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Modeling the impact of Australian Plate drift on Southern Hemisphere climate and environment

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Chinese Science Bulletin 2005年第14期50卷 1495-1502页

作者： ZHOU Botao1,5, ZHAO Ping2. JIAN Zhimin3 & HE Jinhai4 1. Nansen-Zhu International Research Center, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., china 2. Institute of Climate and Environment, Chinese Academy of Meteoro- logical Sciences, Beijing 100081, china 3. Laboratory of Marine Geology, Tongji {2., Shanghai 2.0092. china 4. department of Atmospheric Sciences, Nanjing Institute of Meteorol- ogy, Nanjing 2.0044, china 5. Graduate School of the Chinese Academy of Sciences, Beijing 100039, china Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China Institute of Climate and Environment Chinese Academy of Meteorological Sciences Beijing 100081 China Laboratory of Marine Geology Tongji University Shanghai 200092 China department of Atmospheric Sciences Nanjing Institute of Meteorology Nanjing 210044 China

Using a global atmosphere-ocean coupled model with the present-day and 14 MaB.P. oceanic topogra- phy respectively, two experiments are implemented to inves- tigate the effect of different locations of Australian Plate on the atmospheric circulation in middle-high latitudes of the Southern Hemisphere. The results show that when Austra- lian Plate lay south at 14 MaB.P., both anticyclone circula- tions in the subtropical oceans and cyclone circulation around 60°-70°S are strengthened. Subtropical highs and circumpolar low pressure appear stronger, which results in much stronger Antarctic Oscillation and shorter period of Antarctic Oscillation Index (AOI) at 14 MaB.P. The rainfall and the surface air temperature also change correspondingly. The precipitation decreases around 40°S and increases around 60°-70°S, and the surface air temperature rises in high latitudes of the South Pacific and descends over the Weddell Sea and its north side. Besides, due to the changes of the temperatures and winds, Antarctic sea ice coverage also changes with its increasing in the Ross Sea and its west re- gions and decreasing in the Weddell Sea.

关键词：半球气候地球环球澳大利亚漂流物海洋地形学

EFFECTS OF COMBINED ADDITIONS OF TUNGSTEN AND MOLYBDENUM ON THE CREEP PROPERLIES OFFe_3Al-BASED ALLOYS

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Acta Metallurgica Sinica(English Letters) 2000年第6期13卷 1136-1140页

作者： X.Q. Yu and Y.S. Sun (department of Materials Science and Engineering, Southeast university, Nanjing 2.0096,{2.) Dep. of Materials and Eng. Southeast Univ. Nanjing 210096 China

Effects of combined additions of tungsten and molybdenum on the creep properties of Fe3AI-based alloys have been investigated. Results show that combined additions of tungsten and molybdenum increase significantly the creep rupture life of the Fe3Al base alloys at high temperature. TEM analysis of the alloys containing tungsten plus molybdenum indicates that both solid-solution strengthening and precipitation harden- ing make the significant increase of creep rupture life.

关键词： Fe3Al creep property tungsten molybde8

Small Solutions of the Congruence a_1x_1~2.a_2._2.2.a_3x_3~2.a_4x_4~2.c(mod p)

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Acta Mathematica Sinica,English Series 1998年第2期14卷 175-182页

作者： Todd Cochrane (department of mathematics,Kansas State {2.,Manhattan,KS 66506.U.S.A)(Email:cochrane@math.ksu.edu)Zheng Zhiyong (department of mathematics,Zhongshan {2.,Guangzhou 5102.5,china)(Email:addsr03@zsulink.zsu.edu.en)

For any integers a1,a2.a3,a4 and c with a1a2.3a40（mod p）,this paper shows that there exists a solution X=（x1,x2.x3,x4）∈Z4 of the congruence a1x12.a2.2.+a3x32.a4x42. c（mod p）such that ‖X‖=max{|x1|,|x2.,|x3|,|... 详细信息

For any integers a1,a2./sub>,a3,a4 and c with a1a2./sub>a3a40（mod p）,this paper shows that there exists a solution X=（x1,x2./sub>,x3,x4）∈Z4 of the congruence a1x12./sup>+a2./sup>x2./sub>2./sup>+a3x32./sup>+a4x42./sup>≡ c（mod p）such that ‖X‖=max{|x1|,|x2./sub>|,|x3|,|x4|}《p1/2./sup>logp.

关键词： Character sums Congruences

Synthesis and Herbicidal Activities of N'-(substituted pyrimidin-2.yl)-N-Substituted Phenoxyacetyl Thiourea Derivatives

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Chinese Chemical Letters 2000年第1期11卷 19-20页

作者： Si Jia XUE Jin Shan ZOU Hai Jian YANG (department of Chemistry, Central china Normal {2., Wuhan 430079) Cent china Normal Univ Dept Chem Wuhan 430079 Peoples R China

Fifteen N'-(substituted pyrimidin-2.y1)-N-substituted phenoxyacetyl thioureas were synthesized and tested for biological activities. All of them are new compounds and their structures were confirmed by IR. IHNMR. MS and elemental analysis. Some of the target compounds showed excellent inhibitory activities against root and stalk of dicotyledon plant (such as radish). and selective on monoctyledon plant (such as rice).

