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| 1 | Tree ring based streamflow reconstruction for the Upper Yellow River over the past 1234 years显示文摘We established a Juniperus przewalski tree ring width chronology, based on tree ring cores collected from the A’nyêmaqên Mountains. Statistical analysis showed that the chronology was highly correlated with instrumental streamflow records from previous August to current July from the Tangnaihai Station in the upper reaches of the Yellow River, with a correlation coefficient of 0.656. Streamflow for the upper reaches of the Yellow River was reconstructed for the past 1234 years. Low flow periods for the 11-year averaged streamflow reconstruction were definite as lower than mean plus 1 standard deviation, and high flow periods were higher than mean minus 1 standard deviation. Over the past 1234 years, high flows occurred 18 times, and low flows occurred 12 times. The main low flow periods were identified as AD 1140–1156, AD 1295–1309, AD 1473–1500, and AD 1820–1847, and the main high flow periods were identified as AD 846–873, and AD 1375–1400. Extremely low streamflow over the reconstruction period was seen during the late 15th century, coinciding with a widespread drought phenomenon, which took place in the northeastern Tibetan Plateau over the same period. Reconstructed streamflow shows significant low-frequency variability, which is in line with drought variability of neighboring regions, as inferred from tree rings and other proxies. Multi-taper spectral analysis suggests the existence of significant periods of 2–5, 22, 35–38, 55–62, and 114–227 years, particularly significant for cyclic variations of years 159 and 36. | GOU XiaoHua DENG Yang CHEN FaHu YANG MeiXue FANG KeYan GAO LinLin YANG Tao ZHANG Fen | 2010 | Chinese Science Bulletin2010，55，36： | 37 |
| 2 | The Impacts of Permafrost Change on NPP and Implications:A Case of the Source Regions of Yangtze and Yellow Rivers显示文摘This paper studies the relationship between net primary productivity (NPP) and annual average air temperature (GT) at 0cm above ground in permafrost regions by using revised Chikugo NPP model,cubic spline interpolating functions,and non-linear regression methods.The source regions of the Yangtze and Yellow Rivers were selected as the research areas.Results illustrate that:(1) There is significant non-linear relationship between NPP and GT in various typical years;(2) The maximum value of NPP is 6.17,5.87,7.73,and 5.41 DM·t·hm-2 ·a-1 respectively,and the corresponding GT is 7.1,10.0,21.2,and 8.9 o C respectively in 1980,1990,2000 and 2007;(3) In 1980,the sensitivity of NPP to GT is higher than in 1990,2000 and 2007.This tendency shows that the NPP presents change from fluctuation to an adaptation process over time;(4) During 1980~2007,the accumulated NPP was reduced to 8.05,and the corresponding carrying capacity of theoretical livestock reduced by 11%;(5) The shape of the demonstration region of ecological compensation system,livelihood support system,and science appraisal system in the source regions of Yangtze and Yellow Rivers are an important research for increasing the adaptation capacity and balancing protection and development. | FANG Yiping QIN Dahe DING Yongjian YANG Jianping XU Keyan | 2011 | Journal of Mountain Science2011，8，3： | 9 |
| 3 | An experiment-library least-squares method on on-line coal element contents analysis显示文摘A new experiment-library least-squares(experiment-LLs) method used in the neutron inelastic-scattering and thermal-capture analysis(NITA) technique for on-line coal analysis was developed,which has significantly decreased the non-linear radiation effects.In this method,sixty samples with preset elemental contents were made,from whose experimental spectra twenty single-element spectrum libraries corresponding to twenty kinds of coal were built using the least-squares method.The spectrum of the unknown sample was analyzed based on these twenty libraries to estimate its element contents.With the initial estimated result,the procedure of developing library and analysis was iterated to build a new library with the closest element contents to the unknown sample.Hence the experiment-LLs method can reduce non-linear radiation effects.The experiment-LLs method was performed on an improved coal analysis system which was equipped with a long-life 14 MeV pulsed-neutron generator,a bulk BGO detector with a temperature controller,a moisture meter and coal-smoothing device.The precisions of this system for ash content,water content,volatile content and calorific value have reached 1.0wt%,0.5wt%,1.0wt%,350 kJ/kg,respectively. | WANG HuiDong LU JingBin LU YuPing YANG Dong MA KeYan YANG Kang LIU YuMin CHENG DaoWen | 2012 | Science China(Physics,Mechanics & Astronomy)2012，55，11： | 6 |
