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3690篇 您的检索式:作者名="Zhang Wan"
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1Design of a new dynamical core for global atmospheric models based on some efficient numerical methods显示文摘A careful study on the integral properties of the primitive hydrostatic balance equations for baroclinic atmosphere is carried out, and a new scheme todesign the global adiabatic model of atmospheric dynamics ispresented. This scheme includes a method of weighted equal-areamesh and a fully discrete finite difference method with quadraticand linear conservations for solving the primitive equationsystem. Using this scheme, we established a new dynamical corewith adjustable high resolution acceptable to the availablecomputer capability, which can be very stable without anyfiltering and smoothing. Especially, some important integralproperties are kept unchanged, such as the anti-symmetries of thehorizontal advection operators and the vertical convectionoperator, the mass conservation, the effective energy conservationunder the standard stratification approximation, and so on. Somenumerical tests on the new dynamical core, respectively regardingits global conservations and its integrated performances inclimatic modeling, incorporated with the physical packagesfrom the Community Atmospheric Model Version 2 (CAM2) of NationalCenter for Atmospheric Research (NCAR), are included.WANG Bin, WAN Hui, Jl Zhongzhen, ZHANG Xin, YU Rucong, YU Yongqiang & LIU HongtaoState Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China Department of Computational Mathematics, Academy of Mathematics and System Sciences, Peking University, Beijing 100871, China 2004Science China Mathematics2004,47,z1:92
2Isolation and initial characterization of GW5, a major QTL associated with rice grain width and weight显示文摘谷物重量是庄稼谷物产量的一个主要决定因素并且被自然地发生的量的特点 loci (QTL ) 控制。我们更早识别了控制米饭谷物宽度和重量的主要 QTL, GW5,它在米饭染色体 5 上被印射到一个再结合热点。获得 GW5 怎么控制米饭谷物宽度的更好的理解,我们进行了这个地点的好印射并且揭开在米饭栽培变种 Asominori 与增加的谷物宽度联系的 1 212-bp 删除,与苗条谷物米饭 IR24 比较。另外, 46 米饭栽培变种的 genotyping 分析表明这删除高度与谷物宽度显型被相关,建议 GW5 删除可能在米饭驯服期间被选择了。GW5 编码对原子核局部性的 144 氨基酸的新奇原子蛋白质。而且,我们证明 GW5 身体上在酵母与 polyubiquitin 交往二混血儿的试金。一起,我们的结果建议 GW5 代表主要 QTL 内在的米饭宽度和重量,并且它多半在 ubiquitin-proteasome 小径行动在种子开发期间调整房间分割。这研究提供新奇卓见进控制米饭谷物开发的分子的机制并且建议 GW5 能为庄稼的产量很高的繁殖用作一个潜在的工具。Jianfeng Weng Suhai Gu Xiangyuan Wan He Gao Tao Guo Ning Su Cailin Lei Xin Zhang Zhijun Cheng Xiuping Guo Jiulin Wang Ling Jiang Huqu Zhai Jianmin Wan 2008Cell Research2008,18,12:248
3Coexistence of Th1/Th2 and Thl7/Treg imbalances in patients with allergic asthma显示文摘背景高度敏化的病人的数字正在升起,并且促进感受性能导致肾移植失败。现在的学习试图在高度敏化的肾与 rituximab 调查肾的移植追随者正式就职治疗的安全和功效移植 recipients.Methods 七个高度敏化的肾移植接受者从 2008 年 12 月经历了 rituximab 治疗到 2009 年 12 月的人,回顾地被分析。有 3 个男人和 4 个女人,与 38.5 年的吝啬的年龄(范围, 21-47 年) 。hemodialysis 的持续时间是 3-12 月,与 11 个月的吝啬的持续时间。为 4 个病人,这是第二移植;以前的接枝幸存时间是 2-11 年,与 5.8 年的一吝啬的幸存时间。所有女接受者有多重怀孕的历史,并且所有病人以前收到了输血。所有施主是男人,与 32.5 年的吝啬的年龄(范围, 25-37 年) 。在 7 个病人中的 2 个,面板的一级和类 II 反应抗体高;留下 5 个病人在一级或在面板的班 II 高显示出任何一个反应抗体。吝啬的面板反应抗体价值为一级是 31% 并且 51% 为类 II 分别地。施主和接受者让同宗打字,与从 2% ~ 5%的低淋巴细胞 cytotoxicity。人的白血球抗原(HLA ) 失配数字从 2 ~ 4。所有病人收到了 tacrolimus (0.1 mg ???????湡楧杯慲桰 吗?SHI Yu-heng SHI Guo-chao WAN Huan-ying JIANG Li-hua AI Xiang-yan ZHU Hai-xing TANG Wei MA Jia-yun JIN Xiao-yan ZHANG Bo-ying 2011Chinese Medical Journal2011,,13:120
4Targeted mutagenesis in rice using CRISPR-Cas system显示文摘Jin Miao Dongshu Guo Jinzhe Zhang Qingpei Huang Genji Qin Xin Zhang Jianmin Wan Hongya Gu Li-Jia Qu 2013Cell Research2013,23,10:103