关键词： 4-Nitrophenoxyacetyl thiourea 2.4-dichlorophenoxyacetyl thiourea synthesis 2.chlorophenoxyacetyl thiourea 2.amino pyrimidine herbicidal activity

Muscarinic Receptor Agonists Protect Cultured Bovine Trabecular Meshwork Cells against Apoptosis Induced by Dexamethasone

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眼科学报 2004年第1期20卷 42-47页

作者： Yajuan Gu1,Shujun Zeng2.PengXin Qiu2.Yuping Wu2.Dawei Peng2.Guangmei Yan11department of Pharmacology, Zhongshan Medical College, Sun Yat-sen university, Guangzhou 510089,{2.2.hongshan Ophthalmic Center, Sun Yat-sen university, Guangzhou 510060,{2. department of Pharmacology Zhongshan Medical College Sun Yat-sen University Guangzhou 510089 China.

Purpose:To study whether muscarinic receptor agonists can protect cultured bovine trabecular meshwork cells against apoptosis induced by ***:The third to fifth passags of bovine trabecular meshwork cells were grown to confluence and incubated for 1～14 days in growth media with dexamethasone or pretreatment of pilocarpine or *** cultures were evaluated for apoptosis by phase-contrast microscopy, fluorescence microscopy, DNA laddering and flow cytometric ***:Dexamethasone (0.2.～0.96 mmol·L-1) induced apoptosis of trabecular mes-hwork cells in a dose and time-dependent *** 0.48 mmol·L-1 dexametha-sone-treatment, 1.84 mmol·L-1 of pilocarpine or 2.74 mmol·L-1 of carbachol added could significantly reduce apoptotic ***:Muscarinic receptor agonists can protect cultured bovine trabecular meshwork cells against apoptosis induced by dexamethasone. Eye Science 2.04;2.:42.47.

关键词： apoptosis dexamethasone pilocarpine carbachol trabecular meshwork glaucoma

Short-segment Barrett's esophagus and cardia intestinal metaplasia:A comparative analysis

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World Journal of Gastroenterology 2010年第48期16卷 6151-6154页

作者： Ying Chang,Digestive Endoscopic Center,Shanghai Sixth Hospital,Shanghai Jiao Tong university,Shanghai 2.02.3,china Bin Liu,{2. of Emergence Surgery,Shaanxi Provincial People’s Hospital,Xi’an 710068,Shaanxi Province,china Gui-Sheng Liu,{2. of Gastroenterology,Shaanxi Provincial People’s Hospital,Xi’an 710068,Shaanxi Province,china Tao Wang,{2. of Gastroenterology,First Hospital of Xi’ an Jiaotong university,Xi’an 710061,Shaanxi Province,china Jun Gong,{2. of Gastroenterology,Second Hospital of Xi’an Jiaotong university,Xi’an 710004,Shaanxi Province,china Digestive Endoscopic Center Shanghai Sixth Hospital Shanghai Jiao Tong University Yishan Road 600 Shanghai 200233 China. mulan929@***

AIM:To investigate the endoscopy and histology of short-segment Barrett's esophagus (SSBE) and cardia intestinal metaplasia (CIM),and their correlation with Helicobacter pylori (H. pylori) gastritis and gastroesophageal reflux disease (GERD). METHODS:Biopsy specimens were taken from 32.SSBE patients and 41 CIM patients with normal appearance of the esophagogastric junction. Eight biopsy specimens from the lower esophagus,cardia,and gastric antrum were stained with hematoxylin/eosin,Alcian blue/periodic acid-Schiff,Alcian blue/high iron diamine and Gimenez dye. Results were graded independently by one pathologist. RESULTS:The SSBE patients were younger than the CIM patients (P < 0.01). The incidence of dysplasia and incomplete intestinal metaplasia subtype was higher in SSBE patients than in CIM patients (P < 0.01). H. pylori infection was correlated with antral intestinal metaplasia (P < 0.05),but not with reflux symptomatic,endoscopic,or histological markers of GERD in CIM patients. SSBE was correlated with reflux symptomatic and endoscopic esophagitis (P < 0.01),but not with H. pylori infection and antral intestinal metaplasia. CONCLUSION:Dysplasia risk is significantly greater in SSBE patients than in CIM patients. CIM is a manifestation of H. pylori-associated and multifocal atrophic gastritis,whereas SSBE may result from GERD.

