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1A complete sequence and comparative analysis of a SARS-associated virus(Isolate BJ01)显示文摘The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of transmission and pathogenesis, development of diagnostics, prevention by future vaccination, and treatment by developing new drugs. We report the complete genome sequence and comparative analysis of an isolate (BJ01) of the coronavirus that has been recognized as a pathogen for SARS. The genome is 29725 nt in size and has 11 ORFs (Open Reading Frames). It is composed of a stable region encoding an RNA-dependent RNA polymerase (composed of 2 ORFs) and a variable region representing 4 CDSs (coding sequences) for viral structural genes (the S, E, M, N proteins) and 5 PUPs (putative uncharacterized proteins). Its gene order is identical to that of other known coronaviruses. The sequence alignment with all known RNA viruses places this virus as a member in the family of Coronaviridae. Thirty putative substitutions have been identified by comparative analysis of the 5 SARS- associated virus genome sequences in GenBank. Fifteen of them lead to possible amino acid changes (non-synonymous mutations) in the proteins. Three amino acid changes, with predicted alteration of physical and chemical features, have been detected in the S protein that is postulated to beinvolved in the immunoreactions between the virus and its host. Two amino acid changes have been detected in the Mprotein, which could be related to viral envelope formation. Phylogenetic analysis suggests the possibility of non-human origin of the SARS-associated viruses but provides noevidence that they are man-made. Further efforts should focus on identifying the etiology of the SARS-associated virus and ruling out conclusively the existence of otherpossible SARS-related pathogen(s).QIN E'de ZHU Qingyu YU Man FAN Baochang CHANG Guohui SI Bingyin YANG Bao PENG Wenming JIANG Tao LIU Bohua DENG Yongqiang LIU Hong ZHANG Yu WANG Cui LI Yuquan GAN Yonghua LI Xiaoyu L Fushuang TAN Gang CAO Wuchun, YANG Ruifu Institute of Microbiology and Epidemiology, Chinese Academy of Military Medical Sciences, Beijing 100071, China WANG Jian, LI Wei, XU Zuyuan, LI Yan, WU Qingfa, LIN Wei, CHEN Weijun, TANG Lin, DENG Yajun, HAN Yujun, LI Changfeng, LEI Meng, LI Guoqing, LI Wenjie, L Hong, SHI Jianping, TONG Zongzhong, ZHANG Feng, LI Songgang, LIU Bin, LIU Siqi, DONG Wei, WANG Jun, Gane K-S Wong, YU Jun & YANG Huanming* Beijing Genomics Institute, Chinese Academy of Sciences, Beijing 101300 National Center for Genome Information, Beijing 101300, China 2003Chinese Science Bulletin2003,48,10:121
2Non-canonical regulation of SPL transcription factors by a human OTUBl-like deubiquitinase defines a new plant type rice associated with higher grain yield显示文摘完成增加的谷物生产率长是引起节目的谷物的制服的焦点。ideotype 途径被用来在国际瑞斯研究院并且在中国改进米饭收益潜力。然而,在米饭的收益相关的特点的基因基础仍然保持不清楚。这里,我们显示出那一个主要量的特点地点, qNPT1,通过建筑学由更少 tillers 描绘了的一种新植物类型(NPT ) 的决心的行为,更坚定的灰煤杆和更大的圆锥花序,并且它与相同编码 deubiquitinating 酶到人的 OTUB1。OsOTUB1 的 Downregulation 提高 meristematic 活动,导致在谷物产量的减少的 tiller 数字,增加的谷物数字,提高的谷物重量和米饭的作为结果的增加。不同于人的 OTUB1, OsOTUB1 能劈开连接 K48 、连接 K63 的 polyubiquitin。OsOTUB1 与 E2 结合 ubiquitin 蛋白质 OsUBC13 和 squamosa 倡导者绑定交往像蛋白质的抄写因素 OsSPL14。OsOTUB1 和 OsSPL14 分享普通目标基因,和他们的物理相互作用限制 OsSPL14 的连接 K63 的 ubiquitination (K63Ub ) ,它接着支持 OsSPL14 的 K48Ub 依赖的 proteasomal 降级。相反地, OsOTUB1 的 loss-of-function 与 OsSPL14 的高水平的累积被相关,导致 NPT 建筑学。我们也证明 high-yielding npt1 和 dep1-1 等位基因节节上升为增加在当前是可完成的的上面的米饭收益潜力提供新策略。Shuansuo Wang Kun Wu Qian Qian Qian Liu Qi Li Yajun Pan Yafeng Ye Xueying Liu Jing Wang Jianqing Zhang Shan Li Yuejin Wu Xiangdong Fu 2017Cell Research2017,27,9:33
