2-(2-Cyanopropyl) Dithiobenzoate-mediated Grafting Polymerization of Methyl Methacrylate from Vinyl Modified Silica

Deling Li,Guanghui Li,Qing Zhang,Guixian Su,Hongxia Zhang 한국고분자학회 2016 폴리머 Vol.40 No.4

Grafting polymerization of methyl methacrylate (MMA) from vinyl modified silica mediated by 2-(2-cyanopropyl) dithiobenzoate was first conducted. Surface radicals generated by the addition reaction of “free” polymeric radicals with surface vinyl could initiate reversible addition-fragmentation chain transfer (RAFT) grafting polymerization of MMA from silica. The RAFT grafting polymerization of MMA from silica exhibited a living character, evident from the linear relationship of grafting ratio with monomer conversion. Grafting polymerization rate appeared dependent on target molecular weight and initiator concentration because of diffusion-controlled RAFT process on silica. The PMMA-grafted silica allowed for a second-step grafting polymerization due to the existence of dithioester group on the chain ends of grafted PMMA. In this case, surface radicals were generated by the reaction of “free” polymeric radicals with the surface RAFT agents, which differed from the RAFT process of grafting polymerization from vinyl modified silica. This method could be extended to prepare a variety of block copolymers from silica.

3D-QSAR and Molecular Docking Studies on Benzotriazoles as Antiproliferative Agents and Histone Deacetylase Inhibitors

Li, Xiaolin,Fu, Jie,Shi, Wei,Luo, Yin,Zhang, Xiaowei,Zhu, Hailiang,Yu, Hongxia Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.8

Benzotriazole is an important synthetic auxiliary for potential clinical applications. A series of benzotriazoles as potential antiproliferative agents by inhibiting histone deacetylase (HDAC) were recently reported. Three-dimensional quantitative structure-activity relationship (3D-QSAR), including comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA), were performed to elucidate the 3D structural features required for the antiproliferative activity. The results of both ligand-based CoMFA model ($q^2=0.647$, $r^2=0.968$, ${r^2}_{pred}=0.687$) and CoMSIA model ($q^2=0.685$, $r^2=0.928$, ${r^2}_{pred}=0.555$) demonstrated the highly statistical significance and good predictive ability. The results generated from CoMFA and CoMSIA provided important information about the structural characteristics influence inhibitory potency. In addition, docking analysis was applied to clarify the binding modes between the ligands and the receptor HDAC. The information obtained from this study could provide some instructions for the further development of potent antiproliferative agents and HDAC inhibitors.

Searching for critical failure surface in slope stability analysis by using hybrid genetic algorithm

Li, Shouju,Shangguan, Zichang,Duan, Hongxia,Liu, Yingxi,Luan, Maotian Techno-Press 2009 Geomechanics & engineering Vol.1 No.1

The radius and coordinate of sliding circle are taken as searching variables in slope stability analysis. Genetic algorithm is applied for searching for critical factor of safety. In order to search for critical factor of safety in slope stability analysis efficiently and in a robust manner, some improvements for simple genetic algorithm are proposed. Taking the advantages of efficiency of neighbor-search of the simulated annealing and the robustness of genetic algorithm, a hybrid optimization method is presented. The numerical computation shows that the procedure can determine the minimal factor of safety and be applied to slopes with any geometry, layering, pore pressure and external load distribution. The comparisons demonstrate that the genetic algorithm provides a same solution when compared with elasto-plastic finite element program.

Knee-driven many-objective sine-cosine algorithm

Hongxia Zhao,Yongjie Wang,Maolin Li 한국인터넷정보학회 2023 KSII Transactions on Internet and Information Syst Vol.17 No.2

When solving multi-objective optimization problems, the blindness of the evolution direction of the population gradually emerges with the increase in the number of objectives, and there are also problems of convergence and diversity that are difficult to balance. The many-objective optimization problem makes some classic multi-objective optimization algorithms face challenges due to the huge objective space. The sine cosine algorithm is a new type of natural simulation optimization algorithm, which uses the sine and cosine mathematical model to solve the optimization problem. In this paper, a knee-driven many-objective sine-cosine algorithm (MaSCA-KD) is proposed. First, the Latin hypercube population initialization strategy is used to generate the initial population, in order to ensure that the population is evenly distributed in the decision space. Secondly, special points in the population, such as nadir point and knee points, are adopted to increase selection pressure and guide population evolution. In the process of environmental selection, the diversity of the population is promoted through diversity criteria. Through the above strategies, the balance of population convergence and diversity is achieved. Experimental research on the WFG series of benchmark problems shows that the MaSCA-KD algorithm has a certain degree of competitiveness compared with the existing algorithms. The algorithm has good performance and can be used as an alternative tool for many-objective optimization problems.

