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12019新型冠状病毒基因组特征和流行病学:病毒起源和受体结合的意义显示文摘研究者对来自9例新型冠状病毒肺炎住院患者的支气管肺泡灌洗液样本和培养的分离株进行了下一代测序。从这些个体中获得了严重急性呼吸综合征-冠状病毒2(severe acute respiratory syndrome-coronavirus 2,SARS-CoV-2)的完整和部分基因组序列。利用Sanger测序连接病毒重叠群以获得全长基因组,cDNA末端快速扩增确定终端区。对这些SARSCoV-2基因组和其他冠状病毒基因组进行了系统进化分析,以确定该病毒的进化史并有助于推断其可能的起源。刘青(译) 刘莉(审校) Lu R Zhao X Li J Niu P Yang B Wu H Wang W Song H Huang B Zhu N Bi Y Ma X Zhan F Wang L Hu T Zhou H Hu Z Zhou W Zhao L Chen J Meng Y Wang J Lin Y Yuan J Xie Z Ma J Liu WJ Wang D Xu W Holmes EC Gao GF Wu G Chen W Shi W Tan W 2020中华高血压杂志2020,28,3:516
2Association of N-terminal pro-brain natriuretic peptide with the severity of coronary artery disease in patients with normal left ventricular ejection fraction显示文摘Wu NQ Guo YL Li XL Liu J Qing P Xu RX Zhu CG Jia Y J Liu G Dong Q Jiang LX Li J J Ma FL 2014Chinese Medical Journal2014,,4:23
3辛醇磷酸酯的合成与应用显示文摘以辛醇、五氧化二磷为原料合成辛醇磷酸酯 ,讨论了各种因素的影响 ,得出了最佳工艺条件 :n(辛醇 )∶n(五氧化二磷 ) =(2 5~ 3 5 )∶1.0 ,酯化时间 3~ 4h ,酯化温度 6 0~ 70℃ 。徐沛楷 李建军 SHEN G uang-xia XU Pei-kai LI Jian-jun 2001精细化工2001,18,4:11
4Spatial-temporal dynamics of desert vegetation and its responses to climatic variations over the last three decades:a case study of Hexi region in Northwest China显示文摘Analysis of spatial-temporal variations of desert vegetation under the background of climate changes can provide references for ecological restoration in arid and semi-arid areas.In this study,we used the Global Inventory Modeling and Mapping Studies(GIMMS)NDVI data from 1982 to 2006 and Moderate Resolution Imaging Spectroradiometer(MODIS)NDVI data from 2000 to 2013 to reveal the dynamics of desert vegetation in Hexi region of Northwest China over the past three decades.We also used the annual temperature and precipitation data acquired from the Chinese meteorological stations to analyze the response of desert vegetation to climatic variations.The average value of NDVImax(the maximum NDVI during the growing season)for desert vegetation in Hexi region increased at the rate of 0.65×10–3/a(P<0.05)from 1982 to 2013,and the significant increases of NDVImax mainly appeared in the typical desert vegetation areas.Vegetation was significantly improved in the lower reaches of Shule and Shiyang river basins,and the weighted mean center of desert vegetation mainly shifted toward the lower reaches of the two basins.Almost 95.32% of the total desert vegetation area showed positive correlation between NDVImax and annual precipitation,indicating that precipitation is the key factor for desert vegetation growth in the entire study area.Moreover,the areas with non-significant positive correlation between NDVImax and annual precipitation mainly located in the lower reaches of Shiyang and Shule river basins,this may be due to human activities.Only 7.64% of the desert vegetation showed significant positive correlation between NDVImax and annual precipitation in the Shule River Basin(an extremely arid area),indicating that precipitation is not the most important factor for vegetation growth in this basin,and further studies are needed to investigate the mechanism for this phenomenon.YANG Xuemei LIU Shizeng YANG Taibao XU Xianying KANG Caizhou TANG Jinnian WEI Huaidong Mihretab G GHEBREZGABHER LI Zhiqi 2016Journal of Arid Land2016,8,4:10
