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| 1 | 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 |
| 2 | Discovery 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 process | Wenliang Xu Dongyan Wang Xiaochun Liu Qinghai Wang Jingqian Lin | 2002 | Chinese Science Bulletin2002，47，14： | 37 |
| 3 | SHRIMP 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 | 2005 | Science China Earth Sciences2005，48，2： | 32 |
| 4 | 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 |
| 5 | Neoproterozoic 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 | 2012 | Science China Earth Sciences2012，55，9： | 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 | On 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 | 2016 | Science China(Information Sciences)2016，59，12： | 18 |
| 8 | 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 |
| 9 | 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 |
| 10 | 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 |
| 11 | 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 |
| 12 | 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 |
| 13 | 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 |
| 14 | A novel procedure for pollen-based quantitative paleoclimate reconstructions and its application in China显示文摘Traditionally, the evaluation of pollen-based quantitative paleoclimate reconstructions focuses on the ability of calibration sets to infer present climatic conditions and/or the similarity between fossil and modern assemblages. Objective criteria for choosing the most appropriate climate parameter(s) to be reconstructed at a specific site are thus lacking. Using a novel approach for testing the statistical significance of a quantitative reconstruction using random environmental data, in combination with the advantageous large environmental gradients, abundant vegetation types and comprehensive modern pollen databases in China, we describe a new procedure for pollen-based quantitative paleoclimatic reconstructions. First, the most significant environmental variable controlling the fossil pollen assemblage changes is identified. Second, a calibration set to infer changes in this targeted variable is built up, by limiting the modern ranges of other environmental variables. Finally, the pollen-based quantitative reconstruction is obtained and its statistical significance assessed. This novel procedure was used to reconstruct the mean annual precipitation(Pann) from Gonghai Lake in the Lvliang Mountains, and Tianchi Lake in the Liupan Mountains, on the eastern and western fringe of the Chinese Loess Plateau, respectively. Both Pann reconstructions are statistically significant(p<0.001), and a sound and stable correlation relationship exists in their common period, showing a rapid precipitation decrease since 3300 cal yr BP. Thus, we propose that this procedure has great potential for reducing the uncertainties associated with pollen-based quantitative paleoclimatic reconstructions in China. | CHEN JianHui LV FeiYa HUANG XiaoZhong H.John B.BIRKS Richard J.TELFORD ZHANG ShengRui XU QingHai ZHAO Yan WANG HaiPeng ZHOU AiFeng HUANG Wei LIU JianBao WEI GuoYing | 2017 | Science China Earth Sciences2017，60，11： | 6 |
| 15 | Surface pollen assemblages as indicators of human impact in the warm temperate hilly areas of eastern China显示文摘Investigation of 78 surface pollen samples from warm temperate hilly areas of eastern China shows that pollen assemblages in areas of different land use are significantly different.Pollen concentrations in wastelands are higher than in plantations;these,in turn,are higher than in farmlands;implying that pollen concentration decreases with increasing human impact.Arboreal pollen dominated by Pinus and Quercus is common in all samples.Herbaceous pollen percentages are higher while shrub pollen,fern spores and fern allies are lower in farmlands than in wastelands.Crop pollen is only detectable in and near farmlands;its percentages and concentrations decrease in wastelands.Cereal and Cruciferae pollen percentages average 16.7% and 6.7% in farmland respectively,but Cereal reduces to less than 3% and Cruciferae to less than 0.5% in nearby wastelands.Principle coordinates analysis and clustering analysis indicate that pollen assemblages from farmlands are distinguishable from those under other vegetation types.Occurrence