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| 1 | Geomorphologic 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 | 2004 | Science China Earth Sciences2004,47,9: | 51 |
| 2 | Quantitative 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 | 2007 | Science China Earth Sciences2007,50,4: | 41 |
| 3 | Humid 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 | 2011 | Chinese Science Bulletin2011,56,23: | 28 |
| 4 | Investigation 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. | 2010 | Journal of Environmental Sciences2010,22,5: | 24 |
| 5 | 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 |
| 6 | 2016 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 无 | 2017 | Cancer Biology & Medicine2017,14,3: | 23 |
| 7 | What 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 | 2023 | IEEE/CAA Journal of Automatica Sinica2023,10,3: | 23 |
| 8 | Gas 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 | 2010 | Acta Geologica Sinica(English Edition)2010,84,1: | 19 |
| 9 | Pollen 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 | 2005 | Chinese Science Bulletin2005,50,15: | 17 |
| 10 | Relative 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 | 2014 | Science China Earth Sciences2014,57,6: | 13 |
| 11 | Downregulation 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 | 2014 | Chinese Journal of Cancer Research2014,26,6: | 12 |
| 12 | Surface pollen assemblages of human-disturbed vegetation and their relationship with vegetation and climate in Northeast China显示文摘Pollen assemblages of 53 surface pollen samples from farmlands and wastelands in Northeast China were analyzed. Tree pollen percentages were usually higher than 30%, with Pinus (26.9%), Quercus (0.9%), Betula (0.9%) and Populus (0.7%) as the major types, and herb pollen percentages were usually higher than 50%, with weedy Poaceae (8.7%), Chenopodiaceae (7.1%), Artemisia (1.9%) and Compositae (3.5%) as the major taxa. Thus, the pollen assemblages were consistent with the regional vegetation compositions. However, there were differences in pollen assemblages among regions, especially among different geomorphological units. For example, in the mountains, there were more types of tree pollen and higher total percentages (average 42%) than in other areas, while cereal pollen percentages were lowest (11.2%). In the hills and high plains, herbs made up more than 60% of the pollens, with cereals (average 53.6%) the dominant type. In the low plains, pollen types were similar to those in the hills and high plains, but total pollen concentrations and the proportion of Concentricystes were much higher, while cereal pollen percentages were slightly lower (average 41.6%). Pollen assemblages in different land use types also differed. For example, in farmland, cereal pollen percentages were more than 40% and Chenopodiaceae was usually less than 2.5%, while in wasteland, weedy Poaceae was usually less than 10% and Chenopodiaceae was usually higher than 25%. Total pollen concentrations in farmland (average 3909 grains/g) were much lower than in wasteland (average 15074 grains/g). Redundancy analysis revealed that pollen assemblages were significantly negatively correlated with mean annual temperature (-0.73) and July mean temperature (-0.81) and significantly positively correlated with mean annual precipitation (0.48), indicating that pollen assemblages in the artificial or human-disturbed vegetation reflect regional climate well. Comparison of pollen assemblages in different areas of northern China showed that pollen concentrations reflect the intensities of human impact to some degree. For example, pollen concentrations decrease as human impacts increase in intensity. The cereal pollen proportions in farmland differed by area. In Northeast China, cereal pollen proportions were distinctly higher than in most other areas of northern China, suggesting differences in planting habits and climate. | LI ManYue LI YueCong XU QingHai PANG RuiMing DING Wei ZHANG ShengRui HE ZhiGuo | 2012 | Chinese Science Bulletin2012,57,5: | 10 |