5Western North Pacific Tropical Cyclone Database Created by the China Meteorological Administration显示文摘This paper describes the access to, and the content, characteristics, and potential applications of the tropical cyclone(TC) database that is maintained and actively developed by the China Meteorological Administration, with the aim of facilitating its use in scientific research and operational services. This database records data relating to all TCs that have passed through the western North Pacific(WNP) and South China Sea(SCS) since 1949. TC data collection has expanded over recent decades via continuous TC monitoring using remote sensing and specialized field detection techniques,allowing collation of a multi-source TC database for the WNP and SCS that covers a long period, with wide coverage and many observational elements. This database now comprises a wide variety of information related to TCs, such as historical or real-time locations(i.e., best track and landfall), intensity, dynamic and thermal structures, wind strengths, precipitation amounts, and frequency. This database will support ongoing research into the processes and patterns associated with TC climatic activity and TC forecasting.Xiaoqin LU Hui YU Ming YING Bingke ZHAO Shuai ZHANG Limin LIN Lina BAI Rijin WAN 2021Advances in Atmospheric Sciences2021,38,4:96
6Evidence of crustal ‘channel flow’ in the eastern margin of Tibetan Plateau from MT measurements显示文摘Magnetotelluric (MT) survey has been carried out in the eastern margin of the Tibetan Plateau and its neighboring Shimian-Leshan area, Sichuan Province. Analysis of this MT data reveals that the electric structure of the Tibetan Plateau differ much from that of the Sichuan block. In general, the electric re-sistivity of crust beneath the Sichuan block in the east is larger than that of the eastern margin of the Tibetan Plateau in the west. The crust of the plateau is divided into upper, middle, and lower layers. The middle crust is a low resistivity layer with minimum down to 3―10 Ωm about 10―15 km thick. It pre-sumably contains partial melt and/or salt-bearing fluids with low viscosity, prone to deform and flow, producing a 'channel flow' under the southeastward squeeze of the eastern Tibetan Plateau. This low-resistivity layer makes the upper crust decoupled mechanically from the lower crust. In the brittle upper crust, faults are dominated by left-lateral strike-slip and thrust motions, leading to surface rising and shallow earthquakes. The low-resistivity layer also cut the Xianshuihe-Anninghe fault zone into two sections vertically. In this region, the thicknesses of upper, middle, and lower crust vary laterally, pro-ducing a transitional zone in the eastern margin of the Tibetan Plateau characterized by thicker crust and higher elevation in the west and thinner crust and lower elevation in the east.ZHAO GuoZe CHEN XiaoBin WANG LiFeng WANG JiJun TANG Ji WAN ZhanSheng ZHANG JiHong ZHAN Yan XIAO QiBin 2008Chinese Science Bulletin2008,53,12:57
7Efficacy of cattle encephalon glycoside and ignotin in patients with acute cerebral infarction: a randomized, double-blind, parallel-group, placebo-controlled study显示文摘Cattle encephalon glycoside and ignotin(CEGI)injection is a compound preparation formed by a combination of muscle extract from hea lthy rabbits and brain gangliosides from cattle,and it is generally used as a neuroprotectant in the treatment of central and peripheral nerve injuries.However,there is still a need for high-level clinical evidence from large samples to support the use of CEGI.We therefore carried out a prospective,multicenter,randomized,double-blind,parallel-group,placebo-controlled study in which we recruited 319 patients with acute cerebral infarction from 16 centers in