3Controlling N-doping type in carbon to boost single-atom site Cu catalyzed transfer hydrogenation of quinoline显示文摘Single-atom site(SA)catalysts on N-doped carbon(CN)materials exhibit prominent performance for their active sites being M-Nx.Due to the commonly random doping behaviors of N species in these CN,it is a tough issue to finely regulate their doping types and clarify their effect on the catalytic property of such catalysts.Herein,we report that the N-doping type in CN can be dominated as pyrrolic-N and pyridinic-N respectively through compounding with different metal oxides.It is found that the proportion of distinct doped N species in CN depends on the acidity and basicity of compounded metal oxide host.Owing to the coordination by pyrrolic-N,the SA Cu catalyst displays an enhanced activity(two-fold)for transfer hydrogenation of quinoline to access the valuable molecule tetrahydroquinoline with a good selectivity(99%)under mild conditions.The higher electron density of SA Cu species induced by the predominate pyrrolic-N coordination benefits the hydrogen transfer process and reduces the energy barrier of the hydrogenation pathway,which accounts for the improved catalytic effeciency.Jian Zhang Caiyan Zheng Maolin Zhang Yajun Qiu Qi Xu Weng-Chon Cheong Wenxing Chen Lirong Zheng Lin Gu Zhengpeng Hu Dingsheng Wang Yadong Li 2020Nano Research2020,13,11:29
4PTEN-L is a novel protein phosphatase for ubiquitin dephosphorylation to inhibit PINK1-Parkin-mediated mitophagy显示文摘Mitophagy 是为损坏线粒体的特定的消除的选择 autophagy 的一种重要类型。(PINK1 )导致 PTEN 的通常认为的 kinase 蛋白质 1 催化 ubiquitin (Ub ) 的 phosphorylation 在 PINK1-Parkin-mediated mitophagy 的发作起一个关键作用。(PTEN-L ) 磷酸酶和 tensin 相当或相同的事物(PTEN ) 长是 PTEN 的最新识别的 isoform,与到它的 N 终点的 173 氨基酸的增加。这里,我们报导 PTEN-L 是经由它对 phosphorylated ubiquitin 的蛋白质磷酸酶活动的 mitophagy 的一个新奇否定管理者。我们发现 PTEN-L 在外部 mitochondrial 膜(OMM ) 本地化,而 PTEN-L 的删除支持, PTEN-L 的 overexpression 禁止, mitophagy 由各种各样的损坏线粒体的代理人导致了。机械学地, PTEN-L 能够有效地阻止 Parkin mitochondrial translocation,减少 Parkin phosphorylation,维持它的关上的不活跃的符合构造,并且禁止它的 E3 ligase 活动。更重要地, PTEN-L 在 vivo 减少 phosphorylated ubiquitin (pSer65-Ub ) 的水平,并且在 vitro,磷酸酶试金经由它的蛋白质磷酸酶活动证实那 PTEN-L dephosphorylates pSer65-Ub,独立于它的类脂化合物磷酸酶功能。一起拿,我们的调查结果为 ubiquitin 作为蛋白质磷酸酶表明 PTEN-L 的新奇功能,它抵抗在 mitophagy 正式就职和 mitophagy 的最终的抑制导致前馈控制机制的阻塞的调停 PINK1 的 ubiquitin phosphorylation。因此,理解 PTEN-L 的这新奇功能在控制 mitophagy 的分子的难题提供一关键错过片,在包括象 Parkinsons 那样的 neurodegenerative 混乱的许多重要人的疾病的一个批评过程疾病。Liming Wang Yik-Lam Cho Yancheng Tang Jigang Wang Jung-Eun Park Yajun Wu Chunxin Wang Yan Tong Ritu Chawla Jianbin Zhang Yin Shi Shuo Deng Guang Lu Yihua Wu Hayden Weng-Siong Tan Pornteera Pawijit Grace Gui-Yin Lim Hui-Ying Chan Jingzi Zhang Lei Fang Hanry Yu Yih-Cherng Liou Mallilankaraman Karthik Boon-Huat Bay Kah-Leong Lim Siu-Kwan Sze Celestial T. Yap Han-Ming Shen 2018Cell Research2018,28,8:25
5Xinfeng capsule improves pulmonary function in ankylosing spondylitis patients via NF-κB-iNOS-NO signaling pathway显示文摘OBJECTIVE: To study changes in the nuclear factor-κB p65(NF-κB p65)-inducible nitric oxide synthase(i NOS)-nitric oxide(NO) signaling pathway and the effects of Xinfeng capsules(XFC) in patients with ankylosing spondylitis(AS)METHODS: One hundred twenty patients with AS were randomly divided into an XFC group and a Salazopyrin group. Sixty health subjects were included as a normal control group. In the two treatment groups, pulmonary functional parameters,forced vital capacity(FVC), forced expiratory volume in 1 second(FEV1), maximal voluntary ventilation(MVV), peak expiratory flow(PEF), forced expiratory flow at 25% of forced vital capacity(FEF25),forced expiratory flow at 50% of forced vital capacity(FEF50), and forced expiratory flow at 75% of forced vital capacity(FEF75) were determined. Enzyme linked immunosorbent assays were used for detection of the serum oxidative stress indexes,NF-κB p65, i NOS, NO, reactive oxygen species(ROS), reactive nitrogen species(RNS), malondialdehyde(MDA), superoxide dismutase(SOD), catalase(CAT), total