A three-dimensional in vitro culture model for primary neonatal rat ventricular myocytes

Hongxia Zheng,Shanshan Liu,Wei-ming Tian,Hong-ji Yan,Yao Zhang,Yu Li 한국물리학회 2012 Current Applied Physics Vol.12 No.3

To overcome bad prognosis of patients with heart failure and the lack of organ donors, cardiac tissue engineering has developed as a biomimetic approach to repair, replace, and regenerate the damaged cardiac tissue. During the past decade years, researchers are devoted to find different natural and/or synthetic materials that can build appropriate physical structures to contain and organize implanted cells. In this study, we present a new method for primary neonatal rat cardiomyocytes culture in vitro using alginate/collagen/chitosan hydrogel. To investigate the feasibility of this material as scaffold for cardiac myocytes, neonatal rat ventricular myocytes were isolated and encapsulated in alginate-based beads cross-linked with calcium ion. The growth of cells was evaluated by staining with a-Sarcomeric actin (a-SCA) and Troponin T type 2 (TNNT2), and the viability of cardiomyocytes was studied in vitro by assessing the expression levels of several cardiac ion channels, including CACNL1A1, Connexin 43 and SCN5A. The results showed a significant increase in cardiac myocytes number, and the expression levels of CACNL1A1, Connexin 43 (Cx43) were up-regulated significantly except SCN5A, as compared with twodimensional cultures. Moreover, extracellular matrix produced by the seeded cells themselves was observed by staining with fibronectin. Taken together, these findings indicate that this alginate/collagen/chitosan hydrogel bead is suitable for supporting the growth and retaining the morphologic and electrophysiologic characteristics of primary cultured rat cardiac muscle cells.

3D-QSAR and Molecular Docking Studies on Benzotriazoles as Antiproliferative Agents and Histone Deacetylase Inhibitors

Xiaolin Li,Jie Fu,Wei Shi,Yin Luo,Xiaowei Zhang,Hailiang Zhu,Hongxia Yu 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.8

Benzotriazole is an important synthetic auxiliary for potential clinical applications. A series of benzotriazoles as potential antiproliferative agents by inhibiting histone deacetylase (HDAC) were recently reported. Threedimensional quantitative structure-activity relationship (3D-QSAR), including comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA), were performed to elucidate the 3D structural features required for the antiproliferative activity. The results of both ligand-based CoMFA model (q2 = 0.647, r2 = 0.968, r2 pred = 0.687) and CoMSIA model (q2 = 0.685, r2 = 0.928, r2 pred = 0.555) demonstrated the highly statistical significance and good predictive ability. The results generated from CoMFA and CoMSIA provided important information about the structural characteristics influence inhibitory potency. In addition, docking analysis was applied to clarify the binding modes between the ligands and the receptor HDAC. The information obtained from this study could provide some instructions for the further development of potent antiproliferative agents and HDAC inhibitors.

Efficient biosorption of Pb(II) from aqueous solutions by a PAH-degrading strain Herbaspirillum chlorophenolicum FA1

Xiaohui Li,Hongxia Xu,Bin Gao,Xiaoqing Shi,Yuanyuan Sun,Jichun Wu 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.57 No.-

For the first time, biosorption of lead(II) using a PAHs-degrading bacterium, Herbaspirillum chlorophenolicum FA1, was investigated as a function of initial lead concentration, biomass dosage, pH, and temperature in batch conditions. Results showed that FA1 was highly resistant to lead and grew well even at lead concentration of 200 mg L−1. The kinetic and isotherm data were well described by commonly used models, such as the pseudo-second-order and Langmuir models. Adsorption thermodynamics was spontaneous and endothermic, and FA1 exhibited a high sorption capacity of 151.52 mg g−1. SEM-EDS and FTIR analysis was conducted to further explore the interaction mechanisms.