China from October 2013 to May 2016.The patients were randomized at a 3:1 ratio into CEGI(n=239;155 male,84 female;61.2±9.2 years old)and placebo(n=80;46 male,34 female;63.2±8.28 years old)groups.All patients were given standard care once daily for 14 days,including a 200 mg aspirin enteric-coated tablet and 20 mg atorvastatin calcium,both taken orally,and intravenous infusion of 250–500 mL 0.9%sodium chloride containing 40 mg sodium tanshinone IIA sulfonate.Based on conventional treatment,patients in the CEGI and placebo groups were given 12 mL CEGI or 12 mL sterile water,respectively,in an intravenous drip of 250 mL 0.9%sodium chloride(2 mL/min)once daily for 14 days.According to baseline National Institutes of Health Stroke Scale scores,patients in the two groups were divided into mild and moderate subgroups.Based on the modified Rankin Scale results,the rate of patients with good outcomes in the CEGI group was higher than that in the placebo group,and the rate of disability in the CEGI group was lower than that in the placebo group on day 90 after treatment.In the CEGI group,neurological deficits were decreased on days 14 and 90 after treatment,as measured by the National Institutes of Health Stroke Scale and the Barthel Index.Subgroup analysis revealed that CEGI led to more significant improvements in moderate stroke patients.No drug-related adverse events occurred in the CEGI or placebo groups.In conclusion,CEGI may be a safe and effective treatment for acute cerebral infarction patients,especially for moderate stroke patients.This study was approved by the Ethical Committee of Peking University Third Hospital,China(approval No.2013-068-2)on May 20,2013,and registered in the Chinese Clinical Trial Registry(registration No.ChiCTR1800017937).Hui Zhang Chuan-Ling Li Feng Wan Su-Juan Wang Xiu-E Wei Yan-Lei Hao Hui-Lin Leng Jia-Min Li Zhong-Rui Yan Bao-Jun Wang Ren-Shi Xu Ting-Min Yu Li-Chun Zhou Dong-Sheng Fan 2020Neural Regeneration Research2020,15,7:54
8The Reference Genome of Tea Plant and Resequencing of 81 Diverse Accessions Provide Insights into Its Genome Evolution and Adaptation显示文摘Tea plant is an important economic crop,which is used to produce the world's oldest and most widely consumed tea beverages.Here,we present a high-quality reference genome assembly of the tea plant(Camellia sinensis var.sinensis)consisting of 15 pseudo-chromosomes.LTR retrotransposons(LTR-RTs)account for 70.38%of the genome,and we present evidence that LTR-RTS play critical roles in genome size expansion and the transcriptional diversification of tea plant genes through preferential insertion in promoter regions and introns.Genes,particularly those coding for terpene biosynthesis pro-teins,associated with tea aroma and stress resistance were significantly amplified through recent tandem duplications and exist as gene clusters in tea plant genome.Phylogenetic analysis of the sequences of 81 tea plant accessions with diverse origins revealed three well-differentiated tea plant populations,support-ing the proposition for the southwest origin of the Chinese cultivated tea plant and its later spread to western Asia through introduction.Domestication and modern breeding left significant signatures on hundreds of genes in the tea plant genome,particularly those associated with tea quality and stress resis-tance.The genomic sequences of the reported reference and resequenced tea plant accessions provide valuable resources for future functional genomics study and molecular breeding of improved cul-tivars of tea plants.Enhua Xia Wei Tong Yan Hou Yanlin An Linbo Chen Qiong Wu Yunlong Liu Jie Yu Fangdong Li Ruopei Li Penghui Li Huijuan Zhao Ruoheng Ge Jin Huang Ali Inayat Mallano Yanrui Zhang Shengrui Liu Weiwei Deng Chuankui Song Zhaoliang Zhang Jian Zhao Shu Wei Zhengzhu Zhang Tao Xia Chaoling Wei Xiaochun Wan 2020Molecular Plant2020,13,7:51
