丙型肝炎负链RNA的检测及意义

检测HCV（－）RNA是了解HCV复制的有效手段。本研究采用HCV负链RNA检测法检查5例慢性活动性丙型肝炎病人的肝组织及10例慢性活动性肝炎病人的血浆及淋巴－单核细胞。HCV负链RNA在前者均被检出，但在后者未被检出。将一份HCV负链RNA阳性的肝组织提取液作10－2稀释后仍可测得阳性结果，说明肝脏为HCV复制的主要器官；该方法可用于疑难病人肝穿刺标本的检测及其它研究。     

基于DNA计算自组装模型的Diffie-Hellman算法破译(英文)

DNA自组装计算模型是近年来引人关注的计算模型,已有基于自组装模型的二进制加法、乘法以及有限域中的加法和乘法的讨论．文中利用DNA自组装模型设计的模乘系统,实现了素数P的本原根g连续乘方后模p的数的排列,从而可以在线性时间内求解离散对数,为破译Diffie—Hellman密钥交换算法提供了新的生物方法．该模乘系统使用了Θ（p）种自组装类型,组装的时间复杂度为Θ（p-1）．系统最后组装结果提取出报告链后,经过PCR和凝胶电泳读取离散对数结果．该模型扩展了DNA自组装计算模型的应用,为求取离散对数提供了新思路．     

Enhancement of thermal uniformity for a microthermal cycler and its application for polymerase chain reaction

Thermal uniformity is essentially important for micro reactors which require precise control of critical reaction temperatures. Accordingly, we report a new approach to increase the temperature uniformity inside a microthermal cycler, especially for polymerase chain reaction (PCR). It enhances the thermal uniformity in the reaction region of a PCR chip by using new array-type microheaters with active compensation (AC) units. With this approach, the edges of the microthermal cyclers which commonly have significant temperature gradients can be compensated. Significantly, the array-type microheaters provide higher uniformity than conventional block-type microheaters. Besides, experimental data from infrared (IR) images show that the percentages of the uniformity area with a thermal variation of less than 1 °C are 63.6%, 96.6% and 79.6% for three PCR operating temperatures (94, 57 and 72 °C, respectively) for the new microheaters. These values are significantly better than the conventional block-type microheaters. Finally, the performance of this proposed microthermal cycler is successfully demonstrated by amplifying a detection gene associated with Streptococcus Pneumoniae (S. Pneumoniae). The PCR efficiency of the new microthermal cycler is statistically higher than the block-type microheaters. Therefore, the proposed microthermal cycler is suitable for DNA amplification which requires a high temperature uniformity and is crucial for micro reactors with critical thermal constraints.     

PCR温度模糊PID控制器的设计及仿真

根据PCR对温度控制的要求设计出一种模糊PID控制器,采用误差和误差变化率作为模糊PID控制器的输入,PID参数作为模糊PID控制器的输出,并使用一组模糊规则实现对PID参数的在线优化调节.通过使用Simulink图形化工具平台对模糊PID控制器和传统的PID控制器进行建模和仿真.结果表明,与传统PID控制器相比,模糊PID控制器性能优良,使系统响应速度加快,超调减小.     

Extraction of genomic DNA and detection of single nucleotide polymorphism genotyping utilizing an integrated magnetic bead-based microfluidic platform

This study presents a new magnetic bead-based microfluidic platform, which integrates three major modules for rapid leukocytes purification, genomic DNA (gDNA) extraction and fast analysis of genetic gene. By utilizing microfluidic technologies and magnetic beads conjugated with CD_15/45 antibodies, leukocytes in a human whole blood sample can be first purified and concentrated, followed by extraction of gDNA utilizing surface-charge switchable, DNA-specific, magnetic beads in the lysis solution. Then, specific genes associated with genetic diseases can be amplified by an on-chip polymerase chain reaction (PCR) process automatically. The whole pretreatment process including the leukocytes purification and gDNA extraction can be performed in an automatic fashion with the incorporation of the built bio-separators consisting of microcoils array within less than 20 min. The detection of single nucleotide polymorphism (SNP) genotyping of methylenetetra-hydrofolate reductase (MTHFR) C677T region associated with an increased risk of genetic diseases was further performed to demonstrate the capability of the proposed system. The extracted gDNA can be transported into a micro PCR chamber for on-chip fast nucleic acid amplification of detection genes with minimum human intervention. Hence, the developed system may provide a powerful automated platform for pretreatment of human leukocytes, gDNA extraction and fast analysis of genetic gene.     

基于比例冲突再分配理论的目标识别应用研究

目前证据推理理论算法的改进仍然是热门的方向,其应用也越来越广,因此主要介绍了当前证据推理理论的两种最新的改进思想--最新的DSmT理论以及比例冲突再分配(PCR)方法;归纳总结了证据理论的主要应用及其在应用中的关键问题之--基本置信指派的主要构造方法;最后利用人工神经网络训练数据的方法构造基本置信指派,对比例冲突再分配(PCR5)方法在序列图像目标识别中的应用进行了仿真分析,仿真实验结果表明该算法可以有效地提高序列图像目标识别的准确性.     

汽油辛烷值NIR数据处理与建模仿真

随着当今计算机与各类程序软件的开发使用,化学计量学不断发展,人们可以在近红外光谱区内采集大量的数据,并使用各种有效的统计方法,把近红外光谱技术应用于定性与定量.近红外光谱为分子振动光谱的倍频和组合频谱带,主要是对含氢基团的吸收,包含有绝大多数类型有机物的组成与分子结构的丰富信息.原理是基于不同的基团或同一基团在不同化学...     

Nondestructive Brix Evaluation of Apples of Different Origin Using Near Infrared (NIR) Filter Based Reflectance Spectroscopy

Abstract

A filter based near infrared (NIR) technique to evaluate Brix value, in a non destructive way, of Indian apples, along with apples from other countries, has been investigated here. Reflectance characteristics at ten NIR wavelengths were recorded by in-house developed probe for five Indian varieties and four imported varieties. A separate calibration and validation set for each variety was formed. Brix values of the calibration and validation sets of apples were evaluated with a refractometer from Bellingham and Stanley, Model 840. Principal component regression was used to generate calibration and prediction of Brix for the validation set. It was found that Brix values of all varieties of apples can be predicted with a standard error of prediction, 0.7322–1.7809, while root mean square error is also in the same range. It was further noticed that reduction in data recording wavelength leads to an increase in SEP and RMSE.     

PCR-核酸薄膜层析法检测创伤弧菌

采用自行建立和优化的PCR-核酸薄膜层析检测体系,对创伤弧菌(Vibriovulnificus)进行检测。采用创伤弧菌的vvhA基因为目的片段设计特异性引物,建成可快速检测创伤弧菌的PCR-核酸薄膜层析检测法,并进行了特异性和灵敏度试验。结果表明,所建立起的检测法灵敏度为3.6×102 cfu·mL-1,比PCR-琼脂糖凝胶电泳检测方法高一个数量级。创伤弧菌的PCR-核酸薄膜层析检测方法具有较高灵敏度和良好特异性,操作简单,检测速度快,同时又保护了操作人员的身体健康,具有广阔的推广前景。