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Cucurbitacin B suppresses metastasis mediated by reactive oxygen species(ROS) via focal adhesion kinase(FAK) in breast cancer MDA-MB-231 cells

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Chinese Journal of Natural Medicines 2018年第1期16卷 10-19页

作者： luo wei-wei ZHAO Wen-Wen LU Jin-Jian WANG Yi-Tao CHEN Xiu-Ping State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical Science University of Macao

Metastasis is responsible for the majority of cancer-related deaths and prevention of metastasis remains a big challenge for cancer therapy. Cucurbitacin B(Cuc B) is a natural triterpenoid with potent anticancer activities while its effect on metastasis remains unclear. In the present study, the inhibitory effect and mechanisms of Cuc B on metastasis were investigated in MDA-MB-231 breast cancer cells. The cells were treated with or without Cuc B, and the cytotoxicity was determined by MTT assay. The effect of Cuc B on metastasis was evaluated with wound healing, transwell, and adhesion assays. Furthermore, the adhesion of cancer cells to endothelial cells was determined. The protein expression was determined by Western blotting. Cuc B(< 100 nmol·L~^(-1)) showed no obvious cytotoxicity to MDA-MB-231 cells, but significantly inhibited migration, invasion, and adhesion to Matrigel, fibronectin, type I collagen, and endothelial cells. Cuc B dramatically inhibited the phosphorylation of focal adhesion kinase(FAK) and paxillin in dose-and time-dependent manners. Furthermore, Cuc B induced intracellular reactive oxygen species(ROS) generation, which could be reduced by N-acetyl-l-cysteine(NAC). In addition, NAC pretreatment could reverse Cuc B-induced suppression of migration and adhesion, expression of FAK, but showed no effect on paxillin expression. In summary, Cuc B suppressed ROS-dependent metastasis through FAK pathway in breast cancer MDA-MB-231 cells, demonstrating novel mechanisms for the anticancer effects of Cuc B.

关键词： Cucurbitacin B Metastasis ROS FAK Breast Cancer

Changes of Cu, Zn, and Cd speciation in sewage sludge during composting

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Journal of Environmental Sciences 2005年第6期17卷 957-961页

作者： GAO Ding ZHENG Guo-di CHEN Tong-bin luo wei GAO wei ZHANG Yi-an LI Yan-xia Center for Environmental Remediation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

The potential toxicity risks from heavy metals depend on their chemical speciation. The four stages of the Tessier sequential extraction method were employed to investigate changes in heavy metal speciation （Cu, Zn, and Cd） of sewage sludge during forced aeration composting, and then to identify whether the composting process would reduce or enhance their toxicities. Throughout the composting process, the exchangeable, carbonate-bound, Fe-Mn oxide-bound, and organic matter-bound fractions of Cu were converted to the residual Cu fraction. The organic matter-bound Cu fraction greatly contributed to this transformation. Residual Zn fraction was transformed to the Fe-Mn oxide-bound and organic matter-bound fractions after composting. The residual Zn fraction was a major contributor to the organic matter-bound Zn fraction. The availability of Cu and Zn was reduced by composting such that the risk of heavy metal toxicity decreased with prolonged treatment times. Additionally, attention should be paid to the increased availability of Cd in sewage sludge after composting treatment.

关键词： composting distribution heavy metal sewage sludge speciation

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动叶具有缩放型流道的涡轮级效率特性分析

工程热物理学报 2014年第11期35卷 2168-2172页

作者：徐晓赵巍雒伟伟中国科学院工程热物理研究所北京100190 中国科学院大学北京100190 中国科学院轻型动力重点实验室北京100190

针对一动叶采用缩放式叶型设计、以无导叶对转涡轮为应用背景的涡轮级,通过数值模拟进行研究发现,在设计换算转速下,该涡轮级效率特性呈现"双峰僧'的特点。随着落压比增大,首先动叶进气攻角由负变为零,效率升高并达到极大值;其后,动叶... 详细信息

针对一动叶采用缩放式叶型设计、以无导叶对转涡轮为应用背景的涡轮级,通过数值模拟进行研究发现,在设计换算转速下,该涡轮级效率特性呈现"双峰僧'的特点。随着落压比增大,首先动叶进气攻角由负变为零,效率升高并达到极大值;其后,动叶流道内形成正激波,其自身产生波阻并在吸力面引起边界层分离,效率下降;随后,该激波向下游移至叶片尾缘,尾迹损失明显增加,加上波阻、边界层分离的综合作用,效率达到极小值;然后,该激波演变为尾缘斜激波,自身波阻减小,而且它在吸力面引起的边界层分离消失,流道内总体损失下降,效率又会上升并在设计点附近达到极大值;其后,该激波波前马赫数不断增大,波阻损失随之增加,同时尾迹损失也持续增加,效率又会下降。结果显示,高负荷跨音工况下激波与边界层干扰引起的边界层分离损失以及动叶高出口马赫数时尾缘区域的损失(包括波阻损失和尾迹损失)占总体损失的至少1/2以上,在设计优化过程中应重点关注与之相关的动叶吸力面扩张段和叶片尾缘区域。

