yaru Wang Mingtong Li Lin Liu Meizhu Qin Nan Ma Junping Gao Xiaoming Sun 2020Horticultural Plant Journal2020,6,6:9
9Targeting autophagy using small-molecule compounds to improve potential therapy of Parkinson’s disease显示文摘Parkinson’s disease(PD),known as one of the most universal neurodegenerative diseases,is a serious threat to the health of the elderly.The current treatment has been demonstrated to relieve symptoms,and the discovery of new small-molecule compounds has been regarded as a promising strategy.Of note,the homeostasis of the autolysosome pathway(ALP)is closely associated with PD,and impaired autophagy may cause the death of neurons and thereby accelerating the progress of PD.Thus,pharmacological targeting autophagy with small-molecule compounds has been drawn a rising attention so far.In this review,we focus on summarizing several autophagy-associated targets,such as AMPK,m TORC1,ULK1,IMPase,LRRK2,beclin-1,TFEB,GCase,ERRα,C-Abelson,and as well as their relevant small-molecule compounds in PD models,which will shed light on a clue on exploiting more potential targeted small-molecule drugs tracking PD treatment in the near future.Kai Zhang Shiou Zhu Jiamei Li Tingting Jiang Lu Feng Junping Pei Guan Wang Liang Ouyang Bo Liu 2021Acta Pharmaceutica Sinica B2021,11,10:9
10The biological effect of metal ions on the granulation of aerobic granular activated sludge显示文摘As a special biofilm structure,microbial attachment is believed to play an important role in the granulation of aerobic granular activated sludge(AGAS).This experiment was to investigate the biological effect of Ca^(2+),Mg^(2+),Cu^(2+),Fe^(2+),Zn^(2+),and K+which are the most common ions present in biological wastewater treatment systems,on the microbial attachment of AGAS and flocculent activated sludge(FAS),from which AGAS is always derived,in order to provide a new strategy for the rapid cultivation and stability control of AGAS.The result showed that attachment biomass of AGAS was about 300%higher than that of FAS without the addition of metal ions.Different metal ions had different effects on the process of microbial attachment.FAS and AGAS reacted differently to the metal ions as well,and in fact,AGAS was more sensitive to the metal ions.Specifically,Ca^(2+),Mg^(2+),and K+could increase the microbial attachment ability of both AGAS and FAS under appropriate concentrations,Cu^(2+),Fe^(2+),and Zn^(2+)were also beneficial to the microbial attachment of FAS at low concentrations,but Cu^(2+),Fe^(2+),and Zn^(2+)greatly inhibited the attachment process of AGAS even at extremely low concentrations.In addition,the acylated homoserine lactone(AHL)-based quorum sensing system,the content of extracellular polymeric substances and the relative hydrophobicity of the sludges were greatly influenced by metal ions.As all these parameters had close relationships with the microbial attachment process,the microbial attachment may be affected by changes of these parameters.Wen Hao Yaochen Li Junping Lv Lisha Chen Jianrong Zhu 2016Journal of Environmental Sciences2016,28,6:8
11Mutation profile and its correlation with clinicopathology in Chinese hepatocellular carcinoma patients显示文摘Background:Hepatocellular carcinoma(HCC)is one of the most common causes of cancer worldwide.Although many studies have focused on oncogene characteristics,the genomic landscape of Chinese HCC patients has not been fully clarified.Methods:A total of 165 HCC patients,including 146 males and 19 females,were enrolled.The median age was 55 years(range,27-78 years).Corresponding clinical and pathological information was collected for further analysis.A total of 168 tumor tissues from these patients were selected for next-generation sequencing(NGS)-based 450 panel gene sequencing.Genomic alterations including single nucleotide variations(SNV),short and long insertions and deletions(InDels),copy number variations,and gene rearrangements were analyzed.Tumor mutational burden(TMB)was measured by an algorithm developed in-house.The top quartile of HCC was classified as TMB high.Results:A total of 1,004 genomic alterations were detected from 258 genes in 168 HCC tissues.TMB values were identified in 160 HCC specimens,with a median TMB of 5.4 Muts/Mb(range,0-28.4 Muts/Mb)and a 75%TMB of 7.7 Muts/Mb.The most commonly mutated genes were TP53,TERT,CTNNB1,AXIN1,RB1,TSC2,CCND1,ARID1A,and FGF19.SNV was the most common mutation type and C:G>T:A and guanine transformation were the most common SNVs.Compared to wild-type patients,the proportion of Edmondson grade III-IV and microvascular invasion was significantly higher in TP53 mutated patients(P<0.05).The proportion of tumors invading the hepatic capsule was significantly higher in TERT mutated patients(P<0.05).The proportion of Edmondson grade I-II,alpha fetoprotein(AFP)<25μmg/L,and those without a history of hepatitis B was significantly higher in CTNNB1 mutated patients(P<0.05).CTNNB1 mutations were associated with TMB high in HCC patients(P<0.05).Based on correlation analysis,the mutation of TP53 was independently correlated with microvascular invasion(P=0.002,OR=3.096)and Edmondson grade III-IV(P=0.008,OR=2.613).The mutation of TERT was independently correlated