| 4 | Vegetation and climate change during Marine Isotope Stage 3 in China显示文摘Fossil pollen records from 45 sites across China were evaluated and synthesized to document vegetation and climate change during Marine Isotope Stage 3(MIS 3)at 60–27 ka and to understand the large-scale controls.During MIS3, vegetation type was dominantly forest in eastern China, forest steppe/meadow in the north and Tibetan Plateau, and steppe desert in northwestern arid China. We developed a semi-quantitative vegetation index to reflect change in plant abundance(by inferring the general climate conditions), with a vegetation score from 1to 3 based on the different vegetation types inferred from pollen data at individual sites at intervals of 2,000 years.The reconstructed vegetation index shows higher values during MIS 3, especially during the period 53–40 ka, than at the Last Glacial Maximum. Our results also suggest that climate on the basis of vegetation change was cooler and drier during MIS 3 than during the Holocene optimum;however, MIS 3 vegetation was probably similar to modern vegetation. The close relationship between vegetation change, insolation and Asian summer monsoon strength suggests that climate variations, probably in both temperature and precipitation, are the primary drivers of regional vegetation change. Additional well-dated, high-resolution palaeoclimate records from many locations across China will be needed to understand the vegetation change and climate forcings on millennial and centennial scales within MIS 3. | Yan Zhao Zicheng Yu Ulrike Herzschuh Bao Yang Hui Zhao Keyan Fang Huan Li Quan Li | 2014 | Chinese Science Bulletin2014，59，33： | 2 |
| 5 | 3D Mineral Prospectivity Mapping Based on Deep Metallogenic Prediction Theory:A Case Study of the Lala Copper Mine,Sichuan,China显示文摘With the decrease in surface and shallow ore deposits,mineral exploration has focused on deeply buried ore bodies,and large-scale metallogenic prediction presents new opportunities and challenges.This paper adopts the predictive thinking method in this era of big data combined with specific research on the special exploration and exploitation of deep-earth resources.Four basic theoretical models of large-scale deep mineralization prediction and evaluation are explored:mineral prediction geological model theory,multidisciplinary information correlation theory,mineral regional trend analysis theory,and mineral prediction geological differentiation theory.The main workflow of large-scale deep resource prediction in the digital and information age is summarized,including construction of ore prospecting models of metallogenic systems,multiscale 3 D geological modeling,and 3 D quantitative prediction of deep resources.Taking the Lala copper mine in Sichuan Province as an example,this paper carries out deep 3 D quantitative prediction of mineral resources and makes a positive contribution to the future prediction and evaluation of mineral resources. | Keyan Xiao Jie Xiang Mingjing Fan Yang Xu | 2021 | Journal of Earth Science2021，32，2： | 2 |
| 6 | Reconstructed droughts for the southeastern Tibetan Plateau over the past 568 years and its linkages to the Pacific and Atlantic Ocean climate variability显示文摘 | Keyan Fang Xiaohua Gou Fahu Chen Jinbao Li Rosanne D’Arrigo Edward Cook Tao Yang Nicole Davi | 2010 | Climate Dynamics2010，，4： | 1 |