antioxidative capacity(TAOC) and interleukin-4(IL-4), IL-10, IL-1β, and tumor necrosis factor-α(TNF-α) contents. Westergren's method was used for determination of erythrocyte sedimentation rate(ESR). High-sensitivity C-reactive protein(Hs-CRP) was detected with a 7060 full-automatic biochemical analyzer(Hitachi, Japan).RESULTS: The clinical therapeutic effect in the XFC group was significantly superior to that in the Salazopyrin group(P<0.01). Compared with the normal control group, FEV1, MVV, PEF, FEF50, FEF75, SOD, CAT,TAOC, IL-4, IL-10 were significantly lower, and NF-κB p65, i NOS, NO, ROS, RNS, MDA, IL-1β, TNF-α, ESR,and Hs-CRP significantly higher in patients with AS(P<0.01 or P<0.05). Compared with before treatment, FEV1, MVV, PEF, FEF50, FEF75, SOD, CAT, TAOC,IL-4, and IL-10 were significantly increased, and NF-κB p65, i NOS, NO, ROS, RNS, MDA, IL-1β, TNF-α,ESR, CRP, visual analog scales(VAS), Bath ankylosing spondylitis disease active index, Bath ankylosing spondylitis functional index, and Bath ankylosing spondylitis global index significantly decreased in the two treatment groups after treatment(P<0.01 or P<0.05), with significant differences between the XFC and Salazopyrin groups(P<0.01 or P<0.05). Spearman correlation analysis indicated that FEV1, MVV, PEF, FEF50, and FEF75 were positively correlated with SOD, CAT, TAOC, IL-4, and IL-10, and were negatively correlated with NF-κB p65, i NOS,NO, ROS, RNS, MDA, IL-1β, TNF-α, ESR, and CRP.CONCLUSION: Patients with AS have local pathologic changes in the spinal cord and other joints.They also have decreased pulmonary function,which is negatively correlated with the NF-κB-i NOS-NO signaling pathway, oxidative indexes, and inflammatory factors. XFC improves rigidity and pain in spinal joints and other symptoms, laboratory indexes, and pulmonary function. The mechanism is possibly related to inhibition of the NF-κB-i NOS-NO signaling pathway.Jian Liu Yajun Qi Li Zheng Yunxiang Cao Lei Wan Wenfang Ye Li Fang 2014Journal of Traditional Chinese Medicine2014,34,6:24
6Permeability analysis of fractured vuggy porous media based on homogenization theory显示文摘Based on the characteristics of fractured vuggy porous media,a novel mathematical model was proposed to model fluid flow in such media on fine scale,i.e.,the discrete fracture-vug network model.The new model consists of three systems:porous rock system,fracture system,and vug system.The fractures and vugs are embedded in porous rock,and the isolated vugs could be connected via the discrete fracture network.The flow in porous rock and fractures follows Darcy's law,and the vugs system is free fluid region.Using a two-scale homogenization limit theory,we obtained a macroscopic Darcy's law governing the media on coarse scale.The theoretical formula of the equivalent permeability of the fractured vuggy porous media was derived.The model and method of this paper were verified by some numerical examples.At the end the permeability of some fractured vuggy porous media with typical fracture-vug structures was analyzed.HUANG ZhaoQin,YAO Jun,LI YaJun,WANG ChenChen&LüXinRui College of Petroleum Engineering,China University of Petroleum,Qingdao 266555,China 2010Science China(Technological Sciences)2010,53,3:22
7Chinese Overseas investment Calls for Perfection of Overseas Investment Insurance显示文摘Overseas investment insurance is a non-profitable insur- ance provided by the government of a state for her enterprises which have invested in the developing countries or areas against political risks.Such a gov- ernmental guarantee system was first established in the United States in the middle of last century.Nowadays most developed countries and some of the developing countries have followed American practices and set up similar systems to encourage their enterprises to make investment in developing areas which are often regarded to be more easily to have political risks.InLiu Yajun,associateprofessor,tutor of postgraduate,vice dean of the School of International Law of Northwest University of Political Science and Law.His main research orientation includes international trade law and international investment law. 2008China's Foreign Trade2008,,8:22
