Antimicrobial and antifouling surfaces through polydopamine bio-inspired coating

The increasing antibiotic treatment failure is attributed to the increasing emergence of drug-resistant bacteria,and the attachment of these bacteria to the surface of implantation materials often leads to dangerous bacterial biofilm formation on the implant surface.Thus,this creates an urgent need to develop new antibacterial material and antifouling implants.Polydopamine(PDA),as a musselinspired material,has many advantageous properties,such as a simple preparation procedure,excellent hydrophilicity and biocompatibility,strong adhesive performance,easy functionalization,outstanding photothermal conversion effect,and strong quenching effect.PDA has increasingly attracted much interest not only for its adherence to virtually all types of surfaces but also as it provides a simple and versatile approach to functionalize material surfaces to obtain a variety of multifunctional nanomaterials.In this review,we mainly focus on the preparation and polymerization mechanism of PDA systems and then provide a compilation of several reports on the PDA surface modification of various nanomaterials and material surfaces,including metals,metal oxides,carbons,and polymers.Finally,we summarize the advantages and disadvantages of polydopamine surface-modified nanomaterials.     

Improvement of Carbon Tetrachloride-Induced Acute Hepatic Failure by Transplantation of Induced Pluripotent Stem Cells without Reprogramming Factor c-Myc

The only curative treatment for hepatic failure is liver transplantation. Unfortunately, this treatment has several major limitations, as for example donor organ shortage. A previous report demonstrated that transplantation of induced pluripotent stem cells without reprogramming factor c-Myc (3-genes iPSCs) attenuates thioacetamide-induced hepatic failure with minimal incidence of tumorigenicity. In this study, we investigated whether 3-genes iPSC transplantation is capable of rescuing carbon tetrachloride (CCl(4))-induced fulminant hepatic failure and hepatic encephalopathy in mice. Firstly, we demonstrated that 3-genes iPSCs possess the capacity to differentiate into hepatocyte-like cells (iPSC-Heps) that exhibit biological functions and express various hepatic specific markers. 3-genes iPSCs also exhibited several antioxidant enzymes that prevented CCl(4)-induced reactive oxygen species production and cell death. Intraperitoneal transplantation of either 3-genes iPSCs or 3-genes iPSC-Heps significantly reduced hepatic necrotic areas, improved hepatic functions, and survival rate in CCl(4)-treated mice. CCl(4)-induced hepatic encephalopathy was also improved by 3-genes iPSC transplantation. Hoechst staining confirmed the successful engraftment of both 3-genes iPSCs and 3-genes iPSC-Heps, indicating the homing properties of these cells. The most pronounced hepatoprotective effect of iPSCs appeared to originate from the highest antioxidant activity of 3-gene iPSCs among all transplanted cells. In summary, our findings demonstrated that 3-genes iPSCs serve as an available cell source for the treatment of an experimental model of acute liver diseases.     

逐维改进的布谷鸟搜索算法

布谷鸟搜索(cuckoo search,简称CS)算法是一种新兴的仿生智能算法,对解采用整体更新评价策略.在求解多维函数优化问题时,由于各维之间相互干扰,采用整体更新评价策略将恶化算法的收敛速度和解的质量.为了弥补此缺陷,提出了基于逐维改进的布谷鸟搜索算法.在改进算法的迭代过程中,针对解采用逐维更新评价策略.该策略将各维的更新值与其他维的值组合成新的解,并采用贪婪方式接受能够改善解质量的更新值.实验结果说明,改进策略能够有效地提高CS 算法的收敛速度并改善解的质量.与相关的改进布谷鸟搜索算法以及其他演化算法的比较结果表明,改进算法在求解连续函数优化问题上是具有竞争力的.     

秋收季节稻草燃烧粒子大气脱水醣类成分与粒径分布研究

以台湾中南部水稻作物区域为目标,探讨秋收稻草燃烧烟尘大气脱水醣类粒径分布成分特征;以改良离子层析仪解析3种大气悬浮粒子(PM2.5、PM10、总悬浮颗粒(TSP))大气脱水醣类成分浓度(左旋葡萄糖、甘露聚糖)与粒径分布,并探讨稻草燃烧对大气粒子的贡献率。结果显示,稻草燃烧期间大气(乡村/市郊)两种粒子(PM2.5与TSP)左旋葡萄糖浓度均大幅上升,两种粒子收成燃烧期间较非收成季节升高约5.5倍(较收成季节背景PM2.5与总悬浮颗粒分别高1.21倍与1.40倍)严重影响区域空气质量。市郊含左旋葡萄糖粒子分布以PM2.5细微粒为主(占TSP81%以上);乡村左旋葡萄糖粒径分布较广,PM2.5粒子占TSP56%左右,粗大粒子(PM>10)占总悬浮颗粒的35%。此外,结果显示稻草生物质燃烧对区域PM2.5粒子平均贡献率为12%,市郊稍高于乡村(乡村、市郊平均贡献率分别为10.5%、13.0%),显现稻草生物质燃烧对台湾中南部空气质量有严重影响。     

电镀超硬磨料工艺的改进及参数优化

电镀磨料法是制造超硬磨料工具的常用方法,电镀质量直接影响到电镀超硬磨料工具的寿命和使用性能,而电镀工艺是影响电镀质量的主要因素.文中首先对原有的电镀基础工艺中镀前处理及镀底镍工序进行了改进,提出了镀前处理中增加去毛刺、电化学除油、阳极处理等过程及镀底镍工序中带电入槽和冲击电流的一套新的电镀工艺,并进行了实验研究,结果表明:新的工艺增强了镀层的结合力,提高了电镀质量;其次实验研究了电镀液配方及电流密度、镀液温度、PH值等工艺参数对电镀质量的影响,并得到了优化结果.     

一种高效低能耗移动数据采集与无线充电策略

在无线可充电传感器网络(wireless rechargeable sensor network,简称WRSN)中,所面临的一项重要挑战是如何在高效收集传感器节点数据的同时,降低网络整体能量消耗.大多数现有数据收集策略或是不能适应大规模的充电传感器网络,或是没有充分考虑到传感器节点能量补充的问题,这将严重降低网络的通信...     

光谱检测技术在禽蛋品质评价中的应用研究进展

禽蛋营养丰富，是居民饮食结构中的重要的成分组成部分。禽蛋品质的优劣影响其产品功能特性、消费者的购买意愿, 因此实现禽蛋品质精准检测十分重要。传统的禽蛋品质检测方法存在样品损坏、耗时等问题, 而无损检测技术可以在不破坏禽蛋完整性的前提下提供准确、快速的分析结果。无损检测技术中最常用的是光谱检测技术, 光谱分析作为一种成熟的检测方法, 是建立禽蛋蛋品质检测系统的有效工具。本文概述了禽蛋品质的传统检测方法的优缺点, 并系统阐述了光谱检测技术在禽蛋品质分析上的应用, 包括可见-近红外光谱、拉曼光谱、高光谱成像、脉冲红外热成像及介电光谱。同时, 本文提出了光谱检测技术在禽蛋品质分析中存在的问题, 如光谱信息没有选择性、现有分析模型难以系统化等。未来如何更好地结合光谱技术与科学分析技术, 实现无损、快速、环保的禽蛋品质无损检测, 是禽蛋品质无损检测研究中仍需解决的关键问题。本综述为禽蛋品质无损检测技术的快速发展提供理论参考, 为满足禽蛋行业的实际生产需求指明方向。