Carbon Nanotubes Grafted with Hyperbranched Triazine Compounds

Tingting Li,HONGXIA YAN,Tianye Liu,Chao Liu,Zhengyan Chen 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2015 NANO Vol.10 No.1

In order to improve the dispersibility of carbon nanotubes (CNTs) in the resin matrix, CNTs grafted with hyperbranched triazine compound (HPTC–CNTs) was produced by four generations condensation reaction using cyanuric chloride and hexamethylenediamine. Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), UV-Vis spectroscopy (UV-Vis) and transmission electron microscopes (TEM) were used to characterize the obtained HPTC–CNTs. The FTIR, XPS, UV-Vis and TEM analysis showed that CNTs had been successfully grafted with HPTC. The TGA showed that the content of HPTC on the surface of CNTs was about 58 wt.%. And the HPTC–CNTs had good dispersion both in water and acetone.

Stenotrophomonas maltophilia HW2 enhanced cucumber resistance against cucumber green mottle mosaic virus

Hongwei Li,Wenxiang Huang,Long Xu,Xiaosi Zhou,Hongxia Liu,Zhaobang Cheng 한국식물학회 2016 Journal of Plant Biology Vol.59 No.5

Cucumber green mottle mosaic virus (CGMMV) is a major limiting factor in the production of cucumber plants worldwide. In the present study, we use plant growth-promoting rhizobacteria (PGPR) to control this virus effectively. Stenotrophomonas maltophilia HW2 was isolated from healthy cucumber root, exhibited a good biocontrol efficacy against CGMMV. Here, it is documented that 20 d after virus inoculation, the biocontrol efficacy of HW2 reached 52.61%. HW2 can effectively colonize in cucumber rhizosphere, and also promoted cucumber plants growth. We also examined the effect of HW2 on viral replication and its mechanism. Compared with the control, HW2 pre-treated plants could delay virus replication for more than 3 d and inhibit viral protein genes (CP, MP, Rep) expression in the cucumber leaf. The expression of antioxidant enzyme genes (SOD and CAT) and defense-related genes (PR1 and PR5) were quickly induced by HW2. These results suggest that HW2 induced plant defense responses to CGMMV by increasing the expression of defense response genes. We report for the first time that Stenotrophomonas maltophilia improved cucumber resistance against CGMMV, which highlights the applying of PGPR on controlling of virus diseases.

Evaluation of sex attractants for monitoring of Illiberis ulmivora Graeser (Lepidoptera: Zygaenidae: Procridinae): Height, distance, placement, climatic conditions

Liu Hongxia,Dou Rui,Wang Jifei,Zhu Yachao,Li Jingyao,Liu Jinlong,Wang Yang,Zhang Jintong,Jing Xiaoyuan 한국곤충학회 2022 Entomological Research Vol.52 No.2

The phytophagous caterpillar Illiberis ulmivora is a serious pest of Ulmus glaucescens Franch (Ulmaceae, Ulmus). In order to test potent sex attractant, field trails of synthetic candidate attractants were conducted in China. In this study, baits with ternary blends, (2S)-butyl (7Z)-dodecenoate, (2S)-butyl (9Z)-tetradecenoate, and (2S)-butyl (5Z)-decenoate (8:4:1 ratio) resulted in a higher number of male moths capture than the rest of the baits that were offered. Traps positioned at a height of 1.2 m attracted more males than those installed at heights of 2.2 m and 3.2 m. The slope aspect, temperature and humility had a significant effect on the trap catches. More catches occurred in traps placed on semi-shady and semi-sunny slopes than those placed on sunny and shady slopes. The number of pheromones in the septa decreased with age. The residual amounts of pheromones in the lures combined with 2,6-di-tert - butyl-p-cresol (BHT) were higher than those in the control. However, there were no differences in the male captures between components and components combined with BHT during the first 8 d. These findings on monitoring and trap positions can be used to predict the occurrence and population dynamics of I. ulmivora, to develop ecological management of I. ulmivora.