of Poaceae,Chenopodiaceae,Artemisia,and Compositae pollen and Selaginella sinensis spores are closely related to human activities,and their types and frequencies indicate intensity of human impact.The spatial distribution of crops,Chenopodiaceae,and Artemisia reflects changes in both natural environments and human activities.Percentages of cereal and Cruciferae pollen,for example,increase with decreasing altitude,but decrease with increasing latitude.Understanding pollen assemblages under artificial and human-disturbed vegetation in hilly areas may aid understanding of human impacts on the plains during the early-middle Holocene. | DING Wei PANG RuiMing XU QingHai LI YueCong CAO XianYong | 2011 | Chinese Science Bulletin2011，56，10： | 6 |
| 16 | Surface pollen and its relationship to vegetation on the southern slope of the eastern Qilian Mountains显示文摘The objective of this study is to investigate pollen-vegetation relationship in the Qilian Mountains. The eastern Qilian Mountains are located in the transitional zone of the Tibetan Plateau, the Loess Plateau and the arid region of Northwest China, which is one of the key areas of global environmental change. A total of 13 surface pollen samples from main vegetation have been collected. Pollen percentages were calculated in all samples. In order to reveal the relationship between pollen composition and the vegetation types from which the soil samples have been collected, Detrended Correspondence Analysis (DCA) ordination method was employed on the pollen data. The results show that dominating vegetation types can be recognized by their pollen spectra: Picea crassifolia forest, alpine shrub and alpine meadow as well. Altitude and temperature determine the distribution of the surface pollen and the vegetation. The good agreement between modern vegetation and surface samples across this area provides a measure of the reliability of using pollen data to reconstruct paleoenvironment and paleovegetation patterns in this or other similar regions. However the loss of Betula pollen in forest needs further investigation. Pollen oxidation is the most important factor contributing to the damage of modern pollen in the study area. Pollen concentrations decrease with the increase of pH values of soils, and decrease sharply when the pH exceeds 7.6. | LU Xinmiao CHEN Hui XU Qinghai | 2006 | Journal of Geographical Sciences2006，16，2： | 4 |
| 17 | Spatial patterns of vegetation and climate in the North China Plain during the Last Glacial Maximum and Holocene climatic optimum显示文摘Reconstructing the spatial patterns of regional climate and vegetation during specific intervals in the past is important for assessing the possible responses of the ecological environment under future global warming scenarios. In this study, we reconstructed the history of regional vegetation and climate based on six radiocarbon-dated pollen records from the North China Plain. Combining the results with existing pollen records, we reconstruct the paleoenvironment of the North China Plain during the Last Glacial Maximum(LGM) and the Holocene Climatic Optimum(HCO). The results show that changes in the regional vegetation since the LGM were primarily determined by climatic conditions, the geomorphic landscape and by human activity.During the LGM, the climate was cold and dry;mixed broadleaf-coniferous forest and deciduous-evergreen broadleaf forest developed in the southern mountains, and cold-resistant coniferous forest and mixed broadleaf-coniferous forest were present in the northern mountains. The forest cover was relatively low, with mesophytic and hygrophilous meadow occupying the southern part of the plain, and temperate grassland and desert steppe were distributed in the north;Chenopodiaceae-dominated halophytes grew on the exposed continental shelf of the Bohai Sea and Yellow Sea. During the HCO, the climate was warm and wet;deciduous broadleaf forest and deciduous-evergreen broadleaf forest, with subtropical species, developed in the southern mountains, and deciduous broadleaf forest with thermophilic species was present in northern mountains. Although the degree of forest cover was greater than during the LGM, the vegetation of the plain area was still dominated by herbs, while halophytes had migrated inland due to sea level rise. In addition, the expansion of human activities, especially the intensification of cultivation,had a significant influence on the natural vegetation. Our results provide data and a scientific basis for paleoclimate modelling and regional carbon cycle assessment in north China, with implications for predicting changes in the ecological environment under future global warming scenarios. | Manyue LI Shengrui ZHANG Qinghai XU Jule XIAO Ruilin WEN | 2019 | Science China Earth Sciences2019，62，8： | 4 |