5Acute interstitial edematous pancreatitis:Findings on non-enhanced MR imaging显示文摘AIM: To study the appearances of acute interstitial edematous pancreatitis (IEP) on non-enhanced MR imaging. METHODS: A total of 53 patients with IEP diagnosed by clinical features and laboratory findings were underwent MR imaging. MR imaging sequences included fast spoiled gradient echo (FSPGR) fat saturation axial T1-weighted imaging, gradient echo T1-weighted (in phase), single shot fast spin echo (SSFSE) T2-weighted, respiratory triggered (R-T) T2-weighted with fat saturation, and MR cholangiopancreatography. Using the MR severity score index, pancreatitis was graded as mild (0-2 points), moderate (3-6 points) and severe (7-10 points). RESULTS: Among the 53 patients, IEP was graded as mild in 37 patients and as moderate in 16 patients. Forty-seven of 53 (89%) patients had at least one abnormality on MR images. Pancreas was hypointense relative to liver on FSPGR T1-weighted images in 18.9% of patients, and hyperintense in 25% and 30% on SSFSE T2-weighted and R-T T2-weighted images, respectively. The prevalences of the findings of IEP on R-T T2- weighted images were, respectively, 85% for pancreatic fascial plane, 77% for left renal fascial plane, 55% for peripancreatic fat stranding, 42% for right renal fascial plane, 45% for perivascular fluid, 40% for thickened pancreatic lobular septum and 25% for peripancreatic fluid, which were markedly higher than those on in-phase or SSFSE T2-weighted images (P < 0.001).CONCLUSION: IEP primarily manifests on non-enhanced MR images as thickened pancreatic fascial plane, left renal fascial plane, peripancreatic fat stranding, and peripancreatic fluid. R-T T2-weighted imaging is more sensitive than in-phase and SSFSE T2-weighted imaging for depicting IEP.Xiao-Ming Zhang Zhi-Song Feng Qiong-Hui Zhao Chun-Ming Xiao Donald G Mitchell Jian Shu Nan-Lin Zeng Xiao-Xue Xu Jun-Yang Lei Xiao-Bing Tian 2006World Journal of Gastroenterology2006,12,36:9
6PIV measurements of turbulent jets issuing from triangular and circular orifice plates显示文摘The present study experimentally investigated the near-field flow mixing characteristics of two turbulent jets issuing from equilateral triangular and circular orifice plates into effectively unbounded surroundings,respectively.Planar particle image velocimetry(PIV) was applied to measure the velocity field at the same Reynolds number of Re=50,000,where Re = UeDe /with Ue being the exit bulk velocity and the kinematic viscosity of fluid,D e the equivalent diameters.The instantaneous velocity,mean velocity,Reynolds stresses were obtained.From the mean velocity field,the centreline velocity decay rate