with tumor invasion of the liver capsule(P=0.001,OR=3.030),and the mutation of CTNNB1 was independently correlated with AFP(<25μmg/L)(P=0.009,OR=3.414).Conclusions:The most frequently mutated genes of HCC patients in China were TP53,TERT,and CTNNB1,which mainly lead to the occurrence and development of HCC by regulating the P53 pathway,Wnt pathway,and telomere repair pathway.There were more patients with microvascular invasion and Edmondson III-IV grade in TP53 mutated patients and more patients with hepatic capsule invasion in TERT mutated patients,while in CTNNB1 mutated patients,there were more patients with Edmondson I-II grade,AFP<25μmg/L,and a non-hepatitis B background.Also,the TMB values were significantly higher in CTNNB1 mutated patients than in wild type patients.Shuo Wang Huasheng Shi Tao Liu Manjiang Li Sanshun Zhou Xuan Qiu Zusen Wang Weiyu Hu Weidong Guo Xiaoqian Chen Honglin Guo Xiaoliang Shi Junping Shi Yunjin Zang Jingyu Cao Liqun Wu 2021Hepatobiliary Surgery and Nutrition2021,10,2:8
12RNA interference targeting CD147 inhibits metastasis and invasion of human breast cancer MCF-7 cells by downregulating MIVIP-9/VEGF expression显示文摘Fang Li Junping Zhang Jiqiang Guo Yuan Jia Yaping Han Zhuanhua Wang 2018Acta Biochimica et Biophysica Sinica2018,50,7:7
13Performance and role of N-acyl-homoserine lactone(AHL)-based quorum sensing(QS) in aerobic granules显示文摘The present study investigated the relationship between N-acyl-homoserine lactone(AHL)-based quorum sensing(QS) and the physico-chemical properties of aerobic granules.Stable mature granules were observed in SBR2 and SBR3 with average diameters of 0.96,and1.49 mm,respectively. The sludge densities of aerobic granules in SBR2 and SBR3 were1.0246,and 1.0201 g/mL,respectively,which were higher than that of flocculent sludge in SBR1(1.0065 g/mL). The results showed that the activity of AHL-based QS in SBR2 and SBR3 amounted to 2.4- and 2.1-fold induction,however,that in SBR1 with flocculent sludge was1.6-fold induction. In addition,the results also showed that the activity of AHL-based QS in the three reactors rose in the feast condition,and then dropped with the consumption of substrate. However,the activity of AHL-based QS in these three reactors recovered again in prolonged starvation. Furthermore,the results showed that the enhancement of AHL-based QS favored the extracellular polymeric substance production of microorganisms in activated sludge. Thus,it could be concluded that aerobic granules showed higher AHL-based QS than flocculent sludge,which resulted from the higher sludge density of aerobic granules than flocculent sludge. AHL-based QS was related to the metabolism energy in the feast condition; however,in prolonged starvation,microorganisms would emit more AHL-like molecules to protect themselves to resist starvation. Moreover,the enhancement of AHL-based QS favored the EPS component productivity of the microorganisms in activated sludge,which contributed to maintain the aerobic granular structure.Yaochen Li Junping Lv Chen Zhong Wen Hao Yaqin Wang Jianrong Zhu 2014Journal of Environmental Sciences2014,26,8:6
14Instability characteristics of the East Asian Monsoon recorded by high-resolution loess sections from the last interglacial (MIS5)显示文摘The selection of high-resolution loess sections is needed in order to determine the climatic variability of the East Asian Monsoon during the last interglacial. Two sequences of S1 on the eastern and west-ern sides of the Liupan Mountain were both composed of five paleosol layers and four loess layers,indicating that there were five strong summer monsoon events and four strong winter monsoon events in MIS5. This corresponds with other records of the East Asian Monsoon,along with NGRIP and the North Atlantic records,implying that the climate of the Northern Hemisphere was very instable during the last interglacial. Two layers of paleosols and one layer of loess had developed during MIS5a and MIS5c. Compared with MIS5e,the climate in MIS5a and MIS5c fluctuated more intensively on a millen-nial scale,whereas the climate was relatively stable in MIS5e.GUAN QingYu PAN BaoTian GAO HongShan LI BingYuan WANG JunPing SU Huai 2007Science China Earth Sciences2007,50,7:5
15Robust L_2-L_∞ control for uncertain singular systems with time-varying delay显示文摘We study the problem of L2-L1 control for a class of uncertain singular systems with time-delay and norm-bounded parameter uncertainties in this paper. A new delay-dependent robust stability criterion is obtained in terms of linear matrix inequalities (LMIs). Based on this criterion, a state feedback controller is designed to guarantee that the closed-loop system is regular, impulse free and stable with a prescribed L2-L1 performance satisfied for all admissible parameter uncertainties. A simulation example is included to illustrate the effectiveness of the proposed method.Lin Li Yingmin Jia Junping Du Shiying Yuan 2008Progress in Natural Science:Materials International2008,18,8:5
16Danggui-shaoyao-san, a traditional Chinese medicine prescription, alleviates the orthodontic pain and inhibits neuronal and microglia activation显示文摘Li Hongshi Gu Zexu Wu Li'an Xia Liang Zhou Kecheng E Lingling Wang Dongsheng Kou Junping Liu Hongchen 2014Chinese Medical Journal2014,,20:4
