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Zhao Y.,Shanghai Normal University | Yao Y.,Shanghai Normal University | Xiao M.,Shanghai Normal University | Chen Y.,Shanghai Normal University | And 5 more authors.
Food Control | Year: 2013

In order to ensure the safety of infant formula powder in China, a rapid and sensitive detection method for food-borne bacteria is urgently needed. We have developed a reliable immunoassay based on nuclear magnetic resonance for the specific detection of Enterobacter sakazakii in dairy samples with biofunctionalized magnetic nanoparticles. This method is able to detect Cronobacter sakazakii in milk powder and cheese samples at 1.1 to 11MPN using the most-probable-number (MPN) assay, within an incubation period of less than 2h. Longer incubation time (>4h) or higher pH (>7) will decrease the sensitivity of this method. This method does not fit for the detection of bacteria at higher concentrations (>1100MPN). This method has great potential to becomea useful tool for the rapid detection of bacterial contaminations in food, environmental and agricultural samples. © 2013 Elsevier Ltd. Source

Li M.,Donghua University | Zhang Y.-L.,Donghua University | Du Z.-X.,Donghua University | Tang X.-Z.,Shanghai Entry Exit Inspection and Quarantine Bureau of the Peoples Republic of China
International Conference on Internet Technology and Applications, ITAP 2010 - Proceedings | Year: 2010

Based on Dabholkar's service quality model about retailing, evaluation model of outlets' service quality was established. Using Structural Equation Model (SEM), after data processing by data analysis software SPSS13.0 and model analysis software AMOS7.0, the rationality and applicability of the model was good to further analyzed. The model of Physical Aspects, Reliability, Personal Interaction, Problem Solving, Policy, which are five dimensions in the model affecting service quality, had been proved. Ultimately, corresponding marketing advices were put forward for outlets to develop their service quality. It is meaningful for outlets in China to improve their operating level. ©2010 IEEE. Source

Li X.,Shanghai University | Qiu L.,Shanghai Entry Exit Inspection and Quarantine Bureau of the Peoples Republic of China | Li Y.,Eastern Hepatobiliary Surgery Hospital | Chen X.,Shanghai University | And 2 more authors.
Biomedical Chromatography | Year: 2015

This study was designed to develop a high-performance liquid chromatographic-electrospray ionization-mass spectrometry (HPLC-ESI-MS) method for quantitative determination of residual surfactant linear alkylbenzene sulfonate (LAS) compounds on pharmaceutical rubber stoppers. An HPLC-ESI-MS method was developed for separation and determination of five LAS homologs (C10-C14) under gradient conditions using methanol and ammonium acetate as mobile phases. Hemolysis activity of residual LAS compounds was analyzed by spectrophotometry. Expression of interleukin (IL)-6 and tumor necrosis factor (TNF)-α in human umbilical vein endothelial cells (HUVECs) after LAS compound treatment was examined by enzyme-linked sorbent assay. LAS compounds were well separated and determined by the established gradient conditions. The linear range was 0.05-8 μg/mL with correlation coefficients ≥0.997. Recoveries were from 73 to 134% and the relative standard deviation was <13.7%. There was a correlation between hemolysis rate and LAS compounds concentration when it was ≥0.8 μg/cm2. LAS compounds decreased the viability of HUVECs and promoted the production of IL-6 and TNF-α. The developed analytical method was successful for quantitative determination of residual LAS compounds on pharmaceutical rubber stoppers and it is important to monitor and control the amount of LAS compounds on rubber stoppers. © 2015 John Wiley & Sons, Ltd. Source

Li X.,Shanghai Normal University | Chen Y.,Shanghai Normal University | Zhang Z.,Shanghai Normal University | Han W.,Shanghai Entry Exit Inspection and Quarantine Bureau of the Peoples Republic of China | And 5 more authors.
Journal of Chinese Institute of Food Science and Technology | Year: 2013

This paper reported a rapid detection method of Salmonella using low field nuclear magnetic resonance (NMR). The Fe3O4 magnetic nanoparticles were coated with silica to empower the nanoparticles with high dispersion and broad compatibility to biomacromolecules. The magnetic beads were modified with amino silane, which could immobilize antibody. The immune magnetic beads specifically attached to the surface of Salmonella in the enrichment. Nuclear magnetic resonance was used to obtain the value of ΔT2 to determine microorganism polluting condition. In this study, five different bacteria strains (E. coil O157, S. typhimurium, S. flexneri, S. aureus, and V. parahemolyticus) were used as control to test the specificity of this method, which performanced high specificity. Moreover, the reaction conditions were optimized in the study. The results indicated that the optimal concentration of magnetic beads was 0.14 mg/mL and the minimum level of this method was 103 cfu/mL. Source

Zhang X.,Shanghai Entry Exit Inspection and Quarantine Bureau of the Peoples Republic of China | Zou Q.,Nanjing Southeast University | Zhou Z.,Nanjing Southeast University | Wu L.,Shanghai Entry Exit Inspection and Quarantine Bureau of the Peoples Republic of China
Lecture Notes in Electrical Engineering | Year: 2011

In this paper, the isolation and the voltage division factor changes of AMN are studied when AMN is grounded via various ground wires of different impedances, which is to simulate impacts brought by poor ground conditions on in-site test results of EUT. The result shows the isolation and the voltage division factor vary with changes of frequency and the length of the ground wire for AMN. In addition, the impedance of the ground wire will seriously affect the repeatability and the accuracy of the test results. © 2011 Springer-Verlag Berlin Heidelberg. Source

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