and half-velocity width were derived.Comparing the mixing characteristics of the two jets,it is found that the triangular jet has a faster mixing rate than the circular counterpart.The triangular jet entrainments with the ambient fluid at a higher rate in the near field.This is evidenced by a shorter unmixed core,faster Reynolds stress and centreline turbulence intensity growth.The primary coherent structures in the near field are found to break down more rapidly in the triangular jet as compared to the circular jet.Over the entire measurement region,the triangular jet maintained a higher rate of decay and spread.Moreover,all components of Reynolds stress of the triangular jet appear to reach their peaks earlier,and then decay more rapidly than those of the circular jet.In addition,the axis-switching phenomenon is observed in the triangular jet.XU MinYi ZHANG JianPeng MI JianChun NATHAN G J KALT P A M 2013Science China(Physics,Mechanics & Astronomy)2013,56,6:7
7DEFORMATION AND FRACTURE MECHANISMS OF TWO-PHASE TiAl-BASED ALLOYS WITH FULLY LAMELLAR MICROSTRUCTURE显示文摘DEFORMATIONANDFRACTUREMECHANISMSOFTWO-PHASETiAl-BASEDALLOYSWITHFULLYLAMELLARMICROSTRUCTUREY.G.Zhang,C.Q.Chen(BeijingUniversit...Y. G .Zhang, C. Q. Chen (Beijing University of Aeronautics and Astronautics, Beijing 100083, China)Q. Xu (Beijing Laboratory of Electron Microscopy, Chinese Academy of Sciences. Beijing,China)M. C. Chaturvedi (The University of Manitoba, Winnipeg, Manito 1995Acta Metallurgica Sinica(English Letters)1995,8,Z1:7
8Fault diagnosis model based on multi-manifold learning and PSO-SVM for machinery显示文摘Fault diagnosis technology plays an important role in the industries due to the emergency fault of a machine could bring the heavy lost for the people and the company. A fault diagnosis model based on multi-manifold learning and particle swarm optimization support vector machine(PSO-SVM) is studied. This fault diagnosis model is used for a rolling bearing experimental of three kinds faults. The results are verified that this model based on multi-manifold learning and PSO-SVM is good at the fault sensitive features acquisition with effective accuracy.Wang Hongjun Xu Xiaoli Rosen B G 2014仪器仪表学报2014,35,S2:6
9PAQR10 and PAQR11 mediate Ras signaling in the Golgi apparatus显示文摘地岬在许多细胞的活动起一个枢轴的作用,并且它的 subcellular 区分提供空间、时间的选择。这里,我们报导由二高度相应的蛋白质 PAQR10 和孕激素和 AdipoQ 受体家庭的 PAQR11 在 Golgi 仪器发信号的地岬的空间规定的一个模式。PAQR10 和 PAQR11 在 Golgi 仪器是只局部性的。PAQR10/PAQR11 的 Overexpression 刺激基础、导致 EGF 的英皇家空军之阶级最低之兵 phosphorylation 并且以一种剂量依赖者方式增加英皇家空军之阶级最低之兵目标基因的表示。PAQR10/PAQR11 的 Overexpression 显著地提高 HRas, NRas 和 KRas4A 的 Golgi 本地化,然而并非 KRas4B。PAQR10 和 PAQR11 罐头也与 HRas, NRas 和 KRas4A 交往,然而并非 KRas4B。在由 PAQR10/PAQR11 的 overexpression 的 Golgi 仪器的增加的地岬蛋白质处于一个活跃状态。一致地, PAQR10 和 PAQR11 还原剂击倒在 Golgi 仪器的刺激 EGF 的英皇家空军之阶级最低之兵 phosphorylation 和地岬激活。有趣地, PAQR10 和 PAQR11 能与 RasGRP1,地岬的 guanine 核苷酸交换蛋白质,和 RasGRP1 的增加 Golgi 本地化交往。RasGRP1 的 C1 领域为和 PAQR10/PAQR11 的 RasGRP1 的相互作用必要、足够。由 overexpressed PAQR10/PAQR11 的英皇家空军之阶级最低之兵 phosphorylation 的模拟被 RasGRP1 的 downregulation 废除。而且, PC12 房间的区别被 PAQR10/PAQR11 的 overexpression 显著地提高。一起,这研究揭开由 PAQR10 和 PAQR11 在 Golgi 仪器发信号的地岬的空间规定的一个新范例。Ting Jin Qiurong Ding Heng Huang Daqian Xu Yuhui Jiang Ben Zhou Zhenghu Li Xiaomeng Jiang Jing He Weizhong Liu Yixuan Zhang Yi Pan Zhenzhen Wang Walter G Thomas Yan Chen 2012Cell Research2012,22,4:6