| 7 | Uncertainty Visualisation of a 3D Geological Geometry Model and Its Application in GIS-Based Mineral Resource Assessment:A Case Study in Huayuan District,Northwestern Hunan Province,China显示文摘This paper reports an application of uncertainty visualisation of a regional scale(1:50000)3 D geological geometry model to be involved in GIS-based 3 D mineral potential assessment of the Xiangxibei lead-zinc mineral concentration area in northwestern Hunan District,China.Three-dimensional(3 D)geological modelling is a process of interpretation that combines a set of input measurements in geometry.Today,technology has become a necessary part of GIS-based deep prospecting.However,issues of sparse data and imperfect understanding exist in the process so that there are several uncertainties in 3 D geological modelling.And these uncertainties are inevitably transmitted into the post-processing applications,such as model-based mineral resource assessment.Thus,in this paper,first,a big-data-based method was used to estimate the uncertainty of a 3 D geological model;second,a group of expectations of geological geometry uncertainty were calculated and integrated into ore-bearing stratoisohypse modelling,which is one of the major favourable parameters of assessment for Lead-Zinc(Pb-Zn)deep prospectivity mapping in northwestern Hunan;and finally,prospecting targets were improved. | Nan Li Cangbai Li Wenkai Chu Keyan Xiao Weihan Tao Xianglong Song Rui Cao Yang Xu Mingjing Fan | 2021 | Journal of Earth Science2021，32，2： | 1 |
| 8 | In-situ encapsulation ofα-Fe_(2)O_(3) nanoparticles into ZnFe_(2)O_(4) micro-sized capsules as high-performance lithium-ion battery anodes显示文摘Transition metal oxides as anode materials for high-performance lithium-ion batteries suffer from severe capacity decay,originating primarily from particle pulverization upon volume expansion/shrinkage and the intrinsically sluggish electron/ion transport.Herein,in-situ encapsulation ofα-Fe_(2)O_(3) nanoparticles into micro-sized ZnFe_(2)O_(4) capsules is facilely fulfilled through a co-precipitation process and followed by heat-treatment at optimal calcination temperature.The porous ZnFe_(2)O_(4) scaffold affords a synergistic confinement effect to suppress the grain growth ofα-Fe2 O3 nanocrystals during the calcination process and to accommodate the stress generated by volume expansion during the charge/discharge process,leading to an enhanced interfacial conductivity and inhibit electrode pulverization and mechanical failure in the active material.With these merits,the preparedα-Fe_(2)O_(3)/Fe_(2)O_(4) composite delivers prolonged cycling stability and improved rate capability with a higher specific capacity than soleα-Fe_(2)O_(3) and Fe_(2)O_(4).The discharge capacity is retained at 700 mAh g-1 after 500 cycles at 200 mA g^(-1) and 940 mAh g^(-1) after 50 cycles at 100 m A g^(-1).This work provides a new perspective in designing transition metal oxides for advanced lithium-ion batteries with superior electrochemical properties. | Wei Wu Yongshan Wei Hongjiang Chen Keyan Wei Zhitong Li Jianhui He Libo Deng Lei Yao Haitao Yang | 2021 | Journal of Materials Science & Technology2021，，16： | 1 |
| 9 | One-Meson Exchange in Quantized Two-Breather Model显示文摘Instead of two-kink system,two-breather system under sum ansatz is quantized.A covariant meson-breather interaction to the one-meson range and to the leading nonstatic order is obtained.All of the results depend on breather internal variable θ. | YANG Keyan | 1991 | Chinese Physics Letters1991，8，3： | 0 |
| 10 | Miro2 supplies a platform for Parkin translocation to damaged mitochondria显示文摘PINK1/Parkin-mediated mitophagy is an important process in selective removal of damaged mitochondria, in which translocation of Parkin to damaged mitochondria is recognized as an initiation step. At present, how the damaged mitochondria are selectively recognized and targeted by Parkin is not fully understood. Here we show that Miro2, an outer mitochondrial membrane protein, undergoes demultimerization from a tetramer to a monomer and alteration in mitochondrial localization upon CCCP treatment, suggesting a CCCP-induced realignment of Miro2. The realignment of Miro2 is tightly regulated by PINK1-mediated phosphorylation at Ser325/Ser430 and by Ca^2+binding to EF2 domain, which are both essential for the subsequent Parkin translocation. Interestingly, ablation of Miro2 in mouse causes delayed reticulocyte maturation, lactic acidosis and cardiac disorders. Furthermore, several Miro2 mutations found in the congenital lactic acidosis patients also disable its realignment and Parkin translocation. These findings reveal an important role of Miro2 to mediate Parkin translocation by sensing both depolarization and Ca^2+release from damaged mitochondria to ensure the accuracy of mitophagy. | Jiu-Qiang Wang Shu Zhu Yihan Wang Fengli Wang Chaoqiang An Dongfang Jiang Lijie Gao Yingfeng Tu Xuefei Zhu Yun Wang Hongmei Liu Juanjuan Gong Zhongshuai Sun Xi Wang Leimei Liu Keyan Yang Caixia Guo Tie-Shan Tang | 2019 | Science Bulletin2019，64，11： | 0 |