8A DTX/MATE-Type Transporter Facilitates Abscisic Acid Efflux and Modulates ABA Sensitivity and Drought Tolerance in Arabidopsis显示文摘Abscisic 酸(骆驼毛的织物) 在植物调整众多的生理、发展的过程。最近的研究识别 intracellularABA 受体,含有越过为骆驼毛的织物察觉到和反应同样关键的房间膜的骆驼毛的织物的运输。这里,我们 reportthat DTX/Multidrug 和有毒的复合挤出(配偶) 在 Arabidopsis thaliana 的家庭成员, AtDTX50,作为骆驼毛的织物流出 transporter 工作。当在 Escherichia coli 紧张和 Xenopus 卵母细胞房间 heterologously 表示了时, AtDTX50 被发现便于骆驼毛的织物流出。而且,与骆驼毛的织物预装的 dtx50 异种叶肉房间释放了更少的骆驼毛的织物与相比野类型(WT ) 。AtDTX50 基因主要在脉管的纸巾和警卫房间被表示,它的表示由 exogenousABA 是强烈起来调整的。AtDTX50::GFP 熔化蛋白质对血浆膜主要局部性。dtx50 异种植物被观察对在生长抑制的骆驼毛的织物更敏感。另外与 WT 相比, dtx50 异种植物对有更低的有气孔的传导力的干旱更容忍,与它是的功能一致在警卫房间的骆驼毛的织物 effluxcarrier。Haiwen Zhang Huifen Zhu Yajun Pan Yuexuan Yu Sheng Luan Legong Li 2014Molecular Plant2014,7,10:23
9Extraction of scandium from red mud by modified activated carbon and kinetics study显示文摘激活的碳(交流) 被 tri 丁基磷酸盐(TBP ) 为有选择地从红泥提取钪修改并且由赌注(Brunauer-Emmett-Teller ) 表面区域描绘了。修改交流有优先的吸附到钪。到钪的吸附能力和选择上的吸附物剂量,吸附温度,和时间的影响被检验。最佳吸附物剂量(6.25 g/L ) ,吸附温度(308 K ) ,和吸附时间(40 min ) 被弄明白。一个 pseudo-second-order 动力学模特儿为描述钪的吸附过程被雇用。ZHOU Hualei LI Dongyan TIAN Yajun CHEN Yunfa 2008Rare Metals2008,27,3:20
10Medusoid Fossils from the Sinian Xingmincun Formation of Southern Liaoning Province显示文摘Abundant medusoid soft-bodied metazoan fossils have been found in the Sinian Xingmincun Formation(with an isotopic age of 650 Ma) at Qipanmo, Qidingshan and Yangtun of the Dalian-Jinzhou area, southern Liaoning Province; in addition, a number of macroscopic algal fossils have been discovered for the first time in the Getun Formation overlying the Xingmincun Formation. Medusoid fossils include 3 genera and 6 species(all of which are new). Judging from their biological characters, these medusoid fossils are considered to have an intimate affinity with the Ediacara fauna in the terminal Precambrian of Australia, as their characters are close to each other. The authors suggest that these medusoids and the Edicara fauna might be the products of the same period. The discovery of the medusoid fauna in the Xingmincun Formation marks an important event in the evolution of the terminal Precambrian organisms in China, and it is of major practical significance in the study of the Sinian System of China and the correlation of the Sinian strata of northern and southern China.Hong Zuomin, Huang Zhenfu, Yang Xinde, Lan Jing, Xian Bingcai, Yang Yajun, Regional Geological Survey Party, Bureau of Geology and Mineral Resources of Liaoning Province, Jinzhou, Liaoning and Liu Xiaoliang Shenyang Institute of Geology and Resources, Chinese Academy of Geological Sciences, Shenyang, Liaoning Fang Xinzhong 1989Acta Geologica Sinica(English Edition)1989,63,1:20
11Zircon U-Pb geochronology of the volcanic rocks from Fanchang-Ningwu volcanic basins in the Lower Yangtze region and its geological implications显示文摘The latest eruptions in two important Mesozoic volcanic basins of Fanchang and Ningwu located in the middle-lower reaches of the Yangtze River formed the bimodal volcanic rocks of the Kedoushan Formation and ultrapotassic volcanic rocks of the Niangniangshan Formation, respectively. The repre-sentative volcanic rocks of the two Formations were selected for LA-ICPMS zircon U-Pb dating. The results indicate that there exist a large amount of magmatic zircons as indicated by high Th/U ratios in these volcanic rocks. The weighted mean age of 21 analyses is 130.7±1.1 Ma for the Kedoushan Formation, and that of 20 analyses is 130.6±1.1 Ma for the Niangniangshan