Analysis of ethanol in soy sauce using electronic nose for halal food certification

The purpose of this study was to analyze ethanol content in soy sauce using mass spectrometry (MS) with electronic nose (e-nose) to determine if MS e-nose can replace gas chromatographic analysis for halal certification. Gas chromatography–flame ionization detector (GC-FID), the standard method of ethanol content, was used to analyze 24 different kinds of soy sauce. Ethanol was detected from 13 soy sauce samples in the concentration range of 0.0004–1.7wt%. The MS e-nose data were analyzed by discriminant function analysis (DFA). Based on an addition method, the results were more than 96.6% accurate when the ethanol concentrations were greater than 0.5%. A high correlation between the first score of the DFA plot and the ethanol concentration was observed. Thus, mass spectrometry based on e-nose is an efficient method for determining ethanol as a primary screening tool for halal certification.     

Antioxidant activities and nutritional properties of Jeonyak prepared with beef bone stock and gelatin

The antioxidant activities and nutritional properties of Jeonyak made with beef bone stock and gelatin were investigated. Traditional Jeonyak (J1) was prepared with beef bone stock, whereas modified Jeonyak was made with gelatin and honey (J2) or with gelatin and oligosaccharides (J3). All 3 kinds of Jeonyak had antioxidant activities and J1 had the highest activity. The α-glucosidase inhibitory activity was measured to investigate the antidiabetic effect and J3 had the highest inhibitory activity of 80.47%. Glycine was the most abundant amino acid in all 3 kinds of Jeonyak. Both traditional and modified Jeonyaks have antioxidative and antidiabetic effects, suggesting that Jeonyak can be used as an effective traditional functional food.     

Synthesis of well-dispersed Ag nanoparticles on eggshell membrane for catalytic reduction of 4-nitrophenol

A novel functional bio-nanocomposite was prepared by deposition of Ag nanoparticles onto the surface of natural eggshell membrane fibers. Practically, the functional groups exposed on the fiber surface can provide locations to anchor Ag ions when immersed into metal precursor solution. The synthesized small-sized Ag nanoparticles with uniform distribution is well decorated on the surface of interwoven fibers of eggshell membrane. The effectiveness of the as-prepared AgNPs/ESM composites as a solid phase heterogeneous catalyst has been evaluated, for the first time, on the well-known 4-nitrophenol reduction to 4-aminophenol in the presence of excess borohydride. Moreover, the kinetics of the reduction reaction was investigated at different temperatures to determine the activation energy. This work provides an important example in the introduction of natural membranes for the fabrication of functional hybrid nanocomposites which could be very useful in varying fields.     

Relationship Between Embedding Depth and Residual Stress in the cBN Grain of Monolayer Brazed Abrasive Tools

The relationship between the embedding depth and the residual stress in the brazed cBN grains is analyzed experimentally in order to optimize the embedding depth of grains in the monolayer brazed abrasive tools. It is found that the residual stress is stable without remarkable gradient in the core zones of the brazed grains. However, the stress distribution gradient is rather great in the regions such as both ends of the central axis, the margin region of the central plane in the cBN grains, and the margin region of the section plane between the grains and the filler top. The maximum tensile stress in the margin zone of the brazed cBN grains has the most important influence on the mechanical property of the grains. The embedding depth is accordingly optimized at 30-40% of the total height of cBN grain.     

An isoquinoline alkaloid from the Chinese herbal plant Corydalis yanhusuo W.T. Wang inhibits P-glycoprotein and multidrug resistance-associate protein 1

Overexpression of P-glycoprotein (P-gp) and multidrug resistance-associate protein 1 (MRP1) is a major mechanism leading to multidrug resistance (MDR) of cancer cells. These transporters expel anti-cancer drugs and greatly impair therapeutic efficacy of chemotherapy. A Chinese herbal plant Yanhusuo (Corydalis yanhusuo W.T. Wang, YHS) is frequently used in functional food and traditional Chinese medicine to improve the efficacy of chemotherapy. The objective of this work was to study effects of glaucine, an alkaloid component of YHS, on P-gp and MRP1 in resistant cancer cells.The resistant cancer cell line, MCF-7/ADR and corresponding parental sensitive cells were employed to determine reversal properties of glaucine. Glaucine inhibits P-gp and MRP1-mediated efflux and activates ATPase activities of the transporters, indicating that it is a substrate and inhibits P-gp and MRP1 competitively. Furthermore, glaucine suppresses expression of ABC transporter genes. It reverses the resistance of MCF-7/ADR to adriamycin and mitoxantrone effectively.     

