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Chen L.,Fujian Institute of Education | Xie X.,Ningde Teachers College
Nonlinear Analysis: Real World Applications | Year: 2011

In this paper, we consider an N-species cooperation system with continuous time delays and feedback controls. By applying a new integral inequality, we obtain a set of sufficient conditions which ensure the permanence of the system. Our result shows that feedback control variables have no influence on the permanence of the system, thus improving the corresponding results of Chen, Liao and Huang [F.D. Chen, X.Y. Liao, Z.K. Huang, The dynamic behavior of N-species cooperation system with continuous time delays and feedback controls, Applied Mathematics and Computation 181 (2) (2006) 803815]. © 2010 Published by Elsevier Ltd. All rights reserved.

Huang J.,Beijing Institute of Technology | Huang J.,Fujian Institute of Education | Fang H.,Beijing Institute of Technology | Chen J.,Beijing Institute of Technology | And 2 more authors.
Journal of Advanced Computational Intelligence and Intelligent Informatics | Year: 2014

Most previous studies ofmulti-agent systems only considered the first- and second-order dynamics. In this review, we present the major results and progress related to distributed high-order linear multi-agent coordination. We also discuss the current challenges and propose several promising research directions, as well as open problems that demand further investigation.

Chen G.,Huaqiao University | Chen G.,Fujian Institute of Education | Lin H.,Huaqiao University | Pu J.,Huaqiao University
Qiangjiguang Yu Lizishu/High Power Laser and Particle Beams | Year: 2011

Generation of bottle beam by modulating the spatial coherent coefficient of partially coherent beams is investigated. Based on the theorem of van Cittert-Zernike and scalar diffractive theory, partially coherent beam with particular coherent coefficient is constructed. And focused properties of this kind of partially coherent beam is studied. Based on theoretical results, an optical system to achieve the special partially coherent beams, and focus partially coherent beams with a thin lens is designed. The results indicate that particular partially coherent beams can be converted into bottle beam after focusing by thin lens. Moreover, the influence of parameters of optical system and focus length of thin lens on construction of the bottle beam is studied. The greater of lens focal length and interception ratio, the larger size of the bottle beam.

Wu J.,Fujian University of Traditional Chinese Medicine | Wan Z.,Fujian University of Traditional Chinese Medicine | Yi J.,Fujian Institute of Education | Wu Y.,Fujian University of Traditional Chinese Medicine | Peng W.,Chongqing Medical University
Journal of Natural Medicines | Year: 2013

The aim of this study was to evaluate antioxidant activities and cytotoxicity against human tumor cell lines of extracts from Bidens pilosa Linn. var. radiata Sch. Bip. (BP). Total phenolic and flavonoid contents of the extracts were determined by ultraviolet spectrophotometry. Furthermore, the antioxidant properties of different polarity fractions extracted from BP were evaluated using DPPH and ABTS radical scavenging test and FRAP assay. The ethyl acetate fraction (EE-BP) showed the highest antioxidant activity compared to other fractions. In addition, the anti-proliferative activities of the extracts on four human tumor cells, namely MCF-7, HepG2, MGC 803 and RKO, were investigated by MTT method. The EE-BP displayed the most remarkable anti-proliferative effect against the tumor cells, particularly RKO cell in dose- and time-dependent manner. The antioxidant activities and cytotoxicity correlated highly with the total phenolic and flavonoid contents, respectively. Furthermore, The active ingredient BP-6, namely 5,7,4′-trihydroxy-3, 3′-dimethyl-flavonol, was isolated and purified with the purity above 99.00% and content of 0.15% in EE-BP detected by HPLC, which could significantly inhibit the proliferation of RKO cells with the IC50 value of 6.66 μmol/l. In order to characterize the apoptotic RKO cells, flow cytometry and DNA fragmentation assay were performed. Apoptotic cell numbers increased in a dose-dependent manner after the treatment with different concentrations of EE-BP and BP-6 for 12 and 6 h, respectively. DNA ladders in apoptotic RKO cells could be easily visualized when exposed to 200 μg/ml of the EE-BP for 36 h. Taken together, our work indicated that BP had potentially therapeutic value against colorectal cancer. © 2012 The Japanese Society of Pharmacognosy and Springer.

Wu J.-G.,Fujian University of Traditional Chinese Medicine | Peng W.,Chongqing Medical University | Zeng P.-Y.,Fujian University of Traditional Chinese Medicine | Wu Y.-B.,Fujian University of Traditional Chinese Medicine | And 2 more authors.
Genetics and Molecular Research | Year: 2013

We evaluated the antibacterial activity and cytotoxicity of endophytes isolated from Scapania verrucosa Heeg., which belongs to the liverwort class. A total of 49 endophytic fungi were isolated from S. verrucosa and classified into seven genera and one family in our previous study. In this study, the cytotoxic activity of the endophytes was assessed using the brine shrimp lethality bioassay, seven of which showed potent toxicity against the brine shrimp with 50% lethal concentration values less than 20 μg/mL. T-30 was the most toxic, with a 50% lethal concentration value of 7.15 μg/mL. Moreover, T-27 exhibited the strongest antibacterial activity against Staphylococcus aureus, with minimal inhibitory concentrations below 0.25 and 4 mg/mL, which can inhibit the growth of two standard strains - ATCC 25923 (methicillin-sensitive S. aureus) and ATCC 43300 (methicillin-resistant S. aureus) - in a time-dependent manner, respectively. These results suggest that endophytes in S. verrucosa are the sources for the production of natural bioactive products and thus warrant further investigation. © FUNPEC-RP.

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