10JWA regulates melanoma metastasis by integrin alpha(V)beta(3) signaling(摘要)显示文摘Bai, J Zhang, J Wu, J Shen, L Zeng, J Ding, J Wu, Y Gong, Z Li, A Xu, S Zhou, J Li, G 2010南京医科大学学报(自然科学版)2010,30,8:4
11Preferential CTL targeting of Gag is associated with relative viral control in long-term surviving HIV-1 infected former plasma donors from China显示文摘它通常被相信细胞毒素的 T 淋巴细胞(CTL ) 玩的那 CD8 + 在限制人的免疫不全病毒类型 1 的复制(HIV-1 ) 并且在决定感染的结果,和这效果可以部分优先地取决于产品是哪个 HIV 的一个关键角色指向了。在以前的血浆施主(FPD ) 的一个队探讨在 HIV-1-specific CTL 回答和病毒复制之间的关联,天真的 FPD 与 HIV-1 clade B' 紧张感染了的 143 antiretroviral 治疗与 IFN-γ 为 HIV-1-specific CTL 回答被估计;在由使用盖住整个一致 clade B proteome 的重叠的肽(OLP ) 的单个肽水平的 Elispot 试金。由使用一个枪兵的等级关联分析,当是断然相关到 CD4 计数时,我们发现在全部的病毒特定的 CTL 活动之中的作呕特定的 CTL 回答的比例相反地与病毒的负担被相关,与与增加的病毒的负担被联系并且减少的Pol特定、Env特定的回答对比, CD4 数。另外, Vpr-specifc CTL 回答显示出类似的保护的效果与作呕回答,但是与识别的低得多的频率。显著地,我们也观察了在 HLA 之间的一个协会 --*30/B*13/Cw*06 haplotype 和可能由于的更低的病毒的负担限制了作呕特定的 CTL 回答。因此,我们的数据在疾病控制表明作呕特定的 CTL 回答的突出的角色。HLA 的优点 -- 在病毒的控制的 *30/B*13/Cw*06 haplotype 可以在学习个人与作呕特定的 CTL 回答的贡献被联系。Mingming Jia Kunxue Hong Jianping Chen Yuhua Ruan Zhe Wang Bing Su Guoliang Ren Xiaoqing Zhang Zhen Liu Quanbi Zhao Dan Li Hong Peng Marcus Altfeld Bruce D Walker Xu G Yu Yiming Shao 2012Cell Research2012,22,5:3
12青少年甘油磷酸胆碱代谢和心血管病的危险因素:一项队列研究显示文摘甘油磷酸胆碱(glycerophosphocholine,GPC)代谢物可调节动脉粥样硬化,从而导致心血管病风险。临床前期心血管病可能从青春期就开始。研究人员应用靶向血清脂质组学鉴定一组新的GPC,并测试在青春期时这些GPC中的任何一种是否与心血管病传统危险因子,如过量内脏脂肪、升高的血压、胰岛素抵抗和致动脉粥样硬化血脂异常相关。Syme C Czajkowski S Shin J Abrahamowicz M Leonard G Perron M Richer L Veillette S Gaudet D Strug L Wang Y Xu H Taylor G Paus T Bennett S Pausova Z 刘莉 叶鹏 2016中华高血压杂志2016,24,10:3
13In situ analysis of major and trace elements of anhydrous minerals by LA-ICP-MS without applying an internal standard显示文摘Yongsheng Liu Zhaochu Hu Shan Gao Detlef Günther Juan Xu Changgui Gao Haihong Chen 2008Chemical Geology2008,,1:3
14全颗粒饲料对奶牛生产性能的影响显示文摘饲料中的中性洗涤纤维(NDF)含量和饲料颗粒直径是影响瘤胃功能的重要因素。试验评估了以颗粒饲料为主的奶牛瘤胃健康情况、NDF消化率和生产性能。选取8头荷斯坦母牛(336±30 d,体重346±35 kg),随机分配到交叉重复试验组中,奶牛安置于牛栏,自由采食。试验期为3周,前两周是适应期,最后一周为数据收集期。各组饲粮原料相同,但物理形式不同,分为全混合日粮(TMR)和颗粒料(直径=8 mm)。两组间物理有效NDF(pe NDF)不同,TMR组为39.8%,颗粒料组为11.8%。在试验过程中,干物质采食量(DMI)、饮水量、瘤胃反刍时间、瘤胃温度和pH情况均记录。3周后收集粪样,确定潜在的可消化NDF总消化率(pdNDF)。每阶段结束后计算平均日增重和饲料转化率。颗粒料组的DMI、DMI/体重和饮水量更高。而两组间平均日增重和饲料转化率无显著差异。颗粒料组的瘤胃反刍时间为241 min·d-1低于TMR组的507 min·d-1。饲料的不同物理外形对瘤胃温度、瘤胃pH无显著影响。TMR组的pdNDF总消化率为90.25%高于颗粒料组的86.82%。试验结果表明,动物易接受完整的颗粒饲料,DMI较高,且反刍时间减少,但瘤胃pH无显著变化。TMR组的pdNDF消化率显著增加。尽管两组奶牛在DMI和纤维消化方面表现不同,但总体表现相似,两组饲料的保存时间与其物理形式有关。在短期内,提供能满足NDF需求的完全颗粒饲料可改善瘤胃健康状况和动物生产性能,而较长时间的数据则需要进一步试验。Wang J Yang M Cao M Lin Y Che L Q Duraipandiyan V Al-Dhabi N A Fang Z F Xu S Y Feng B Liu G Wu D Bonfante E Palmonari A Mammi L Canestrari G Fustini M Formigoni A 2016饲料博览2016,0,12:2