关键词： Endoscopy Barrett’s esophagus Cardia intestinal metaplasia Esophagogastric junction Gastroesophageal reflux disease

Effects of melatonin on learning abilities, cholinergic fibers and nitric oxide synthase expression in rat cerebral cortex

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Neural Regeneration Research 2006年第8期1卷 677-680页

作者： Bin Xu1, Junpao Chen2. Hailing Zhao3 1department of Neurology, the 187 Hospital of Chinese PLA, Haikou 571159, Hainan Province, china 2.0} of Neurology, Zhujiang Hospital, Southern Medical university, Guangzhou 5102.2. Guangdong Province, china 3Outpatient department, Haikou Hospital of Traditional Chinese Medicine, Haikou 570003, Hainan Province, china department of Neurology The 187 Hospital of Chinese PLA Haikou 571159 Hainan Province China department of Neurology Zhujiang Hospital Southern Medical University Guangzhou 510282 Guandong Province China Outpatient department Haikou Hospital of Tradiational Chinese Medicine Haikou 570003 Hainan Province China

BACKGROUND: Melatonin is a kind of hormones derived from pineal gland. Recent researches demonstrate that melatonin is characterized by anti-oxidation, anti-senility and destroying free radicals. While, effect and pathogenesis of pineal gland on learning ability should be further studied. OBJECTIVE: To investigate the effects of pinealectomy on learning abiliy, distribution of cholinesterase and expression of neuronal nitric oxide synthase (nNOS) in cerebral cortex of rats and probe into the effect of melatonin on learning ability, central cholinergic system and nNOS expression. DESIGN: Randomized grouping design and animal study. SETTING: department of Neurology, the 187 Hospital of Chinese PLA. MATERIALS: A total of 12.male SD rats, of normal learning ability testing with Y-tape maze, of clean grade, weighing 190-2.0 g, aged 6 weeks, were selected in this study. METHODS: The experiment was carried out in the department of Neurology, Zhujiang Hospital from July 1997 to June 2.00. All SD rats were divided into experimental group (n =6, pinealectomy) and control group (n =6, sham operation). Seven days later, rats in both two groups were continuously fed for 33 days. ① Learning ability test: The learning ability of rats was tested by trisection Y-type maze and figured as attempting times. ② Expression of acetylcholinesterase (AchE) was detected by enzyme histochemistry and nNOS was measured by SABC method. ③ Quantitative analysis of AchE fibers: AchE fibers density in unit area (surface density) was surveyed with Leica Diaplan microscope and Leica Quantimet 500+ image analytic apparatus and quantitative parameter was set up for AchE fibers covering density (μm2. per 374 693.656 μm2. moreover, the AchE fibers density was measured in Ⅱ-Ⅳ layers of motor and somatosensory cortex (showing three layers per field of vision at one time), in radiative, lacunaria and molecular layers of CA1, CA2.and CA3 areas, and in lamina multiforms of dentate gyrus. Three tissue slices wer

关键词： Effects of melatonin on learning abilities cholinergic fibers and nitric oxide synthase expression in rat cerebral cortex nNOS

An analytical model for SMAC protocol in multi-hop wireless sensor networks

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Science china(Information Sciences) 2010年第11期53卷 2323-2331页

作者： LUO Jun, JIANG LingGe& HE Chen department of Electronic Engineering, Shanghai Jiaotong university, Shanghai 2.02.0,{2. 1. department of Electronic Engineering Shanghai Jiaotong University Shanghai 200240 China

Considering the active/sleep dynamics and the contention backoscheme of SMAC protocol in multi-hop wireless sensor networks (WSNs), we model each node as a finite single server queue with server shutdown, and model each node’s states as a two-dimensional continuous-time Markov chain. Based on the model, we derive the network performance in terms of average packet loss ratio, network throughput, average packet delay and average power consumption. Experiment comparisons show that the analytical results match well with the simulation results, which validates the accuracy of the analytical model. Furthermore, using the analytical model can enable us to investigate the performance tradeobetween energy efficiency and QoS requirement, and give us theoretical insight into the optimal parameters such as duty cycle, mean active period and buffer size in multi-hop wireless sensor networks.

关键词： multi-hop wireless sensor networks Markov chain energy efficiency QoS

服务台数可变的 GI/G/n 排队系统的性能分析

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清华大学学报（自然科学版） 1998年第6期38卷 12-15页

作者：黄红选冯允成清华大学应用数学系北京航空航天大学管理学院

从离散事件系统的一条仿真样本路径出发，同时估计系统的性能以及系统参数改变时性能的变化量，是提高仿真效率的有效途径。对ＧＩ／Ｇ／ｎ排队系统，提出了一种估计服务台数ｎ对系统性能影响的新方法，在估计系统中顾客期望等待时间的... 详细信息

从离散事件系统的一条仿真样本路径出发，同时估计系统的性能以及系统参数改变时性能的变化量，是提高仿真效率的有效途径。对ＧＩ／Ｇ／ｎ排队系统，提出了一种估计服务台数ｎ对系统性能影响的新方法，在估计系统中顾客期望等待时间的同时，估计服务台数ｎ变为ｎ＋１时期望等待时间的变化量，从而可以间接地获得ＧＩ／Ｇ／ｎ＋１系统中顾客期望等待时间的估计值。数值实验表明，新方法在性能分析方面的效果良好。

关键词：排队系统摄动分析样本路径服务台数