| 13 | Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene显示文摘The Red Earth deposit around Xining, northeastern Tibetan Plateau, has been studied in terms of soil micro-structure, grain-size distribution, major- and trace-element chemistry and magne- tostratigraphy. Field investigations indicate that the Red Earth sequence consists of 25 visually de- finable yellow-brown and weakly-developed soils interbedded with reddish strongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the Chinese Loess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with a negligible sand fraction (>63 μm). Thin-section observations under light microscopy show that the deposit has a clayey texture and the coarse fraction (>10 μm) mainly consists of quartz, feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition of the coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineral grains are semi angular semi-angular and are gener- ally finer than 63 μm. There is a good agreement between the major and minor trace element chem- istry of loess-soil units and the Red Earth deposit. The REE distributions of the loess-soil and the Red Earth deposit are similar in shape, with enriched LREE and fairly flat HREE profiles and a clear nega- tive Eu anomaly. The geochemical characteristics of the Red Earth deposit are also identical to those of upper continental crust, thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the Red Earth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reported Miocene aeolian loess at Qin’an of the Loess Plateau is still unknown. Our results indicate that this aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middle Miocene. The similarity of the element geochem- istry between the Red Earth deposit and the overlying loess shows that they may have similar sources and dynamic transport system, and may indicate that the aridification of the interior of the Tibetan Plateau and central Asia began by at least the middle Miocene. Compared with the last intergla-cial-glacial loess, the grain-size of the Red Earth deposit is finer. This may indicate a lower energy transport agent and/or aridity in the dust source region. However, changes in grain-size and other proxies indicate many climatic fluctuations, with two important shifts at 9.61-9.91 Ma and 7-8 Ma. In addition, the grain-size record shows a shift from a high-frequency and high-amplitude pattern to a low-frequency and low-amplitude pattern at around 10.4 Ma and may indicate a significant environ- mental event at this time. Previous research has shown that the intensity of the southwest Asian monsoon increased at this time, coincident with heavier foraminiferal oxygen isotope values and a sharp fall in sea-level. Thus the environmental event in the Northeast Tibetan Plateau at 10.4 Ma may have global implications. | WANG Xianyan1,7, LU Huayu1,2, JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 2. Department of Urban and Resources Sciences, Nanjing University, Nanjing 210093, China 3. Department of Earth Sciences, Nanjing University, Nanjing 210093, China 4. Department of Geography, Shaanxi Normal University, Xi’an 710062, China 5. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 6 Department of Geography, Qinghai Normal University, Xining 810008, China 7. Graduate School of the Chinese Academy of Sciences, Beijing 100039, China | 2006 | Science China Earth Sciences2006,49,5: | 9 |
| 14 | LHPP inhibits cell growth and migration and triggers autophagy in papillary thyroid cancer by regulating the AKT/AMPK/mTOR signaling pathway显示文摘In recent decades,the incidence rate of papillary thyroid carcinoma(PTC)has been rapidly increasing.However,the molecular mechanism of the physiological and pathological processes of PTC is still largely unknown.Phospholysine phosphohistidine inorganic pyrophosphate phosphatase(LHPP)is a tum or suppressor and exerts anti-tumor effect in several human cancers,while the role and underlying mechanism of LHPP in PTC remain vague.In this study,we firstly evaluated the roles of LHPP in PTC and explored its underlying mechanism.Using clinical tissue samples,we detected the level of LHPP in PTC tissues and in matched adjacent normal tissues.Lower level of LHPP was found in PTC tissues than in matched adjacent normal tissues.Similar LHPP expression pattern was found in PTC cell lines when compared with that