15Fungal diversity notes 367-490:taxonomic and phylogenetic contributions to fungal taxa显示文摘This is a continuity of a series of taxonomic papers where materials are examined,described and novel combinations are proposed where necessary to improve our traditional species concepts and provide updates on their classification.In addition to extensive morphological descriptions and appropriate asexual and sexual connections,DNA sequence data are also analysed from concatenated datasets(rDNA,TEF-a,RBP2 and b-Tubulin)to infer phylogenetic relationships and substantiate systematic position of taxa within appropriate ranks.Wherever new species or combinations are being proposed,we apply an integrative approach(morphological and molecular data as well as ecological features wherever applicable).Notes on 125 fungal taxa are compiled in this paper,including eight new genera,101 new species,two new combinations,one neotype,four reference specimens,new host or distribution records for eight species and one alternative morphs.The new genera introduced in this paper are Alloarthopyrenia,Arundellina,Camarosporioides,Neomassaria,Neomassarina,Neotruncatella,Paracapsulospora and Pseudophaeosphaeria.The new species are Alfaria spartii,Alloarthopyrenia italica,Anthostomella ravenna,An.thailandica,Arthrinium paraphaeospermum,Arundellina typhae,Aspergillus koreanus,Asterina cynometrae,Bertiella ellipsoidea,Blastophorum aquaticum,Cainia globosa,Camarosporioides phragmitis,Ceramothyrium menglunense,Chaetosphaeronema achilleae,Chlamydotubeufia helicospora,Ciliochorella phanericola,Clavulinopsis aurantiaca,Colletotrichum insertae,Comoclathris italica,Coronophora myricoides,Cortinarius fulvescentoideus,Co.nymphatus,Co.pseudobulliardioides,Co.tenuifulvescens,Cunninghamella gigacellularis,Cyathus pyristriatus,Cytospora cotini,Dematiopleospora alliariae,De.cirsii,Diaporthe aseana,Di.garethjonesii,Distoseptispora multiseptata,Dis.tectonae,Dis.tectonigena,Dothiora buxi,Emericellopsis persica,Gloniopsis calami,Helicoma guttulatum,Helvella floriforma,H.oblongispora,Hermatomyces subiculosa,Juncaceicola italica,Lactarius dirkii,Lentithecium unicellulare,Le.voraginesporum,Leptosphaeria cirsii,Leptosphaeria irregularis,Leptospora galii,Le.thailandica,Lindgomyces pseudomadisonensis,Lophiotrema bambusae,Lo.fallopiae,Meliola citri-maximae,Minimelanolocus submersus,Montagnula cirsii,Mortierella fluviae,Muriphaeosphaeria ambrosiae,Neodidymelliopsis ranunculi,Neomassaria fabacearum,Neomassarina thailandica,Neomicrosphaeropsis cytisi,Neo.cytisinus,Neo.minima,Neopestalotiopsis cocoe¨s,Neopestalotiopsis musae,Neoroussoella lenispora,Neotorula submersa,Neotruncatella endophytica,Nodulosphaeria italica,Occultibambusa aquatica,Oc.chiangraiensis,Ophiocordyceps hemisphaerica,Op.lacrimoidis,Paracapsulospora metroxyli,Pestalotiopsis sequoiae,Peziza fruticosa,Pleurotrema thailandica,Poaceicola arundinis,Polyporus