DNA mutation analysis based on capillary electrochromatography using colloidal poly(N-isopropylacrylamide) particles as pseudostationary phase

Poly(N-isopropylacrylamide) (PNIPAM) is an interesting class of temperature sensitive, water soluble polymer that has a lower critical solution temperature (LCST) of 32 °C. Above the LCST, PNIPAM gets phase-separated and precipitates out from water. The fascinating temperature-sensitive property of PNIPAM has led to a growing interest in diverse fields of applications. Recently, capillary electrochromatography (CEC) has gained attention due to the wide range of applications based on the use of open tubular capillaries. In this paper, the use of phase-separated PNIPAM as a pseudostationary phase for CEC is demonstrated for the detection of single nucleotide polymorphisms (SNPs). Owing to the dynamic coating, the phase-separated PNIPAM particles did not require any immobilization technique and could exist as a mobile stationary phase in the open tubular capillary. The heteroduplex analyses of mutation samples could be successfully performed based on the phase-separated PNIPAM particles in the constructed CEC system. The CEC system, based on PNIPAM particles capable of having a narrow size distribution, shows great potential as an alternative to conventional DNA mutation systems.     

Synthesis and inclusion capability of a β-cyclodextrin-tetrathiafulvalene derivative

The synthesis of 4,5-ethylenedithio-4′-[6-deoxy-β-cyclodextrin-6-yl-aminocarbonyl]-tetrathiafulvalene 3 is reported. Dominantly, the structure of 3 has been established on the basis of mass spectrometry, ROESY and ¹H NMR spectra, combined with a theoretical MM3 study, indicating an ‘open-cavity structure’. The sensing ability of 3 and the formation constant of the complex [(3)-(1-adamantanol)] have been evaluated experimentally by UV-vis spectroscopy and theoretically by the MM3 docking procedure method.     

Capillary electrochromatography of amino acids with a protein-bonded porous-layer open-tubular column

A protein-bonded porous-layer open-tubular (PLOT) column has been synthesized and applied to the separation of amino acids by CEC. The porous layer was coated on the capillary inner wall by in situ polymerization of 2-hydroxyethyl methacrylate and 2-vinyl-4,4-dimethylazlactone in the presence of 1-decanol as a porogen inside a fused-silica capillary silanized with gamma-methacryloxypropryltrimethoxysilane. The azlactone functionalities at the surface of the porous polymeric support layer were allowed to react with BSA to yield a protein-bonded PLOT column. This porous layer was characterized by scanning electron microscopy and its thickness was about 1 microm. CEC on this column gave enhanced resolution of three amino acids (histidine, phenylalanine, and tryptophan), and baseline separation was achieved with 20 mM phosphate buffer, pH 8.0.     

Temporal variation of velocity components in a turbulent open channel flow: Identification of fractal dimensions

Fractals are objects which have similar appearances when viewed at different scales. Such objects have details at arbitrarily small scales, making them too complex to be represented by Euclidian space; hence, they are assigned a non-integer dimension. Some natural phenomena have been modeled as fractals with success; examples include geologic deposits, topographic surfaces and seismic activities. In particular, time series have been represented as a curve with fractal dimensions between one and two. There are different ways to define fractal dimension, most being equivalent in the continuous domain. However, when applied in practice to discrete data sets, different ways lead to different results. In this study, three methods for estimating fractal dimension are described and two standard algorithms, Hurst’s rescaled range analysis and box-counting method (BC), are compared with the recently introduced variation method (VM). It was confirmed that the last method offers a superior efficiency and accuracy, and hence may be recommended for fractal dimension calculations for time series data. All methods were applied to the measured temporal variation of velocity components in turbulent flows in an open channel in Shiraz University laboratory. The analyses were applied to 2500 measurements at different Reynold’s numbers and it was concluded that a certain degree of randomness may be associated with the velocity in all directions which is a unique character of the flow independent of the Reynold’s number. Results also suggest that the rigid lateral confinement of flow to the fixed channel width allows for designation of a more-or-less constant fractal dimension for the spanwise velocity component. On the contrary, in vertical and streamwise directions more freedom of movements for fluid particles sets more room for variation in fractal dimension at different Reynold’s numbers.     

