多种超分辨荧光成像技术比较和进展评述

所见即所得是生命科学研究的中心哲学,贯穿在不断认识单个分子、分子复合体、分子动态行为和整个分子网络的历程中.活的动态的分子才是有功能的,这决定了荧光显微成像在生命科学研究中成为不可替代的工具.但是当荧光成像聚焦到分子水平的时候,所见并不能给出想要得到的.这个障碍是由于受光学衍射极限的限制,荧光显微镜无法在衍射受限的空间...     

大口径光学非球面轮廓测量过程可视化研究

研究了大口径非球面光学元件表面轮廓测量过程可视化,并设计、开发了基于双向链接边表的软件系统。提出一种改进的双向链接边表数据结构完成三维模型加载方法,建立数据结构及其相关图形元作为软件的基础层。计算非球面曲面方程获得表面轮廓的数据生成图形场景节点,并自动生成曲面测量轨迹。在非接触检测平台上进行测试,对测量数据进行平滑处理,拟合出测量获得的非球面面形,完成面形精度和表面粗糙度的评价。实验结果表明,该可视化系统技术路线正确高效、稳定性好,为非球面检测数据及其综合分析仿真提供直观的可视化平台。     

Assessing G4-Binding Ligands In Vitro and in Cellulo Using Dimeric Carbocyanine Dye Displacement Assay

G-quadruplexes (G4) are the most actively studied non-canonical secondary structures formed by contiguous repeats of guanines in DNA or RNA strands. Small molecule mediated targeting of G-quadruplexes has emerged as an attractive tool for visualization and stabilization of these structures inside the cell. Limited number of DNA and RNA G4-selective assays have been reported for primary ligand screening. A combination of fluorescence spectroscopy, AFM, CD, PAGE, and confocal microscopy have been used to assess a dimeric carbocyanine dye B6,5 for screening G4-binding ligands in vitro and in cellulo. The dye B6,5 interacts with physiologically relevant DNA and RNA G4 structures, resulting in fluorescence enhancement of the molecule as an in vitro readout for G4 selectivity. Interaction of the dye with G4 is accompanied by quadruplex stabilization that extends its use in primary screening of G4 specific ligands. The molecule is cell permeable and enables visualization of quadruplex dominated cellular regions of nucleoli using confocal microscopy. The dye is displaced by quarfloxin in live cells. The dye B6,5 shows remarkable duplex to quadruplex selectivity in vitro along with ligand-like stabilization of DNA G4 structures. Cell permeability and response to RNA G4 structures project the dye with interesting theranostic potential. Our results validate that B6,5 can serve the dual purpose of visualization of DNA and RNA G4 structures and screening of G4 specific ligands, and adds to the limited number of probes with such potential.     

概念图在化学教学中应用的中外研究对比——基于CiteSpace的知识图谱可视化分析

以CiteSpace为工具,对2009-2018年10年间概念图在化学教学中应用的中外研究文献进行可视化的对比分析.研究表明:与国外研究相比,在应用范围上,国内缺少概念图在大学化学教学中应用的相关研究;在研究内容上,国内学者应加强概念图培养学生高阶思维能力及创造力的研究;从评估方式看,国内较少采用定性和定量相结合的评估...     

Digital Interferometric Measurement of Forced Convection Heat Transfer in a Miniature Rectangular Channel

Investigations have been performed on convective heat transfer in water flowing through mini-channels using the non intrusive technique of laser interferometry coupled with digital image processing. Optical glass channels, fabricated with metallic heating surfaces, were studied using a Mach-Zehnder interferometer configuration. Fringe patterns captured using a high-sensitivity CCD camera were analyzed digitally based on a calculation method developed for the liquid medium. Results of parametric studies were compared and contrasted with relevant theoretical solutions from the literature. Indication of the onset of turbulence at Reynolds numbers smaller than the conventional transition Reynolds number for large channels has also been noticed in the experimental investigation.     

Rhorix: An interface between quantum chemical topology and the 3D graphics program blender

Chemical research is assisted by the creation of visual representations that map concepts (such as atoms and bonds) to 3D objects. These concepts are rooted in chemical theory that predates routine solution of the Schrödinger equation for systems of interesting size. The method of Quantum Chemical Topology (QCT) provides an alternative, parameter‐free means to understand chemical phenomena directly from quantum mechanical principles. Representation of the topological elements of QCT has lagged behind the best tools available. Here, we describe a general abstraction (and corresponding file format) that permits the definition of mappings between topological objects and their 3D representations. Possible mappings are discussed and a canonical example is suggested, which has been implemented as a Python “Add‐On” named Rhorix for the state‐of‐the‐art 3D modeling program Blender. This allows chemists to use modern drawing tools and artists to access QCT data in a familiar context. A number of examples are discussed. © 2017 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc.     

基于SEDRIS的虚拟试验合成环境建模技术研究

为解决合成环境的统一描述和可交互问题,在分析合成环境数据表示与转换标准SEDRIS基础上,提出了基于SEDRIS的虚拟试验合成环境建模方法,针对大气、红外、电磁等3类自然环境,给出了实现环境数据表示和转换的技术途径。通过系统开发,实现了4种试验环境条件下对产品性能的验证与评估,建立的环境模型具有良好的交互性,建模方法可应用于多种试验环境的描述,为虚拟试验合成环境模型体系、标准规范和辅助工具的形成打下了基础。     

Sequential paired covariance for improved visualization of mass spectrometry imaging datasets

Untargeted analyses in mass spectrometry imaging produce hundreds of ion images representing spatial distributions of biomolecules in biological tissues. Due to the large diversity of ions detected in untargeted analyses, normalization standards are often difficult to implement to account for pixel-to-pixel variability in imaging studies. Many normalization strategies exist to account for this variability, but they largely do not improve image quality. In this study, we present a new approach for improving image quality and visualization of tissue features by application of sequential paired covariance (SPC). This approach was demonstrated using previously published tissue datasets such as rat brain and human prostate with different biomolecules like metabolites and N-linked glycans. Data transformation by SPC improved ion images resulting in increased smoothing of biological features compared with commonly used normalization approaches.     

运载火箭试验数据管理及可视化系统设计

针对现有运载火箭试验数据管理及可视化系统依赖于第三方功能插件,未实现纯浏览器端三维模型渲染及交互,系统对运行环境依赖性强、部署和维护成本高等问题,设计了基于JavaScript框架ExtJS和WebGL框架three.js的运载火箭试验数据管理及可视化系统。首先基于B/S架构设计了系统总体框架,然后针对二维图形数据传输延迟问题设计了基于Web Worker的数据读取方案,最后针对浏览器端三维模型渲染需求提出了基于VTK模型的转换算法,设计了三维模型渲染及交互方案。试验结果显示,本系统不依赖于运行环境和功能插件,能实现浏览器端二维图形和三维模型渲染及流畅交互,为兼容国产化操作系统、降低部署和维护成本创造了条件。