Encoded beads for electrochemical identification

Encoded redox beads, based on the encapsulation of different quantum dots (QD) within polystyrene microspheres, have been developed for electrochemical identification. Encoded redox rods, prepared by sequential plating of different metal tracers into the pores of a host membrane, have also been designed. By incorporating different predetermined levels of multiple metal markers, such redox-encoded particles lead to a large number of recognizable voltammetric signatures and, hence, offer great promise for covert tagging of commercial products. The resulting voltammetric signatures correlate well with the predetermined loading ratio, indicating a reproducible encapsulation process. As desired for effective authenticity testing, QD-based "identification layers" were reproducibly cast and removed from packages of commercial products to display their distinct voltammetric profiles. Factors affecting the preparation of such identification layers were optimized.     

Encoded and multiplexed surface plasmon resonance sensor platform

We present a flexible new sensor system that combines the joint advantages of (i) discretely functionalized, code-bearing, microparticles and (ii) label-free detection using grating-coupled surface plasmon resonance. This system offers the possibility of simultaneously investigating the real-time binding kinetics of a variety of molecular interactions. One single multiplexed assay could employ a wide range of immobilization chemistries, surface preparation methods, and formats. Thus, the new system offers a very high level of assay conformability to the end user, particularly when compared to fixed microarrays.     

Local-Tetra-Patterns for Face Recognition Encoded on Spatial Pyramid Matching

Face recognition is a big challenge in the research field with a lot of problems like misalignment, illumination changes, pose variations, occlusion, and expressions. Providing a single solution to solve all these problems at a time is a challenging task. We have put some effort to provide a solution to solving all these issues by introducing a face recognition model based on local tetra patterns and spatial pyramid matching. The technique is based on a procedure where the input image is passed through an algorithm that extracts local features by using spatial pyramid matching and max-pooling. Finally, the input image is recognized using a robust kernel representation method using extracted features. The qualitative and quantitative analysis of the proposed method is carried on benchmark image datasets. Experimental results showed that the proposed method performs better in terms of standard performance evaluation parameters as compared to state-of-the-art methods on AR, ORL, LFW, and FERET face recognition datasets.     

Polarization Encoded Color Image Embedded in a Dielectric Metasurface

Optical metasurfaces have shown unprecedented capabilities in the local manipulation of the light's phase, intensity, and polarization profiles, and represent a new viable technology for applications such as high‐density optical storage, holography and display. Here, a novel metasurface platform is demonstrated for simultaneously encoding color and intensity information into the wavelength‐dependent polarization profile of a light beam. Unlike typical metasurface devices in which images are encoded by phase or amplitude modulation, the color image here is multiplexed into several sets of polarization profiles, each corresponding to a distinct color, which further allows polarization modulation‐induced additive color mixing. This unique approach features the combination of wavelength selectivity and arbitrary polarization control down to a single subwavelength pixel level. The encoding approach for polarization and color may open a new avenue for novel, effective color display elements with fine control over both brightness and contrast, and may have significant impact for high‐density data storage, information security, and anticounterfeiting.     

彩色伪随机编码闪光投影系统的建模及其标定

为实现仅用一幅图象在真正的三维欧氏空间重构三维场景,尤其是动态的三维场景,系统需要对彩色伪随机编码闪光投影系统进行建模和预标定。当系统参数改变后,利用伪随机编码图案的几何约束,不需重新标定,可实现自适应重构三维场景。通过对投影仪像质的的无畸变性分析,用线性模型对投影仪成像过程进行建模,并提出一种高精度的投影系统直接标定方法,通过测出靶标上各投影编码特征点在空间的三维齐次坐标,求出内外参数实现了对投影仪的预标定。标定精度达到0.1单元格,欧氏重构结果较为理想。     

彩色伪随机编码图像角点检测方法研究

研究了基于投射彩色伪随机编码图像的三维测量技术中图像特征角点的检测问题.为了克服传统的Harris算子只能对灰度图像进行像素级定位的缺点,提出利用伪随机编码图像独特的窗口阵列唯一特性,将其扩展到彩色图像,并通过对特征点周围的像素灰度值分布做二次曲面拟合并求解其极值,实现了彩色角点的亚像素级准确定位.理论分析和实验结果均表明该方法是有效的.     

Encoded Multichromophore Response for Simultaneous Label‐Free Detection

The self‐assembly of molecularly precise nanostructures is widely expected to form the basis of future high‐speed integrated circuits, but the technologies suitable for such circuits are not well understood. In this work, DNA self‐assembly is used to create molecular logic circuits that can selectively identify specific biomolecules in solution by encoding the optical response of near‐field coupled arrangements of chromophores. The resulting circuits can detect label‐free, femtomole quantities of multiple proteins, DNA oligomers, and small fragments of RNA in solution via ensemble optical measurements. This method, which is capable of creating multiple logic‐gate–sensor pairs on a 2 × 80 × 80‐nm DNA grid, is a step toward more sophisticated nanoscale logic circuits capable of interfacing computers with biological processes.     

视觉测量中动态编码点的设计与检测

针对机器视觉动态测量中编码点的使用需求,提出了一种基于频率编码的动态编码点。在测量过程中,动态编码点按照固定的频率闪烁,将编码点的闪烁频率作为编码信息。动态编码点由静态定位区与动态编码区组成,其中,静态定位区用于对动态编码点特征圆的识别与定位,编码点的编码信息储存在动态编码区中。根据动态编码点的结构,设计了编码点的检测与解码算法,实现了动态编码点的快速检测。编码点提取实验结果表明,动态编码点编码方案简便稳定,便于布置,易于检测和识别,满足设计要求。     

Encoded Microneedle Arrays for Detection of Skin Interstitial Fluid Biomarkers

Skin interstitial fluid (ISF) is considered as an emerging source of biomarkers with physiological and medical significance. Microneedle arrays (MNs) provide a promising means for painless, noninvasive detection of these biomarkers. Here, novel MNs integrated with photonic crystal (PhC) barcodes are presented, and multiplex specific detection of ISF biomarkers is realized for the first time. The PhC barcodes‐loaded flexible MNs are simply fabricated by replicating dynamic ferrofluid‐cast micromoldings. When the prepared MNs are inserted into skin, they can enrich specific biomarkers to their probes‐decorated PhC barcodes. Thus, by adding corresponding fluorescent probes to form sandwich immunocomplexes, the relative content of the biomarkers can be read out through the fluorescence intensity of the barcodes; meanwhile, the species of these biomarkers can be clearly distinguished by the reflection peaks of the PhC barcodes. Based on the encoded MNs, their sensitivity, flexibility, and versatility of capturing and detecting three inflammatory cytokines are demonstrated in a sepsis mice model. Compared with existing MNs for ISF detection, the encoded MNs not only possess equivalent detection effects with less post‐processing and simplified procedures, but can also detect multiple biomarkers simultaneously, which makes them ideal in many clinical and biomedical detection areas.     

Integrally Encoded Systems for Recording Ionizing Radiations. Bipolar Measurements

The results of an investigation and a comparison of bipolar and unipolar recording systems, intended for determining the spatial distributions of sources of ionizing radiation, using integrally encoded measurement systems are presented. It is shown that bipolar systems have some advantage when obtaining images based on the focal-planes method.__________Translated from Izmeritel’naya Tekhnika, No. 6, pp. 58–62, June, 2005.