Sterols from Mytilidae Show Anti-Aging and Neuroprotective Effects via Anti-Oxidative Activity

For screening anti-aging samples from marine natural products, K6001 yeast strain was employed as a bioassay system. The active mussel extract was separated to give an active sterol fraction (SF). SF was further purified, and four sterol compounds were obtained. Their structures were determined to be cholesterol (CHOL), brassicasterol, crinosterol, and 24-methylenecholesterol. All compounds showed similar anti-aging activity. To understand the action mechanism involved, anti-oxidative experiments, reactive oxygen species (ROS) assays, and malondialdehyde (MDA) tests were performed on the most abundant compound, CHOL. Results indicated that treatment with CHOL increases the survival rate of yeast under oxidative stress and decreases ROS and MDA levels. In addition, mutations of uth1, skn7, sod1, and sod2, which feature a K6001 background, were employed and the lifespans of the mutations were not affected by CHOL. These results demonstrate that CHOL exerts anti-aging effects via anti-oxidative stress. Based on the connection between neuroprotection and anti-aging, neuroprotective experiments were performed in PC12 cells. Paraquat was used to induce oxidative stress and the results showed that the CHOL and SF protect the PC12 cells from the injury induced by paraquat. In addition, these substance exhibited nerve growth factor (NGF) mimic activities again confirmed their neuroprotective function.     

Synthesis of 3D graphene/MnO2 nanocomposites with hierarchically porous structure for water purification

Journal of Porous Materials - In this work, a three-dimensional (3D) graphene/manganese dioxide nanocomposite (PGA/MnO2) with a hierarchically porous structure was prepared by facile steam...     

Editorial for rare metals,special issue on photocatalysis

<正>Burning of fuels is an irreversible entropy increasing process, requiring additional energies derived from the environment to let the process cycle. In theory, photon energy delivered from the sun could fix the huge energy demand in a clean and sustainable way. Photocatalysis is such an ideal approach to reconvert inert molecules directly into fuels and other chemical feedstocks using photon energy without     

浅谈人事档案管理

随着我国经济、政治体制的不断改革与深入,我国的人事档案出现了许多新的问题。为了改善这种情况,使得人事档案管理工作能够顺利地开展、与时俱进,更好地为人们服务,笔者结合多年的档案管理工作的经验,为人事档案管理提出了几条建议。     

填海地区复杂地质条件下的混凝土灌注桩施工技术

本文以深圳市后海片区百丽大厦项目混凝土灌注桩为例,分析并介绍了填海造陆地区复杂地质条件下的混凝土灌注桩技术,希望为类似工程施工提供参考。     

喷涂聚脲弹性体改性的研究进展

综述了喷涂聚脲弹性体的改性方法,重点介绍了环氧树脂、有机硅、酚醛树脂、液态聚硫橡胶改性喷涂聚脲弹性体的反应机理及改性后材料的性能变化特点.利用不同材料改性的方法,喷涂聚脲弹性体除保留原有的性能优势外,收缩率还明显减小,附着力得到改善,耐温及耐化学介质等方面性能也得以提高,扩大了其应用范围.     

基于Fuzzy理论的产品UE量化分析

通过建立用户体验模型,得到丰富的体验数据,必须对其进行量化分析,Fuzzy数学理论为该数据的分析提供了模糊评判的标准,使产品设计部门更直观地了解消费者的体验。     

实时视频传输的自适应调节方法及其应用

实时视频是互联网上的一种重要应用.在视频传输过程中,网络状况的改变会影响视频质量.在对IP网络视频传输技术研究的基础上,提出了一种用于实时视频传输的自适应调节方法.这种方法实时监测网络资源状况,在网络资源变化时采用相应的调节手段,使所传输的视频流能够适应当前网络状况.结合一个即时视频通信系统的实现,给出了这种自适应调节方法的应用方式,并进行了实际测试,显示了自适应调节功能的运行效果.     

锦城律机——中国塔机制造业的一颗"新星"

中国有句古话"少不入川、老不出川",这句话点出了巴蜀大地悠闲宜居的生活状态,某种程度上,这句话也是四川不适合奋斗创业的精辟表述.而在成都,却有一家具有30余年历史的国有制企业,经历了长达11年的亏损之后,自2004年起,在塔式起重机制造业飞速崛起,取得了骄人业绩,令客户及同行刮目相看,成为塔机行业夺目的新星,她就是四川锦城建筑机械有限责任公司(以下简称"锦城建机").     

利用双口RAM实现双机系统的通信

提出通过双口RAM的数据交换来实现对基于ISA总线和MultiBus-Ⅰ总线双机的通信方式.介绍双口RAM的数据交换、技术特征、CPLD逻辑说明及段地址选择.