基于铜配合物和抗体包被化学镀纳米金共固定的癌胚抗原安培免疫传感器

研制了基于抗体包被化学镀纳米金(AuNPs)和[Cu (bpy) 2 (ONO)]NO3配合物(CuL）共固定修饰玻碳电极(GCE)的安培免疫传感器,并用于血清中癌胚抗原(CEA)的检测。首先将GCE电极表面氧化形成羧基,进而键合上乙二胺。将此胺化电极浸泡在CuL和化学镀金溶液后, CuL可通过π-π堆积作用吸附到GCE表面,并在电极表面还原成30~50 nm的纳米金层（GCE|CuL/AuNPs）。将上述电极浸泡在CEA抗体(anti CEA)溶液中,利用AuNPs固定anti CEA,并通过辣根过氧化物酶(HRP)封闭剩余的AuNPs位点,由此构建了一类快速检测 CEA的无试剂安培免疫传感器（GCE|CuL-AuNPs /anti CEA-HRP）。由于HRP可以催化CuL和过氧化脲（CP）的氧化还原反应,因此该电极在CP溶液中形成催化还原电流。当该传感器在37 ℃下,含CEA的pH 6.5PBS溶液中温育30 min后,随着温育液中CEA浓度的增加,电极表面形成的免疫复合物也增加,导致CuL 对CP 的催化电流下降。电流下降百分比I%与CEA浓度在0.1~80 ng/mL 成线性关系,检测限为0.052 ng/mL（3σ）。由于采用化学镀法可以方便地在GCE表面制备纳米金膜进而包被抗体,并通过π-π堆积作用吸附CuL作为电子媒介体,故该免疫电极制备简单;采用可催化CP还原的HRP封闭AuNPs层多余位点,大大提高了电极灵敏度,有望用血清中痕量CEA分析。     

基于抗体包被纳米金和铜配合物共固定修饰电极的癌胚抗原安培免疫传感器研究

研制了基于抗体包被化学镀纳米金(AuNPs)和[Cu(bpy)2(ONO)]NO3配合物(CuL)共固定修饰玻碳电极(GCE)的安培免疫传感器,并用于血清中癌胚抗原(CEA)的检测。首先将GCE电极表面氧化形成羧基,进而键合上乙二胺。将此胺化电极浸泡在CuL和化学镀金溶液后,CuL可通过π-π堆积作用吸附到GCE表面,并在电极表面还原成30~50nm的纳米金层(GCE|CuL/AuNPs)。将上述电极浸泡在CEA抗体(anti CEA)溶液中,利用AuNPs固定anti CEA,并通过辣根过氧化物酶(HRP)封闭剩余的AuNPs位点,由此构建了一类快速检测CEA的无试剂安培免疫传感器(GCE|CuL-AuNPs/anti CEA-HRP)。其中CuL作为电子媒介体对过氧化脲(CP)有催化还原作用,而且HRP可增强这种作用。当该传感器在37℃下,含CEA的pH6.5PBS溶液中温育30min后,随着温育液中CEA浓度的增加,电极表面形成的免疫复合物也增加,导致CuL对CP的催化电流下降。电流下降百分比1%与CEA浓度在0.1~80ng/mL之间成线性关系,检测限为0.052ng/mL(3σ)。由于采用化学镀法可...     

适用于鱼肉中氯霉素检测的抗体包被金磁纳米微粒修饰安培免疫传感器研究

研制了基于氯霉素抗体包被Fe3O4/Au金磁纳米微粒(GMP)和三乙撑四胺铜(II)(CuL)共固定修饰平面热解石墨电极的安培免疫传感器(PRG|CuL / anti CAP-GMP),用于测定鱼肉中CAP含量.该免疫传感器是利用外加磁场,将anti CAP-GMP吸引到CuL修饰的PRG电极(PRG|CuL)表面制备而成.CuL对H2O2还原具有良好的电催化能力,当该传感器在含CAP样品液中温育后,CAP与电极表面的anti CAP的免疫结合物导致CuL对H2O2的催化还原电流(I)降低,电流下降值(△I)和CAP浓度成正比,可用于CAP定量测定.在25℃的pH=6.5磷酸盐缓冲液(PBS)中温育30 min,该传感器对CAP的检测线性范围为0.6~110 ng/mL,检出下限为0.092 ng/mL(3σ法).应用于鱼肉中CAP检测并与传统的液相色谱法(HPLC)比较,结果一致,其添加回收率在97%~104%之间.该免疫传感器集分离、富集为一体,电极表面可更新,检测灵敏快速,对于水产品中痕量氯霉素分析提供了一种新颖的方法.     

基于壳聚糖包埋二氧化硅-亚甲基蓝纳米复合物的电流型癌胚抗原免疫传感器的研究

合成了一种新型的SiO2-亚甲基蓝(SiO2-MB)纳米复合物.SiO2-MB纳米复合物具有不同于一般的纳米SiO2的性质,它能将MB的电子转移到电极表面,而且更重要的是减小了MB的渗漏.SiO-MB纳米复合物作为免疫传感器的媒介体使用,并采用壳聚糖(CS)包埋此复合物形成CS-SiO2-MB复合膜滴涂于洁净的玻碳电极(GCE)表面,然后在复合膜的表面固定纳米金(nano-Au)并吸附癌胚抗体(anti-CEA),制备出了性能良好的电流型免疫传感器.通过循环伏安考察了电极的电化学特性,并采用透射电子显微镜(TEM)对SiO2-MB纳米复合物的微观结构进行了表征.在最优条件下,该传感器在癌胚抗原(CEA)浓度为1～80 ng/mL范围内有良好的线性关系,检测下限为0.3 ng/mL(3倍信噪比).而且,该传感器制作简单,检测快速,稳定性较好.     