| 11 | Effects of calcium carbonate on preparation and mechanical properties of wood/plastic composite显示文摘In order to reduce the cost and improve the performance of wood/plastic composite(WPC),the effects of additive amount of calcium carbonate on preparation and mechanical properties of high density polyethylene(HDPE)based WPC were studied.The results showed that the calcium carbonate can improve preparation and mechanical properties effectively.The 20%calcium carbonate additive could effectively improve the melt fluidity of the composites and reduce the energy consumption in the processing.The calcium carbonate had a favorable toughening effect on polymer and was effectively filled in WPC.For the best tensile,flexural and impact properties of WPC,the appropriate additive amounts of calcium carbonate were 25%,10%and 30%,respectively.The additive amount for preparation of WPC should be based on the processing requirements and the demands for different working conditions. | Cai Hongzhen Yang Keyan Yi Weiming | 2017 | International Journal of Agricultural and Biological Engineering2017，10，1： | 0 |
| 12 | miRNA-141-5p Affects the Levels of Neutrophil Elastase in Preeclampsia by Regulating MAPK1显示文摘Objective:The objective of this study was to investigate the expression levels of microRNA-141-5p(miRNA-141-5p),MAPK1 and neutrophil elastase in patients with and without preeclampsia(PE),and the relationship between miRNA-141-5p and MAPK1 with respect to the secretion of elastase by neutrophils in patients with PE.Methods:Thirty patients with PE and 30 healthy pregnant(HP)women were recruited from The Second Hospital of Shanxi Medical University,Taiyuan,China,between February 2017 and July 2018.Neutrophils were isolated from 8 mL peripheral blood samples and cultured.We recorded neutrophil count and morphology during culture.Apoptosis was detected by flow cytometry in different groups at 0,24,and 48 h.The expression levels of elastase were detected in neutrophils by enzyme-linked immunosorbent assay,whereas the expression levels of miRNA-141-5p in peripheral blood neutrophils were detected by real-time polymerase chain reaction.We used TargetScanHuman Release 7.2 to analyze the target genes of miRNA-141-5p.The expression of MAPK1 in peripheral blood neutrophils was detected by western blotting.Data were analyzed by SPSS version 21.0 software,and comparisons between groups were carried out with the Studentt test.Results:There was no significant difference between the PE and HP groups(P>0.050)with regard to age or body mass index.The weight of newborns in the PE group(2846.00±600.00 g)was significantly lower than that in the HP group(3055.00±230.68 g).The number of neutrophilic granulocytes(NGs)in blood samples from the PE group was significantly higher than that in the HP group(P=0.003).There was no significant difference between the groups with regard to morphology.Apoptosis in the PE group was delayed when compared with the HP group at different time points.TheP value of apoptosis in the PE and HP groups were respectively 0.790,<0.001 and 0.030 at 0 h,24 h and 48 h.The expression levels of miRNA-141-5p in the PE group were significantly lower than those in the HP group(P<0.050).The expression levels of MAPK1 in neutrophils from the PE group were significantly higher than those in the HP group(P<0.050)by western blot.The expression levels of elastase in neutrophils from the PE group were significantly higher than those in the HP group(P<0.050).Furthermore,the number of NGs in peripheral blood from the PE group was higher than that of the HP group;however,the levels of apoptosis were lower.The expression levels of miRNA-141-5p in NGs decreased,the expression of MAPK1 increased,and the secretion of neutrophil elastase in the NG medium increased in the PE group than those in the HP group.Conclusion:Collectively,our analysis suggested that miRNA-141-5p may be involved in the pathogenesis of PE by regulating the MAPK1 signaling pathway to activate neutrophils and increase the secretion of elastase. | Keyan Cheng Jialei Cui Wenli Zhou Huiqiang Liu Taotao Yang Yonghong Wang | 2022 | Maternal-Fetal Medicine2022，4，4： | 0 |
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