in normal human thyroid follicular epithelial cells.Then,we over-expressed LHPP in three PTC cell lines and results showed that ectopic LHPP expression consistently reduced cell viability,proliferation,and migration and triggered cell autophagy.Furthermore,over-expression of LHPP inhibited the activation of the AKT/mTOR pathway and promoted the AMPK signaling pathway.In addition,the activation of AKT/mTOR and inhibition of AMPK signaling pathways restored the role of ectopic LHPP expression in PTC cell lines,indicating that LHPP exerts its anti-tumor activity through regulating the AKT/AMPK/mTOR pathway.Ultimately,we illustrated that ectopic LHPP expression inhibited PTC tumor growth in vivo.In conclusion,we revealed that LHPP has an anti-tumor effect in PTC and indicated that LHPP might serve as an effective diagnostic and therapeutic target for PTC. | Wenyu Sun Kai Qian Kai Guo Lili Chen Jun Xiang Duanshu Li Yi Wu Qinghai Ji Tuanqi Sun Zhuoying Wang | 2020 | Acta Biochimica et Biophysica Sinica2020,52,4: | 8 |
| 15 | Boron isotopic fractionation in laboratory inorganic carbonate precipitation:Evidence for the incorpora-tion of B(OH)_3 into carbonate显示文摘A laboratory inorganic carbonate precipitation experiment at high pH of 8.96 to 9.34 was conducted, and the boron isotopic fractionations of the precipitated carbonate were measured. The data show that boron isotopic fractionation factors (αcarb-3) between carbonate and B(OH)3 in seawater range 0.937 and 0.965, with an average value of 0.953. Our results together with those reported by Sanyal and collabo-rators show that the αcarb-3 values between carbonate and B(OH)3 in solution are not constant but are negatively correlated with the pH of seawater. The measured boron isotopic compositions of carbonate precipitation (δ11Bcarb) do not exactly lie on the best-fit theoretical δ 11B4-pH curves and neither do they exactly parallel any theoretical δ 11B4-pH curves. Therefore, it is reasonable to argue that a changeable proportion of B(OH)3 with pH of seawater should also be incorporated into carbonate except for the dominant incorporation of B(OH)4- in carbonate . Hence, in the reconstruction of the paleo-pH of sea-water from boron isotopes in marine biogenic carbonates, the use of theoretical boron isotopic frac-tionation factor (α4-3) between B(OH)4- and B(OH)3 is not suitable. Instead, an empirical equation should be established. | XIAO YingKai1,2, LI HuaLing1,3, LIU WeiGuo4, WANG XiuFang1 & JIANG ShaoYong5 1 Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008, China 2 State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China 3 Nanjing Institute of Geology and Mineral Resources, Nanjing 210016, China 4 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 5 State Key Laboratory for Mineral Deposits Research, Department of Earth Sciences, Nanjing University, Nanjing 210093, China | 2008 | Science China Earth Sciences2008,51,12: | 8 |
| 16 | Safety and efficacy of stent-assisted coiling for acutely ruptured wide-necked intracranial aneurysms:comparison of LVIS stents with laser-cut stents显示文摘Background:To compare the safety and efficacy of LVIS stent-assisted coiling with those of laser-cut stent-assisted coiling for the treatment of acutely ruptured wide-necked intracranial aneurysms.Methods:Patients with acutely ruptured wide-necked intracranial aneurysms treated with LVIS stent-assisted coiling(LVIS stent group)and laser-cut stent-assisted coiling(laser-cut stent group)were retrospectively reviewed from January 2014 to December 2017.Propensity score matching was used to adjust for potential differences in age,sex,aneurysm location,aneurysm size,neck width,Hunt-Hess grade,and modified Fisher grade.Perioperative procedure-related complications and clinical and angiographic follow-up outcomes were compared.Univariate and multivariate analyses were performed to determine the associations between procedure-related complications and potential risk factors.Results:A total of 142 patients who underwent LVIS stent-assisted coiling and 93 patients who underwent laser-cut stent-assisted coiling were enrolled after 1:2 propensity score matching.The angiographic follow-up outcomes showed that the LVIS