Chen Peng
Yang Weikang
Tian Yaping
Sun Shutao
Chen Guangyu
Zhang ChunYan
Ma Fuxin
Xun Yiping
Shi Lili
Yang Chunhe
Zhao Lanqing
Zhou Yabin
Du Hongwu
Pietropaolo Massimo
This paper is concerned with the controller design of networked control systems. The continuous time plant with parameter uncertainty and state delay is studies. A new model of the networked control system is provided under consideration of the nonideal network conditions. In terms of the given model, a controller design method is proposed based on a delay dependent approach. The maximum allowable synthetical bounds related with the discarded data packet and network-included delay and the feedback gain of a memoryless controller can be derived by solving a set of linear matrix inequalities for the stabilizablity of the networked control system based on Lyapunov functional method. An example is given to show the effectiveness of our method.
Chen Peng
Han Wang
Rui Guo
Mingwu Shen
Xueyan Cao
Meifang Zhu
Guixiang Zhang
Xiangyang Shi
Functionalized dendrimer-entrapped gold nanoparticles (Au DENPs) are of scientific and technological interest in biomedical applications. In this study, Au DENPs prepared with amine-terminated generation 5 (G5) poly(amido amine) dendrimers as templates were subjected to acetylation to neutralize the positive surface charge of the particles. By varying the molar ratio of Au salt to G5 dendrimer, we prepared acetylated Au DENPs with a size range of 2-4 nm. Meanwhile, we attempted to add glucose to the dialysis liquid of the acetylated Au DENPs to prevent possible particle aggregation after lyophilization. The acetylated Au DENPs with different compositions (Au salt/dendrimer molar ratios) were characterized with 1H-NMR, transmission electron microscopy, ultraviolet-visible (UV-vis) spectrometry, and zeta-potential measurements. We show that when the molar ratio of Au salt to dendrimer was equal to or larger than 75:1, the acetylated Au DENPs showed a significant aggregation after lyophilization, and the addition of glucose was able to preserve the colloidal stability of the particles. X-ray absorption measurements showed that the attenuation of the acetylated Au DENPs was much higher than that of the iodine-based contrast agent at the same molar concentration of the active element (Au vs iodine). In addition, the acetylated Au DENPs enabled X-ray computed tomography (CT) imaging of mice after intravenous injection of the particles. These findings suggest a great potential for acetylated Au DENPs as a promising contrast agent for CT imaging applications. copy 2010 Wiley Periodicals, Inc.
This paper proposes a method for robust state feedback controller design of networked control systems with interval time-varying delay and nonlinearity. The key steps in the method are to construct an improved interval-delay-dependent Lyapunov functional and to introduce an extended Jessen's inequality. Neither free weighting nor model transformation is employed in the derivation of system stability criteria. It is shown that the maximum allowable bound on the nonlinearity could be computed through solving a constrained convex optimization problem; and the maximum allowable delay bound and the feedback gain of a memoryless controller could be derived by solving a set of linear matrix inequalities. Numerical examples are given to demonstrate the effectiveness of the proposed method. Copyright copy2007 John Wiley & Sons, Ltd.
Hong-Wei Chen
Xiao-Dong Huang
Hong-Chen Li
Song He
Run-Zhou Ni
Cui-Hua Chen
Chen Peng
Gang Wu
Gui-Hua Wang
Ying-Ying Wang
Yun-Hong Zhao
Yi-Xin Zhang
Ai-Guo Shen and Hui-Min Wang
FOXJ1 is a member of the forkhead box (FOX) family of transcription factors. Recent studies suggested that FOXJ1 may function as a tumor suppressor gene in breast cancer. To investigate the potential roles of FOXJ1 in hepatocellular carcinoma (HCC), expression of FOXJ1 was first examined in eight paired frozen HCC and adjacent noncancerous liver tissues by Western blot, and we found that FOXJ1 was upregulated in HCC specimens. In addition, immunohistochemistry was performed to confirm our results in 108 HCC samples. Moreover, we also evaluated its relation with clinicopathological variables and the prognostic significance. The data showed that high expression of FOXJ1 was associated with histological grade (P < 0.001), and FOXJ1 was positively correlated with proliferation marker Ki-67 (P < 0.01). Univariate analysis suggested that FOXJ1 expression was associated with poor prognosis (P < 0.001). Multivariate analysis indicated that tumor grade (P < 0.0001), metastasis (P = 0.0451), tumor size (P = 0.0459), FOXJ1 (P = 0.0011), and Ki-67 (P = 0.0006) were independent prognostic markers for HCC. Furthermore, we noted that there existed the change of the level of FOXJ1 subcellular localization during cell-cycle transition in HepG2 cells by immunofluorescence and cell fractionation. Besides, we employed FOXJ1 overexpression/knockdown approaches to investigate the effects of FOXJ1 on HCC cell proliferation and cell-cycle distribution and found that overexpression of FOXJ1 can promote tumor cell proliferation and cell-cycle transition. Our results suggested that FOXJ1 was overexpressed in HCCs and associated with histological grade and poor prognosis. Overexpression of FOXJ1 was also involved in tumor cell proliferation and cell-cycle progression in HCC cell lines.
Modeling cybersecurity risks is an important, yet challenging, problem. In this paper, we initiate the study of modeling multivariate cybersecurity risks. We develop the first statistical approach, which is centered at a Copula-GARCH model that uses vine copulas to model the multivariate dependence exhibited by real-world cyber attack data. We find that ignoring the due multivariate dependence causes a severe underestimation of cybersecurity risks. Both simulation and empirical studies show that the proposed approach leads to accurate predictions of multivariate cybersecurity risks.