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Seed Dynamics in Relation to Gaps in a Tropical Montane Rainforest of Hainan Island,South China:(II)Seed Bank

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Journal of Integrative Plant Biology 2008年第5期50卷 513-521页

作者： Run-Guo Zang Yi Ding wei-yin zhang Key Laboratory of Forest Ecology and Environment The State Forestry Administration Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Beijing 100091 China

Spatial and temporal patterns of seed bank dynamics in relation to gaps in an old growth tropical montane rainforest of Hainan Island, South China, were studied over two consecutive years. From June 2001 to June 2003, soil seed bank sampling blocks were taken near each of the four sides of each seed trap and immediately put into a nursery for observation of seedling emergence dynamics in four seasons （each experiment in each season）. The abundances of seedlings that emerged from seed banks showed the trend of vine functional group （VFG）〉 shrub functional group （SFG）〉 tree functional group （TFG）〉 herb functional group （HFG）, but the trend in species richness of seedlings that emerged from the soil seed banks was TFG 〉 VFG 〉 SFG 〉 HFG. The abundances of seedlings that emerged from seed banks in the three gap zones showed no significant differences, but significant differences did exist for the species richness. The time of sampling or seasons of experiments had significant influences on both the species richness and seedling abundances. The seedling emergence processes of each experiment all revealed the unimodal patterns. Few emergences occurred 1 year after each experiment. Compared with those under closed canopies, the recruitment rates from seed to seedlings and from seedlings to saplings In gaps were higher, but the mortality rates from saplings to big trees were also higher in the gaps.

关键词： functional groups gap dynamics Hainan Island regeneration niche seed bank supply-side ecology tropical montane rainforest.

Remote-controlled module-assisted synthesis of O-(2-[^(18)F]fluoroethyl)-L-tyrosine as tumor PET tracer using two different radiochemical routes

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Nuclear Science and Techniques 2006年第3期17卷 148-153页

作者： WANG Ming-wei yin Duan-Zhi zhang Lan ZHOU wei WANG Yong-Xian Radiopharmaceutical Centre Shanghai Institute of Applied Physics the Chinese Academy of Sciences Shanghai 201800 China

The positron-emitter fluorine-18 labeled amino acid O-(2-[18F]fluoroethyl)-L-tyrosine ([18F]FET) has shown very promising perspectives for brain tumor diagnosis with positron emission tomography (PET). There have been two existing preparation routes of [18F]FET named direct nucleophilic radiofluorination of protected L-tyrosine and radiofluoroalkylation of unprotected L-tyrosine, respectively. A general module was designed specifically for the routine synthesis of [18F]FET, which could be suitable for the present two chemical methods with simple modifica- tions. The fluorinated intermediates and the final product were separated and purified using solid phase extraction (SPE) on the Sep-Pak silica plus cartridge instead of the time-consuming high performance liquid chromatography (HPLC) procedures. The total synthesis time was about 50—60 min with good radiochemical yield (about 20—40%, no-decay-corrected) and good radiochemical purity (more than 97%) for both the synthetic methods.

关键词： PET 氟化作用合成模块正电子发射亲质子

Erosion-Resistant Surfaces Inspired by Tamarisk

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Journal of Bionic Engineering 2013年第4期10卷 479-487页

作者： Zhiwu Han wei yin Junqiu zhang Jialian Jiang Shichao Niu Luquan Ren Key Laboratory of Bionic Engineering (Ministry of Education China) Jilin University Changchun 130022 P. R. China

Tamarisk, a plant that thrives in arid and semi-arid regions, has adapted to blustery conditions by evolving extremely ef- fective and robust anti-erosion surface patterns. However, the details of these unique properties and their structural basis are still unexplored. In this paper, we demonstrate that the tamarisk surface only suffers minor scratches under wind-sand mixture erosion. The results show that the anti-erosion property of bionic sample, inspired by tamarisk surface with different surface morphologies, can be attributed to the flow rotating in the grooves that reduces the particle impact speed. Furthermore, the simulation and experiment on the erosion wear behavior of the bionic samples and bionic centrifugal fan blades show that the bionic surface with V-type groove exhibits the best erosion resistance. The bionic surface on centrifugal fan blades with opti- mum parameters can effectively improve anti-erosion property by 28.97%. This paper show more opportunities for bionic application in improving the anti-erosion performance of moving parts that work under dirt and sand particle environment, such as helicopter rotor blades, airplane propellers, rocket motor nozzles, and pipes that regularly wear out from erosion.

