Dual‐micropillar‐based microfluidic platform for single embryonic stem cell‐derived neuronal differentiation

We developed the dual‐micropillar‐based microfluidic platform to direct embryonic stem (ES) cell fate. 4 × 4 dual‐micropillar‐based microfluidic platform consisted of 16 circular‐shaped outer micropillars and 8 saddle‐shaped inner micropillars in which single ES cells were cultured. We hypothesized that dual‐micropillar arrays would play an important role in controlling the shear stress and cell docking. Circular‐shaped outer micropillars minimized the shear stress, whereas saddle‐shaped inner micropillars allowed for docking of individual ES cells. We observed the effect of saddle‐shaped inner micropillars on cell docking in response to hydrodynamic resistance. We also demonstrated that ES cells cultured for 6 days within the dual‐micropillar‐based microfluidic platform differentiated into neural‐like cells. Therefore, this dual‐micropillar‐based microfluidic platform could be a potentially powerful method for screening of lineage commitments of single ES cells.     

FIPSDock: A new molecular docking technique driven by fully informed swarm optimization algorithm

The accurate prediction of protein–ligand binding is of great importance for rational drug design. We present herein a novel docking algorithm called as FIPSDock, which implements a variant of the Fully Informed Particle Swarm (FIPS) optimization method and adopts the newly developed energy function of AutoDock 4.20 suite for solving flexible protein–ligand docking problems. The search ability and docking accuracy of FIPSDock were first evaluated by multiple cognate docking experiments. In a benchmarking test for 77 protein/ligand complex structures derived from GOLD benchmark set, FIPSDock has obtained a successful predicting rate of 93.5% and outperformed a few docking programs including particle swarm optimization (PSO)@AutoDock, SODOCK, AutoDock, DOCK, Glide, GOLD, FlexX, Surflex, and MolDock. More importantly, FIPSDock was evaluated against PSO@AutoDock, SODOCK, and AutoDock 4.20 suite by cross‐docking experiments of 74 protein–ligand complexes among eight protein targets (CDK2, ESR1, F2, MAPK14, MMP8, MMP13, PDE4B, and PDE5A) derived from Sutherland‐crossdock‐set. Remarkably, FIPSDock is superior to PSO@AutoDock, SODOCK, and AutoDock in seven out of eight cross‐docking experiments. The results reveal that FIPS algorithm might be more suitable than the conventional genetic algorithm‐based algorithms in dealing with highly flexible docking problems. © 2012 Wiley Periodicals, Inc.     

T-shaped non-symmetrical twin liquid crystalline compounds

New unconventional T-shaped non-symmetrical dimeric liquid crystalline compounds have been synthesised and their thermotropic properties studied on the hot-stage of a polarising microscope. These compounds consist of an azo-ester mesogenic unit with a range of terminal substituents (–CH₃, –OCH₃, –NO₂ or –Cl) at one end, interconnected by a flexible spacer (n?=?4, 5 or 10) via ether and ester linking units to a biphenyl moiety at the lateral hydroxyl position of the azo-ester. All the compounds were characterised using a combination of elemental analysis and standard spectroscopic methods. The compounds were found to exhibit enantiotropic nematic and smectic mesophases. The effect of different terminal substituents on mesomorphism is discussed.     

Effects of combining of different flexible spacers in liquid crystal trimers and tetramers on transition properties

Liquid crystal trimers and tetramers containing two kinds of flexible spacers, namely O(CH₂) _m O and COO(CH₂) _n O, were divided into four classes according to the odd/even nature of the number of atoms in the flexible spacers: specifically, even–even, odd–odd, even–odd, and odd–even trimers, and even–even–even, odd–odd–odd, odd–even–odd, and even–odd–even tetramers. The transition properties of the four types of trimers and of tetramers were compared. Although the nematic–isotropic transition temperature and the associated entropy changes were primarily related to the number of the even-membered flexible spacers in these molecules, the different combinations of the flexible spacers significantly affected their transition properties.     