Formation. These U-Pb ages are interpreted to represent the formation times of the volcanic rocks. In combination with other known geochronological data for Mesozoic volcanic rocks from the Lower Yangtze region, it is proposed that the latest volcanic activations in the Jinniu, Luzong, Fanchang and Ningwu volcanic basins probably came to end prior to ca. 128 Ma. There is no significant time interval between the early and later volcanic activities in the Luzong and Ningwu basins, suggesting a short duration of volcanic activities and thus implying the onset of an extensional tectonic setting at about 130 Ma in the Lower Yangtze region. Integrated studies reveal that the Early Cretaceous magmatic activities and their geochronological framework in the Lower Yangtze region are a response to progressively dynamic deep processes that started with the transformation of tectonic setting from compression to extension, followed by delaminating of the lower part of the thickened lithosphere, lithospheric thinning, asthenosphere upwelling, and crust-mantle interaction.YAN Jun LIU HaiQuan SONG ChuanZhong XU XiSheng AN YaJun LIU Jia DAI LiQun 2009Chinese Science Bulletin2009,54,16:20
12Clinical features and treatment status of hemifacial spasm in China显示文摘Wang Lin Hu Xingyue Dong Hongjuan Wang Wenzhao Huang Yue Jin Lingjing Luo Yumin Zhang Weixi Lian Yajun Liang Zhanhua Shang Huifang Feng Yabo wu Yiwen Chen Jun Luo Weifeng Wan Xinhua 2014Chinese Medical Journal2014,,5:20
13First identification of kdr allele F1534S in VGSC gene and its association with resistance to pyrethroid insecticides in Aedes albopictus populations from Haikou City,Hainan Island,China显示文摘Background:Aedes albopictus is distributed widely in China,as a primary vector of Dengue fever and Chikungunya fever in south of China.Chemical insecticide control is one of the integrated programmes to prevent mosquito-borne diseases.Long-term applications of pyrethroids have resulted in the development of resistance in Ae.albopictus populations in China.However,the susceptibility of Ae.albopictus to pyrethroids in Hainan Island was unclear.Knockdown resistance(kdr),caused by point mutations in the VGSC gene,is one of the mechanisms that confer resistance to DDT and pyrethroids.This study was to investigate the resistance level of Ae.albopictus populations in Haikou City to three pyrethroid insecticides,and elucidate the relationship between the resistant phenotype and kdr mutations.Methods:The Aedes albopictus samples were collected in Xinbu Island(XI),Longtang Town(LT),Shishan Town(ST),Baishamen Park(BP),and Flower Market(FM)from Haikou City,Hainan Island,China.The larval susceptibility to deltamethrin,permethrin and beta-cypermethrin was tested by larval bioassays,and adult susceptibility to deltamethrin and DDT was determined by adult bioassays.The degree of resistance was determined by resistance ratio value(RR50>3)for larvae and by mortality for adult.The kdr alleles at codon 1534 of the VGSC gene were genotyped.The relationship between kdr genotypes and resistant phenotypes was analyzed by Chi-square test.Results:Out of five populations,assessed by larval bioassays,XI was susceptible to deltamethrin and permethrin;LT was susceptible to permethrin and beta-cypermethrin;and ST was susceptible to permithrin.FM and BP both were resistant to all of the three pyrethroids,and FM showed the highest degree of resistance,with RR50 values from 65.17 to 436.36.A total of 493 individuals from the larval bioassays were genotyped for kdr alleles.Five alleles were detected,including two wildtype alleles,TTC(F)(67.04%)and TTT(F)(0.41%),and three mutant alleles,TGC(C)(0.30%),TCC(S)(31.54%)and TTG(L)(0.71%).There was a clear correlation between mutant alleles(or F1534S)and resistant phenotypes(P<0.01).Conclusion:Two novel kdr mutant alleles F1534S and F1534L were detected in the pyrethroid resistant populations of Ae.albopictus in Haikou Hainan,China.For the first time,the mutant F1534S was associated with pyrethroid resistance in Ae.albopictus.Huiying Chen Kaili Li Xiaohua Wang Xinyan Yang Yi Lin Fang Cai Wenbin Zhong Chunyan Lin Zhongling Lin Yajun Ma 2016Infectious Diseases of Poverty2016,5,1:19