日本血吸虫抗体电化学免疫传感器研究

该文研制了一种高灵敏的基于辣根过氧化物酶(HRP)放大的电化学免疫传感器用于日本血吸虫抗体的检测.实验采用夹心法的模式,在电极表面固定了日本血吸虫抗原(SjAg),用以捕获血清中的日本血吸虫抗体(SjAb),然后再与辣根过氧化物酶(HRP)标记的羊抗兔IgG二抗形成免疫复合物.用计时安培法检测HRP酶催化H2O2还原对苯二酚底物产牛的电流,其大小与日本血吸虫抗体(SjAb)浓度在一定范围内成正比.对免疫反应的实验条件如电极表面固定抗原的浓度,HRP酶标二抗的浓度进行了优化.此外,还考察了其它蛋白质对测定结果的影响.结果表明,该方法操作简单,灵敏度高,线性范围宽,检测下限低.     

基于HRP催化过硫酸盐阴极电致化学发光的非标记型免疫传感器

基于酶催化阴极电致化学发光（ECL）构建灵敏的免疫传感器用于肿瘤标志物检测。利用过氧化氢酶（HRP）催化H2O2底物反应产生大量溶解氧,催化增强S2O82-的阴极ECL信号,构建非标记型免疫传感器。当抗原蛋白在电极表面与抗体形成免疫复合物时,屏蔽了检测液中底物与电极表面固载酶之间的接触并阻碍了电子传递,使ECL信号强度随抗原浓度增加而减小,建立ECL信号与待测物浓度之间的线性依赖关系,实现对血清中肿瘤标志物CEA的快速灵敏检测,检测限达1.04 ng/mL。     

基于Nafion-石墨烯复合物固定甲胎蛋白电化学免疫传感器的研究

该文利用Nation-石墨烯复合物和纳米金固定甲胎蛋白抗体(anti-AFP),构建了高灵敏的电化学免疫传感器.首先将石墨烯分散在Nation溶液中制得Nation-石墨烯的复合膜,并将其固定在玻碳电极(GCE)表面,通过静电吸附和共价键合作用将硫堇(Thi)和纳米金颗粒(nano-Au)依次固定到Nation-石墨烯复合膜修饰的玻碳电极表面.再通过纳米金单层吸附anti-AFP,最后用牛血清蛋白(BSA)封闭电极上的非特异性吸附位点,从而制得了甲胎蛋白免疫传感器.实验结果表明,该修饰电极对不同浓度的甲胎蛋白(AFP)有很好的响应,其线性范围为0.8～100 ng/mL,检出限为0.36 ng/mL.     

基于纳米金/硫堇修饰金电极的脱落酸安培免疫传感器的研制

提出了一种基于纳米金/硫堇修饰金电极的ABA安培免疫传感器。该传感器基于H2O2-HRP-硫堇催化波体系构建,其中硫堇为传感介质。当HRP存在时,通过加入H2O2,硫堇的还原电流大幅增加,并且电流的增加依赖于HRP活性。HRP活性又由ABA与HRP酶标抗体结合物调控,产生一个减小的催化波。用BSA封闭硫堇单分子层修饰后可能存在的活性位点以避免非特异性吸附。优化了测定条件,包括酶标抗体和硫堇的最佳比例、培育时间、缓冲液的pH值和H2O2浓度。此传感器的还原电流在ABA浓度0.5~1000ng/mL范围内呈线性下降,回归方程为y=0.0209x 17.071,相关系数为0.9922,检测限为0.2ng/mL。     

基于金-石墨烯修饰的高灵敏甲胎蛋白电化学免疫传感器

以具有大比表面积和良好生物相容性的纳米金颗粒(AuNPs)和金-石墨烯复合物(Au-Gra)为基底,成功制备了高灵敏甲胎蛋白免疫传感器。首先在金电极表面电沉积一层纳米金,接着滴涂一层具有独特电化学活性的铁氰化镍纳米粒子(NiNPs)电子媒介体,然后滴加一层Au-Gra复合膜,最后利用Au-Gra结合甲胎蛋白抗体(anti-AFP),从而制得甲胎蛋白免疫传感器。采用循环伏安法对电极性能进行了验证,结果表明该传感器有良好的电流响应性能,检测线性范围为0.1~100 ng/mL,检出限为0.03 ng/mL (S/N=3)。此传感器简单、快速、灵敏,可望用于临床诊断。     

纳米金修饰铂金电极固载白喉抗原免疫传感器的研究

该文报道了一种制作电流型白喉抗原免疫传感器的方法.用金纳米颗粒吸附白喉抗原,采用聚乙烯醇缩丁醛(PVB)为辅助固定抗原膜基质将其固定在铂金电极的表面,制成白喉抗原免疫传感器.根据抗原抗体特异性结合形成的免疫复合物使电极敏感膜有效扩散面积减小,电流减少的特性,实现对白喉抗体的定量检测.该传感器对白喉抗体检测的线性范围是2...     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.