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食用蔬菜能吸收和积累微塑料 期刊论文  OAI收割
科学通报, 2019, 卷号: 64, 期号: 9, 页码: 928-934
作者:  
李连祯;  周倩;  尹娜;  涂晨;  骆永明
  |  收藏  |  浏览/下载:144/0  |  提交时间:2020/06/17
微塑料  生菜  聚苯乙烯微球  吸收  积累  健康风险  microplastics  lettuce  polystyrene microbeads  uptake  accumulation  human health risk  Microplastic (MP, 100 nm-5 mm) may present an attributable risk to ecosystem and human health, and its pollution has become a global environmental concern. Despite a wealth of information on the accumulation of MPs in aquatic species, there is no information on the uptake and accumulation of MPs by higher plants. Terrestrial edible plants are directly exposed to MPs when agricultural soil was applied with organic manure, sewage sludge as fertilizer or plastic mulching. In this paper, the uptake of two sizes of polystyrene (PS) microbeads (0.2 and 1.0 mum) and then their distribution and migration in an edible plant lettuce were firstly investigated based on laboratory experiments. We used fluorescent markers to track PS microbeads in plant tissues and found fluorescence to be a sensitive and reliable detection method. Sections from untreated control lettuce showed no autofluorescence. When roots were treated with fluorescently labeled PS microbeads, the microbeads could be identified by its fluorescence. Our main study investigated the uptake of 0.2 mum beads, as few luminescence signals were observed in lettuce roots for 1.0 mum beads in our experiment. We observed that 0.2 mum fluorescent microbeads were extracellularly trapped in the root cap mucilage (which is a highly hydrated polysaccharide) and a dark green tip (which was typical of lettuce roots exposed to label PS beads) was usually visible to the naked eye. Confocal images revealed that the PS luminescence signals were mainly located in the vascular system and on the cell walls of the cortex tissue of the roots, indicated that the beads passed through the intercellular space via the apoplastic transport system. Once inside the central cylinder, the 0.2 mum PS beads were transferred from the roots to the stems and leaves via the vascular system following the transpiration stream. We also observed that the PS beads adhered to one another and self-assembled systematically into grape-like and (chain) string-like clusters in the intercellular space of the root and stem vascular tissue of lettuce plant. In contrast to the root and stem, PS beads were dispersed in the leaf tissue. Here, for the first time we provide evidence of the adherence, uptake, accumulation, and translocation of submicrometer MPs within an edible plant. Our findings highlight the previously underappreciated human exposure pathway to MPs through the consumption of contaminated crops and emphasize the need for new management strategies to control the release of MPs waste products into the terrestrial environment. Ultimately, the potential impacts of low range sized MPs on food safety of crop plants and human health need to be urgently considered.  
Temporal and spatial distribution characteristics in the natural plague foci of Chinese Mongolian gerbils based on spatial autocorrelation 期刊论文  OAI收割
INFECTIOUS DISEASES OF POVERTY, 2017, 卷号: 6, 页码: 10
作者:  
Du, Hai-Wen;  Wang, Yong;  Zhuang, Da-Fang;  Jiang, Xiao-San
  |  收藏  |  浏览/下载:40/0  |  提交时间:2019/09/25
Temporal and spatial distribution characteristics in the natural plague foci of Chinese Mongolian gerbils based on spatial autocorrelation 期刊论文  OAI收割
INFECTIOUS DISEASES OF POVERTY, 2017, 卷号: 6, 页码: 10
作者:  
Du, Hai-Wen;  Wang, Yong;  Zhuang, Da-Fang;  Jiang, Xiao-San
  |  收藏  |  浏览/下载:37/0  |  提交时间:2019/09/25
Temporal and spatial distribution characteristics in the natural plague foci of Chinese Mongolian gerbils based on spatial autocorrelation 期刊论文  OAI收割
INFECTIOUS DISEASES OF POVERTY, 2017, 卷号: 6, 页码: 10
作者:  
Du, Hai-Wen;  Wang, Yong;  Zhuang, Da-Fang
  |  收藏  |  浏览/下载:15/0  |  提交时间:2019/09/25
Image quality assessment based on complex representation of structure information (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Electrical, Information Engineering and Mechatronics, EIEM 2011, December 23, 2011 - December 25, 2011, Jiaozuo, Henan, China
作者:  
Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
Local variance and single pixel value are combined to describe image structure information using complex method in this paper in order to improve the consistency of objective image assessment result with that of subjective method. The effect of the detail structure information on the image quality was emphasized by this method accordingly. Singular value decomposition was performed on local variance distribution complex matrix. The angle between the singular value vectors of the reference image and the disturbed image was used to measure their structural similarity. Then the quality assessment process was achieved. Results from experiments show that the proposed method is better consistent with human visual system characteristics than MSE  PSNR  and SSIM. 2012 Springer-Verlag London Limited.  