9SHRIMP ages of detrital zircons from the Changcheng System in the Ming Tombs area,Beijing:Constraints on the protolith nature and maximum depositional age of the Mesoproterozoic cover of the North China Craton显示文摘The Mesoproterozoic Changcheng System is widely distributed in the North China Craton. Determining its time of deposition and sources is important to understand the Precambrian crustal evolution of the North China Craton. This paper suggests age distribution patterns for detrital zircons from clastic sediments of the Changcheng System in the Ming Tombs area, Beijing. Samples of feldspar-bearing sandstone (CHc-2) and pure sandstone (CHc-9) were collected from the Changzhougou Formation, which constitutes the basal part of the Changcheng System. Detrital zircons show an age range from 2.35 to 2.60 Ga. However, sample CHc-9 in the upper Changzhougou Formation also contains some zircons with ages of 1.9-1.8 Ga and 2.3-2.1 Ga. The age patterns lead to the following conclusions: (1) Most of the detrital material came from a source area composed predominantly of ~2.5 Ga continental crust of the North China Craton; (2) 1.9-1.8 Ga reflects the age record of Palaeoproterozoic continent-continent collisional event in the North China Craton; and (3) the oldest age for deposition of the Changcheng System is 1.8 Ga.WAN Yusheng1,2, ZHANG Qiaoda1 & SONG Tianrui1 1. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2. Beijing SHRIMP Laboratory, Beijing 100037, China Correspondence should be addressed to Wan Yusheng (e-mail: wanyusheng@cags.net.cn) 2003Chinese Science Bulletin2003,48,22:60
10SHRIMP zircon U-Pb dating for subduction-related gran-itic rocks in the northern part of east Junggar, Xinjiang显示文摘SHRIMP U-Pb zircon dating on the Xileketehalasu granodiorite porphyry and Kalasayi monodiorite porphyry that intrude middle Devonian Beitashan Formation at the north part of east Junggar region shows that they were formed at 381±6 Ma and 376±10 Ma respectively. They are interpreted as subduction-related granitic rocks, which is the first report that the isotopic ages for the granitic rocks range from 350 to 390 Ma. Another determined age for the Kalasayi monodiorite porphyry is 408±9 Ma, representing the age of underlain Lower Devonian volcanic rocks. Thus, the U-Pb dates suggest that the northeastward subduction of Junggar ocean from southwest occurred at 408 to 376 Ma (the real inter- val may be larger). Because the ore-bearing porphyry intruded following the formation of the volcanic rocks of middle Devonian Beitashan Formation, their tec- tonic setting is similar to the Andes Mountains that hosts world-class porphyry copper deposits, and the researched area could be regarded as a potential area for prospecting large porphyry copper deposits.ZHANG Zhaochong YAN Shenghao CHEN Bailin ZHOU Gang HE Yongkang CHAI Fengmei HE Lixin WAN Yusheng 2006Chinese Science Bulletin2006,51,8:43