mangshanensis,Pseudocoleophoma typhicola,Pseudodictyosporium thailandica,Pseudophaeosphaeria rubi,Purpureocillium sodanum,Ramariopsis atlantica,Rhodocybe griseoaurantia,Rh.indica,Rh.luteobrunnea,Russula indoalba,Ru.pseudoamoenicolor,Sporidesmium aquaticivaginatum,Sp.olivaceoconidium,Sp.pyriformatum,Stagonospora forlicesenensis,Stagonosporopsis centaureae,Terriera thailandica,Tremateia arundicola,Tr.guiyangensis,Trichomerium bambusae,Tubeufia hyalospora,Tu.roseohelicospora and Wojnowicia italica.New combinations are given for Hermatomyces mirum and Pallidocercospora thailandica.A neotype is proposed for Cortinarius fulvescens.Reference specimens are given for Aquaphila albicans,Leptospora rubella,Platychora ulmi and Meliola pseudosasae,while new host or distribution records are provided for Diaporthe eres,Di.siamensis,Di.foeniculina,Dothiorella iranica,Do.sarmentorum,Do.vidmadera,Helvella tinta and Vaginatispora fuckelii,with full taxonomic details.An asexual state is also reported for the first time in Neoacanthostigma septoconstrictum.This paper contributes to a more comprehensive update and improved identification of many ascomycetes and basiodiomycetes.Kevin D.Hyde Sinang Hongsanan Rajesh Jeewon D.Jayarama Bhat Eric H.C.McKenzie E.B.Gareth Jones Rungtiwa Phookamsak Hiran A.Ariyawansa Saranyaphat Boonmee Qi Zhao Faten Awad Abdel-Aziz Mohamed A.Abdel-Wahab Supharat Banmai Putarak Chomnunti Bao-Kai Cui Dinushani A.Daranagama Kanad Das Monika C.Dayarathne Nimali Ide Silva Asha J.Dissanayake Mingkwan Doilom Anusha H.Ekanayaka Tatiana Baptista Gibertoni Aristóteles Góes-Neto Shi-Ke Huang Subashini C.Jayasiri Ruvishika S.Jayawardena Sirinapa Konta Hyang Burm Lee Wen-Jing Li Chuan-Gen Lin Jian-Kui Liu Yong-Zhong Lu Zong-Long Luo Ishara S.Manawasinghe Patinjareveettil Manimohan Ausana Mapook Tuula Niskanen Chada Norphanphoun Moslem Papizadeh Rekhani H.Perera Chayanard Phukhamsakda Christian Richter AndréL.C.Mde A.Santiago E.Ricardo Drechsler-Santos Indunil C.Senanayake Kazuaki Tanaka T.M.D.S.Tennakoon Kasun M.Thambugala Qing Tian Saowaluck Tibpromma Benjarong Thongbai Alfredo Vizzini Dhanushka N.Wanasinghe Nalin N.Wijayawardene Hai-Xia Wu Jing Yang Xiang-Yu Zeng Huang Zhang Jin-Feng Zhang Timur S.Bulgakov Erio Camporesi Ali H.Bahkali Mohammad A.Amoozegar Lidia Silva Araujo-Neta Joseph F.Ammirati Abhishek Baghela R.P.Bhatt Dimitar Bojantchev Bart Buyck Gladstone Alves da Silva Catarina Letícia Ferreira de Lima Rafael JoséVilela de Oliveira Carlos Alberto Fragoso de Souza Yu-Cheng Dai Bálint Dima Tham Thi Duong Enrico Ercole Fernando Mafalda-Freire Aniket Ghosh Akira Hashimoto Sutakorn Kamolhan Ji-Chuan Kang Samantha C.Karunarathna Paul M.Kirk Ilkka Kytovuori Angela Lantieri Kare Liimatainen Zuo-Yi Liu Xing-Zhong Liu Robert Lücking Gianfranco Medardi Peter E.Mortimer Thi Thuong Thuong Nguyen Itthayakorn Promputtha K.N.Anil Raj Mateus A.Reck Saisamorn Lumyong Seyed Abolhassan Shahzadeh-Fazeli Marc Stadler Mohammad Reza Soudi Hong-Yan Su Takumasa Takahashi Narumon Tangthirasunun Priyanka Uniyal Yong Wang Ting-Chi Wen Jian-Chu Xu Zhong-Kai Zhang Yong-Chang Zhao Jun-Liang Zhou Lin Zhu 2016Fungal Diversity2016,,5:2