Mechanical quadrature methods and their splitting extrapolations for boundary integral equations of first kind on open arcs

This paper presents the mechanical quadrature methods (MQMs) for solving boundary integral equations (BIEs) of the first kind on open arcs. The spectral condition number of MQMs is only O(h⁻¹), where h is the maximal mesh width. The errors of MQMs have multivariate asymptotic expansions, accompanied with for all mesh widths h_i. Hence, once discrete equations with coarse meshes are solved in parallel, the accuracy order of numerical approximations can be greatly improved by splitting extrapolation algorithms (SEAs). Moreover, a posteriori asymptotic error estimates are derived, which can be used to formulate self-adaptive algorithms. Numerical examples are also provided to support our algorithms and analysis. Furthermore, compared with the existing algorithms, such as Galerkin and collocation methods, the accuracy order of the MQMs is higher, and the discrete matrix entries are explicit, to prove that the MQMs in this paper are more promising and beneficial to practical applications.     

Maximum or minimum entropy generation for open systems?

Entropy generation is analysed and obtained from the entropy balance for open systems, considering the lifetime of the natural real process. The Lagrangian approach is discussed in order to develop an analytical method to obtain the stationary states of the open irreversible systems. The stationary conditions of the open systems are obtained in relation to the entropy generation and its maximum principle. An analysis of both minimum and maximum entropy generation is proposed, suggesting that they are two different viewpoints of the same aspect: the first is related to the system, while the second is related to the interaction between the system and the environment.     

不完备识别框架下的证据组合方法

证据理论应用中经常面临识别框架不完备问题。本文引入证据框架概念,把识别框架分为已知和未知两个部分,提出一种在识别框架不完备条件下表示和组合证据的开放识别框架方法。该方法能明确区分识别框架不完备与证据冲突两个不同概念,并合理解决了对未知命题集合的基本概率赋值问题,从而克服了D-S理论以及Smets的开放世界假设方法在处理不完备识别框架时存在的不足。     

费米型级联运动方程的绝热截断方案

研究开放量子系统的量子耗散动力学对于理解许多新奇量子现象背后的机制和实现量子器件的精确量子态控制具有重要意义. 级联运动方程方法已成为研究这类量子耗散动力学最常用的数值方法之一. 然而,在处理强电子关联系统时,准确描述强关联效应需要高的级联截断层数. 这导致级联运动方程方法需要耗费大量物理内存和计算时间. 为了解决该问题,将具有最快耗散速率的耗散模式与其他较慢的耗散模式分离,提出了一种级联运动方程的绝热截断方案. 在单杂质安德森模型上进行的数值测试表明,与传统的方案相比,该截断方案显著地降低了级联运动方程收敛需要的截断层数. 此外,该截断方案缓解了长时间耗散动力学中的数值不稳定性.     

Electrochemical Methods for Assessment of Polytrauma Outcomes

In this work we used electrochemical methods, open circuit potential (OCP) measurement with platinum electrode, and cyclic voltammetry (CV) in blood serum to assess redox states in patients with polytrauma (n=56) that allow to evaluate probability of survival early on, and therefore have the potential to improve therapy outcomes. Electrochemical assessment of redox states in sera samples correlated with traditional methods of prooxidant/antioxidant balance quantification. OCP and quantity of electricity passed (Q), calculated from CVs, were significantly different between the survivors and non-survivors. Patients with Q>22 μC (day 1) and OCP>34 mV (day 3) had low chance of survival.     

In-situ and one-step preparation of protein film in capillary column for open tubular capillary electrochromatography enantioseparation

In this wo rk,the phase-transitioned BSA(PTB) film using the mild and fast fabrication process adhered to the capillary inner wall uniformly,and the fabricated PTB film-coated capillary column was applied to realize open tubular capillary electrochromatography(OT-CEC) enantioseparation.The enantioseparation ability of PTB film-coated capillary was evaluated with eight pairs of chiral analytes including drugs and neurotransmitters,all achieving good resolution and symmetrical peak shape.For three consecutive runs,the relative standard deviations(RSD) of migration time for intra-day,inter-day,and column-tocolumn repeatability were in the range of 0.3%-3.5%,0.2%-4.9% and 2.1%-7.7%,respectively.Moreover,the PTB film-coated capillary column ran continuously over 300 times with high separation efficiency.Therefore,the coating method based on BSA self-assembly supramolecular film can be extended to the preparation of other proteinaceous capillary columns.