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关键词： Al thin-film line   Current stressing   Atomic flux divergence   Electromigration   Local thermal dissipation  

摘要： To improve the reliability of Al thin-film lines in integrated circuits, the influence of local thermal dissipation on electromigration (EM) was investigated. By performing current stressing experiments on Al thin-film lines with a special design, the unique distribution of hillocks/voids around four representative zones was found. The underlying mechanism was explained by investigating the corresponding atomic flux divergence according to finite element analyses. Such unique distribution of hillocks/voids, differing from the general EM phenomenon with hillocks at anode and voids at cathode, indicates the influence of local thermal dissipation induced by the voltage-measuring pads. Moreover, by changing the position of the voltage-measuring pads in the Al thin-film line, it was found that when the position of local thermal dissipation is farther from the center of the line, the EM resistance is higher. This finding provides a valuable insight for improving the EM resistance of Al thin-film lines and therefore enhancing the reliability of the corresponding devices. (C) 2016 Elsevier Ltd. All rights reserved.

关键词： Nitric oxide donors   Ovarian cancer cells   Cisplatin   Chemoresistance  

摘要： Ovarian cancer chemoresistance, both intrinsic and acquired, is the main obstacle in improving the outcome of anticancer therapies. Therefore the development of new treatment strategies, including the use of new compounds that can support the standard therapeutics is required. Among many candidates, nitric oxide (NO) donors, agents with multivalent targeted activities in cancer cells, are worth considering. The aim of this study was evaluation of SPER/NO and DETA/NO ability to enhance cisplatin cytotoxicity against different ovarian cancer cell lines. Obtained data indicate that NO donors action varies between different cancer cell lines and is strongest in low aggressive and cisplatin sensitive cells. While statistically significant, the enhancement of cisplatin cytotoxicity by NO donors is of low magnitude. The rise in the percentage of late apoptotic/necrotic ovarian cancer cells may suggest that NO donors enhancement action might be based on the cellular ATP depletion. Nevertheless, no significant impact of the NO donors, cisplatin or their combination on the expressions of ABCB1, BIRC5 and PTEN genes has been found. Although our data puts the therapeutical potential of NO donors to aid cisplatin action in question it may also point out at the further approach to utilize these compounds in therapies. (C) 2016 Elsevier B.V. All rights reserved.

关键词： Electromagnetic transient analysis   Ground-return   Transmission line parameters   Frequency dependent  

摘要： Electromagnetic transient processes are strongly related to the parameters of transmission lines. With the ground return parameters considered, the frequency dependent parameters of transmission lines are highly dependent on the soil parameters, which include resistivity and dielectric permittivity. In this paper, with the measurement results of frequency variation of soil parameters, the influence of the frequency dependent soil parameters on the frequency dependent characteristics of the transmission line parameters were studied using the complex return plane method. According to the calculation results, the frequency characteristics of soil parameters have obvious influences on the parameters of overhead transmission lines. The influences of the humidity, temperature and particle size of the soil on the ground return parameters were also evaluated. (C) 2015 Elsevier B.V. All rights reserved.

关键词： Malabaricone-A   MAPK signaling   PI3K/AKT signaling   Pro-oxidant   Reactive oxygen species  

摘要： Intrinsically cancer cells have higher basal levels of reactive oxygen species (ROS), which when augmented by pro-oxidants such as Malabaricone-A (MAL-A) triggers apoptotic cell death, secondary to 'turning on' of the apoptosis related cell signaling pathways. The effects of MAL-A upon key inflammation related signaling molecules were evaluated by western blotting in U937, a histiocytic lymphoma derived cell line. The impact of inhibitors of the pro-apoptotic MAPK and anti-apoptotic PI3K/AKT signaling pathways upon MAL-A induced cytotoxicity and generation of ROS was evaluated by a cell viability assay and flow cytometry respectively in two hematopoietic cell lines, U937 and MOLT3. MAL-A enhanced phosphorylation of the components of the pro-apoptotic pathway, namely ASK1, p38 and JNK. Alongside, MAL-A decreased the phosphorylation of AKT and mTOR. The cytotoxicity of MAL-A was attenuated by inhibitors of p38 and JNK, whereas its cytotoxic potential was enhanced in the presence of a PI3K/AKT inhibitor. Similarly, MAL-A mediated generation of ROS was decreased by inhibitors of p38MAPK and JNK, whereas the PI3K/AKT inhibitor potentiated its generation of ROS. Taken together, MAL-A mediated its cytotoxicity by enhanced generation of ROS via modulation of the apoptosis related cellular signaling pathways and tilting the balance towards a pro-apoptotic scenario. This was achieved via an up-regulation of MAPK (p38 and JNK) along with down-regulation of the PI3K/AKT/mTOR pathway indicating that manipulation of these pathways by compounds such as MAL-A are promising therapeutic targets, worthy of future pharmacological consideration. (C) 2016 Elsevier B.V. All rights reserved.