关键词： tamarisk anti-erosion numerical simulation bionic centrifugal fan blades

Ramet Population Structure of Fargesia nitida （Mitford） Keng f. et Yi in Different Successional Stands of the Subalpine Coniferous Forest in Wolong Nature Reserve

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Journal of Integrative Plant Biology 2006年第10期48卷 1147-1153页

作者： Xiao-Hong Yu Jian-Ping Tao Yuan Li Yong-Jian Wang Yi Xi wei-yin zhang Run-Guo Zang Key Laboratory of Eco-environments of Three Gorges Reservoir Region Ministry of Education School of Life Sciences Southwest University Chongqing 400715 China Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Beijing 100091 China

Forest structure and succession in Wolong Nature Reserve is influenced by the understory dwarf bamboo population. However, less is known about how the forest succession affects the dwarf bamboo population. To examine the bamboo ramet population growth of Fargesla nitida （Mltford） Keng f. et Yi and to determine how ramet population structure varies along the succession of coniferous forest, we sampled ramet populations of F. nitida from the following three successional stages：（i） a deciduous broad-leaved （BL） stand; （ii） a mixed broad-leaved coniferous （MI） stand; and （ill） a coniferous （CF） stand. We investigated the population structure, biomass allocation, and morphological characteristics of the bamboo ramet among the three stand types. Clonal ramets, constituting the bamboo population, tended to become short and small with succession. The ramet changed towards having a greater mass investment in leaves, branches and underground roots and rhizomes rather than in the culm. With respect to leaf traits, individual leaf mass and area in the BL stand were markedly bigger than those In both the MI and CF stands, except for no significant difference in specific leaf area. The age distribution showed that the bamboo population approached an older age with succession. The results demonstrate that the ramet population structure of F. nitida is unstable and its growth performance is inhibited by succession.

关键词： coniferous forest Fargesia nitida ramet population structure succession Wolong Nature Reserve

A modified method for the treatment of urethral fistula after hypospadias repair

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Asian Journal of Andrology 2012年第6期14卷 900-902页

作者： Chao Qin wei Wang Shang-Qian Wang Qiang Cao Zeng-Jun Wang Peng-Chao Li Jie Li Ning-Han Feng Li-Xin Hua Chang-Jun yin wei zhang State Key Laboratory of Reproductive Medicine Department of Urology The First Affiliated Hospital of Nanjing Medical University Nanjing 210029 China

Urethrocutaneous fistula （UCF） is a common complication of hypospadias surgery for severe hypospadias. We report our experience in the management of UCF following hypospadias surgery with a prepuce-degloving method （PDM）. Our study included 87 patients who developed UCF after hypospadias repair from May 2001 to December 2011. Either simple closure or PDM was performed to repair the fistula. In total, 61 patients underwent a simple closure or Y-V plasty of the fistula, and 26 underwent a PDM repair. The success rate was 78.7% for simple closure or Y-V plasty and 96.2% for PDM repair （P〈0.05）. PDM repair represents a good choice for UCF repair after hypospadias, and our high 96.2% success rate demonstrates its applicability.

关键词： hypospadias repair urethrocutaneous fistula

夏文化探索中的方法问题——“夏商周断代工程”结题后的反思(二)

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河北学刊 2006年第4期26卷 89-97页

作者：殷玮璋中国社会科学院考古研究所北京100710

目前,学术界公认中国历史上有个夏代。但由于文献记载太过简略,使后人对当时的社会历史状况知之甚少。在这种情况下,人们寄希望于考古工作者从地下找到夏代遗存。然而,在夏文化探索中,由于研究者的思路与所用方法不同,故而得出的结论也... 详细信息

目前,学术界公认中国历史上有个夏代。但由于文献记载太过简略,使后人对当时的社会历史状况知之甚少。在这种情况下,人们寄希望于考古工作者从地下找到夏代遗存。然而,在夏文化探索中,由于研究者的思路与所用方法不同,故而得出的结论也明显有异。由此,出现争论与分歧。于是,如何鉴别相关结论是否合理可信就成为学术界同人思索的问题。本文在对夏文化探索的现状进行回顾的基础上,围绕文化因素分析法与都城分析法,对分歧及其缘由作了详细探讨。文中还就坚持正确思路,采用科学方法。按科学规程操作对夏文化探索工作的重要性,谈了自己的看法。