16Two closely linked rice U14 boxC/D snoRNAsJiang, G Xu, F Jin, YX Wang, DB 2002Progress in Natural Science:Materials International2002,12,1:2
17Cropping Pattern Modifications Change Water Resource Demands in the Beijing Metropolitan Area显示文摘Adequate freshwater supply has become an issue of increasing local and international concern.Reducing water use in agriculture,which is the largest water using sector of the economy,is both important and urgent.The aim of this paper was to quantify how recent cropping pattern changes have influenced water resources in the great Beijing metropolitan area,an expanding megacity which also includes rural counties.Crop production affects blue water use through water consumption and water pollution,the latter assessed here using a critical dilution method.From 1990 to 2010,the total blue water used by crop production declined due to a decrease in overall cropped area,initially in response to local government policies favouring urban development.However,the average blue water use per hectare increased from 2 112 m3 ha-1 yr-1 in 1990 to 2 764 m3 ha-1 yr-1 in 2003,largely as the result of a transition from cereal to vegetable crops,and in particular an increase in intensively managed plastic and glass covered vegetable production systems.Current policies aim to conserve agricultural land,in the interests of food security,and to stimulate cereal production systems with higher ecosystem services provision.As such,in 2010 the average blue water use was 2 425 m3 ha-1 yr-1.These results demonstrate that cropping pattern changes in peri-urban regions and rural communities surrounding the Beijing metropolitan area can have a substantial impact on water resources.They also highlight the tradeoffs between food production and urban and industrial water supply and the need for integrated policy development.HUANG Jing Bradley G Ridoutt XU Chang-chun ZHANGHai-lin CHEN Fu 2012Journal of Integrative Agriculture2012,11,11:2
18降低哈德逊混输管道段塞影响的模拟研究和现场测试显示文摘对哈德逊混输管道由段塞引起停输的模拟研究和现场测试 ,研究段塞对管输的影响规律和降低段塞影响的方法。其目的有两个 :一是验证模拟工具能否准确地预测段塞特性 ;二是为设计降低段塞影响的方法提供基础数据。模拟工具为瞬态多相流模拟器OLGA。现场测试和模拟结果表明 :段塞不是由立管引起的 ,而是由于管道操作条件处于水力段塞流的范围内引起的 ;由OLGA计算出的段塞分布同测试结果非常一致 ;还可以通过改进液位控制的方法来消除段塞引起的停输 ,这一点在其后的生产中得到验证。Z G XU P GAYTON 韩方勇 2001国外油田工程2001,17,8:2
19高血压患者血清磷酸盐与新发高尿酸血症风险的关系显示文摘血清磷酸盐与新发高尿酸血症的关系仍不确定。该研究对中国脑卒中一级预防试验(China stroke primary prevention trial,CSPPT)的尿酸亚组研究进行事后分析,旨在评估血清磷酸盐与新发高血尿酸症的风险之间的关系。研究包括基线尿酸水平正常(<357μmol/L)的参与者共10612人。主要观察指标是新发高血尿酸症,其定义为男性血尿酸浓度≥417或女性≥357μmol/L。在中位数为4.4年的随访期间,1663名(15.7%)参与者发生了新发高尿酸血症。刘莉(译) 叶鹏(摘、审校) Cao J Zhang J Li Q Jiang C Song Y Liu C Liu L Wang B Li J Zhang Y Cui Y Huo Y Wang X Tang G Xu X Qin X 2019中华高血压杂志2019,27,6:2
20On solutions of matrix equation AXB+CVD=F显示文摘Xu G Wei M Zheng D 1998Linear Algebra Appl1998,279,:2
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