11SHRIMP U-Pb geochronology of the zircons from the Precambrian basement of the Qilian Block and its geological significances显示文摘Origin and tectonic evolution of the Qilian Precambrian basement on NW China were investigated using zircon U-Pb ages with collaborating stratigraphic and paleontological evidence. Zircon grains were separated from two schists, two granitic gneisses and one mylonized gneiss and dated with SHRIMP. Seventy percent of sixty-one detrital zircon ages from two schists ranges from 0.88 Ga to 3.09 Ga, mostly within 1.0 Ga to 1.8 Ga with a peak at 1.6 Ga to 1.8 Ga, and twenty percent varies from 2.0 Ga to 2.5 Ga. A few falls in the Archean and Neoproterozoic periods. The two granitic gneisses were dated 930±8 Ma and 918±14 Ma, whereas the mylonized granitic gneiss was dated 790±12 Ma. These ages represent two periods of magmatisms, which can be correlated with the early and late stages of magmatisms associated with the Jinningian movement on the Yangtze Blocks. The results from this and previous studies indicate that the ages of the Precambrian detrital zircons from the Qilian Block are widely distributed in the Proterozoic era, distinct from the North China Block which was stable in the Neo-Mesoproterozoic era. By contrast, the age histograms of the detrital zircons from the Qilian Block is similar to those from Precambrian basement of the Yangtze Craton. Therefore, it is suggested that the Qilian Block had a strong affinity toward the Yangtze Craton and might belong to the supercontinent Gondwana in the Neoproterozoic time. This inference is supported by Nd model age (TDM), stratigraphic, and paleontological evidence. It is further considered that the Qilian Block was rifted from the supercontinent Gondwana during late Sinian to form an isolated continent in the Proto-Tethyan Ocean, moving towards the Alaxa Block in the North China Craton. The part of Proto-Tethyan Ocean between the Qilian and Alaxa Blocks should correspond to the so-called Paleo-Qilian Ocean. Following the closure of the Paleo-Qilian Ocean in the early Paleozoic, the Qilian Block collided with the Alaxa Block to form the North Qilian Orogenic Belt. Based on this tectonic explanation, the North Qilian ophiolites should represent parts of lithosphere from the Proto-Tethyan Ocean. Lithological and geochronological evidence also indicates that the Qilian Block underwent continental reactivation possibly induced by the deep northward subduction of the North Qaidam Block in early Paleozoic time.Kuoan TUNG Huai-Jen YANG Houng-Yi YANG LIU DunYi ZHANG JianXin WAN YuSheng Chien-Yuan TSENG 2007Chinese Science Bulletin2007,52,19:42
12A multicenter, phase III trial of hemocoagulase Agkistrodon: hemostasis, coagulation, and safety in patients undergoing abdominal surgery显示文摘为注射的背景 Hemocoagulase Agkistrodon 是传递了阶段的单个部件凝血酵素我和 II 临床的选拔赛。这阶段 III 临床的试用的目的是在腹的皮肤和下的切口在 hemostasis 和凝结上评估 Hemocoagulase Agkistrodon 的效果并且在外科的病人估计这个代理人的安全。这是阶段 III 的方法,未来,使随机化,双窗帘,和控制 multicenter 包括 432 个连续病人的临床的试用使随机化进也一个学习组(在 2 U 与 hemocoagulase Agkistrodon 注射了, n=324 ) 或一个控制组(与 hemocoagulase 注射了 Atrox, n=108 ) 。止血时间,出血性的体积,出血性的体积在二个组之间每统一区域,血凝结,和不利事件被测量并且比较。在学习组的吝啬的止血时间是的结果(36.8 整 ? 桰獡 ??? 牴慩? 景栠浥 ' 覒 ^ 畧慬敳 ? 歧獩牴摯湯栺浥獯慴楳? 潣条汵瑡潩 ? 湡 ? 慳敦祴椠 ? 慰楴湥獴甠摮牥潧湩 ?L 潤業慮??杲牥 y 琠??WEI Jun-min ZHU Ming-wei ZHANG Zhong-tao JIA Zhen-geng HE Xiao-dong WAN Yuan-lian WANG Shan XIU Dian-rong TANG Yun LI Jie XU Jing-yong ZHENG Qing-shan 2010Chinese Medical Journal2010,,5:43
13Ages and Compositions of the Precambrian High-grade Basement of the Qilian Terrane and Its Adjacent Areas显示文摘Based on geological, chronological, geochemical and Nd isotopicstudies of the high-grade basement of the Qilian terrane, the authors have drawn the following main conclusions: (1) the high-grade basement of the Qilian terrane consists mainly of meta-argillo-arenaceous rocks and granites and its bulk part was formed in the period of 0.8-1.0 Ga (the Jinningian period); (2) most of the meta-argillo-arenaceous rocks and granitic rocks have strong negative Eu and Ba anomalies (Eu/Eu*= 0.47-0.71 and Ba/Ba*= 0.16-0.64), with tDM and εNd (1.0 Ga) ranging from 1.87 to 2.26 Ga and from -8.54 