14Computed tomography-based radiomics for prediction of neoadjuvant chemotherapy outcomes in locally advanced gastric cancer: A pilot study显示文摘Objective: The standard treatment for patients with locally advanced gastric cancer has relied on perioperative radio-chemotherapy or chemotherapy and surgery. The aim of this study was to investigate the wealth of radiomics for pre-treatment computed tomography(CT) in the prediction of the pathological response of locally advanced gastric cancer with preoperative chemotherapy.Methods: Thirty consecutive patients with CT-staged II/III gastric cancer receiving neoadjuvant chemotherapy were enrolled in this study between December 2014 and March 2017. All patients underwent upper abdominal CT during the unenhanced, late arterial phase(AP) and portal venous phase(PP) before the administration of neoadjuvant chemotherapy. In total, 19,985 radiomics features were extracted in the AP and PP for each patient.Four methods were adopted during feature selection and eight methods were used in the process of building the classifier model. Thirty-two combinations of feature selection and classification methods were examined. Receiver operating characteristic(ROC) curves were used to evaluate the capability of each combination of feature selection and classification method to predict a non-good response(non-GR) based on tumor regression grade(TRG).Results: The mean area under the curve(AUC) ranged from 0.194 to 0.621 in the AP, and from 0.455 to 0.722 in the PP, according to different combinations of feature selection and the classification methods. There was only one cross-combination machine-learning method indicating a relatively higher AUC(>0.600) in the AP, while 12 cross-combination machine-learning methods presented relatively higher AUCs(all >0.600) in the PP. The feature selection method adopted by a filter based on linear discriminant analysis + classifier of random forest achieved a significantly prognostic performance in the PP(AUC, 0.722±0.108; accuracy, 0.793; sensitivity, 0.636; specificity,0.889; Z=2.039; P=0.041).Conclusions: It is possible to predict non-GR after neoadjuvant chemotherapy in locally advanced gastric cancers based on the radiomics of CT.Zhenhui Li Dafu Zhang Youguo Dai Jian Dong Lin Wu Yajun Li Zixuan Cheng Yingying Ding Zaiyi Liu 2018Chinese Journal of Cancer Research2018,30,4:18
15Groundwater hydrochemistry and isotope geochemistry in the Turpan Basin, northwestern China显示文摘The Turpan Basin is located in the arid zone of northwestern China and is a typical closed inland basin surrounded by high mountains. It is one of the most arid regions in the world and, as a result, the groundwater in this area is very important for both domestic and agricultural uses. In the present study, the relationships of major elements(K+, Na+, Ca2+, Mg2+, HCO3-, SO42- and Cl-) and environmental isotopes(δ18O, δ2H and T) in groundwater were analyzed to investigate the evolution of the regional hydrochemistry within the Turpan Basin. The hydrochemistry results demonstrate that groundwater with high total dissolved solids(TDS) concentration is dominated by sodium chloride(Na-Cl) and sodium sulfate(Na-SO4) type water, whereas that with low TDS concentration(typically from near mountain areas) is dominated by calcium bicarbonate(Ca-HCO3) type water. The evolution of groundwater hydrochemistry within the Turpan Basin is a result of calcium carbonate precipitation, evaporation concentration, cation