关键词：缩放型叶栅流道无导叶对转涡轮效率特性数值模拟

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1+1对转涡轮变工况性能分析与优化设计

推进技术 2017年第7期38卷 1483-1490页

作者：常骐越赵巍雒伟伟唐菲中国科学院工程热物理研究所北京100190 中国科学院大学北京100190 中国科学院轻型动力重点实验室北京100190

为阐明1+1对转涡轮变工况性能损失的主要来源并提出改进方法,以1+1对转涡轮为例进行了部分载荷工况下的流场模拟、分析和优化。与相同设计参数的同转涡轮进行部分载荷工况流场对比,发现部分转速下同转涡轮在级间导叶吸力面前缘出现分离,... 详细信息

为阐明1+1对转涡轮变工况性能损失的主要来源并提出改进方法,以1+1对转涡轮为例进行了部分载荷工况下的流场模拟、分析和优化。与相同设计参数的同转涡轮进行部分载荷工况流场对比,发现部分转速下同转涡轮在级间导叶吸力面前缘出现分离,而1+1对转涡轮在压力面前缘出现分离。针对此流动损失,为1+1对转涡轮级间导叶提出了一种基于分离角的压力面优化设计方法,提高了近前缘压力面的气流速度,增强了其对负攻角的适应性,基本消除了叶片14%、58%和92%叶高处压力面前缘的流动分离,在正攻角工况下亦保持了良好气动性能。数值验证了该涡轮的效率在全工况范围内明显提高,而设计点效率未受负面影响。其中,在对转涡轮70%和50%设计转速的两个工况点上,低压涡轮效率较优化前分别提升了1.5%和2.0%,涡轮总效率较优化前分别提升了0.5%和0.7%。

关键词： 1+1对转涡轮变工况优化设计

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随机需求和产量下基于损失规避的零售商博弈

控制与决策 2017年第5期32卷 920-924页

作者：刘伟宋士吉乔颖罗伟伟军事经济学院基础部武汉430035 清华大学自动化系北京100084 湖北经济学院工商管理学院武汉430205

研究在需求和产量均为随机变量的情况下,带有损失规避偏好的零售商之间的博弈.当多个相同的零售商向同一供应商订购时,如果总需求按照每个零售商的订购量在总订购量中所占比例进行分配,则该博弈中存在唯一的对称性Nash均衡,且总均衡订... 详细信息

研究在需求和产量均为随机变量的情况下,带有损失规避偏好的零售商之间的博弈.当多个相同的零售商向同一供应商订购时,如果总需求按照每个零售商的订购量在总订购量中所占比例进行分配,则该博弈中存在唯一的对称性Nash均衡,且总均衡订购量关于损失规避水平递减,关于零售商数量递增.此外,如果损失规避水平(零售商数量)高于(低于)临界值,则竞争情况下供应链总库存水平比集中管理情况下的低.仿真实验验证了上述结果.

关键词：损失规避随机产量博弈库存

Boosting Oxygen Evolution Reaction Performance on NiFe‑Based Catalysts Through d‑Orbital Hybridization

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Nano-Micro Letters 2025年第1期17卷 281-292页

作者： Xing Wang wei Pi Sheng Hu Haifeng Bao Na Yao wei luo State Key Laboratory of New Textile Materials and Advanced Processing Technology Key Laboratory of New Textile Materials and Applications of Hubei ProvinceSchool of Materials Science and EngineeringWuhan Textile UniversityWuhan 430200People’s Republic of China College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072People’s Republic of China

Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based *** introducing a third metal into NiFe-based catalysts to construct asymmetrical M-NiFe units,the d-orbital and electronic structures can be adjusted,which is an important strategy to achieve sufficient oxygen evolution reaction(OER)performance in ***,the ternary NiFeM(M:La,Mo)catalysts featured with distinct M-NiFe units and varying d-orbitals are reported in this *** and theoretical calculation results reveal that the doping of La leads to optimized hybridization between d orbital in NiFeM and 2p in oxygen,resulting in enhanced adsorption strength of oxygen intermediates,and reduced rate-determining step energy barrier,which is responsible for the enhanced OER *** critically,the obtained NiFeLa catalyst only requires 1.58 V to reach 1 A cm^(−2) in an anion exchange membrane electrolyzer and demonstrates excellent long-term stability of up to 600 h.