to -4.06 respectively, showing relatively high maturity; and (3) the Jinningian granitic rocks are a typical product of continent-continent collision, being probably related to the formation of the supercontinent Rodinia. These studies, com bined with the study of high-grade basement rocks near the Qilian terrane, suggest that before the Jinningian period, the Qilian-Qaidam northern-margin terrane and Dunhuang-Alxa terrane were separated from each other, belonging to differ ent plate systems of the North China craton and Yangtze platform respectively. The Qilian orogenic belt was the same as or similar to the Qiling orogenic belt in terms of the geological evolution history at least before the Jinningian period.WAN Yusheng, XU Zhiqin, YANG Jingsui and ZHANG Jianxin Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037 2001Acta Geologica Sinica(English Edition)2001,75,4:40
14Strategies of minimally invasive treatment for intrahepatic and extrahepatic bile duct stones显示文摘Zongming Zhang Zhuo Liu Limin Liu Mengmeng Song Chong Zhang Hongwei Yu Baijiang Wan Mingwen Zhu Zixu Liu Hai Deng Haiming Yuan Haiyan Yang Wenping Wei Yue Zhao 2017Frontiers of Medicine2017,11,4:37
15Anisotropic coding metamaterials and their powerful manipulation of differently polarized terahertz waves显示文摘Metamaterials based on effective media can be used to produce a number of unusual physical properties(for example,negative refraction and invisibility cloaking)because they can be tailored with effective medium parameters that do not occur in nature.Recently,the use of coding metamaterials has been suggested for the control of electromagnetic waves through the design of coding sequences using digital elements‘0’and‘1,'which possess opposite phase responses.Here we propose the concept of an anisotropic coding metamaterial in which the coding behaviors in different directions are dependent on the polarization status of the electromagnetic waves.We experimentally demonstrate an ultrathin and flexible polarization-controlled anisotropic coding metasurface that functions in the terahertz regime using specially designed coding elements.By encoding the elements with elaborately designed coding sequences(both 1-bit and 2-bit sequences),the x-and y-polarized waves can be anomalously reflected or independently diffused in three dimensions.The simulated far-field scattering patterns and near-field distributions are presented to illustrate the dual-functional performance of the encoded metasurface,and the results are consistent with the measured results.We further demonstrate the ability of the anisotropic coding metasurfaces to generate a beam splitter and realize simultaneous anomalous reflections and polarization conversions,thus providing powerful control of differently polarized electromagnetic waves.The proposed method enables versatile beam behaviors under orthogonal polarizations using a single metasurface and has the potential for use in the development of interesting terahertz devices.Shuo Liu Tie Jun Cui Quan Xu Di Bao Liangliang Du Xiang Wan Wen Xuan Tang Chunmei Ouyang Xiao Yang Zhou Hao Yuan Hui Feng Ma Wei Xiang Jiang Jiaguang Han Weili Zhang Qiang Cheng 2016Light(Science & Applications)2016,5,1:36
