National Engineering Research Center

Guangzhou, China

National Engineering Research Center

Guangzhou, China

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Fu R.,Tsinghua University | Li Q.,Tsinghua University | Zhang J.,Tsinghua University | Wang R.,Tsinghua University | And 6 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2016

Label free point mutation detection is particularly momentous in the area of biomedical research and clinical diagnosis since gene mutations naturally occur and bring about highly fatal diseases. In this paper, a label free and high sensitive approach is proposed for point mutation detection based on hyperspectral interferometry. A hybridization strategy is designed to discriminate a single-base substitution with sequence-specific DNA ligase. Double-strand structures will take place only if added oligonucleotides are perfectly paired to the probe sequence. The proposed approach takes full use of the inherent conformation of double-strand DNA molecules on the substrate and a spectrum analysis method is established to point out the sub-nanoscale thickness variation, which benefits to high sensitive mutation detection. The limit of detection reach 4pg/mm2 according to the experimental result. A lung cancer gene point mutation was demonstrated, proving the high selectivity and multiplex analysis capability of the proposed biosensor. © 2016 SPIE.


Wang S.,Shanghai University | Fu P.,Shanghai University | Liu L.,Shanghai University | Wang L.,National Engineering Research Center | And 4 more authors.
RSC Advances | Year: 2016

An integrative strategy using LC-Q/TOF-MS and LC-QqQ-MS/MS coupled with multi-variate statistical analysis of principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) was developed to screen and identify the constituents transported into the rat cerebrospinal fluid (CSF) after oral administration of Jitai tablets (JTTs). CSF samples were pretreated with cold methanol prior to liquid chromatography, and the separation was carried out on a HSS T3 column with a linear gradient elution. Mass spectra were acquired in positive ion mode for analyte identification and targeted MS/MS mode for quantification. In the S-plot of OPLS-DA, twenty-six interested ions were extracted, among which, sixteen absorbed prototype components of JTT and seven metabolites were identified in vivo. Cysteine conjugation, demethylation and glucuronidation were the major metabolic reaction types of the identified constituents. An LC-MS/MS method with targeted multiple-reaction monitoring of scopolamine, tetrahydrocoptisine, tetrahydroberineper, protopine, tetrahydropulmatine and corydaline in rat CSF was developed to validate the identification results. The concentration of the six compounds in rat CSF was in the range of 0.014-1.678 ng mL-1. In conclusion, a LC-MS based metabolomics approach can provide a rapid and sensitive method for characterizing bioactive components of JTT at micro concentration on pathological biopsy, which benefits further pharmacology and mechanism research of JTT. © The Royal Society of Chemistry 2016.


Liu Y.-F.,Beihang University | Guo W.,Beihang University | Guo W.,National Engineering Research Center | Zhang J.,Hefei University | Xu X.-Y.,Beihang University
Journal of Donghua University (English Edition) | Year: 2015

Wet clutch is an important shifting component in automatic transmission, and its properties will affect the gear shift performance. By comparing the calculated and test results, the static friction torque model was proved to be capable of describing the real pressure and torque only in the situation of high-energy engagement. Therefore, a dynamic torque model was proposed on basis of hydrodynamic properties between friction surfaces, in which the clutch engagement was divided into three phases for hydrodynamic lubrication, mixed lubrication, and mechanical contact. The proposed dynamic torque model was validated by comparing the calculated and test results. The effects of temperature, pressure, and pressure changing rate of automatic transmission fluid(ATF) on the clutch torque were analyzed. Based on these results, the clutch-to-clutch torque control during shifting in automatic transmission was optimized, and as a result, the shifting comfort was significantly improved since the problems such as the fluctuation and sudden drop of the engine rotating speed during shifting were eliminated. Copyright © 2015 by Editorial Board of Journal of Donghua University, Shanghai China.


Sun C.-H.,National Engineering Research Center | Sun C.-H.,Key Laboratory of Information Technology in Agriculture | Sun C.-H.,China Agricultural University | Li W.-Y.,National Engineering Research Center | And 7 more authors.
Computers and Electronics in Agriculture | Year: 2013

With the increased attention given to geographical labeling and the increased awareness of enterprise brands in many countries, anti-counterfeit systems for identifying the origin of agricultural products are important for limiting the production of fake goods and improving the competitiveness of agricultural products. An anti-counterfeit system for identifying the origin of agricultural products based on GPS and encrypted Chinese-sensible Code was designed. The anti-counterfeit system used the LPC1768 microprocessor of the Coretex-M3 series as its core controller, and the system was programmed with the C language. The system could collect and process the weight and location of the agricultural products, encrypt and encode the Chinese-sensible Code based on an AES (Advanced Encryption Standard) algorithm with a different cipher each time, and then print the anti-counterfeit label. The application results showed that the system runs reliably and stably, 98% anti-counterfeit labels were correctly identified and used to trace the origin of the products. Additionally, the system accomplished the task of providing precise positioning and location accuracy is about 10. m scope and unique identification information about the origin of agricultural products and achieved the aim of developing an anti-counterfeiting system. © 2013 Elsevier B.V.


