Resolution limit for DNA barcodes in the Odijk regime

We develop an approximation for the probability of optically resolving two fluorescent labels on the backbone of a DNA molecule confined in a nanochannel in the Odijk regime as a function of the fluorescence wavelength, channel size, and the properties of the DNA (persistence length and effective width). The theoretical predictions agree well with equivalent data produced by Monte Carlo simulations of a touching wormlike bead model of DNA in a high ionic strength buffer. Although the theory is only strictly valid in the limit where the effective width of the nanochannel is small compared with the persistence length of the DNA, simulations indicate that the theoretical predictions are reasonably accurate for channel widths up to two-thirds of the persistence length. Our results quantify the conjecture that DNA barcoding has kilobase pair resolution-provided the nanochannel lies in the Odijk regime.     

A method for the integer-order approximation of fractional-order systems

A procedure for approximating fractional-order systems by means of integer-order state-space models is presented. It is based on the rational approximation of fractional-order operators suggested by Oustaloup. First, a matrix differential equation is obtained from the original fractional-order representation. Then, this equation is realized in a state-space form that has a sparse block-companion structure. The dimension of the resulting integer-order model can be reduced using an efficient algorithm for rational L₂ approximation. Two numerical examples are worked out to show the performance of the suggested technique.     

Evaluation of Quality of DNA Extracted from Buccal Swabs for Microarray Based Genotyping

Buccal cell usage has been shown by many to be a cost effective and safe method to isolate DNA for various biological experiments especially large epidemiological studies (Garcia-Closas et al. Cancer Epidemiol Biomarkers Prev 10:687–696, 2001). Non-invasive DNA collection methods are preferred over phlebotomy in order to increase study participation and compliance in research centers and for sick patients in hospital settings. There have been conflicting reports about the methodology and results obtained from using buccal DNA. It is not very clear if phlebotomy can be confidently replaced by buccal cell DNA. It is often left for the user to take an intelligent decision. To address this issue, we compared the performance of buccal and blood DNA from same subjects in a genotyping experiment and this paper reports the results. Cotton swab derived buccal cells were scraped from the inner side of cheeks from 16 subjects, and blood was also drawn from the same 16 subjects participating in a genotypic association study of a lipid disease. The DNA quality was assessed by resolving on agarose gels, checking purity (A260/A280) and finally by microarray hybridization. This study showed that DNA degradation affects the total yield and performance of the buccal DNA when compared to the blood DNA in microarray based genotyping. Genotyping results can be seriously compromised if care is not taken to check the quality and yields of such specimens.     

Patent regime and the geography of cumulative innovation

The localization effect of cumulative innovation was strengthening in the past few decades, a puzzling trend given the decreasing cost of knowledge transmission. To unravel this puzzle, we attend to patent regime and propose a legal perspective. We illustrate with a stylized model that a pro-patent regime re-distributes profits from later innovators to initial patent owners, which discourages distant followers with higher learning and licensing costs and therefore leads to stronger localization of cumulative innovation. We test the model predictions by exploiting an unexpected pro-patent regime change—the creation of the Court of Appeals for the Federal Circuit. We find that follow-on innovations became more localized after patents were strengthened in litigation, especially in regions that experienced a greater increase in patent enforceability. A series of robustness tests and cross-sectional analyses strongly support this finding. Interestingly, we find that scientific knowledge diffusion, which was unaffected by patent regime, became less localized during the same period. Our paper shows that patent regime can shape the geography of cumulative innovation, which has profound implications for firm strategies and policymaking.     

Interval approximation method for stability analysis of time-delay systems

This paper studies the stability analysis of linear systems with time-varying delay, which is supposed to be the trigonometric form. By utilizing the characteristics between time-varying delay and its derivative, a novel interval approximation method is proposed, which provides the new allowable delay sets. Then making use of Wirtinger inequality, reciprocally convex inequality and the looped Lyapunov–Krasovskii functionals, the stability criteria with less conservatism are obtained. Finally, two examples are used to show the effectiveness and efficiency of the stability criteria.     