16A meta-analysis of oxidative stress markers in schizophrenia显示文摘Oxidative stress has been identified as a possible element in the neuropathological processes of schizophrenia(SCZ).Alteration of oxidative stress markers has been reported in SCZ studies,but with inconsistent results.To evaluate the risk of oxidative stress to schizophrenia,a meta-analysis was conducted,including five markers of oxidative stress [thiobarbituric reactive substances(TBARS),nitric oxide(NO),catalase(CAT),glutathione peroxidase(GP) and superoxide dismutase(SOD)] in SCZ patients versus healthy controls.This study showed that TBARS and NO significantly increased in SCZ,while SOD activity significantly decreased in the disorganized type of SCZ patients.No significant effect size was found for the activities of GP and CAT in SCZ patients(P>0.05).Egger’s regression test observed no significant publication bias across the oxidative stress markers,but found high heterogeneities in all the 5 markers.The subgroup analysis suggested that the ethnicity,sample size of patients and sample sources may contribute to the heterogeneity of the results for TBARS,NO and SOD.The result further demonstrated the involvement of oxidative stress in the pathophysiology of schizophrenia.ZHANG Ming1,2,ZHAO ZhongMing3,HE Lin1,2,4 & WAN ChunLing1,2 1 Bio-X Center,Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders(Ministry of Education),Shanghai Jiao Tong University,Shanghai 200030,China 2 Institutes for Nutritional Sciences,Shanghai Institute of Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China 3 Departments of Biomedical Informatics,Psychiatry,and Cancer Biology,Vanderbilt University Medical Center,Nashville,TN 37232,USA 4 Institutes of Biomedical Sciences,Fudan University,Shanghai 200032,China 2010Science China(Life Sciences)2010,53,1:32
17Polycyclic aromatic hydrocarbons in soils of Beijing and Tianjin region: Vertical distribution, correlation with TOC and transport mechanism显示文摘The contents and distribution of 20 polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatic hydrocarbons (HAHs) were investigated in 16 soil profiles of Beijing and Tianjin region. Transport of high molecular weight PAHs (HMWPAHs) and the correlation between total organic carbon (TOC) and their concentrations were also discussed. The results indicated that highly contaminated sites were located at urban or wastewater irrigation areas and pollutants mainly accumulated in topsoil (< 40 cm), with a sharp content decrease at the vertical boundary of 30-40 cm. Total PAHs/HAHs concentrations in soils from Tianjin were markedly greater than those from Beijing. Even the contents at bottoms of soil profiles in Tianjin were higher than those in topsoils of Beijing soil profile. HMWPAHs dominated the PAH profiles, exhibiting a uniform distribution of pyrogenic origin between topsoils and deep layers. Furthermore, the percentages of HMWPAHs remained relative constant with the depth of soil profiles, which were consistent with the distribution of particulate matter-associated PAHs in the local atmospheric environments. Therefore, HMWPAHs transport with particulates might be the predominant source found in soil profiles.HE Fengpeng ZHANG Zhihuan WAN Yunyang LU Song WANG Liang BU Qingwei 2009Journal of Environmental Sciences2009,21,5:34
18济南市机构养老服务的定性研究:老年护理人员现状显示文摘分析机构养老服务利益相关者对济南市养老机构老年护理人员队伍现状的认识。方法:采用焦点小组访谈的方法,分别对政府官员、养老机构管理人员、养老机构工作人员,入住养老机构的老年人以及社区老年人进行访谈。结果:养老机构中的老年护理人员多为下岗或农村务工人员,普遍缺少专业教育背景,养老机构对老年护理人员的培训还处于'以师带徒'的阶段。人员管理存在诸多困难和问题。结论:养老机构老年护理人员队伍层次较低,职业化和专业化教育滞后,人员管理需进一步加强。吴敏 李士雪 Ning Jackie Zhang 朱嫒嫒 宁博 Thomas Wan Lynn Unruh 2010中国卫生事业管理2010,27,11:32