基于嵌入式的工业控制人机界面系统研究

针对工业控制系统网络化和良好人机交互性的需求,构建和开发了基于ARM9微处理器的通用工业控制人机界面系统。硬件部分主要讨论了以S3C2440微处理器为核心的硬件电路设计,外围电路模块包括SDRAM及Flash存储器电路、以太网电路、RS-232/RS-422电路、触摸屏及LCD接口等电路,在分析了硬件系统信号完整性的前提下,完成了6层PCB的设计工作。软件部分主要研究了U-Boot移植和内核裁剪技术,编写了相关的硬件设备驱动程序,设计了基于QT/Embedded的人机界面和相关应用程序。论文研究最终实现了工业控制系统的人机交互和控制需求。     

统计数据采样算法

将集中式控制系统常用的结构二层结构改进为智能化的三层结构的设计方案,即传感器、智能巡检仪和上位机。上位机既可以直接读取传感器的数据也可读取智能巡检仪的数据。此方案较好地解决了二层结构所出现的问题,并且也适合交大规模的其它类型的控制系统。这种设计方案存在当规模时上位机采集数据出现丢失现象。本文提出了利用数据库的历史数据及控制曲线的线性特征的数据采集算法,较好地解决了数据丢失的问题。并以温控系统为例仿真了在较大规模控制环境下的试验结果。     

Portable paper‐based device for quantitative colorimetric assays relying on light reflectance principle

This paper presents a novel paper‐based analytical device based on the colorimetric paper assays through its light reflectance. The device is portable, low cost (<20 dollars), and lightweight (only 176 g) that is available to assess the cost‐effectiveness and appropriateness of the original health care or on‐site detection information. Based on the light reflectance principle, the signal can be obtained directly, stably and user‐friendly in our device. We demonstrated the utility and broad applicability of this technique with measurements of different biological and pollution target samples (BSA, glucose, Fe, and nitrite). Moreover, the real samples of Fe (II) and nitrite in the local tap water were successfully analyzed, and compared with the standard UV absorption method, the quantitative results showed good performance, reproducibility, and reliability. This device could provide quantitative information very conveniently and show great potential to broad fields of resource‐limited analysis, medical diagnostics, and on‐site environmental detection.     

溶液法制备柔性压阻式传感器的研究进展

柔性压阻式传感器具有结构简单、易于制备、检测范围广等优势, 在可穿戴电子器件领域中扮演着非常重要的角色. 在制备柔性压阻式传感器的众多方法中, 溶液法由于操作简单、反应条件温和、材料的适用性广泛、易于规模化制备等优势, 成为极具发展前景的制备工艺. 在此基础上, 如何进一步提高柔性压阻式传感器的力学与电学性能也成为研究者们更加关注的话题. 另外, 制备图案化、微型化、规模化的传感器阵列为柔性压阻式传感器的应用范围拓展了新的道路. 本综述首先介绍了柔性压阻式传感器的工作原理与性能指标, 同时讨论了其性能指标对传感器在实际应用中的影响. 随后, 简单介绍了其构成材料, 并通过梳理近年来溶液法制备柔性传感器的研究成果, 选取了几种典型的溶液法制备方法进行重点介绍, 指出其具备的优势及目前存在的问题. 最后, 对溶液法制备柔性传感器的发展方向进行总结与展望.     

基于MXenes的功能纤维的制备及其在智能可穿戴领域的应用

在电子信息和物联网技术的推动下,人类对可穿戴电子器件和智能织物的需求愈发突出,功能纤维作为智能可穿戴设备的重要载体,近年来获得快速发展。功能纤维的性能很大程度上取决于纤维的基础构筑单元。过渡金属碳/氮化物(MXenes)作为一种新兴的二维材料,凭借其高电导率、优异的可加工性能、可调节的表面特性以及出色的机械强度等优点,受到了极大的关注,也逐渐成为构筑功能纤维的重要单元。本文将主要综述MXenes的湿化学、熔融盐、无氟试剂刻蚀等方法和力学、电学、光学和化学稳定性等性能,阐述基于该材料制备的功能纤维在传感、储能以及其他智能领域的应用,最后讨论了基于MXenes材料的功能纤维的未来应用前景和技术挑战。