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Antioxidant activity of methanol extracts of different parts of Lantana camara

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Asian Pacific Journal of Tropical Biomedicine 2012年第12期2卷 960-965页

作者： Badakhshan Mahdi-Pour Subramanion L Jothy Lachimanan Yoga Latha yeng chen Sreenivasan Sasidharan Department of Biotechnology Faculty of Applied SciencesAIMST University Institute for Research in Molecular Medicine(INFORMM) Universiti Sains Malaysia11800Pulau PinangMalaysia Dental Research & Training Unit and Oral Cancer Research and Coordinating Centre(OCRCC)Faculty of DentistryUniversity of Malaya

Objective:To investigate the antioxidant activity of methanolic extracts of Lantana camara(***)various parts and the determination of their total phenolics ***:The extract was screened for possible antioxidant activities by free radicaI scavenging activity(DPPH),xanthine oxidase inhibition activity and Griess—llosvay method。Results:The results showed that all the plant parts possessed antioxidant properties including radical scavenging,xanthine oxidase ildfibition and nitrites seavenging *** antioxidative activities were correlated with the total *** leaves extract of *** was more effective than that of other ***:This study suggests that *** extracts exhibit great potential for antioxidant activity and may be useful for their nutdtional and medicinal functions.

关键词： Lantana camara Cytotoxicity Oral acute toxicity Vero cell Plant extract

25t/h循环流化床锅炉与复合相变换热器配套使用的技术总结

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动力工程 2000年第5期20卷 839-841页

作者：林杰余平张志宇陈应明孔详谦晋江凤竹针织漂染实业有限公司泉州362000 九江科洋热技术设备有限公司九江332000 江西动力设备工程集团南昌330001 上海交通大学能源系上海200240

复合相变换热器在用作大幅度降低锅炉排烟温度的同时 ,又能使尾部受热面壁温保持较高温度 ,是一种彻底消除因受热面结露而造成低温腐蚀的高效节能设备。江西锅炉厂生产的 JG2 5 -3.82 / 45 0 -W 型锅炉是第一台采用复合相变换热空气预... 详细信息

复合相变换热器在用作大幅度降低锅炉排烟温度的同时 ,又能使尾部受热面壁温保持较高温度 ,是一种彻底消除因受热面结露而造成低温腐蚀的高效节能设备。江西锅炉厂生产的 JG2 5 -3.82 / 45 0 -W 型锅炉是第一台采用复合相变换热空气预热器循环流化床锅炉 ,已在福建凤竹集团有限公司运行。在运行中 ,锅炉的热工技术性能良好。表

关键词：循环流化床锅炉复合相变换热器低声频除灰器

如何描述山地景观的复杂性:英国国家公园景观特征评估案例比较

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风景园林 2024年第1期31卷 39-55页

作者： [马来西亚]陈巧遴李正北京林业大学园林学院

【目的】景观特征描述旨在对具有相似要素组合模式的区域进行分类和描述,将无限的景观复杂性简化为易于管理的空间单元。现有文献倾向于探索适用于所有景观的概念和框架,重点关注如何提高过程的透明度,并将历史复杂性纳入通用的技术路线... 详细信息

【目的】景观特征描述旨在对具有相似要素组合模式的区域进行分类和描述,将无限的景观复杂性简化为易于管理的空间单元。现有文献倾向于探索适用于所有景观的概念和框架,重点关注如何提高过程的透明度,并将历史复杂性纳入通用的技术路线中,但尚未根据不同的地貌类型进行针对性研究。阐明山地景观特征的描述是否有别于低地景观特征,并找出解释山地文化景观复杂性的方法,有助于加深对山地文化景观中自然和文化元素之间复杂关系的理解,可为今后的管理提供更有针对性的方法。【方法】重点收集15个国家公园的景观特征描述相关文件,包括20份景观特征评估(landscape character assessment,LCA)、10份历史景观特征识别(historic landscape characterisation,HLC)和2份历史土地利用评估(historic land-use assessment,HLA)。对于LCA文件,采用内容分析法,基于NVivo软件对重复出现的类型及其频率进行分类统计。编码综合采用自上而下、自下而上2种方法。参考相关的HLC和HLA文件分析LCA文件中对历史复杂性的处理,但由于英国在此方面缺乏统一的评估方法而没有进行编码。【结果】在景观变化方面,共识别出41个相关因子,并将它们划分为自然影响、文化影响和变化驱动力三大类;共识别出21个与制图属性相关的因子,并将它们划分为自然属性、文化属性、感知与审美属性三大类。景观特征类型的复合名称被分解成一系列单词,这些单词可归纳为24个因子,涉及自然特征、文化特征、感知与审美特征三大类。在历史复杂性处理方面,虽然所有英国国家公园LCA都按照历史分期描述了景观变化,但主要以自然属性、现状土地利用和实地形态作为景观特征分类的标准,在景观特征类型的命名中很少包含时间信息。只有个别LCA将历史信息纳入景观特征分类,如威尔士LCA。为了弥补LCA过度简化时间深度的缺点,英格兰和苏格兰的许多国家公园在考古学家和历史学家的主导下创建了单独的HLC或HLA。研究结果揭示了山地和低地国家公园之间的差异,发现不同国家公园对历史复杂性的处理方法主要受所在行政区域的影响,而非公园类型。尽管山地和低地的LCA可能会使用类似的研究框架和技术路线,但自然地形条件会对LCA产生重大影响。【结论】加深了人们对英国国家公园评估模式的理解,同时也为全球山地国家公园的文化LCA提供了启示,可为未来全面理解英国国家公园景观特征评估模式奠定基础,也为具有山地景观的类似地区提供指引。

