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近海环境中抗生素分析样品前处理技术的研究进展 期刊论文  OAI收割
色谱, 2020, 卷号: 38, 期号: 1, 页码: 95-103
作者:  
吕敏;  陈令新
  |  收藏  |  浏览/下载:109/0  |  提交时间:2020/07/08
抗生素  近海  前处理技术  综述  antibiotics  coastal  pretreatment techniques  review  The widespread and massive usage of antibiotics for the prevention and treatment of diseases in human and animals have resulted in their continuous discharge into the environment, and finally, into the coastal environment through various pathways. Accumulation of antibiotics in aquatic organisms poses a great threat to ecological and human health, especially because it facilitates the generation and spread of bacterial resistance. Given the diverse range of antibiotics with various features, as well as their presence at low concentrations in the environment, it is imperative to develop pretreatment techniques for antibiotics in various matrices. In this paper, the pretreatment methods proposed in recent decades for antibiotics in coastal water, sediment, and biota are summarized, with emphasis on commonly used methods such as solid-phase extraction, solid-liquid extraction, matrix solid-phase dispersion, and QuEChERS. Additionally, the potential factors influencing the extraction performance and clean-up efficiency are analyzed. The advantages and disadvantages of the methods and their development are finally discussed.  
Apoptosis induction and G2/M arrest of 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone from Rubia yunnanensis in human cervical cancer HeLa cells 期刊论文  OAI收割
PHARMAZIE, 2013, 卷号: 68, 期号: 4, 页码: 293-299
作者:  
Zeng, Guang-Zhi;  Fan, Jun-Ting;  Xu, Jun-Ju;  Li, Yan;  Tan, Ning-Hua
收藏  |  浏览/下载:40/0  |  提交时间:2015/05/14
2-Methyl-1,3,6-trihydroxy-9,10-anthraquinone (MTA)  one of the major components isolated from the traditional  Chinese medicine Rubia yunnanensis  exhibited inhibitory activity on the proliferation of several  human cancer cell lines. The results from an annexin V-FITC (fluoresein-5-isothiocyanate) apoptosis assay  and DNA content analysis showed that MTA exerted cytotoxicity via apoptosis induction and G2/M cell cycle  arrest in human cervical carcinoma HeLa cells. Further  MTA was found to induce apoptosis of HeLa cells  through the mitochondria-mediated pathway. It caused the translocation of Bax to the mitochondria and  release of cytochrome c into the cytosol  which caused the cleavage of caspase and poly(ADP-ribose)  polymerase and finally triggered the apoptosis. Furthermore  the p53/p21/Cdc2-cyclin B1 signaling was  found related to the G2/M arrest caused by MTA. The over-expression of p21 and down-expression of  cyclin B1 caused by MTA inactivated the Cdc2-cyclin B1 complex of G2/M checkpoint and finally caused  the G2/M arrest in HeLa cells. This study demonstrated that MTA is a potential anti-cancer component of  R. yunnanensis  a folk anti-cancer herb used in Yunnan  China.  
Weighted data fusion algorithm in the application of visual measurement network system (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Mechatronics and Control Engineering, ICMCE 2012, November 29, 2012 - November 30, 2012, Guangzhou, China
作者:  
Zhang Y.-c.;  Zhou J.
收藏  |  浏览/下载:24/0  |  提交时间:2013/03/25
Error analysis of the micro temperature control system (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Measurement, Instrumentation and Automation, ICMIA 2012, September 15, 2012 - September 16, 2012, Guangzhou, China
Han Z.; Song K.
收藏  |  浏览/下载:48/0  |  提交时间:2013/03/25
LABTM control system based on FPGA (EI CONFERENCE) 会议论文  OAI收割
2nd International Conference on Mechatronics and Applied Mechanics, ICMAM 2012, December 8, 2012 - December 9, 2012, Taiwan
作者:  
Wang Y.;  Yu P.;  Yu P.
收藏  |  浏览/下载:151/0  |  提交时间:2013/03/25
This paper presents the digital PI control method for design and simulation of a high precision limited angle brushless torque motor control system in Field Programmable Gate Array device (FPGA). The direct drive structures which are widely applied in many servo control fields. Matlab Xilinx System GeneratorR toolbox based on Fixed-Point Arithmetic is used to design the digital PI controller using DSP architecture  plot the responses of the control system and generate the VHDL source code. The control system model consists of a digital PI  a real LABTM  and a real absolute Inductosyn  encoder to rpm and position blocks. Through loading generated codes in process of the simulation that built by the digital discrete model  it is verified that the rising time of current loop is only 1.2ms  and rate loop is 8ms  overshoot is rarely 4.2%. Finally  the comprehensive positioning accuracy of system can reach up to 5 arc sec  and the rate jitter achieves 5% with the 4 arc sec accuracy absolute Inductosyn. (2013) Trans Tech Publications  Switzerland.  