关键词： NiFe-based catalysts d-orbital coupling Oxygen evolution reaction Anion exchange membrane electrolyzer

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矢量自对偶形态学滤波算子

自动化学报 2015年第5期41卷 1013-1023页

作者：雷涛樊养余罗维薇王履程兰州交通大学电子与信息工程学院兰州730070 西北工业大学电子信息学院西安710072

自对偶形态学算子不依赖形态学腐蚀、膨胀算子的先后次序,是一种等同处理图像背景和前景的形态学算子.而将自对偶形态学算子拓展到多通道图像处理是一个难题.为了解决该问题,提出了基于极值约束的矢量自对偶形态学滤波算子(EC-VSDMF).... 详细信息

自对偶形态学算子不依赖形态学腐蚀、膨胀算子的先后次序,是一种等同处理图像背景和前景的形态学算子.而将自对偶形态学算子拓展到多通道图像处理是一个难题.为了解决该问题,提出了基于极值约束的矢量自对偶形态学滤波算子(EC-VSDMF).首先根据对称矢量排序算法构建满足对偶性的矢量形态学算子,然后依据形态学算子中的极值原理优化矢量集合,从而有效抑制矢量集合中包含单通道极值的矢量作为输出结果,最终实现了具有约束功能的矢量自对偶形态学滤波算子(VSDMF).实验结果表明,EC-VSDMF继承了传统自对偶形态学滤波算子的性质,将其应用于彩色图像滤波可以改善现有矢量形态学滤波算子导致滤波后图像亮度和色度发生偏移的问题.滤波后的图像在有效抑制噪声的同时较好地保留了图像细节,滤波性能甚至超过了多种现有的矢量中值滤波算子.

关键词：数学形态学彩色图像滤波矢量排序自对偶形态学算子

聚合物-表面活性剂二元驱提高采收率机理实验

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石油勘探与开发 2017年第4期44卷 600-607页

作者：刘卫东罗莉涛廖广志左罗魏云云姜伟中国石油勘探开发研究院河北廊坊065007 中国科学院渗流流体力学研究所河北廊坊065007 清华大学环境学院北京100084 中国石油勘探与生产分公司北京100011 中国石化石油工程技术研究院北京100101

针对新疆油田七中区开发现状,设计聚合物-表面活性剂二元驱的填砂管、天然岩心及微观模型驱油实验,研究二元驱提高采收率机理,为油田现场提供二元驱优化配方。二元驱采收率增幅随着水油黏度比增大而增大,随着界面张力减小而增大。毛细... 详细信息

针对新疆油田七中区开发现状,设计聚合物-表面活性剂二元驱的填砂管、天然岩心及微观模型驱油实验,研究二元驱提高采收率机理,为油田现场提供二元驱优化配方。二元驱采收率增幅随着水油黏度比增大而增大,随着界面张力减小而增大。毛细管准数反映二元体系溶液黏度和界面张力的协同效应,应以其为准优化筛选最佳配方。新疆油田七中区二元驱溶液临界黏度比2.5、临界界面张力数量级为1′10-2 m N/m、临界毛细管准数数量级为1′10-3;优选出配方为0.3%KPS-1+1 115 mg/L HPAM,可提高采收率23.96%。二元驱通过聚合物增黏,降低驱替相流度,增加油相流度,使流度比减小,克服了注水指进,增加了吸水厚度,从而提高波及系数,进而启动盲端残余油;通过表面活性剂降低界面张力,降低黏附功,使残余油乳化、剥离、拉丝并易于启动,同时乳状液进一步增加驱替相黏度,在低界面张力和较高黏度下,毛细管准数大幅度提高,从而提高洗油效率,进而启动岛状、柱状及膜状残余油,最终提高了采收率。

关键词：聚合物表面活性剂二元驱提高采收率黏度比界面张力毛细管准数

Performance Evaluation of China's Agricultural Listed Companies Based on DEA Model

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Asian Agricultural Research 2012年第5期4卷 1-6,12页

作者： luo Hua-wei ,ZHANG wei School of Economics and Management,Sichuan Agricultural University,Chengdu 611130,China

In order to evaluate the performance of China's agricultural listed companies,we analyze the overall efficiency,pure technical efficiency and scale efficiency of China's agricultural listed companies on the basis of input-output data concerning 34 agricultural listed companies,using BCC model in data envelopment analysis ( DEA) model. Then we analyze input-output redundancy situation using the slack variable derived from the model. The results show that the overall efficiency of China's agricultural listed companies is good,and the gap in efficiency between sub-industries is small; there is significant difference in performance between listed companies engaged in the same sub-industry,and the reason for invalid DEA in companies within the industry is complex; total assets and asset-liability ratio are high,and the effective output is not fully realized. Finally corresponding recommendations are put forward for promoting the performance of agricultural listed companies as follows: strengthening brand awareness; promoting the level of production technology; adjusting the input structure; transforming the agricultural growth mode.

关键词： Performance evaluation DEA model Agricultural list