关键词：文化景观特征描述山地复杂性国家公园

TCP-friendly source adaptation for multimedia applications over the Internet

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第Z1期7卷 1-6页

作者： SOH yeng-chai Centre for Modeling and Control of Complex System Nanyang Technological University Singapore

In this paper, we propose a simply TCP-friendly source adaptation framework to provide a proportional bandwidth sharing service. Our scheme is based on the framework of Monotonic Response Function (MRF), can be used to bound the sending rate of a source within a predefined interval and provide very smooth traffic, and is suitable for multimedia applications over the Internet. As our scheme is also very simple and TCP-friendly, it is easy to be deployed over the current Internet. We verify our scheme with experimental studies.

关键词： Source adaptation, TCP-friendly, TCP-compatible, Multimedia-friendly

Intermittent slipping of landslide regulated by dilatancy evolution and velocity-weakening friction law: an efficient numerical scheme

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Journal of Mountain Science 2016年第8期13卷 1333-1344页

作者： JAN Chyan-deng YANG Ray-yeng HWUNG Hwung-hweng chen Wen-yau Department of Hydraulic & Ocean Engineering National Cheng Kung University International Wave Dynamics Research Center National Cheng Kung University

When a block of dense sandy soil moves downhill, the shear-induced soil dilatancy along the basal shear boundary produces a negative value of excess pore pressure that increases the basal frictional resistance. Dilatancy angle,Ψ, the degree to which the basal soil dilates due to the shear, normally evolves during slope failure. A study by other researchers shows that if Ψ is constant, the block of dense soil will remain stable(or unstable) sliding when the velocity-weakening rate of the basal friction coefficient of the block is small(or large) enough. Moreover, during unstable sliding processes, the block of dense soil exhibits "periodic" patterns of intermittent slipping. Here, we used a more efficient and accurate numerical scheme to revisit that study. We expanded their model by assuming Ψ evolves during slope failure. Consequently, we acquired completely different results. For instance, even though the velocity-weakening rate of the friction coefficient is fixed at the same smaller(or larger) value that those researchers use, the stable(or unstable) steady states of landslide they predict will inversely change to unstable(or stable) when Ψ decreases(or increases) with the increase of slide displacement to a value small(or large) enough. Particularly, in unstable processes, the soil block exhibits "aperiodic" styles of intermittent slipping, instead of "periodic". We found out that the stick states appearing later last longer(or shorter) in the case of decreasing(or increasing) Ψ. Moreover, because the basic states of landslides with impacts of dilatancy evolution are not steady nor periodic, traditional stability-analysis methods cannot be "directly" used to analyze the stability of such landslides. Here, we broke through this technical problem to a degree. We showed that combining a concept called "quasi-steady-state approximation" with a traditional stability-analysis technique can qualitatively predict the instability onset of the landslides. Through this st

关键词： Landslide Stability analysis Intermittent slipping Dilatancy angle

放射性核素在海水、底质及海洋生物间的转移——Ⅰ.核素进入海水后的初始状态

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环境科学学报 1985年第2期 195-200页

作者：蔡福龙陈英许丕安邱曼华赖招才林荣盛国家海洋局第三海洋研究所国家海洋局第三海洋研究所

作者在建立的人工小生境中,研究了具有生态学意义的137Cs、134Cs、65Zn、60Co、59Fe、54Mn等核素在海水、底质及海洋生物间的转移规律.本文是该项研究的第一部分,研究悬浮物、底质对核素的富集和吸附,考察了核素进入海水后的初始状态.

