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1.
《Arabian Journal of Chemistry》2022,15(10):104145
In the present study, novel representatives of the important group of biologically-active, dehydroabietic acid-bearing dithiocarbamate moiety, were synthesized and characterized by 1H NMR, 13C NMR, HR-MS. The in vitro antiproliferative activity evaluation (MTT) indicated that these compounds exhibited potent inhibitory activities in various cancer cell lines (HepG-2, MCF-7, HeLa, T-24, MGC-803). Particularly, compound III-b possessed extraordinary cytotoxicity with low micromolar IC50 values ranging from 4.07 to 38.84 µM against tested cancer cell lines, while displayed weak cytotoxicity on two normal cell lines (LO-2 and HEK 293 T). Subsequently, the potential mechanisms of representative compound III-b were elementarily investigated by Transwell experiment, which showed III-b can inhibit cancer cells migration. Annexin-V/PI dual staining showed that the compound can induce HepG-2 cells apoptosis in a dose-dependent manner. Meanwhile this apoptosis may be related to the upregulated protein expression of cleaved-caspase 3, cleaved-caspase 9, Bax and downregulated of Bcl-2 indicated by Western Blot. Later study further confirmed that ROS levels in HepG-2 cells increased significantly with the rise of concentrations. In addition, through the network pharmacology data analyzing, the core targets and signaling pathways of compound III-b for treatment of liver neoplasms were forecasted. Molecular docking model showed that compound III-b had high affinity with hub targets (CASP3, EGFR, HSP90AA1, MAPK1, ERBB2, MDM2), suggesting that compound III-b might target the hub protein to modulate signaling activity. Taken together, these data indicated that dehydroabietic acid structural modification following the “Molecular hybridization” principle is a feasible way to discover the potential multi-targeted antitumor compounds. 相似文献
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《Discrete Mathematics》2022,345(10):112999
Ryser proved that any two tournaments with the same score sequence are -equivalent while Beineke and Moon proved the -equivalence for any two bipartite tournaments with the same score lists. In this paper, we extend these results to orientations of G vertex-multiplications. We focus on two main areas, namely orientations with the same score list and with score-list parity. Our main tools are extensions of the refinement technique, directed difference graph and a reduction lemma. 相似文献
4.
Multi‐switching combination–combination synchronization of non‐identical fractional‐order chaotic systems 下载免费PDF全文
In this paper, multi‐switching combination–combination synchronization scheme has been investigated between a class of four non‐identical fractional‐order chaotic systems. The fractional‐order Lorenz and Chen's systems are taken as drive systems. The combination–combination of multi drive systems is then synchronized with the combination of fractional‐order Lü and Rössler chaotic systems. In multi‐switching combination–combination synchronization, the state variables of two drive systems synchronize with different state variables of two response systems simultaneously. Based on the stability of fractional‐order chaotic systems, the multi‐switching combination–combination synchronization of four fractional‐order non‐identical systems has been investigated. For the synchronization of four non‐identical fractional‐order chaotic systems, suitable controllers have been designed. Theoretical analysis and numerical results are presented to demonstrate the validity and feasibility of the applied method. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
5.
矿井通风系统具有随机性、模糊性和不确定性等特征,一般单一的赋权评价法难以对其进行准确的优化评价.采用模糊层次分析法和熵权法的组合赋权法不仅可以提升对目标评价的准确性还能避免单一赋权的偶然性和局限性,结合可拓学的优度评价法,依据优度排序,得到最优方案.事实证明,基于组合赋权的可拓评价模型较其他评价方法更为客观,评价结果更加符合实际,可为解决类似优化方案问题提供一种新思路和方法. 相似文献
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平面膜结构拓扑优化的有无复合体方法 总被引:18,自引:3,他引:18
将作者对桁架在应力约束下结构拓扑优化的有无复合体模型发展到平面膜结构在应力、位移约束下结构拓扑优化的建模与求解。同时提出了该模型的有效解法,获得了令人满意的数值结果。本文工作表明独立连续拓扑变量的提出对于结构拓扑优化的研究是有意义的。 相似文献
8.
Asymptotic synchronization of continuous/discrete complex dynamical networks by optimal partitioning method 下载免费PDF全文
The synchronization problem for both continuous and discrete‐time complex dynamical networks with time‐varying delays is investigated. Using optimal partitioning method, time‐varying delays are partitioned into l subintervals and generalized results are derived in terms of linear matrix inequalities (LMIs). New delay‐dependent synchronization criteria in terms of LMIs are derived by constructing appropriate Lyapunov–Krasovskii functional, reciprocally convex combination technique and some inequality techniques. Numerical examples are given to illustrate the effectiveness and advantage of the proposed synchronization criteria. © 2014 Wiley Periodicals, Inc. Complexity 21: 193–210, 2015 相似文献
9.
为了提高采用转台对惯导系统和惯性仪表进行误差模型标定时的可靠性和精度,对角位置转台的控制系统进行了研究。首先借助NI公司PXI-8101控制器和功能强大的数据采集卡PXIe-6363对转台控制系统进行了硬件设计。随后在对转台常规PID控制方法研究的基础上提出了一种能随系统调节偏差自动改变积分项累加速度的变速PID控制方法。接着又对基于软件实现的双通道旋转变压器轴角解调算法进行了研究并提出了一种粗精组合角纠错方法。最后对本文设计的转台控制系统进行了测试实验,结果表明提出的轴角解调算法具有较好的解码速度和精度,并且变速PID控制方法大大提高了转台控制系统的自学习能力和鲁棒性,显著地改善了转台控制过程的稳定性。 相似文献
10.
在图像处理过程中, 为了在图像去噪时更好地保留图像边缘细节信息, 首先结合扩散系数和曲率的性质建立了一个曲率平滑模型. 考虑到图像受到噪声污染时曲率会发生显著变化, 将图像的水平集曲率作为一个检测因子代入到上述模型中, 提出了一个梯度与曲率相结合的新模型. 分析与仿真结果表明, 该模型与Perona-Malik模型相比较保留了更多的图像信息, 有效地增强了图像尖锐的边缘, 同时很好地保持了图像的直线和曲线边缘、角点、斜坡和小尺度特征, 是一个理想的模型. 相似文献