Towards alternative trajectories? Reconfigurations in the Dutch electricity regime

In the early 2000s Dutch electricity companies are increasingly investing in technologies that enable them to replace coal with biomass. Replacing large amounts of coal (up to 40%) requires the companies to invest in technological trajectories alternative to the ones they have supported over the past decades. This paper aims to understand why these incumbent firms in the Dutch electricity regime are developing alternatives. The second aim of the paper is to provide a way for assessing the potential of innovations. The paper does so by bringing together insights from literature on (socio-) technical regimes and insights from literature on technological and market niches (strategic niche management). The main conclusion is that both niche processes (at the level of experimenting with alternatives) and changes in the incumbent regime are necessary for understanding the innovation journey of a new technology. A two-by-two matrix is developed that can be used for both analysis and governance purposes.     

Boundary conditions for traceability in food supply chains using blockchain technology

Traceability of ingredients in food supply chains has become paramount in a world in which markets become global, heterogeneous, and complex and in which consumers expect a high level of quality. The food supply chain consists of many organizations having different interests and are often reluctant to share traceability information with each other. Blockchain has been advocated for improving traceability by providing trust. Yet, practice proved to be more stubborn. The goal of this paper is to identify boundary conditions for sharing assurance information to improve traceability. Four cases in the food supply chain have been investigated using a template analysis of 16 interviews. Eighteen boundary conditions categorized in business, regulation, quality and traceability categories have been identified. Some boundary conditions were found in all supply chains, whereas others were found to be supply chain specific. Standardization of traceability processes and interfaces, having a joint platform and independent governance were found to be key boundary conditions before blockchain can be used. Our findings imply that supply chain systems have first to be modified and organizational measures need to be taken to fulfill the boundary conditions, before blockchain can be used successfully.     

组合评价和复合评价模型在学术期刊评价优越性的实证研究

[目的/意义] 由于传统的单一评价方法弊端愈加明显,笔者将通过实证研究证明组合评价及复合评价模型在学术期刊评价中相对于单一评价模型的优越性,为学术期刊评价提供更合理的评价视角。[方法/过程] 单一评价方法是选择运用熵值法、因子分析法和TOPSIS法对学术期刊进行学术影响力评价,提出的组合评价模型原理是通过对这3种单一评价方法的结果进行Kendall检验,在具有显著性一致性的基础上建立模糊Borda组合评价模型进行组合评价,提出的复合评价模型的原理是通过熵值法的差异系数对因子分析的主因子方差贡献率和因子得分系数的修正,确定各指标的权重、构造加权规范矩阵,运用TOPSIS法进行综合评价。[结果/结论] 实证研究表明,组合评价模型和复合评价模型与单一评价模型评价结果一致性较好,且组合评价模型和复合评价模型具有更好的区分度,相对于单一评价具有一定的优越性。     

嵌入全球价值链的发展中国家企业升级途径研究

介绍了全球价值链理论形成历程，论述了合作升级与进入细分市场这两种升级途径，并总结了嵌入全球价值链的发展中国家企业的升级阻碍与跨越途径。     

生态工业园区工业链与自然生态系统食物链的比较

为了更好地模拟自然生态系统建立一种工业平衡体系，在生态工业园区内实现物质循环，分析了自然生态系统食物链与生态工业园区工业链的形成与特点，并从功能、稳定性、共生关系及运行规律等方面作了比较，指出生态园区内的工业链接不但服从自然生态规律，同时也受市场经济规律的制约，人的主观能动性起着十分重要的作用。强调了必须尊重自然规律，同时要注意发挥人的智能资源。     

我国生态工业园生态产业链构建模式分析

生态产业链是生态工业园建设的基础和关键。生态产业链以促进副产物和废物的交换、能量和废水的梯级利用为目的,是产业的生态集聚。我国生态工业园建设时间不长,但已初步形成了不同类型的生态产业链构建模式。通过对我国生态工业园生态产业链构建模式的分析,旨在总结一些基本经验和特色,以为我国生态工业园的建设和发展提供参考。     

图书馆电子服务质量评价指标体系构建

在调研国内外图书馆服务质量评价相关理论和实践的基础上,结合我国图书馆电子服务的现状,提出适合我国图书馆电子服务质量评价的指标体系,并对其进行了信度和效度的检验.     

