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排序方式: 共有321条查询结果,搜索用时 125 毫秒
1.
Md Saifur Rahman Md Badrul Alam Young Kyun Kim Mst Hur Madina Ismail Fliss Sang Han Lee Jin Cheol Yoo 《International journal of molecular sciences》2021,22(10)
In this study, we investigate the immunomodulatory effects of a novel antimicrobial peptide, YD1, isolated from Kimchi, in both in vitro and in vivo models. We establish that YD1 exerts its anti-inflammatory effects via up-regulation of the Nrf2 pathway, resulting in the production of HO-1, which suppresses activation of the NF-κB pathway, including the subsequent proinflammatory cytokines IL-1β, IL-6, and TNF-α. We also found that YD1 robustly suppresses nitric oxide (NO) and prostaglandin E2 (PGE2) production by down-regulating the expression of the upstream genes, iNOS and COX-2, acting as a strong antioxidant. Collectively, YD1 exhibits vigorous anti-inflammatory and antioxidant activity, presenting it as an interesting potential therapeutic agent. 相似文献
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本文首先从核心理念、实现机理上对批量过程控制标准ISA S88进行了全面地解读分析,成功地将S88标准转换成了一个具体的产品--UWinBatch,然后以果汁生产线为例,对UWinBatch的开发过程、丰富的功能模块进行了介绍,最后在某公司的农药生产线项目应用中,以实际效果证明了UWinBatch是一款高度符合S88标准,能给用户带来极大收益的优秀产品。 相似文献
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Adsorption and antibacterial effect of copper-exchanged montmorillonite on Escherichia coli K88 总被引:1,自引:0,他引:1
Calcium montmorillonite (Ca-MMT), sodium montmorillonite (Na-MMT) and acid-activated montmorillonite (AAM), and their Cu2+-exchanged montmorillonites (Cu-MMT), Cu*Ca-MMT, Cu*Na-MMT and Cu*AAM, were used to study the antibacterial activity on Escherichia coli K88. AAM, Na-MMT and Ca-MMT showed some ability to reduce bacterial plate counts by 37.4%, 13.4% and 14.2%, respectively. Exchanging the montmorillonite with Cu2+ enhanced the antibacterial activity. The Cu*AAM, Cu*Na-MMT and Cu*Ca-MMT reduced the bacterial plate counts by 98.6%, 97.5% and 95.6%. Attempts were made to study the desorption of Cu2+ by washing with sterile physiological saline solution for 24 h. The washing solutions did not show a significant reduction of the bacterial counts, while the washed Cu-MMT retained their full antibacterial activity. Results from time-depending studies showed that the reduction of the bacterial counts by Cu-MMT increased during 24 h. The ranking of antibacterial activity of the three Cu-MMT was as Cu*AAM > Cu*Na-MMT > Cu*Ca-MMT. E. coli thrived optimally in a pH range from 5 to 7. Beyond this range, the bacterial counts decreased as the pH reduced the viability of the bacteria. The ranking of antibacterial activity of Cu-MMT was not affected by pH. The mechanism by which bacterial counts are reduced may involve the enhanced affinity of Cu-MMT for E. coli K88 and the antibacterial activity of Cu2+. 相似文献
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本文以DSP芯片C6455为应用平台,介绍了一种自适应的光纤和网络接口通信设计方法。系统具有两个光纤和网络接口,可以自动识别所插入的设备,在不断电情况下可以任意交换接口,无须用户参与。文中详细介绍了该系统的软硬件设计方法。 相似文献
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基于ATmega88的USART多处理机通信 总被引:1,自引:0,他引:1
单片机接口技术发展的一个趋势是:由并行外围总线接口向串行外围总线接口转变。USART全称是通用同步异步收发器,它是一种单片机外设模块,该资源常用于CPU与较远距离的设备进行通讯。USART接口可以用作同步传送或异步传送,是工业通信中的一种标准接口,而且USART串行接口外围扩展技术具有方便灵活、电路系统简单、占用I/O口资源少等特点。文章所实现的USART多处理机通信,通过地址和数据两种命令格式进行交互,此通信系统可以用作设备控制总线,方便灵活地控制外围设备。 相似文献
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In an organization operating in the bancassurance sector we identified a low-risk IT subportfolio of 84 IT projects comprising together 16,500 function points, each project varying in size and duration, for which we were able to quantify its requirements volatility. This representative portfolio stems from a much larger portfolio of IT projects. We calculated the volatility from the function point countings that were available to us. These figures were aggregated into a requirements volatility benchmark. We found that maximum requirements volatility rates depend on size and duration, which refutes currently known industrial averages. For instance, a monthly growth rate of 5% is considered a critical failure factor, but in our low-risk portfolio we found more than 21% of successful projects with a volatility larger than 5%. We proposed a mathematical model taking size and duration into account that provides a maximum healthy volatility rate that is more in line with the reality of low-risk IT portfolios. Based on the model, we proposed a tolerance factor expressing the maximal volatility tolerance for a project or portfolio. For a low-risk portfolio its empirically found tolerance is apparently acceptable, and values exceeding this tolerance are used to trigger IT decision makers. We derived two volatility ratios from this model, the π-ratio and the ρ-ratio. These ratios express how close the volatility of a project has approached the danger zone when requirements volatility reaches a critical failure rate. The volatility data of a governmental IT portfolio were juxtaposed to our bancassurance benchmark, immediately exposing a problematic project, which was corroborated by its actual failure. When function points are less common, e.g. in the embedded industry, we used daily source code size measures and illustrated how to govern the volatility of a software product line of a hardware manufacturer. With the three real-world portfolios we illustrated that our results serve the purpose of an early warning system for projects that are bound to fail due to excessive volatility. Moreover, we developed essential requirements volatility metrics that belong on an IT governance dashboard and presented such a volatility dashboard. 相似文献
9.
Marco Riani 《Computational statistics & data analysis》2010,54(12):3300-3312
The forward search provides data-driven flexible trimming of a Cp statistic for the choice of regression models that reveals the effect of outliers on model selection. An informed robust model choice follows. Even in small samples, the statistic has a null distribution indistinguishable from an F distribution. Limits on acceptable values of the Cp statistic follow. Two examples of widely differing size are discussed. A powerful graphical tool is the generalized candlestick plot, which summarizes the information on all forward searches and on the choice of models. A comparison is made with the use of M-estimation in robust model choice. 相似文献
10.
ZHAO Wei 《数字社区&智能家居》2008,(24)
在网络异常检测中,为了提高对异常状态的检测率,降低对正常状态的误判率,该文提出利用TSK模糊控制系统进行网络异常检测的新方法。在对TSK模糊控制系统的训练中采取梯度下降算法,充分发挥梯度下降局部细致搜索优势。实验数据采用KDDCUP99数据集,实验结果表明,基于梯度下降的模糊控制系统提高了异常检测的准确性。 相似文献