Arraying Cell Cultures Using PEG‐DMA Micromolding in Standard Culture Dishes

A robust and effortless procedure is presented, which allows for the microstructuring of standard cell culture dishes. Cell adhesion and proliferation are controlled by three‐dimensional poly(ethylene glycol)‐dimethacrylate (PEG‐DMA) microstructures. The spacing between microwells can be extended to millimeter size in order to enable the combination with robotic workstations. Cell arrays of microcolonies can be studied under boundary‐free growth conditions by lift‐off of the PEG‐DMA layer in which the growth rate is accessible via the evolution of patch areas. Alternatively, PEG‐DMA stencils can be used as templates for plasma‐induced patterning.

     

Responsive polymers for analytical applications: A review

Stimuli-responsive polymers are capable of translating changes in their local environment to changes in their chemical and/or physical properties. This ability allows stimuli-responsive polymers to be used for a wide range of applications. In this review, we highlight the analytical applications of stimuli-responsive polymers that have been published over the past few years with a focus on their applications in sensing/biosensing and separations. From this review, we hope to make clear that while the history of using stimuli-responsive polymers for analytical applications is rich, there are still a number of directions to explore and exciting advancements to be made in this flourishing field of research.     

Chemistry of bicyclic 5-6 systems: Synthesis of oxazolo[3,2-a]pyridines and their salts with a ring-junction nitrogen atom

The present review highlights the synthetic procedures reported for the preparation of oxazolo[3,2-a]pyridines as a class of 5-6 bicyclic heterocycles with a nitrogen atom at the ring junction. The different sections included the synthesis of the investigated analogs through the reactions of (1) β-ketoesters with α,β-unsaturated ketones (2) δ-oxoacids or esters or unsaturated carboxylic acids with glycinol derivatives (3) unsaturated ketoesters with enamines (4) ethoxymethylenes with amidoglycinol derivatives (5) pyridinium salts with phenylglycinol (6) Multicomponent reactions, and (7) Synthesis of tetracyclic systems. The aim of the present study is to demonstrate a synopsis of the synthesis of compounds containing oxazolo[3,2-a]pyridine skeleton with high yields using readily and accessible starting materials, and efficient synthetic routes until now. The stereochemistry of the obtained enantiopure heterocycles, the isolation of the isomers and the reaction mechanisms of the unexpected products are discussed.     

Orthoconic antiferroelectric liquid crystals

The ubiquitous liquid crystal display (LCD) is based on nematic liquid crystals (LCs) and has during 40 years developed from simple few digit displays into high-resolution flat-panel displays. A last and very important step towards the present TVs was the combination with thin film transistors that also led to the introduction of several new switching modes. Despite the enormous success of this technology, there is presently a renewed interest in LCs with faster electrooptic response, especially for future 3D vision display systems and possibly for field-sequential-colour (FSC) generation displays. Here, I focus on the so-called orthoconic antiferroelectric LCs (OAFLCs), which can provide the fast switching of conventional antiferroelectric LCs, but combined with a potentially much higher optical contrast. The reason is that the dark state of orthconic materials has a homeotropic optic axis, which makes the extinction ideally complete between crossed polarisers and independent of in-plane alignment fluctuations characteristic of all antiferroelectric LCs. The basic features and device physics issues of orthoconic LCs are reviewed and the most important remaining challenges to be met in terms of materials development are discussed in this article. Furthermore, a few examples of new applications made possible with the use of present and future orthoconic materials are given.     