高价值专利评估问题的对策研究

我国经济已由高速增长阶段转向高质量发展阶段,高质量发展需要高价值专利保驾护航。高价值专利评估是推动高价值专利转化为现实生产力的重要环节。为有效评估高价值专利,首先对高价值专利的内涵进行了界定,其次在分析和评估现有专利价值评估方法基础上,以300件中国专利奖获奖专利为研究对象,从技术因素、法律因素、经济因素、市场因素等四个层面,挖掘高价值专利的典型性特征,构建专利价值评估指标体系和评估模型。通过验证发现,该模型准确性较高、可测性较好、实用性较强,能够为加快推进高价值专利评估工作,促进高价值培育和转移转化提供借鉴与参考。最后针对高价值专利评估问题,就健全评估体系、增强评估意识与能力、打造评估服务平台等提出了对策建议。     

技术体制对FDI溢出效应的影响:基于中国制造业的计量分析

本文从技术体制这个新的视角,分析了影响FDI行业内溢出效应以及FDI技术扩散的因素。基于对我国28个制造行业1999年到2002年面板数据的计量统计分析,得到结论:对于FDI总的溢出效应,行业技术机会越少、知识基础越倾向于应用科学、行业的技术轨道流动性越弱,FDI溢出效应越容易发挥;当地企业的吸收能力对FDI溢出具有明显的促进作用;创新独占性和外部知识可获得性对FDI溢出效应的影响在本文的统计结果中并不显著。而技术体制对FDI技术扩散的作用则略有不同:技术机会、创新独占性和技术轨道流动性的反向作用在统计结果中十分显著,其他技术体制因素对FDI技术扩散的影响在本文的统计分析中没有得到体现。这一结论对我国的引资和我国本土企业的技术追赶具有重要意义。     

大豆中粗蛋白质含量不确定度的评估

通过对凯氏定氮仪测定大豆中粗蛋白质含量的检验过程进行分析,找出影响测量不确定度的因素,对各个不确定度分量进行评估和计算合成,并最终给出样品中粗蛋白质含量的合成标准不确定度及扩展不确定度。     

FDP胶囊中磷酸果糖含量的测定不确定度评定

对FDP胶囊中磷酸果糖含量测定不确定度进行了评定,分析了测量不确定度来源及建立数学模型,对各测量不确定度分量进行了评定,通过合成标准不确定度给出扩展不确定度.     

Evaluation of Oxidative Stress and DNA Damage in Benign Prostatic Hyperplasia Patients and Comparison with Controls

In the present study, oxidative stress and lymphocytic DNA damage in both pre-op and post-op benign prostrate hyperplasia (BPH) patients with age >50 years was evaluated and compared with normal healthy subjects (controls- without any evidence of disease) of the same sex and age group. From December 2007 to November 2009, oxidative stress in 45 BPH patients were evaluated both before (pre-op patients) and after 7 days of surgery (post-op patients) in terms of measurements of plasma levels of (1) various anti-oxidative enzymes, (2) non-enzymatic antioxidants and (3) malondialdehyde which is a product of lipid peroxidation. The lymphocyte DNA damage was also evaluated by single cell alkaline gel electrophoresis in terms of tail length migration in these patients. These values were compared with their respective control subjects of similar sex and age group. The activities of antioxidant enzymes and the levels of antioxidant, reduced glutathione were found significantly decreased (p < 0.05) in serum samples of pre-operative group of BPH patients as compared to the controls. These altered parameters increased significantly (p < 0.05) and returned to their near normal control values, but not up to baseline values, in post operative patients i.e. after the cancer load was decreased by surgery. Lymphocytic DNA damage was found to be significantly increased in pre-op group as compared to controls and was reduced after surgery in post-op group. The present study therefore, shows significantly increased levels of oxidative stress and DNA damage in BPH patients which were reduced after removal of tumour load. Thus oxidative damage plays an important role in prostate tumourogenesis and timely management of oxidative stress can be of importance in preventing the occurrence of BPH.