关键词：小生境生态学意义转移规律初始状态富集系数 suspension 吸附值 Adsorption 湿重碎屑食物链

Targeting the cell cycle in esophageal adenocarcinoma:An adjunct to anticancer treatment

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World Journal of Gastroenterology 2011年第16期17卷 2063-2069页

作者： Martyn Dibb yeng S Ang Department of Gastroenterology Royal Albert Edward Infirmary School of Translational Medicine Faculty of Medical and Human SciencesThe University of Manchester

Esophageal adenocarcinoma is a major cause of cancer death in men in the developed *** poor outcomes with conventional therapies that predominantly target apoptosis pathways have lead to increasing interest in treatments that target the cell cycle.A large international effort has led to the development of a large number of inhibitors,which target cell cycle kinases,including cyclin-dependent kinases,Aurora kinases and polo-like *** phase Ⅰ/Ⅱ trials in solid tumors have often demonstrated only modest clinical benefits of *** may relate in part to a failure to identify the patient populations that will gain the most clinical *** compounds lacking the side effect profile of first-generation compounds may show utility as adjunctive treatments targeted to an individual's predicted response to treatment.

关键词： Esophageal adenocarcinoma Cell cycle Cyclin-dependent kinase Aurora kinases Polo-like kinase

Risk factors for neoplastic progression in Barrett's esophagus

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World Journal of Gastroenterology 2011年第32期17卷 3672-3683页

作者： Elizabeth F Wiseman yeng S Ang Department of Gastroenterology Royal Albert Edward Infirmary Wigan Lane Wigan Greater Manchester WN1 2NN United Kingdom Faculty of Medical and Human Sciences School of Translational Medicine The University of Manchester Oxford Road Manchester M13 9PL United Kingdom

Barrett's esophagus (BE) confers a significant increased risk for development of esophageal adenocarcinoma (EAC), with the pathogenesis appearing to progress through a "metaplasia-dysplasia-carcinoma" (MDC) sequence. Many of the genetic insults driving this MDC sequence have recently been characterized, providing targets for candidate biomarkers with potential clinical utility to stratify risk in individual patients. Many clinical risk factors have been investigated, and associations with a variety of genetic, specific gastrointestinal and other modifiable factors have been proposed in the literature. This review summarizes the current understanding of the mechanisms involved in neoplastic progression of BE to EAC and critically appraises the relative roles and contributions of these putative risk factors from the published evidence currently available.

关键词： Barrett’s esophagus Esophageal adeno-carcinoma Metaplasia-dysplasia-carcinoma Neoplastic progression Risk factors

放射性核素在海水、底质及海洋生物间的转移——Ⅱ.生物过程的作用

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环境科学学报 1985年第3期 335-340页

作者：蔡福龙陈英许丕安邱曼华赖招才林荣盛国家海洋局第三海洋研究所

本实验把扁藻、三角褐指藻、文蛤、毛蚶、对虾、罗非鱼等海洋生物引入人工水池小生境后,研究137Cs、134Cs、65Zn、60Co、59Fe、54Mn等核素在这一体系中行为的变化.结果表明,引入扁藻.三角褐指藻后,首先改变了54Mn的存在状态,使其不易富... 详细信息

本实验把扁藻、三角褐指藻、文蛤、毛蚶、对虾、罗非鱼等海洋生物引入人工水池小生境后,研究137Cs、134Cs、65Zn、60Co、59Fe、54Mn等核素在这一体系中行为的变化.结果表明,引入扁藻.三角褐指藻后,首先改变了54Mn的存在状态,使其不易富集在藻体上;引入实验动物一个月后,并没有减少原先浮游藻类、底质对核素的吸附,但水体中相当部分的54Mn、60Co已转移至动物体中,池底粪粒沉淀物中的54Mn、65Zn、60Co、59Fe的含量也相当高,从而大大改变了核素在人工水池小生境中的转移规律.

关键词：底质罗非鱼毛蚶浮游藻类 Fe Mn 非洲鲫鱼放射性同位素放射性核素富集系数富集量海水水生生物海洋生物生物过程