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关键词： Sericin   Melanogenesis   UVA   Primary melanocyte cells   Proteomic analysis   INDUCED APOPTOSIS   IN-VITRO   PROTEIN   ANTIOXIDANT   TYROSINASE   INFLAMMATION   INHIBITION   PATHWAY  

摘要： UV radiation causes excess production of melanin as a result of hyperpigmentation and skin disorders. Silk sericin exhibited bioactivities to skin and inhibited UV-induced phototoxicity and melanogenesis in skin cells; however, the mechanism related to sericin against UV-induced melanogenesis has not been investigated. This study aimed to investigate the protective effects of Thai silk sericins against UVA-induced phototoxicity and melanogenesis and their related mechanisms. Thai silk sericins exhibited cytoprotective effects against UV-induced toxicity in human primary melanocytes by attenuation of cytotoxicity, intracellular ROS generation, and mitochondrial potential impairment. Pre- and post-treatment with sericin significantly inhibited melanin synthesis and tyrosinase activity against UVA exposure. In addition, sericin S2 could reduce the basal melanin content in zebrafish embryos. The proteomic analysis demonstrated that Thai silk sericins altered the protein expression in melanocytes especially proteins related to stress, inflammatory, cytokine stimulation, cell proliferation, and cell survival processes that contribute to cytopmtective effect and inhibitory effect on melanogenesis of sericin. Moreover, we demonstrated the novel mechanism of Thai silk sericins in inhibiting UVA-induced melanogenesis via increasing BMP4 expression in MAPK/ERK signaling pathway. These evidences support the potential use of Thai silk sericins in prevention of hyperpigmentation in skin disorders especially after UVA exposure.

关键词： IN-SITU SYNTHESIS   LIGHT-SCATTERING   MELANIN   NANOPARTICLES   POLYDOPAMINE   ORGANIZATION   POLYMERS  

摘要： Eumelanin exhibits a defined supramolecular buildup that is deprived of at least three distinct particle species. To enable the full potential of its promising material properties, access to all particle types is crucial. In this work, the first protocol for the synthesis of the intermediate type-A particles in pure and stable dispersion form is described. It is found that aggregation of type-A particles into the larger type-B variant can be inhibited by a strict pH control during the synthesis. The exact influence of pH on the supramolecular buildup is investigated via a combination of time-resolved light scattering, electron microscopy, and UV-vis spectroscopy. It is observed that a rapid buildup of type-B particles occurs without pH control and is generally dominant at lower pH values. At pH values above 6.2 however, type-A particles are gained, and no further aggregation occurs. Even more, lowering the pH of such a stable type-A dispersion at a later stage lifts the inhibition and again leads to the formation of larger particle species. The results confirm that it is easily possible to halt the aggregation of eumelanin substructures and to access them in the form of a stable dispersion. Moreover, a profound additional understanding of the supramolecular buildup is gained by the in-depth investigation of the pH influence.

关键词： 建筑分类   建筑特征   建筑设计  

摘要： 随着我国经济的快速发展,建筑行业也在迅速崛起,为了使其更好地适应时代的要求,装配式建筑设计要点和过程中存在很多问题值得我们去探讨。文章对目前建筑工程施工现场出现比较普遍、影响比较大的是混凝土浇筑工程与预制模板安装工程等常见问题进行了分析总结并提出了解决方案以供参考借鉴意义,同时从设计理念、材料选择及构件加工工艺方面来论述,为今后在建筑行业更好地应用装配式的相关工作提供一定帮助和意见建议。

关键词： 手术期间   阳台   喇叭花   寄寓   母亲  

摘要： 每户城里人家的阳台上,都少不了花草的点缀,我家阳台上的保留品种是喇叭花。小小的喇叭花,寄寓着獅母亲一段永难忘却的记忆。那年秋季里父亲病故,半年后,刚参加工作的我又害了一场大病,手术期间,相处两年的对象也弃我而去……出院后身体虚弱的我只能跑到农场里,在母亲身边休养康复。

关键词： 超大规格陶瓷饰面板   铝型材框   装配式装修   干挂技术  

摘要： 超大规格陶瓷饰面板材是瓷抛砖创新升级产品。具有天然石材的质感,色彩、纹理更接近石材。常应用于公建装饰工程。目前超大规格陶瓷饰面板的施工尚无标准可循,受板材尺寸和重量限制,施工现场内的运输效率低,易磕碰。北京城建集团基于城奥大厦精装修工程施工需要,研制出超大规格陶瓷饰面板装配施工技术,灵活运用装配式安装思路,工厂化加工铝型材框,标准化粘结裁切,现场装配安装。缩短现场施工流程,优化工序安排,利于其他专业穿插施工,减少现场裁切和湿作业,达到缩短工期、质量优化、降低成本的目的。利用现场条件研制的运输工具,提高运输效率。对此类超大规格陶瓷饰面板施工具有借鉴意义。

关键词： 港城互动   土地利用   RCI   功能分区  

摘要： 港城关系就是指港口城市与其辖区内港口之间的相互需求、相互作用和相互制约的关系。港口与城市之间的协调发展是实现港城互动,提升港口城市竞争力的重要途径。从岸线变化、土地利用变化、城市功能分区变化和RCI指数变化四方面系统综合地对新加坡港、巴西古当港和丹戎帕拉帕斯港的港城互动发展进行了比较分析。结果表明:3个港口中新加坡港发展稳定,其港城互动达到理想状态,可以共融发展;丹戎帕拉帕斯港则港口功能远高于城市功能,处于极不平衡状态,城市只是进出口交通的转换点;巴西古当港则是城市功能略高于港口功能,城市对港口依赖性逐渐减少。3个港口发展差异性源于地理条件、城市规划及政策等的显著影响,其发展经验对我国港口城市发展可以提供一定的借鉴。