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物理学报 2004年第9期53卷 3025-3032页

作者：郭旗许超彬华南师范大学信息光电子科技学院传输光学实验室广州510631

从 1 +1维强非局域模型出发 ,讨论了偏离束腰入射的高斯光束在非局域非线性介质中的传输特性 ,得到了精确的解析解 .结果表明 ,在聚焦介质中偏离束腰入射时 ,不论入射功率多大 ,光束束宽将发生周期性波动 ,光孤子不复存在 ,这与从高斯... 详细信息

从 1 +1维强非局域模型出发 ,讨论了偏离束腰入射的高斯光束在非局域非线性介质中的传输特性 ,得到了精确的解析解 .结果表明 ,在聚焦介质中偏离束腰入射时 ,不论入射功率多大 ,光束束宽将发生周期性波动 ,光孤子不复存在 ,这与从高斯光束束腰入射的情况有本质的不同 ;入射功率决定了光束平均束宽的大小 ,入射位置决定了光束初始的演化趋势 .比较了在入射位置相同的条件下 ,聚焦介质、散焦介质和线性均匀介质中光束的演化 .给出了“空间啁啾”的定义 ,偏离束腰入射的物理本质是光束的不同入射位置对应不同的初始空间啁啾 .空间啁啾的概念。

关键词：非局域非线性介质空间光孤子高斯光束聚焦介质散焦介质

Discounted Optimality for Continuous-Time Markov Decision Processes in Polish Spaces

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Discounted Optimality for Continuous-Time Markov Decision Pr...

Preparation and Performance of Geopolymers

第25届中国控制会议

作者： guo Xianping The school of Mathematics and Computational Science Zhongshan University, guangzhou 510275

＜正＞This paper deals with continuous-time Markov decision processes in Polish spaces, under a discounted expected reward criterion. We first give conditions under which we ensure the existence of optimal stationary policies by using the technique of extended infinitesimal operators, and also provide a recursive way to compute （or at least to approximate） the optimal reward values. Finally, we use controlled Generalized Potlach processes to show that all conditions in this paper are satisfied, whereas the earlier conditions fail to hold, and then we further apply our results to the discounted optimal control problems of several population processes.

关键词： Continuous-time Markov decision processes general state space discounted rewards optimal stationary policy

来源： cnki会议评论

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Journal of Wuhan University of Technology(Materials Science) 2008年第3期23卷 326-330页

作者：郭文瑛 South China University of Technology Key Laboratory of Specially Functional Materials and Advanced Manufacturing Technology Ministry of EducationSouth China University of TechnologyGuangzhou 510640China

The influence of each factor on the reaction of geopolymers material was investigated by using the orthogonal experimental design method, which got the optimal condition of reaction. Based on this results the performances of geopolymers were investigated. The results are as follows：（1） The effect of each factor on the compressive strength of geopolymers was different; （2） For paste the optimal condition of reaction is that the modulus and the concentration of sodium silicate solution are 1.2 and 40%, the calcined temperature and calcined time of kaolin are 800 ℃ and 2 h, and the liquid-solid ratio is 1.25; （3） When the pH value of solution is higher than l, the compressive strength of Geopolymers will not decrease as that in the water; （4） As the calcined temperature of samples were lower than 700 ℃ the heat-resistant of geopolymers was good;（5） Geopolymers is unlikely to react with the active aggregate.

关键词： geopolymers cross experimental design method optimal condition performance

Effects of salvianolic acid B on proliferation, neurite outgrowth and differentiation of neural stem cells derived from the cerebral cortex of embryonic mice

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Science China(Life Sciences) 2010年第6期53卷 653-662页

作者： guo guoQing1,LI Bin1,WANG YuanYuan1,SHAN AiJing1,SHEN WeiZai1,YUAN Lin2 & ZHONG ShiZhen2 1Department of Anatomy,Medical College of Jinan University,guangzhou 510630,China 2Institute of Clinical Anatomy,Key Laboratory of Tissue Construction and Detection of Guangdong Province,Southern Medical University,guangzhou 510150,China 1. Department of Anatomy Medical College of Jinan University Guangzhou 510630 China2. Institute of Clinical Anatomy Key Laboratory of Tissue Construction and Detection of Guangdong Province Southern Medical University Guangzhou 510150 China