stent group had a slightly higher complete occlusion rate and lower recurrence rate than the laser-cut stent group(92.7%vs 80.6%;3.7%vs 9.7%,P=0.078).The clinical outcomes at discharge and follow-up between the two groups demonstrated no significant differences(P=0.495 and P=0.875,respectively).The rates of intraprocedural thrombosis,postprocedural thrombosis,postoperative early rebleeding,and procedure-related death were 0.7%(1/142),1.4%(2/142),2.8%(4/142),and 2.1%(3/142)in the LVIS stent group,respectively,and 4.3%(4/93),2.2%(2/93),1.1%(1/93),and 3.2%(3/93)in the laser-cut stent group,respectively(P=0.082,0.649,0.651,and 0.683).Nevertheless,the rates of overall procedure-related complications and intraprocedural rupture in the LVIS stent group were significantly lower than those in the laser-cut stent group(5.6%vs 14.0%,P=0.028;0.7%vs 6.5%,P=0.016).Multivariate analysis showed that laser-cut stent-assisted coiling was an independent predictor for overall procedurerelated complications(OR=2.727,P=0.037);a history of diabetes(OR=7.275,P=0.027)and other cerebrovascular diseases(OR=8.083,P=0.022)were independent predictors for ischemic complications,whereas none of the factors were predictors for hemorrhagic complications.Conclusions:Compared with laser-cut stent-assisted coiling,LVIS stent-assisted coiling for the treatment of acutely ruptured wide-necked intracranial aneurysms could reduce the rates of overall procedure-related complications and intraprocedural rupture. | Gaici Xue Qiao Zuo Xiaoxi Zhang Haishuang Tang Rui Zhao Qiang Li Yibin Fang Pengfei Yang Bo Hong Yi Xu Qinghai Huang Jianmin Liu | 2021 | Chinese Neurosurgical Journal2021,7,2: | 8 |
| 17 | High-speed silicon photonic Mach–Zehnder modulator at 2 μm显示文摘Recently,2-μm wave band has gained increasing interest due to its potential application for next-generation optical communication.But the development of 2-μm optical communications is substantially hampered by the modulation speed due to the device bandwidth constraints.Thus,a high-speed modulator is highly demanded at 2μm.Motivated by this prospect,we demonstrate a high-speed silicon Mach–Zehnder modulator for a 2-μm wave band.The device is configured as a single-ended push–pull structure with waveguide electrorefraction via the free carrier plasma effect.The modulator was fabricated via a multiproject wafer shuttle run at a commercial silicon photonic foundry.The modulation efficiency of a single arm is measured to be 1.6 V·cm.The high-speed characterization is also performed,and the modulation speed can reach 80 Gbit/s with 4-level pulse amplitude modulation(PAM-4)formats. | Xi Wang Weihong Shen Wenxiang Li Yingjie Liu Yong Yao Jiangbing Du Qinghai Song Ke Xu | 2021 | Photonics Research2021,9,4: | 7 |
| 18 | An unusual isotopic fractionation of boron in synthetic calcium carbonate precipitated from seawater and saline water显示文摘Inorganic calcium carbonate precipitation from natural seawater and saline water at various pH values was carried out experimentally. The results show the clear positive relationships between boron concentration and δ11B of inorganic calcium carbonate with the pH of natural seawater and saline water. However, the variations of boron isotopic fractionation between inorganic calcite and seawater/saline water with pH are inconsistent with the hypothesis that B(OH)4- is the dominant spe-cies incorporated into the biogenic calcite structure. The isotopic fractionation factors α between synthetic calcium carbonate precipitate and parent solutions increase systematically as pH increases, from 0.9884 at pH 7.60 to 1.0072 at pH 8.60 for seawater and from 0.9826 at pH 7.60 to 1.0178 at pH 8.75 for saline water. An unusual boron isotopic fractionation factor of larger than 1 in synthetic calcium carbonate precipitated from seawater/saline water at higher pH is observed, which implies that a substantial amount of the isotopically heavier B(OH)3 species must be incorporated preferentially into synthetic inorganic carbonate. The results propose that the incorporation of B(OH)3 is attributed to the formation of Mg(OH)2 at higher pH of calcifying microenvironment during the synthetic calcium carbonate precipitation. The