关键词：夏文化探索文化因素分析法都城分析法

Expression of Nuclear Factor-Kappa-B in Mouse Enometrium Treated with Different Levels of Estridiol or Progesterone

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Journal of Reproduction and Contraception 2005年第1期16卷 29-34页

作者： Qi ZENG Jian-ping ZHOU wei zhang yin-kun LIU Obestetrics and Gynecology Hospital Fudan University Shanghai 200011 China

Objective To investigate the effect of estridiol nuclear factor-kappa-B （NF-kB） expression in and progesterone at different levels on mouse endometrium Methods Ovarioectmized mice were randomly divided into 9 groups, i.e. groups of sham operation, of estridiol only, of progesterone only and of progesterone combined with estridiol. Mice in the experimental groups accepted subcutaneous injections of estridiol or progesterone at different levels for one week. Their uteri were collected to detect the expression of NF-kB by immunohistochemical assay. Results Estridiol at a daily dose of 30 μg/kg and 100 μg/kg could significantly stimulate the expression of NF-kB in mouse endometrium（P〈0.01）, but not in an obvious dose-dependent fashion （P〉0.05）. Progesterone alone could inhibit the expression of NF-kB in cytoplasma （P〈0.01）. Combination of estridiol and progesterone could increase NF-kB expression both in cytoplasma and nuclear （P〈0.01）. Conclusion Eestridiol can up-regulate the expression of NF-kB in mouse endometrium, while progesterone exhibits down-regulation effect. This finding suggests that estridiol and progesterone might modulate the endometrium receptivity by affecting NF-kB pathway.

关键词： estridiol progesterone endometrium NF-kB mouse

Clinical study of maglignancy in renal allograft recipients

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Clinical study of maglignancy in renal allograft recipients

混合综采工作面覆岩运移规律及空间结构特征分析

2012中国器官移植大会

作者： pei lu,qiang lv,ruoyun tan,changjun yin,wei zhang,min gu 江苏省人民医院

【Objectives】To study the incidence,type and treatment of neoplasms in renal transplantation recipients.【Methods】A retrospective analysis was made on 1401 patients who received renal allographts from 1978 to 201 1 and anti-rejectiontreatmentforatleast6months.【Result】1401 recipients,17(1.21%)developed malignancies.12 patients were living longer than 1 year,and 5 patients died in 1 year incuding 2 cases of transplanted renal carcinoma,1 case of hepatocellular carcinoma,1 case of transplanted

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煤炭学报 2017年第2期42卷 388-396页

作者：殷伟张强韩晓乐孙强巨峰中国矿业大学煤炭资源与安全开采国家重点实验室江苏徐州221116 中国矿业大学深部岩土力学与地下工程国家重点实验室江苏徐州221116

基于平煤十二矿深部开采面临的排矸量大、辅助运输困难、矿区环境污染以及常规充填面产能不足工程背景,创新了矸石充填与垮落法混合综采技术并阐述了其技术内涵。采用理论分析、物理相似模拟和现场实测方法系统地研究了混合综采工作面... 详细信息

基于平煤十二矿深部开采面临的排矸量大、辅助运输困难、矿区环境污染以及常规充填面产能不足工程背景,创新了矸石充填与垮落法混合综采技术并阐述了其技术内涵。采用理论分析、物理相似模拟和现场实测方法系统地研究了混合综采工作面覆岩运移规律和空间结构特征。通过理论分析得到了不同充实率状态下混合综采工作面覆岩空间结构特征;物理相似模拟结果表明,混合综采工作面充填段基本顶仅发生弯曲下沉,而垮落段直接顶垮落、基本顶断裂,垮落段基本顶平均下沉量是充填段的4.2倍,覆岩空间结构表现出明显的非对称特征。矿压实测数据显示,充填段采场无明显的来压现象,垮落段来压现象显著,初次来压步距约30 m,周期来压步距约22 m,动载系数达1.7左右;岩层钻孔窥视结果观察到充填段顶板完整,覆岩空间结构呈现"两带"发育特征;垮落段覆岩结构呈"三带"发育特征,混合综采工作面覆岩非对称性空间结构特征显著。

关键词：混合综采矸石充填充实率覆岩空间结构