Wu J.,Nanjing University | Xu Z.,Nanjing University | Zhang W.,Nanjing University | Zhang W.,National Engineering Research Center | And 6 more authors.
AIChE Journal | Year: 2010

Aminated resin (NDA-101) and oxidized resin (NDA-702) were synthesized to remove Dimethyl phthalate (DMP) from the contaminated water. The equilibrium and heat properties in the course of adsorption process were examined and compared with two commercial heterogeneous adsorbents, namely an acrylic ester resin (Amberlite XAD-7) and a coal-based granular activated carbon (AC-750). The associated equilibrium isotherms can be well fitted by Freundlich equation and the adsorption capacities for DMP followed the order: NDA-702 > NDA-101 > AC-750 > XAD-7. The surface of XAD-7 was demonstrated to be relatively homogeneous through surface energy heterogeneity analysis, offering the sole hydrogen bonding interaction. Contrarily, heterogeneous surface of oxidized resins NDA-702 and the aminated resins NDA-101 exhibited a promising adsorption capacity and affinity toward DMP probably derived by multiple hydrogen bonding, Π-Π stacking, and micropore filling interactions. © 2010 American Institute of Chemical Engineers (AIChE).


Su H.,Hohai University | Zhang N.,National Engineering Research Center | Wen Z.,Nanjing Institute of Technology | Li H.,Hohai University
Journal of Intelligent Material Systems and Structures | Year: 2016

The concrete strength has the strong influence on service safety of mass hydraulic concrete structures. The real-time identification of concrete strength is very important to ensure the pouring quality during the construction and find timely the hidden troubles in service. Based on the analysis for the mapping relationship between concrete strength and stress wave amplitude, the method is proposed to obtain indirectly the concrete strength with self-made concrete piezoelectric ceramic smart module pairs. First, according to the service condition of hydraulic concrete structure, the concrete piezoelectric ceramic smart module is designed and the process manufacturing concrete piezoelectric ceramic smart module is presented. The protecting measures of piezoelectric ceramic piece, the peripheral material constituent, and the pouring links are introduced. Second, an integrated system, which is composed of self-made concrete piezoelectric ceramic smart modules in pair as sensor and actuator, fuzzy inference system, and other auxiliary equipments, is developed to monitor indirectly concrete strength. Its working principle is studied. Finally, an experiment of hydraulic concrete strength is implemented to demonstrate the feasibility and validity of the proposed method and developed system. The concrete piezoelectric ceramic smart modules in pair are taken as sensor and actuator embedded in hydraulic concrete specimens. The wave-based analysis method is adopted to collect the stress wave amplitude data during the pouring process of concrete specimens. The fuzzy inference approach is utilized to build the mathematical model describing the relationship between concrete strength and stress wave amplitude. Based on the above mathematical model, the concrete strength can be identified indirectly. © SAGE Publications.


Li Q.,Tsinghua University | Li Q.,National Engineering Research Center | Qiu T.,Tsinghua University | Qiu T.,National Engineering Research Center | And 11 more authors.
Analyst | Year: 2012

A deep ultraviolet-visible (DUV-Vis) reflected optical fiber sensor was developed for use in a simple spectrophotometric detection system to detect the absorption of various illegal drugs at wavelengths between 180 and 800 nm. Quantitative analyses performed using the sensor revealed a high specificity and sensitivity for drug detection at a wavelength of approximately 200 nm. Using a double-absorption optical path length, extremely small sample volumes were used (32 to 160 nL), which allowed the use of minimal amounts of samples. A portable spectrophotometric system was established based on our optical fiber sensor for the on-site determination and quantitative analysis of common illegal drugs, such as 3,4-methylenedioxymethamphetamine (MDMA), ketamine hydrochloride, cocaine hydrochloride, diazepam, phenobarbital, and barbital. By analyzing the absorbance spectra, six different drugs were quantified at concentrations that ranged from 0.1 to 1000 μg mL -1 (16 pg-0.16 μg). A novel Matching Algorithm of Spectra Space (MASS) was used to accurately distinguish between each drug in a mixture. As an important supplement to traditional methods, such as mass spectrometry or chromatography, our optical fiber sensor offers rapid and low-cost on-site detection using trace amounts of sample. This rapid and accurate analytical method has wide-ranging applications in forensic science, law enforcement, and medicine. © The Royal Society of Chemistry 2012.