Gear fault identification and classification of singular value decomposition based on Hilbert-Huang transform

An improved singular value decomposition method of gear fault identification based on Hilbert-Huang transform was proposed to overcome the problem of reconstructing a feature matrix of singular value decomposition. The method includes three steps. First, the instantaneous frequency and amplitude matrices were acquired by Hilbert-Huang transform from faulted gear signals. Second, after the matrices were decomposed by singular value decomposition, the defined distances of singular value vectors and the optimal threshold of the distance for classification were calculated. Third, the fault characteristics of a gearbox were identified and classified by the threshold of the distances. The result demonstrates that the proposed method effectively identifies the gear fault and can realize an automatic gear fault diagnosis.     

Modeling and analysis of friction in end-face/inner-face circular braiding processes

Friction between yarns could greatly influence braiding processes, especially using carbon/glass fibers. However, as the points of friction are various and traveling all the time, it is quite difficult to measure the total value of frictions. To solve this problem, mathematical models have been developed to predict the friction in two braiding processes of triaxial circular braiding processes, the widely used end-face braiding process and the inner-face braiding process. To analyze the influence of the two braiding processes to the interacted friction between yarns, some definitions and initial conditions were introduced. Based on these conditions, the yarn net, which is formed during the braiding process, was divided into numerous segments. With the geometrical and force equilibrium relationships, each yarn nodes and segments were analyzed. Based on these equations and boundary conditions, the models of two braiding processes were established and solved by Matlab. A practical engineering implementation was shown to verify the validation of the model. The results shows that the inner-face braiding process of braiding process does have a better performance in eliminating the friction than the widely used end-face braiding process.     

关于软件开发的确认过程

本刊于上期发表了林华撰写的"软件开发是否需要过程确认"一文后,不少专家认为该文提出了很好的问题,值得大家探讨,又有读者投稿阐述了自己的观点与看法,希望与林华研讨交流,本刊特选登两篇,以飨读者。     

Comparison of linear and nonlinear spectral unmixing approaches: a case study with multispectral TM imagery

Spectral unmixing has been widely used by researchers in quantitative remote sensing due to the prevalence of mixed pixels in low- or middle-resolution images. In this article, six linear and nonlinear unmixing approaches – fully constrained least squares (FCLS), bilinear-Fan model (BFM), polynomial post-nonlinear model (PPNM), supervised fuzzy c-means (SFCM), Support Vector Machine (SVM), and artificial neural network (ANN) – are applied with multispectral Landsat Thematic Mapper (TM) data in order to systematically compare their performance under different scenarios. In addition, a strategy of band selection was proposed for solving the endmember variability issue. The unmixing results were analysed in terms of the overall performance, pure and mixed data set, sub-scenes with different mixture proportions by calculating the accuracy indices: root mean square error (RMSE) and the Pearson correlation coefficient (r). Nonlinear approaches can generate a closer abundance fraction map to reference, and have a higher overall accuracy than the linear approach. Nevertheless, the performance of nonlinear approaches differed dramatically with the increased proportion of mixed pixels in different study areas. SVM, SFCM, BFM, and PPNM depicted a scenario better when the proportion of mixed pixels was high, whereas ANN worked more effectively when processing large amounts of relatively pure pixels (or mixed pixels with large/extreme proportions). The linear approach, in contrast, performed more consistently for various areas. Overall, our study indicates that nonlinear approaches are more effective than the linear one, especially for a study area consisting of different small parcels. The performance of nonlinear approaches is more sensitive to the proportion change of mixed pixels in a study area. The linear approach, however, is more appropriate for a rough estimation, particularly with little prior knowledge of the study area.