Salvianolic acid B is isolated from Salvia miltiorrhiza,the root of which is widely used as a traditional Chinese medicine to treat ***,little is known about how salvianolic acid B influences growth characteristics of neural stem cells (NSCs).The purpose of the present study was to evaluate the effects of salvianolic acid B on proliferation,neurite outgrowth and differentiation of NSCs derived from the cerebral cortex of embryonic mice using MTT,flow cytometry,immunofluorescence and *** was found that 20 μg mL·1 and 40 μg mL·1 salvianolic acid B had similar effects on proliferation of NSCs,and a suitable concentration of salvianolic acid B increased the number of NSCs and their derivative *** growth-promoting activity of salvianolic acid B was dependent on and associated with an accumulation in the G2/S-phase cell *** acid B also promoted the neurite outgrowth of NSCs and their differentiation into *** mRNA for tau,GFAP and nestin were present in differentiating neurospheres induced by salvianolic acid ***,high-level expression of tau mRNA and low-level expression of GFAP mRNA was detected in differentiated cells,in contrast to the control *** collective evidence indicates that exogenous salvianolic acid B is capable of promoting proliferation of neurospheres and differentiation towards the neuronal lineage in vitro and may act in the proliferation of NSCs and may promote NSC differentiation into neuronal cells.

关键词： salvianolic acid B proliferation differentiation neurite outgrowth neural stem cells cerebral cortex embryonic mouse

TiO_2-assisted photo-catalysis degradation process of dye chemicals

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Journal of Environmental Sciences 2001年第1期13卷 64-68页

作者： LI Fang\|bai 1,2 , GU guo\|bang\+2, HUANG guo\|feng\+1, GU Yun\|li\+2, WAN Hong\|fu\+1 (1.Guangdong Institute of Eco\|Environment and Soil Science,guangzhou 510650, China. E\|mail: fbli@*** 2.College of Chemical Engineering, South Technolog Guangdong Institute of Eco-Environment and Soil Science College of Chemical Engineering South China Technology University Guangzhou China. fbli@***

The photo-catalytic degradation pathway and degradation products of methylene blue, rhodamine B, methyl orange, and malachite green in aqueous TiO2 suspension irradiated by high pressure mercury lamp by means of UV-visible absorption spectra and ion chromatography were investigated. The photo-catalysis degradation of dye solutions with charges was greatly effected by pH value owing to the electrostatic model. The photo-degradation rate of dyes anion increased with the decrease of pH value, in contrast, the photo-degradation rate of dyes cation increased with the increase of pH value. And the absorption peaks diminished with a blue shift. After illuminated for 30 minutes, a part of dye chemicals were completely mineralized and transferred into inorganic species including chloride ion, ammonium ion, nitrate ion, sulfate ion. And the addition of 100 mmol/L H2O2 promoted the formation of inorganic species. In this study, the quantity of ammonium ion was much more than that of nitrate ion. That indicated the formation of nitrate is from ammonium. The purification rate of COD in four kinds of dye solution was 71.7%-88.7%. The decrease of COD of dyes solution implies the feasibility of the environmental application of photo-catalyzed process.

关键词： Chromatography Irradiation Mercury vapor lamps pH effects Photocatalysis Spectrum analysis Titanium oxides

One patient with metastastic colorectal cancer successfully treated by combination of targeted agents after failure of chemotherpay

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Chinese Journal of Cancer 2010年第12期29卷 1023-1028页

作者： Liang-Ping Xia1,2, Pei-Hong Wu1,3, Jian-Chuan Xia1,4, Bei Zhang1,2, Zhong-Zhen Guan1,5, De-Sen Wan1,6, Gui-Fang guo1,2, Yi-Xin Zeng1,7 1 State Key Laboratory of Oncology in South China, guangzhou, Guangdong 510060, P. R. China 2 VIP Region, Sun Yat-sen Universty Cancer Center, guangzhou, Guangdong 510060, P. R. China 3 Department of Medical Imaging and Interventional Radiology, Sun Yat-sen Universty Cancer Center, guangzhou, Guangdong 510060, P. R. China 4 Biotherapy Cancer, Sun Yat-sen Universty Cancer Center, guangzhou, Guangdong 510060, P. R. China 5 Department of Medical Oncology, Sun Yat-sen Universty Cancer Center, guangzhou, Guangdong 510060, P. R. China 6 Department of Colorectal Cancer,Sun Yat-sen Universty Cancer Center, guangzhou, Guangdong 510060, P. R. China 7 Sun Yat-sen Universty Cancer Center, guangzhou, Guangdong 510060, P. R. China VIP Region Sun Yat-sen Universty Cancer Center StateKey Laboratory of Oncology in South China Guangdong Guangzhou 510060 Department of Medical Imaging and Interventional Radiology Sun Yat-sen Universty Cancer Center StateKey Laboratory of Oncology in South China Guangdong Guangzhou 510060 Biotherapy Cancer Sun Yat-sen Universty Cancer Center StateKey Laboratory of Oncology in South China Guangdong Guangzhou 510060 Department of Medical Oncology Sun Yat-sen Universty Cancer Center StateKey Laboratory of Oncology in South China Guangdong Guangzhou 510060 Department of Colorectal Cancer Sun Yat-sen Universty Cancer Center StateKey Laboratory of Oncology in South China Guangdong Guangzhou 510060 Sun Yat-sen Universty Cancer Center StateKey Laboratory of Oncology in South China Guangdong Guangzhou 510060

