Estimation of sample processing uncertainty for chlorpyrifos residue in cucumber

Sample processing is a very important component of uncertainty in analytical results. In order to have reliable results, the laboratory sample should be properly processed to obtain statistically homogenous matrix—before the representative test portions are withdrawn for analysis. The use of ¹⁴C-labeled compound is preferable because the analyte can be quantified without cleanup. The method is based on surface treatment of cucumber with ¹⁴C-chlorpyrifos, determination of ¹⁴C-chlorpyrifos activity in the replicate test portions of different size, and determination of the uncertainty of sample processing.     

Asymptotical synchronization for chaotic Lur’e systems using sampled-data control

This paper presents a new method for the asymptotical synchronization of two identical chaotic Lur’e systems using sampling control. The method is based on a new Lyapunov–Krasovskii functional (LKF) in the framework of an input delay method. Compared with existing works, the new LKF makes full use of the information on the nonlinear part of the system and introduces a novel term, which waives the common positive requirement of each LKF term to guarantee the positive of the whole LKF. A typical Chua’s circuit is given to verify the effectiveness of the proposed method.     

Fast and Accurate Approximation of the Full Conditional for Gamma Shape Parameters

The gamma distribution arises frequently in Bayesian models, but there is not an easy-to-use conjugate prior for the shape parameter of a gamma. This inconvenience is usually dealt with by using either Metropolis–Hastings moves, rejection sampling methods, or numerical integration. However, in models with a large number of shape parameters, these existing methods are slower or more complicated than one would like, making them burdensome in practice. It turns out that the full conditional distribution of the gamma shape parameter is well approximated by a gamma distribution, even for small sample sizes, when the prior on the shape parameter is also a gamma distribution. This article introduces a quick and easy algorithm for finding a gamma distribution that approximates the full conditional distribution of the shape parameter. We empirically demonstrate the speed and accuracy of the approximation across a wide range of conditions. If exactness is required, the approximation can be used as a proposal distribution for Metropolis–Hastings. Supplementary material for this article is available online.     

Chemical and environmental sampling: quality through accreditation, certification and industrial standards

Executive summary In the CEN/STAR Trends Analysis workshop on Sampling, initiated by request of the Nordic Innovation Centre, specially invited experts provided presentations on demands about regulation concerning sampling quality, sampling standard developments, quality assurance systems and practical experience from different sampling situations and cases. The workshop arrived at recommendations on the importance of proper sampling for environmental and product control purposes, especially to support European regulations, trade agreements and monitoring of environment. Sampling is an integrated part of the whole measurement process and should therefore be especially considered from the viewpoint of the end-user of the results. There is a need for raising quality control issues in sampling and for the establishment of a more uniformly co-ordinated European quality system for sampling. With the standard methods available, there are in principle two different ways of achieving third party assessment of the sampling protocols and procedures: accreditation of sampling organisations based upon international, national, or in-house standards and methods, and certification of individual samplers’ competences for sampling. Several activities or efforts as well as research and standardisation needs for raising the quality issues in sampling were identified and presented in a paper by the workshop.All the presentations and Workshop Proceedings are electronically available on the Nordic Innovation Centre's web site at and more specifically at     

Temperature–pressure shuffling outlier flooding method enhances the conformational sampling of proteins

Outlier flooding method (OFLOOD) is an efficient conformational sampling method developed by the authors. In the present study, to further enhance the conformational sampling efficiency, a set of parameters (temperatures and pressures) specified as inputs in the original OFLOOD were shuffled before restarting the short-time molecular dynamics (MD) simulations. Because of the diversity of these parameters, it was confirmed that the extended OFLOOD becomes superior to the original one in finding the folding pathways of Trp-cage. © 2019 Wiley Periodicals, Inc.     

重复采样试验设计的检验效能及其应用

本文探讨了单组重复采样设计及配对重复采样设计的检验效能和相应样本含量的估计 ,并在相同检验效能的条件下建立了重复采样资料 (非独立样本 )与单一测量资料 (独立样本 )间样本含量的关系式。以实例分析 ,其结果与实际相符合。     

An insight on sampling,identification, quantification and characteristics of microplastics in solid wastes

Microplastics (MPs) have attracted wide attention all over the world as a remarkable pollutant. While MPs are spreading throughout several complex environmental matrices, various experiments till date have been preliminary concentrate on aquatic ecosystems. Terrestrial sources namely solid waste-origin have remains unexplored, although they contribute largely for aquatic microplastics origin. Simultaneously, terrestrial systems under human activity, like healthcare units, are likely to be polluted by various plastic ingredients. Solid waste MPs sources primarily include sanitary landfilling, food waste, wastewater treatment end-product (sludge), tire wear, textile washing and paint failure. These microplastics caused adverse impacts on ecosystem, environment, and health. Accordingly, the present study addressed solid waste MPs’ occurrence and sources, identification, quantification, characterization, fate, and degradation pathways for developing comprehensive management strategies following the principles of circular economy. In particularly, this paper critically demonstrated solid waste MPs sources, solid waste MPs sampling followed by identification and quantification by adopting combined chemical (e.g., spectroscopy viz., Fourier transform infrared (FTIR) spectroscopy, and Raman spectroscopy), physical (e.g., microscopy such as transmission or scanning electronic microscopy, TEM or SEM) and thermal analyses. Additionally, the strengths and limitations of each analytical technique are discussed critically with practical aspect. Further, the MPs related national and international regulations or laws and their subsequent relevance to solid waste MPs management with future challenges are discussed very critically. Finally, the outcomes of the review paper will be valuable to different stakeholders for effective policy implementation.     

相干光OFDM系统中基于导频辅助的采样时钟频率偏差估计和补偿算法

基于导频辅助法,对相干光正交频分复用系统中采样时钟频率偏差进行估计和补偿,并研究了导频的插入位置对该算法补偿效果的影响,通过对五种不同的导频插入位置进行分析和比较,得到最优导频插入位置.仿真结果表明:本文算法即使在较大的频率偏移情况下也有较好的补偿效果,并且采用该方法得到的光信噪比损耗不到1dB,可以有效地降低系统成本;不同导频插入位置对算法的补偿效果会产生影响,在较小采样频率偏移范围内时,导频平均插入方式为最优.如果采样频率偏移量较大,在导频平均插入不能很好地补偿的情况下,导频应尽量插在低频位置.