Wu G.,Tianjin University | Wu G.,Cranfield University | Kechavarzi C.,Cranfield University | Li X.,Tianjin University | And 6 more authors.
Chemosphere | Year: 2013

A laboratory microcosm study was carried out to assess the influence of compost amendment on the degradation and bioavailability of PAHs in contaminated soils. Three soils, contaminated with diesel, coal ash and coal tar, respectively, were amended with two composts made from contrasting feedstock (green waste and predominantly meat waste) at two different rates (250 and 750tha-1) and incubated for 8months. During this period the treatments were sampled for PAH analysis after 0, 3, 6 and 8months. Total and bioavailable fractions were obtained by sequential ultrasonic solvent extraction and hydroxypropyl-β-cyclodextrin extraction, respectively, and PAHs were identified and quantified by GC-MS. Bioavailability decrease due to sorption was only observed at the first 3months in the diesel spiked soil. After 8months, compost addition resulted in over 90% loss of total PAHs irrespective of soil types. Desorption and degradation contributed to 30% and 70%, respectively, of the PAH loss in the spiked soil, while PAH loss in the other two soils resulted from 40% enhanced desorption and 60% enhanced degradation. Compost type and application rates had little influence on PAH bioavailability, but higher PAH removal was observed at higher initial concentration during the early stage of incubation. The bioavailable fraction of PAH was inversely correlated to the number of benzene rings and the octanol-water partition coefficient. Further degradation was not likely after 8-month although over 30% of the residual PAHs were bioavailable, which highlighted the application of bioavailability concept during remediation activities. © 2012 Elsevier Ltd.


Li M.,Chinese University of Hong Kong | Cao H.,National Engineering Research Center | But P.P.-H.,Chinese University of Hong Kong | Shaw P.C.,Chinese University of Hong Kong
Journal of Systematics and Evolution | Year: 2011

Herbal medicinal materials have been used worldwide for centuries to maintain health and to treat disease. However, adulteration of herbal medicines remains a major concern of users and industry for reasons of safety and efficacy. Identification of herbal medicinal materials by DNA technology has been widely applied, sarted from the mid-1990s. In recent years, DNA barcoding of global plant species using four standard barcodes (rbcL, matK, trnH. psbA and ITS) has been a major focus in the fields of biodiversity and conservation. These DNA barcodes can also be used as reliable tools to facilitate the identification of herbal medicinal materials for the safe use of herbs, quality control, and forensic investigation. Many studies have applied these DNA barcodes for the identification of herbal medicinal species and their adulterants. The present article reviews efforts in the identification of herbal medicinal materials using the standard DNA barcodes and other DNA sequence-based markers. © 2011 Institute of Botany, Chinese Academy of Sciences.


Mao Y.,Chongqing Medical University | Fang L.,Chongqing Medical University | Ai L.,Chongqing Medical University | Li C.,National Engineering Research Center | And 4 more authors.
PLoS ONE | Year: 2014

Pancreatic cancer is one of the most malignant neoplasms originating in the digestive system. Focused ultrasound (FUS) treatment instead of the surgery operation has been used to treat Pancreatic cancer noninvasively in clinical trials. The endocrine and exocrine glands in pancreas provide the two unique functions for a person to be healthy. It is critically important to find out if the FUS treatment can still keep the normal functions of the two glands. The goal of this study is to examine and analyze changes in histopathology and serum glucose and amylase levels of the targeted in-vivo felines after the FUS treatment. Various percentage volumes of pancreas of felines were insonified. The FUS treatment (7.5 MHz of central frequency; 5 W of acoustical power; transducer f-number = 0.33; 6 s insonification time per point) effectively generated coagulative necrosis at the insonified site while leaving tissue outside the insonified site intact. It was also observed that all felines endured well with the FUS treatment; changes introduced to pancreatic tissue after up to 50% of a pancreas by volume was insonified by the FUS procedure did not affect its normal endocrine and exocrine functions. © 2014 Mao et al.

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