exchange and dissolution of evaporites(i.e. halite, mirabilite and gypsum). Furthermore, evaporite dissolution associated with irrigation practice plays a key role in the groundwater salinization, especially in the central part of the basin. Environmental isotopes reveal that the groundwater is recharged by precipitation in the mountain areas and fast vertical infiltration of irrigation return flow. In the southern sub-basin the shallow groundwater and the deep groundwater is separated at a depth of about 40 m, with substantial differences in terms of hydrochemical and isotopic characteristics. The results are useful for decision making related to sustainable water resource utilization in the Turpan Basin and other regions in northwestern China.Lu CHEN GuangCai WANG FuSheng HU YaJun WANG Liang LIU 2014Journal of Arid Land2014,6,4:13
16Soft-sediment Deformation Structures Related to Earthquake from the Devonian of the Eastern North Qilian Mts.and Its Tectonic Significance显示文摘摘要:在北方 Qilian orogenic 带和 Hexi 走廊的泥盆纪开发了在北方中国板和 Qaidam microplate 之间的碰撞引起的低岬盆的以后的舞台的陆上的 molasse。低岬盆触发了强烈地震,并且形成了 seismites 和地震相关的软沉积的变丑。在东方北方 Qilian 山的泥盆纪的软沉积的变丑结构由 seismo 裂缝组成,沙岩女同性恋, syn-depositional 差错, microfolds (微弄皱迭合) ,使流体化的静脉,负担演员组,火焰结构,枕头结构和 brecciation。seismo 裂缝, syn-depositional 差错和 microfolds 是地震的摆动直接形成的裂缝,差错和褶层。地震女同性恋由沉积灌输进地震裂缝形成了。使流体化的静脉被灌输进使流体化的沙的 seismo 裂缝做。负担演员组,火焰结构和枕头结构被下沉并且灌输形成沿着在沙、泥泞的床之间的脸从地震的摆动引起了。brecciation 源于地震的摆动并且沉积的层裂开。在泥盆纪的 seismites 和软沉积的变丑在造山运动期间触发了与构造活动有关的地震并且北方 Qilian 山高举。DU Yuansheng XU Yajun YANG Jianghai 2008Acta Geologica Sinica(English Edition)2008,82,6:13
17The impact of land use change on soil organic carbon and labile organic carbon stocks in the Longzhong region of Loess Plateau显示文摘Land use change (LUC) is widely recognized as one of the most important driving forces of global carbon cycles. The soil organic carbon (SOC) and labile organic carbon (LOC) stores were investigated at arable land (AL), artificial grassland (AG), artificial woodland (AW), abandoned arable land (AAL) and desert steppe (DS) in the Longzhong region of the Loess Plateau in Northwest China. The results showed that conversions from DS to AL, AL to AG and AL to AAL led to an increase in SOC content, while the conversion from DS to AW led to a decline. The differences in SOC content were significant between DS and AW at the 20-40 cm depth and between AL and AG at the 0-10 cm depth. The SOC stock in DS at the 0-100 cm depth was 39.4 t/hm 2 , increased by 28.48% after cultivation and decreased by 19.12% after conversion to AW. The SOC stocks increased by 2.11% from AL to AG and 5.10% from AL to AAL. The LOC stocks changed by a larger magnitude than the SOC stocks, which suggests that it is a more sensitive index of carbon dynamics under a short-term LUC. The LOC stocks increased at 0-20 cm and 0-100 cm depths from DS to AW, which is opposite to that observed for SOC. The proportion of LOC to SOC ranged from 0.14 to 0.20 at the 0-20 cm depth for all the five land use types, indicating low SOC dynamics. The allocation proportion of LOC increased for four types of LUC conversion, and the change in magnitude was largest for DS to AW (40.91%). The afforestation, abandonment and forage planting on arable land led to sequestration of SOC; the carbon was lost initially after afforestation. However, the carbon sink effect after abandonment may not be sustainable in the study area.LiHua ZHANG ZhongKui XIE RuiFeng ZHAO YaJun WANG 2012Journal of Arid Land2012,4,3:13