| 18 | 2017 Chinese expert consensus on the clinical application ofserum marker for thyroid cancer显示文摘In recent years, the clinical incidence of thyroid cancer has been increasing year by year, and its risk assessment and clinical management methods have also been accordingly modified and constantly improved. There are great differences between the clinical diagnostic and therapeutic modes and disease management of thyroid cancer employed by various medical institutions in China, particularly with regard to the clinical application of serum marker of thyroid cancer. To this end, the China Anti-Cancer Association Thyroid Cancer Specialized Committee Chinese Association of Thyroid Oncology organized this compilation of ExpertConsensus on Clinical Application of Serum Marker of Thyroid Cancer to help and impel relevant clinical institutions and professionals to standardize clinical diagnosis, treatment, and long-term management of thyroid cancer, and to properly utilize the serum marker for scientific auxiliary clinical diagnosis and assessment of thyroid cancer before and after operation. | Ming Gao Minghua Ge Qinghai Ji Ruochuan Cheng Hankui Lu Haixia Guan Wei Cui Li Gao Zairong Gao Lin Guo Zhuming Guo Tao Huang Xiaoming Huang Yansong Lin Qinjiang Liu Xin Ni Jianwu Qin Li Ren Zhongyan Shan Hui Sun Xudong Wang Zhengang Xu Yang Yu Bin Zhang DaiweiZhao Ying Zheng Jingqiang Zhu Xiangqian Zheng 无 | 2018 | Cancer Biology & Medicine2018，15，4： | 3 |
| 19 | Outcome of Patients with Colorectal Liver Metastasis: Analysis of 1,613 Consecutive Cases显示文摘 | Zhu Dexiang Ren Li Wei Ye Wu Haifu Zhong Yunshi Ye Qinghai Zhai Shenyong Xu Bo Liang Li Pan Xiangou Li Haohao Ye Lechi Liu Tianshu Fan Jia Qin Xinyu Xu Jianmin | 2012 | Annals of Surgical Oncology2012，，9： | 3 |
| 20 | Liuwei Dihuang formula(六味地黄方)protect endothelial cells from apoptosis by up-regulating expression of estrogen receptor-α显示文摘OBJECTIVE:To evaluate the efficacy of Liuwei Dihuang formula(六味地黄方,LWDHF)on endothelial cells,and to study the mechanism behind the action of modulating expression of estrogen receptors.METHODS:Hydrogen peroxide(H_(2)O_(2))was applied to induce the apoptosis of human umbilical vein endothelial cells(HUVECs).The concentration of nitric oxide(NO),endothelial nitric oxide synthase(eNOS)and inducible NOS(iNOS)were measured by assay kits.Western blot and real-time polymerase chain reaction(RT-PCR)were used to detect the expression of iNOS,eNOS,b-cell lymphoma-2(Bcl-2),Bcl-2-associated X protein(Bax),estrogen receptor(ER)αand ERβ.Also,small interfering RNA(siRNA)was involved to confirm whether the protective effects of LWDHF was medicated by ERs.In vivo,the female rats were ovariectomized to establish postmenopausal vascular injury model.Then the model rats were divided into three groups and treated with saline,estradiol and LWDHF respectively.The concentration of NO and NOS in serum were measured by assay kits,and the expression of Bax,Bcl-2,ERαand ERβwere detected by western blot and immunohistochemistry.RESULTS:In vitro study,LWDHF significantly protected HUVECs from H_(2)O_(2)-induced apoptosis,with the increase of Bcl-2 and the decrease of Bax.The treatment with LWDHF inhibited concentration of NO and iNOS,and upregulated the expression of eNOS,ERαand ERβ.In addition,ERαsiRNA could block the protective effects of LWDHF,while ERβsiRNA showed little influence.In vivo,the treatment with LWDHF suppressed the vascular injury and reduced the level of NO and NOS.LWDHF increased the expression of Bcl-2,ERαand ERβ,as well as inhibiting the Bax expression.CONCLUSION:LWDHF could improve endothelial function and protect HUVECs from apoptosis via increasing the expression of ERα. | CHEN Qi QI Xu FU Yu JI Tingting CHAO Ying LI Jun MENG Qinghai BIAN Huimin LI Yu | 2021 | Journal of Traditional Chinese Medicine2021，41，2： | 3 |
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