Either cetuximab or bevacizumab can improve the survival of patients with metastastic colorectal cancer (mCRC) if administered combided with cytotoxic agents. However, the effect of two or more target agents in combination is uncertain in these patients. Here, we reported a patient with mCRC successfully treated by a combination of target agents after the failure of chemotherapy. The patient received palliative resection of primary tumor followed by 9 cycles of postoperative XELOX regimen, cytokine-induced killer cell (CIK)-based biotherapy, traditional Chinese medicine, particle implantation in the lung metastatic lesions. The tumor progressed 20 months after the standard treatments. Then, the regimen cetuximab, bevacizumab and cefitinib was applied. During the treatment with targeted agents, grade IV acne-like rash and relatively severe parionychia of the toes occurred. Both of them recovered smoothly. The PET-CT reexamination at 40 days after the target treatment showed that the metabolism of mediastinal lymph nodes basically recovered to a normal level. The combination of multiple targeted agents obtained a progression-free survival(PFS) of 11 months and the patient with a good quality of life during this period.

关键词：药物治疗结直肠癌转移性患者大肠细胞毒性靶向药物不确定性

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新制度经济学视野下的教师管理变革

教育发展研究 2009年第2期29卷 36-41页

作者：郭凯广东教育学院教育系副主任副教授广州510303

从新制度经济学的视角考察,我国教师管理制度设计存在着诸多问题,主要表现为:重教师"道德人"假设而轻教师"经济人"假设;重视教师管理的正式制度而忽视非正式制度;重视教师管理制度的约束功能而忽视激励功能;重视政府、学校对教师的管理... 详细信息

从新制度经济学的视角考察,我国教师管理制度设计存在着诸多问题,主要表现为:重教师"道德人"假设而轻教师"经济人"假设;重视教师管理的正式制度而忽视非正式制度;重视教师管理制度的约束功能而忽视激励功能;重视政府、学校对教师的管理而忽视家长的参与等。基于对以上问题的分析,本文指出教师管理变革的方向应包括:承认教师自利行为的正当性;充分利用教师管理的非正式制度;强化教师管理制度的激励功能;扩大家长参与教师管理的权力等。

关键词：新制度经济学教师管理激励机制教育发展

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中小学校长权力的性质与边界

教育发展研究 2008年第20期28卷 41-46页

作者：郭凯广东教育学院教育系副教授广州510303

中小学校长权力不同于校长职责、学校权利和校长权利,它是一种公共权力、委托权力、制度权力和职位权力,这一性质是确定校长权力边界的主要依据。同时,对校长权力边界的确定应遵循以下基本原则:校长权力应有助于实现教育公共性;校长权... 详细信息

中小学校长权力不同于校长职责、学校权利和校长权利,它是一种公共权力、委托权力、制度权力和职位权力,这一性质是确定校长权力边界的主要依据。同时,对校长权力边界的确定应遵循以下基本原则:校长权力应有助于实现教育公共性;校长权力应受到"监督"而不是"限制";校长权力应与校长责任一致;校长权力应与国家政治体制、管理体制及文化传统相适应。

关键词：校长权力公共权力委托权力制度权力职位权力

A Markov-switching predator-prey model with Allee effect for preys

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International Journal of Biomathematics 2020年第3期13卷 79-106页

作者： Xiaoxia guo Zhiming guo School of Mathematics and Information Sciences guangzhou University Guangzhou 510006P.R.China Department of Mathematics and Statistics Concordia University Montreal-H3G2W1Canada

This paper concerns with a Markov-switching predator-prey model with Allee effect for *** conditions under which extinction of predator and prey populations occur have been *** conditions are also given for persistence and global attractivity in *** addition,stability in the distribution of the system under con-sideration is derived under some ***,numerical simulations are carried out to illustrate theoretical results.

关键词： Markov-switching prey-predator model Allee effect extinction persistence in mean stable in distribution