19Adakitic rocks and destruction of the North China Craton:Evidence from experimental petrology and geochemistry显示文摘The general temporal-spatial consistency for the formation of adakitic rocks and lithospheric thinning in northern China provide a window to examine the processes and mechanism for the destruction of the North China Craton.With experimental petrology data,this paper demonstrates that the adakitic rocks in northern China are the products of partial melting of middle-to high-potassic metabasalts at the base of the lower continent crust.Based on the TiO2 solubility model,many adakitic rocks in Dabie,Jiaodong and the northern part of the craton appear to have been saturated with TiO2.This indicates the presence of a Ti-rich accessory phase in their source regions.This phase must be rutile based on the decreasing Nb/La with increasing La/Yb in the adakitic rocks.The adakitic magmas were,thus,derived from a depth of more than 50 km,based on pressures (higher than 1.5 GPa) for the stability of rutile in a metabasalt system.Because present-day crustal thickness is generally only 35 km,we suggest that the destruction of the North China Craton may have led to at least 15 km of thinning or delamination of the crust.XIONG XiaoLin LIU XingCheng ZHU ZhiMin LI Yuan XIAO Wan Sheng SONG MaoShuang ZHANG Sheng WU JinHua 2011Science China Earth Sciences2011,54,6:34
20How many sutures in the southern Central Asian Orogenic Belt:Insights from East Xinjiang-West Gansu(NW China)?显示文摘How ophiolitic mèlanges can be defined as sutures is controversial with regard to accretionary orogenesis and continental growth.The Chinese Altay,East junggar,Tianshan,and Beishan belts of the southern Central Asian Orogenic Belt(CAOB) in Northwest China,offer a special natural laboratory to resolve this puzzle.In the Chinese Altay,the Erqis unit consists of ophiolitic melanges and coherent assemblages,forming a Paleozoic accretionary complex.At least two ophiolitic melanges(Armantai,and Kelameili) in East Junggar,characterized by imbricated ophiolitic melanges,Nb-enriched basalts,adakitic rocks and volcanic rocks,belong to a Devonian-Carboniferous intra-oceanic island arc with some Paleozoic ophiolites,superimposed by Permian arc volcanism.In the Tianshan,ophiolitic melanges like Kanggurtag,North Tianshan,and South Tianshan occur as part of some Paleozoic accretionary complexes related to amalgamation of arc terranes.In the Beishan there are also several ophiolitic melanges,including the Hongshishan,Xingxingxia-Shibangjing,Hongliuhe-Xichangjing,and Liuyuan ophiolitic units.Most ophiolitic melanges in the study area are characterized by ultramafic,mafic and other components,which are juxtaposed,or even emplaced as lenses and knockers in a matrix of some coherent units.The tectonic settings of various components are different,and some adjacent units in the same melange show contrasting different tectonic settings.The formation ages of these various components are in a wide spectrum,varying from Neoproterozoic to Permian.Therefore we cannot assume that these ophiolitic melanges always form in linear sutures as a result of the closure of specific oceans.Often the ophiolitic components formed either as the substrate of intra-oceanic arcs,or were accreted as lenses or knockers in subduction-accretion complexes.Using published age and paleogeographic constraints,we propose the presence of (1) a major early Paleozoic tectonic boundary that separates the Chinese Altay-East Junggar multiple subduction systems of the southern Siberian active margin from those of the northern Tarim;and (2) a major Permian suture zone that separates the Tianshan-Beishan from the northern active margin of the Tarim Craton.These new observations and interpretations have broad implications for the architecture and crustal growth of central Asia and other ancient orogens as well.Wenjiao Xiao Chunming Han Wei Liu Bo Wan Ji'en Zhang Songjian Ao Zhiyong Zhang Dongfang Song Zhonghua Tian Jun Luo 2014Geoscience Frontiers2014,5,4:31
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