18Potential key technologies for 6G mobile communications显示文摘The standard development of 5G wireless communication culminated between 2017 and 2019,followed by the worldwide deployment of 5G networks,which is expected to result in very high data rate for enhanced mobile broadband,support ultrareliable and low-latency services and accommodate massive number of connections.Research attention is shifting to future generation of wireless communications,for instance,beyond 5G or 6G.Unlike previous studies,which discussed the use cases,deployment scenarios,or new network architectures of 6G in depth,this paper focuses on a few potential technologies for 6G wireless communications,all of which represent certain fundamental breakthrough at the physical layer—technical hardcore of any new generation of wireless communications.Some of them,such as holographic radio,terahertz communication,large intelligent surface,and orbital angular momentum,are of revolutionary nature and many related studies are still at their scientific exploration stage.Several technical areas,such as advanced channel coding/modulation,visible light communication,and advanced duplex,while having been studied,may find more opportunities in 6 G.Yifei YUAN Yajun ZHAO Baiqing ZONG Sergio PAROLARI 2020Science China(Information Sciences)2020,63,8:13
19Platelet-rich fibrin-induced bone marrow mesenchymal stem cell differentiation into osteoblast-like cells and neural cells显示文摘Bone marrow mesenchymal stem cells were allowed to develop for 14 days in a platelet-rich fibrin environment.Results demonstrated that platelet-rich fibrin significantly promoted bone marrow mesenchymal stem cell proliferation.In addition,there was a dose-dependent increase in Runt-related transcription factor-2 and bone morphogenetic protein-2 mRNA expression,as well as neuron-specific enolase and glial acidic protein.Results showed that platelet-rich fibrin promoted bone marrow mesenchymal stem cell proliferation and differentiation of osteoblast-like cells and neural cells in a dose-dependent manner.Qi Li Yajun Geng Lei Lu Tingting Yang Mingrui Zhang Yanmin Zhou 2011Neural Regeneration Research2011,6,31:12
20Relative position determination of a lunar rover using the biased differential phase delay of same-beam VLBI显示文摘When only data transmission signals with a bandwidth of 1 MHz exist in the rover, the position can be obtained using the differential group delay data of the same-beam very long baseline interferometry (VLBI). The relative position between a lunar rover and a lander can be determined with an error of several hundreds of meters. When the guidance information of the rover is used to determine relative position, the rover's wheel skid behavior and integral movement may influence the accuracy of the determined position. This paper proposes a new method for accurately determining relative position. The differential group delay and biased differential phase delay are obtained from the same-beam VLBI observation, while the modified biased differential phase delay is obtained using the statistic mean value of the differential group delay and the biased phase delay as basis. The small bias in the modified biased phase delay is estimated together with other parameters when the relative position of the rover is calculated. The effectiveness of the proposed method is confirmed using the same-beam VLBI observation data of SELENE. The radio sources onboard the rover and the lander are designed for same-beam VLBI observations. The results of the simulations of the differential delay of the same-beam VLBI observation between the rover and the lander show that the differential delay is sensitive to relative position. An approach to solving the relative position and a strategy for tracking are also introduced. When the lunar topography data near the rover are used and the observations are scheduled properly, the determined relative position of the rover may be nearly as accurate as that solved using differential phase delay data.CHEN Ming LIU QingHui WU YaJun ZHAO RongBing DAI ZhiQiang 2011Science China(Physics,Mechanics & Astronomy)2011,54,12:12
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