A line mapping based automatic registration algorithm of infrared and visible images 会议论文  OAI收割
5th International Symposium on Photoelectronic Detection and Imaging (ISPDI) - Infrared Imaging and Applications, Beijing, June 25-27, 2013
作者:  
Ai R(艾锐);  Shi ZL(史泽林);  Xu DJ(徐德江);  Zhang CS(张程硕)
收藏  |  浏览/下载:35/0  |  提交时间:2013/12/26
There exist complex gray mapping relationships among infrared and visible images because of the different imaging mechanisms. The difficulty of infrared and visible image registration is to find a reasonable similarity definition. In this paper, we develop a novel image similarity called implicit linesegment similarity(ILS) and a registration algorithm of infrared and visible images based on ILS. Essentially, the algorithm achieves image registration by aligning the corresponding line segment features in two images. First, we extract line segment features and record their coordinate positions in one of the images, and map these line segments into the second image based on the geometric transformation model. Then we iteratively maximize the degree of similarity between the line segment features and correspondence regions in the second image to obtain the model parameters. The advantage of doing this is no need directly measuring the gray similarity between the two images. We adopt a multi-resolution analysis method to calculate the model parameters from coarse to fine on Gaussian scale space. The geometric transformation parameters are finally obtained by the improved Powell algorithm. Comparative experiments demonstrate that the proposed algorithm can effectively achieve the automatic registration for infrared and visible images, and under considerable accuracy it makes a more significant improvement on computational efficiency and anti-noise ability than previously proposed algorithms.  
Retrieval of snow depth in Northeast China using FY-3B/MWRI passive microwave remote sensing data (EI CONFERENCE) 会议论文  OAI收割
Satellite Data Compression, Communications, and Processing VIII, August 12, 2012 - August 13, 2012, San Diego, CA, United states
Ren R.; Gu L.; Chen H.; Cao J.
收藏  |  浏览/下载:136/0  |  提交时间:2013/03/25
Comparing with optical remote sensing techniques  passive remote sensing data have been proved to be effective for observing snowpack parameters such as snow depth and snow water equivalent  which can penetrate snowpack without clouds interferences. The Microwave Radiation Imager (MWRI) loaded on the Chinese FengYun-3B (FY-3B) satellite is gradually used in the global environment research through November  2011. In this paper  we proposed a snow depth retrieval algorithm to estimate snow depth in Northeast China using MWRI passive microwave remote sensing data. A decision tree method of snow identification was firstly designed to distinguish different snow cover conditions in order to eliminate other interference signals. After using the proposed decision tree method  the processing results were further used to retrieve the snow depth in Northeast China. Finally  the practical snow depth data and the MODIS data were collected for the accuracy assessment of the proposed snow depth retrieval method. The experimental results demonstrated that the RMSE of snow depth used the proposed method was approximately 3 cm in Northeast China. 2012 SPIE.  
LED display image correction based on computer simulation (EI CONFERENCE) 会议论文  OAI收割
2012 International Applied Mechanics, Mechatronics Automation Symposium, IAMMAS 2012, September 7, 2012 - September 9, 2012, Shenyang, Liaoning, China
Zheng X.-F.; Chang F.
收藏  |  浏览/下载:24/0  |  提交时间:2013/03/25
For the purposes of correcting the LED display image  a method based on computer simulation is proposed. First  the development of the LED display panel is introduced. Second  analyze the causes of the problem which image in LED display panel has serious high nonuniformity  and introduce the existed correction techniques which are used to reduce the nonuniformity of LED display image. Simultaneously  point out the ground for shortcomings of these techniques. Third  describe the principle of correction method based on computer simulation detail from two steps  which are the luminous collection and luminous copulation. Forth  describe the realization steps of this method in accordance with the third step. Finally  this method is supplied in a LED display panel  whose resolution is 640480. Experimental results show that this method is able to reduce the non-uniformity of images from 11.06% to 0.98%. (2012) Trans Tech Publications  Switzerland.  
Improved modulation method for optical module based on compensation technology (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Industrial Control and Electronics Engineering, ICICEE 2012, August 23, 2012 - August 25, 2012, Xi'an, China
Cheng P.; Yu W.-J.; Wang R.-G.; Zheng X.-F.
收藏  |  浏览/下载:21/0  |  提交时间:2013/03/25
Accuracy synthesis of a 3-RPS parallel robot based on manufacturing costs (EI CONFERENCE) 会议论文  OAI收割
31st Chinese Control Conference, CCC 2012, July 25, 2012 - July 27, 2012, Hefei, China
Yao T.-K.; Xi Z.; Feng Z.; Zhang L.-M.; Yong W.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
Pose accuracy is an important issue for parallel robot being used as mirror supporting system of telescope. One challenging topic is the accuracy synthesis which deals with the optimal design of the manufacturing and assembling tolerances of each component under the given pose accuracy. First  the error model of the 3-RPS parallel robot is built based on total derivation of the kinematic equations. And the error variable of each spherical or rotate joint can be expressed as a single boundary error parameter but not three independent position parameters. Then  the accuracy synthesis model is formulated taking the manufacturing costs as the optimization objective and the accuracy requirements as the constraint condition. Finally  the genetic algorithm is used to solve the optimization problem and a simulation example is given. The results show that the accuracy synthesis method based on manufacturing costs can satisfy the need of pose accuracy and is better for engineering application than the method based on error sensitivity. 2012 Chinese Assoc of Automati.