preliminary experiment of Mg(OH)2 precipitated from artificial seawater shows that heavier 11B is enriched in Mg(OH)2 precipitation, which suggests that isotopically heavier B(OH)3 species incorporated preferentially into Mg(OH)2 precipitation. This result cannot be applied to explain the boron isotopic fractionation of marine bio-carbonate because of the possibility that the unusual environment in this study appears in formation of marine bio-carbonate is infinitesimal. We, however, must pay more attention to this phenomenon observed in this study, which accidentally appears in especially natural environment. | XIAO Yingkai1,2,LI Shizhen1,WEI Haizhen1,SUN Aide1,ZHOU Weijian2 & LIU Weiguo2 1. Qinghai Institute of Salt Lakes,Chinese Academy of Sciences,Xining 810008,China 2. State Key Laboratory of Loess and Quaternary Geology,Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,China | 2006 | Science China Chemistry2006,49,5: | 7 |
| 19 | Pollen flux and vertical dispersion in coniferous and deciduous broadleaved mixed forest in the Changbai Mountains显示文摘The pollen flux in coniferous and deciduous broadleaved mixed forest in the Changbai Mountains is presented in one year's experiments. The results indicate that arboreal pollen percentages are more than 65% and pollen flux is higher than 5000 grain·cm-2·a-1,while less than 2% and lower than 1000 grain·cm-2·a-1 for shrubby pollen,and less than 20% and lower than 3000 grain·cm-1·a-1 for herbaceous pollen for most samples at different heights. The pollen assemblages are similar to those in the samples under 8 m height where Pinus and Ouercus are dominant and followed by the few non-local pollen types,and Fraxinus percentages are high with a few non-local pollen types at 16 m to 32 m height as well as non-local pollen clearly increased at 40 m height. Comparisons between pollen assemblages and vegetation composition suggest that similarities are higher for pollen trap samples than for surface moss samples. | XU QingHai LI YueCong ZHOU LiPing LI YiYin ZHANG ZhenQing LIN FengYou | 2007 | Chinese Science Bulletin2007,52,11: | 6 |
| 20 | Geochemistry and genesis of authigenic pyrite from gas hydrate accumulation system in the Qilian Mountain permafrost, Qinghai, northwest China显示文摘A type of authigenic pyrites that fully fill or semi-fill the rock fractures of drillholes with gas hydrate anomalies are found in the Qilian Mountain permafrost; this type of pyrite is known as 'fracture-filling' pyrite. The occurrence of 'fracture-filling' pyrite has a certain similarity with that of the hydrate found in this region, and the pyrite is generally concentrated in the lower part of the hydrate layer or the hydrate anomaly layer. The morphology, trace elements, rare earth elements, and sulfur isotope analyses of samples from drillhole DK-6 indicate that the 'fracture-filling' pyrites are dominated by cubic ones mainly aligned in a step-like fashion along the surfaces of rock fractures and are associated with a circular structure, lower Co/Ni and Sr/Ba, lower ?REE, higher LREE, significant Eu negative anomalies, and ? 34 SCDT positive bias. In terms of the pyrites' unique crystal morphology and geochemical characteristics and their relationship with the hydrate layers or abnormal layers, they are closely related with the accumulation system of the gas hydrate in the Qilian Mountain permafrost. As climate change is an important factor in affecting the stability of the gas hydrate, formation of fracture-filling pyrites is most likely closely related to the secondary change of the metastable gas hydrate under the regional climate warming. The distribution intensity of these pyrites indicates that when the gas hydrate stability zone(GHSZ) is narrowing, the hydrate decomposition at the bottom of the GHSZ is stronger than that at the top of the GHSZ, whereas the hydrate decomposition within the GHSZ is relatively weak. Thus, the zone between the shallowest and the deepest distribution of the fracture-filling pyrite recorded the largest possible original GHSZ. | WANG PingKang ZHU YouHai LU ZhenQuan HUANG Xia PANG ShouJi ZHANG Shuai JIANG ShaoQing LI QingHai YANG KaiLi LI Bing | 2014 | Science China Earth Sciences2014,57,9: | 6 |