氨三乙酸、缬氨酸、亮氨酸的三元过渡金属配合物：合成和生物学应用

以氨三乙酸HNTA2-为主要配体,缬氨酸(valine)或亮氨酸(leucine)为次要配体在微酸性介质中合成了Ni(Ⅱ),Cu(Ⅱ),and Zn(Ⅱ)的三元配合物。用元素分析、热分析、FTIR,UV-Vis分光光度法,磁性测量和质谱法表征了合成的三元配合物。结果表明,三元配合物可在金属(M):氨三乙酸(HNTA)∶缬氨酸(valine)或亮氨酸(leucine)=1∶1∶1时制得,其分子结构为[M(HNTA)(valine)(H2O)2].1.5H2O and[M(HNTA)(leucine)(H2O)2].1.5H2O(其中M=Ni(Ⅱ)or Cu(Ⅱ))和H2[Zn(NTA)(valine)(H2O)]H2O。标题三元过渡金属配合物为八面体对称构型。同时研究了该三元配合物对大肠杆菌,金黄色葡萄球菌,白色念珠菌,黄曲霉菌(菌株从开罗大学理学院微分析中心获得)的抗菌活性。根据推荐的知名方法用标准的抗菌和抗真菌剂进行体外测试(in vitro)以评估我们的新制备的配合物对细菌和真菌物种的生长抑制活性。     

On Nash approximation of complex analytic sets in Runge domains

We prove that every complex analytic set X in a Runge domain Ω   can be approximated by Nash sets on any relatively compact subdomain _Ω0${\Omega }_0$ of Ω. Moreover, for every Nash subset Y of Ω   with Y⊂X$Y\subset X$, the approximating sets can be chosen so that they contain Y∩_Ω0$Y\cap {\Omega }_0$. As a consequence, we derive a necessary and sufficient condition for a complex analytic set X to admit a Nash approximation which coincides with X along its arbitrary given subset.     

基于层次分析法的企业网络舆情危机应对评价研究

网络舆情危机应对评价是企业在新的舆论背景下研究危机应对的重点.采用定量和定性分析有机结合的层次分析法确定指标体系及权重,给出了企业网络舆情危机应对评价的步骤,并进行了评价验证.该评价体系为相关单位网络舆情危机应对评价提供一定的参考和指导.     

Microfluidic-based nanoparticle synthesis and their potential applications

A lot of substantial innovation in advancement of microfluidic field in recent years to produce nanoparticle reveals a number of distinctive characteristics, for instance, compactness, controllability, fineness in process, and stability along with minimal reaction amount. Recently, a prompt development, as well as realization in the production of nanoparticles in microfluidic environment having dimension of micro to nanometers and constituents extending from metals, semiconductors to polymers, has been made. Microfluidics technology integrates fluid mechanics for the production of nanoparticles having exclusive with homogenous sizes, shapes, and morphology, which are utilized in several bioapplications such as biosciences, drug delivery, and healthcare including food engineering. Nanoparticles are usually well-known for having fine and rough morphology because of their small dimensions including exceptional physical, biological, chemical, and optical properties. Though the orthodox procedures need huge instruments, costly autoclaves, use extra power, extraordinary heat loss, as well as take surplus time for synthesis. Additionally, this is fascinating to systematize, assimilate, in addition, to reduce traditional tools onto one platform to produce micro and nanoparticles. The synthesis of nanoparticles by microfluidics permits fast handling besides better efficacy of method utilizing the smallest components for process. Herein, we will focus on synthesis of nanoparticles by means of microfluidic devices intended for different bioapplications.     

Metal-facilitated Photocatalytic Nanohybrids: Rational Design and Promising Environmental Applications

As a promising technique to potentially address the energy crisis and environmental issues, photocatalysis has been reported widely to exhibit various outstanding behaviors in production of new fuels/chemicals and treatment of contaminants. The photocatalytic performance is extremely dependent on the used photocatalysts, so that the design and preparation of efficient photocatalysts are critically important for significantly improving the photocatalytic activity. Among various strategies, the hybridization of metal with semiconductors has recently been attracting more and more research interest owing to their expended spectral absorption, promoted transferring rate of charge carriers and Plasmon-enhanced effect. In this minireview, the metal-facilitated hybrid photocatalysts are overviewed comprehensively to first reveal unique functions of metals in improvement of photoactivity and summarize the emerging metal-involved hybrid systems. Subsequently, the synthetic methods towards hybrid photocatalysts are introduced and their practical applications are emphasized in environmental remediation including degradation of organic pollutants, conversion of harmful gases, treatment of heavy metal ions and sterilization of bacteria. At the end, the challenges for industrializing these hybrid photocatalysts are discussed carefully and future development is suggested rationally.