17Visible and Infrared Video Fusion Using Uniform Discrete Curvelet Transform and Spatial-Temporal Information显示文摘Multiple visual sensor fusion provides an effective way to improve the robustness and accuracy of video surveillance system. Traditional video fusion methods fuse the source videos using static image fusion methods frame-by-frame without considering the information in temporal dimension. The temporal information can't be fully utilized in fusion procedure. Aiming at this problem, a visible and infrared video fusion method based on Uniform discrete curvelet transform(UDCT) and spatial-temporal information is proposed. The source videos are decomposed by using UDCT, and a set of local spatial-temporal energy based fusion rules are designed for decomposition coefficients. In these rules, we consider the current frame's coefficients and the coefficients on temporal dimension which are the coefficients of adjacent frames. Experimental results demonstrated that the proposed method works well and outperforms comparison methods in terms of temporal stability and consistency as well as spatial-temporal information extraction.LI Qingping DU Junping XU Liang 2015Chinese Journal of Electronics2015,24,4:4
18Clinical impact and mechanisms of hepatitis B virus infection concurrent with non-alcoholic fatty liver disease显示文摘Chronic hepatitis B(CHB)virus infection is an important threat to global health despite the administration of vaccines and the use of antiviral treatments.In recent years,as the prevalence of obesity and metabolic syndrome has increased,non-alcoholic fatty liver disease(NAFLD)in patients with CHB has become more common.Both diseases can lead to liver fibrosis and even hepatocellular carcinoma,but the risk of dual etiology,outcome,and CHB combined with NAFLD is not fully elucidated.In this review,we assess the overlapping prevalence of NAFLD and CHB,summarize recent studies of clinical and basic research related to potential interactions,and evaluate the progressive changes of treatments for CHB patients with NAFLD.This review increases the understanding of the relationship and mechanisms of interaction between steatosis and hepatitis B virus infection,and it provides new strategies for the future clinical management and treatment of CHB combined with NAFLD.Xin Tong Yu Song Shengxia Yin Jian Wang Rui Huang Chao Wu Junping Shi Jie Li 2022Chinese Medical Journal2022,,14:4
19Markov branching processes with immigration-migration and resurrection显示文摘We consider a modified Markov branching process incorporating with both state-independent immigration-migration and resurrection. The effect of state-independent immigration-migration is firstly in- vestigated in detail. The explicit expressions for the extinction probabilities and mean extinction times are presented. The ergodicity and stability properties of the process incorporating with resurrection structure are then investigated. The conditions for recurrence, ergodicity and exponential ergodicity are obtained. An explicit expression for the equilibrium distribution is also presented. As a preparation, the criteria for regularity and uniqueness for such structure are firstly established.LI JunPing LIU ZaiMing 2011Science China Mathematics2011,54,5:4
20Response of grain size of Quaternary gravels to climate and tectonics in the northern Tibetan Plateau显示文摘The widely distributed thick gravel deposits along the rim of the Tibetan Plateau have been long thought to be the product of rapid tectonic uplift of the plateau. However, this has been challenged by recent works that suggest these thick gravels may be the result of climate change. In this paper we carried out a detailed field measurement of gravel grain sizes from the Jiuquan and Gobi Gravel Beds in the top of the Laojunmiao section in the Jiuxi Basin in the northern margin of Qilian Mts. (northern Tibetan Plateau). The results suggest that the grain sizes of the Jiuquan and Gobi Gravel Beds over the last 0.8 Ma are characterized by nine coarse-fine cycles having strong 100-ka and 41-ka periodicities that correlate well with the loess-paleosol monsoon record and isotopic global climatic record from deep sea sediments as well as by a long trend of coarsening in gravel grain size. The coarse gravel layers were formed during the warm-humid interglaciations while the fine layers correspond to the cold-dry glaciations. Because the paleoclimate in NW China began to get dramatically drier after the mid-Pleistocene, we think the persistent coarsening of gravel grain size was most probably caused by the rapid uplift of the northern Tibetan Plateau, and that the orbital scale cyclic variations in gravel grain size were driven by orbital forcing factors that were superimposed on the tectonically-forced long-term coarsening trend in gravel size. These findings also shed new light on the interaction results of climate and tectonics in relation to the uplift of the Tibetan Plateau.FU KaiDao FANG XiaoMin GAO JunPing HAN WenXia LI LiLi 2007Science China Earth Sciences2007,50,1:3
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