关键词： tomato (Solanum lycopersicum)   QTL analysis   flavonoids   alkaloids   introgression lines  

摘要： Semi-polar metabolites such as flavonoids, phenolic acids, and alkaloids are very important health-related compounds in tomato. As a first step to identify genes responsible for the synthesis of semi-polar metabolites, quantitative trait loci (QTLs) that influence the semi-polar metabolite content in red-ripe tomato fruit were identified, by characterizing fruits of a population of introgression lines (ILs) derived from a cross between the cultivated tomato Solanurn lycopersicum and the wild species Solanurn chmielewskii. By analyzing fruits of plants grown at two different locations, we were able to identify robust metabolite QTLs for changes in phenylpropanoid glycoconjugation on chromosome 9, for accumulation of flavonol glycosides on chromosome 5, and for alkaloids on chromosome 7. To further characterize the QTLs we used a combination of genome sequencing, transcriptomics and targeted metabolomics to identify candidate key genes underlying the observed metabolic variation.

关键词： Marsh   Geographically-weighted regression   Cokriging   Indicator kriging   False positives  

摘要： Stranded oil covering soil and plant stems in fragile Louisiana marshes was one of the most visible impacts of the 2010 Deepwater Horizon (DWH) oil spill. As part of the assessment of marsh injury after the DWH spill, plant stem oiling was broken into five categories (0%, 0-10%, 10-50%, 50-90%, 90-100%) and used as the independent variable for estimating death of vegetation, accelerated erosion, and other metrics of injury. The length of shoreline falling into each of these stem oiling categories was therefore a key measure of the total extent of marsh injury, and its accurate estimation is the focus of this paper. First, we used geographically-weighted logistic regression (GWR) to explore and model spatially varying relationships between stem oiling field data and secondary information (oiling exposure category) collected during shoreline surveys. We then combined GWR probability estimates with field data using indicator cokriging to predict the probability of exceeding four stem oiling thresholds (0,10, 50, and 90%) at 50 m intervals along the Louisiana shoreline. Cross-validation using Receiver Operating Characteristic (ROC) Curves demonstrate the greater prediction accuracy of the multivariate geostatistical approach relative to either aspatial regression or indicator kriging that ignores secondary information. (C) 2016 Published by Elsevier Ltd.

关键词： 六自由度串联机器人   末端运动线速度规划   扩展线位移法   矢量合角速度  

摘要： 将用于数控机床的扩展线位移方法引入到六自由度串联机器人末端运动线速度规划算法中,以提高机器人末端运动线速度控制效率。该算法借鉴数控机床中将刀具实际运动线速度与编程指定速度相互关联的扩展线位移方法思想,将机器人末端运动线速度转换为机器人运动矢量合角速度最终实现机器人末端运动线速度规划。通过搭建的机器人实验平台进行实验,实验结果表明提出的扩展线位移方法在机器人末端沿直线轨迹和圆弧轨迹运动时的实际合角速度与理论推算合角速度基本一致,实际关节角速度与理论关节角速度趋于一致。表明该方法能够有效实现机器人末端线速度轨迹规划。

关键词： 轨道交通   深圳   城市空间  

摘要： 以笔者参与的深圳市轨道交通13号线工程可行性研究、勘察设计总承包投标方案为例,结合城市交通对城市空间发展影响的相关理论,通过梳理深圳市轨道交通13线在宏观、中观、微观三个层次上对城市空间的影响,初步探讨了轨道交通建设对城市不同层次、不同区域的作用模式并总结归纳。为今后的轨道交通建设对城市空间发展影响的研究提供借鉴和参考。