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Polydimethylsiloxane (PDMS) with exceptional fouling-release properties is extremely susceptible to the microfouling resulted from the colonization of the pioneer microorganisms in the marine environment. In this study, six carboxyl-modified multi-walled carbon nanotubes (cMWNTs) nanoparticles were incorporated into the PDMS matrix, respectively, in order to produce the cMWNTs-filled PDMS nanocomposites (CPs) with improved antifouling (AF) properties. The AF properties of the six CPs were examined via the field assays conducted in Weihai, China. The effects of the anti-biofouling potential of the CPs (i.e. the P3 surface) on the colonization of the pioneer prokaryotic and eukaryotic microbes were investigated using the single-stranded conformation polymorphism technique via the comparison of the diversity indices. Different CPs have displayed differential and better AF properties as compared to that of the unfilled PDMS (P0). The P3 surface has exhibited exceptional anti-biofouling capacity compared with the other CPs surfaces, which can effectively prevent biofouling for more than 14 weeks in the field. The SSCP analysis revealed that the P3 surface may have significant modulating effect on the pioneer microbial communities. The pioneer eukaryotic microbes seemed more susceptible than the pioneer prokaryotic microbes to be subjected to the major perturbations exerted by the P3 surface. The dramatically reduced eukaryotic-microbial diversity may contribute to the impeding and weakening of the development and growth of the biofilm. The P3 surface has the potential to be used for future maritime applications. 相似文献
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Mo Hui-Juan Sun Yan-Xiang Zhu Xiao-Li Wang Xing-Fen Zhang Yan Yang Jun Yan Gui-Jun Ma Zhi-Ying 《Planta》2016,243(4):1023-1039
Planta - Cotton S-adenosylmethionine decarboxylase-, rather than spermine synthase-, mediated spermine biosynthesis is required for salicylic acid- and leucine-correlated signaling in the defense... 相似文献
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Ling Wang Yu Wang Yiguang Tian Jinling Shang Xiaoou Sun Hongzhuan Chen Hao Wang Wen Tan 《Bioorganic & medicinal chemistry》2017,25(1):360-371
A series of novel chalcone-rivastigmine hybrids were designed, synthesized, and tested in vitro for their ability to inhibit human acetylcholinesterase and butyrylcholinesterase. Most of the target compounds showed hBChE selective activity in the micro- and submicromolar ranges. The most potent compound 3 exhibited comparable IC50 to the commercially available drug (rivastigmine). To better understand their structure activity relationships (SAR) and mechanisms of enzyme-inhibitor interactions, kinetic and molecular modeling studies including molecular docking and molecular dynamics (MD) simulations were carried out. Furthermore, compound 3 blocks the formation of reactive oxygen species (ROS) in SH-SY5Y cells and shows the required druggability and low cytotoxicity, suggesting this hybrid is a promising multifunctional drug candidate for Alzheimer’s disease (AD) treatment. 相似文献
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Chou I-Chiang Lee Shyh-Yuan Wu Ming-Chang Chia-Wei Sun 《Computer methods in biomechanics and biomedical engineering》2014,17(5):516-526
The aims of this study were to examine the effect of implant neck design and cortical bone thickness using 3D finite element analysis and to analyse the stability of clinical evidence based on micromotion and principal stress. Four commercial dental implants for a type IV bone and maxillary segments were created. Various parameters were considered, including the osseointegration condition, loading direction and cortical bone thickness. Micromotion and principal stresses were used to evaluate the failure of osseointegration and bone overloading, respectively. It was found that the maximum stress of the peri-implant bone decreased as cortical bone thickness increased. The micromotion level in full osseointegration is less than that in non-osseointegration and it also decreases as cortical bone thickness increases. The cortical bone thickness should be measured before surgery to help select a proper implant. In the early stage of implantation, the horizontal loading component induces stress concentration in bone around the implant neck more easily than does the vertical loading component, and this may result in crestal bone loss. 相似文献