Optimum design of laser encoding and decoding on laser beam-riding guidance (EI CONFERENCE) 会议论文  OAI收割
2nd International Conference on Frontiers of Manufacturing and Design Science, ICFMD 2011, December 11, 2011 - December 13, 2011, Taichung, Taiwan
作者:  
Yang L.;  Yang L.
收藏  |  浏览/下载:33/0  |  提交时间:2013/03/25
Operating principle of laser beam-riding guidance was set forth. Based on the principle of spatial frequency-encoding  experimental results demonstrated that the receiver can receive correctly the encoded signal and can decode the signal  an optimum laser encoding mode was designed  measurement for the missdistance is feasible and all the performance parameters satisfy the demand. (2012) Trans Tech Publications  which can transfer continuous laser into pulse laser that represents different position information. Then the mathematic model of deviation from target is built  Switzerland.  a modified encoding pattern was presented  which is composed of two light paths crossed 90. Azimuth information of target is given in orthogonal coordinate system and deviation from target is linearity. As well as  characteristic distribution of spatial laser field is analyzed. Corresponding decoding mode was presented  by testing in 2 kilometers outdoor  
Image quality assessment based on gradient complex matrix (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Systems and Informatics, ICSAI 2012, May 19, 2012 - May 20, 2012, Yantai, China
作者:  
Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25
Local variance based color image quality assessment method (EI CONFERENCE) 会议论文  OAI收割
2011 2nd International Conference on Advanced Measurement and Test, AMT 2011, June 24, 2011 - June 26, 2011, Nanchang, China
作者:  
Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.
收藏  |  浏览/下载:27/0  |  提交时间:2013/03/25
Analysis model of X-ray coherent scatter images (EI CONFERENCE) 会议论文  OAI收割
3rd International Conference on BioMedical Engineering and Informatics, BMEI 2010, October 16, 2010 - October 18, 2010, Yantai, China
作者:  
Liu J.;  Liu J.;  Li Y.;  Li Y.;  Li Y.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25
Earth elevation map production and high resolution sensing camera imaging analysis (EI CONFERENCE) 会议论文  OAI收割
Optoelectronic Imaging and Multimedia Technology, October 18, 2010 - October 20, 2010, Beijing, China
作者:  
Dai L.
收藏  |  浏览/下载:140/0  |  提交时间:2013/03/25
The Earth's digital elevation which impacts space camera imaging has prepared and imaging has analysed. Based on matching error that TDI CCD integral series request of the speed of image motion  statistical experimental methods-Monte Carlo method is used to calculate the distribution histogram of Earth's elevation in image motion compensated model which includes satellite attitude changes  orbital angular rate changes  latitude  longitude and the orbital inclination changes. And then  elevation information of the earth's surface from SRTM is read. Earth elevation map which produced for aerospace electronic cameras is compressed and spliced. It can get elevation data from flash according to the shooting point of latitude and longitude. If elevation data between two data  the ways of searching data uses linear interpolation. Linear interpolation can better meet the rugged mountains and hills changing requests. At last  the deviant framework and camera controller are used to test the character of deviant angle errors  TDI CCD camera simulation system with the material point corresponding to imaging point model is used to analyze the imaging's MTF and mutual correlation similarity measure  simulation system use adding cumulation which TDI CCD imaging exceeded the corresponding pixel horizontal and vertical offset to simulate camera imaging when stability of satellite attitude changes. This process is practicality. It can effectively control the camera memory space  and meet a very good precision TDI CCD camera in the request matches the speed of image motion and imaging. 2010 SPIE.