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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

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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.

A method to estimate the neutral atmospheric density near the ionospheric main peak of Mars 期刊论文 OAI收割
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, 2016, 卷号: 121, 期号: 4, 页码: 3464-3475
作者: Zou, Hong; Ye, Yu Guang; Wang, Jin Song; Nielsen, Erling; Cui, Jun

收藏 | 浏览/下载：27/0 | 提交时间：2016/10/27

The neutral densities at 130 km can be derived fromtheMGS/RS measurements with our method The derived neutral densities can be used to verify or calibrate the Martian atmospheric model The method can be applied to other radio occultation measurements such as MEX/RS measurements

The state of the art for liquid crystal adaptive optics in astronomical applications (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China
作者: Liu Y.; Liu Y.; Xuan L.; Liu Y.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

In this paper we summarize the researches of liquid crystal (LC) adaptive optics(AO) in astronomical applications. Dual frequency and nematic LC materials were reported to be used in astronomical observations. However nematic LC with its simple producing and driving method and multi-gray-level is promising in the application. We have investigated the nematic LC AO system and promoted its application for nearly ten years. Here we reported our newest nematic LC AO system with bandwidth result of 3dB is 54.4 Hz 0dB bandwidth is 79.1Hz. 2012 IEEE.

Research on soybean security of China based on system dynamics (EI CONFERENCE) 会议论文 OAI收割
31st Chinese Control Conference, CCC 2012, July 25, 2012 - July 27, 2012, Hefei, China
作者: Gao M.-H.

收藏 | 浏览/下载：25/0 | 提交时间：2013/03/25

Based on considerations of soybean production imports and exports trade processing and consumption we study the soybean industry of China with the method of system dynamics. Firstly we build the SD model of soybean industry. Secondly we optimize soybean security policy simulation dynamic model and simulate the model based on our country specific situation. At last on the basis of the simulation results we analyze current domestic soybean industry security situation and provide a method to make suggestions for soybean security policy. 2012 Chinese Assoc of Automati.

Space camera dynamic image quality measurement and evaluation (EI CONFERENCE) 会议论文 OAI收割
3rd International Conference on Measuring Technology and Mechatronics Automation, ICMTMA 2011, January 6, 2011 - January 7, 2011, Shanghai, China
作者: Zhang X.; Zhang X.; Zhang X.

收藏 | 浏览/下载：21/0 | 提交时间：2013/03/25

By using analysis of the infinity image of the space camera we intend to obtain the curve of the dynamic modulation transfer function. We extract the pixel gray values at the image edge which distribute as a knife-edge function and make differential calculation and Fourier transformation of it and then we can obtain the dynamic MTF curve of the optical system. The value of the curve at the Nyquist frequency is the most important parameter that reflects the image quality. We add push-scanning imaging and environmental effects to the static MTF of space camera and compare the MTF value with the dynamic MTF at Nyquist frequency. The comparison result can help us verify the accuracy of the calculating results and the feasibility of our method. (2011) Trans Tech Publications.

Rotation and scaling invariant feature lines for image matching (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011, August 19, 2011 - August 22, 2011, Jilin, China
作者: Wang Y.; Wang Y.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

Image matching has been one of the most fundamental issues computer vision over the decades. In this paper we propose a novel method based on making use of feature lines in order to achieve more robust image matching. The feature lines have the properties of rotation and scaling invariance coined RIFLT(Rotation invariant feature line transform). Experimental results demonstrate the effectiveness and efficiency of the proposed method. Compare with the famous powerful algorithm Scale Invariant Feature Transform(SIFT) the proposed method is more insensitive to noise. And for certain sequence of images which contain clear lines the proposed method is more efficiency. Using the feature lines obtained by our method it is possible to matching two scene images with different rotation angles scale and light distort. 2011 IEEE.

TextureGrow: Object recognition and segmentation with limit prior knowledge (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Network Computing and Information Security, NCIS 2011, May 14, 2011 - May 15, 2011, Guilin, Guangxi, China
Yao Z.; Han Q.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

In this paper we present a new method for automatically visual recognition and semantic segmentation of photographs. Our automatically and rapidly approach based on Cellular Automation. Most of the analysis and description of recognition and segmentation are based on statistical or structural properties of this attribute most of them need plenty of samples and prior Knowledge. In this paper within a few evident samples (not too many) we can first get the texture feature of each component and the structures then select the approximately location randomly of the objects or patches of them then we use the Cellular Automata algorithm to "grow" based on texture of different objects. The grow progress will stop When texture grow to the boundary. By this steps a new method is found which allow us use very few samples and low lever experience and get a rapidly and accuracy way to recognize and segment objects. We found that this new propose gives competitive results with limited experience and samples. 2011 IEEE.

An improved algorithm to generate high quality progressive animation models (EI CONFERENCE) 会议论文 OAI收割
2010 International Conference on Biomedical Engineering and Computer Science, ICBECS 2010, April 23, 2010 - April 25, 2010, Wuhan, China
作者: Zhao J.; Zhang S.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

In computer graphics investigation has been made in many years in progressive models generation to alleviate the workload of visualization processing. However most of the existing algorithms only focus on static meshes and very little works are to deal with animation models. In this paper we propose an improved method for generating progressive multiresolution animation models. By the method we first use a normal deviation parameter to improve the famous QEM method as our basic edge contraction metric to generate a base hierarchy. The sequence of the simplified models is generated progressively from the first frame to the last one. Based on the edge contraction sequence in the previous frame the contraction order in the current frame is adjusted according to the deformation degree. We demonstrate that our method works efficiently and can generate better approximations with well-preserved features than previous methods. 2010 IEEE.

Study on medical X-ray coherent scatter imaging and processing based digital flat detector (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: Li B.; Zhao J.; Li B.; Li B.; Liu J.

收藏 | 浏览/下载：31/0 | 提交时间：2013/03/25

It is introduced a novel imaging technique for medical diagnostic X-ray coherent scatter in this paper. A set of experimental equipment for X-ray coherent scatter imaging was set up with X-ray digital flat detector and medical diagnostic X-ray source. According to this equipment the scatter images obtained are made of some circles with the same center. It is vital to calculate the energy template to classify the different samples. It is difficult to separate them using the traditional threshold method due to noise and overlapped shadow. In this paper the image was transformed a binary image by using K-Means algorithm and Mathematical Morphology Methods. The effective region was extracted from the binary image inside the orthogonal energy projection space then to calculate the centroid of rings. Consequently the curve of the energy distribution was built. The experiment results show that our method is reasonable and feasible. The technique will have wide foreground of application .Besides the imaging of human bone content it can be used for various imaging of tissue and organs in biology. 2010 IEEE.

Optimal multiresolution dynamic models generation based on triangle importance (EI CONFERENCE) 会议论文 OAI收割
2nd International Conference on Image Analysis and Signal Processing, IASP'2010, April 12, 2010 - April 14, 2010, Xiamen, China
作者: Zhao J.; Zhang S.

收藏 | 浏览/下载：20/0 | 提交时间：2013/03/25

In this paper we propose an efficient method to generate optimal multiresolution dynamic models. By the method we define the triangle importance degree as a weight parameter to be embedded to the edge contraction cost so the new metric can not only measure distance error but also reflect geometric variation of local areas. A deformation degree weight is appended to the aggregated edge contraction cost for the whole animation thus sharp features on areas with large deformation can be preserved. In addition a process of mesh optimization and validity check can further alleviate the geometric distortion of the approximations. Our approach is efficient in operation easy for implementation and as a result high quality of dynamic approximations with well-preserved fine details can be generated at any given frame. 2010 IEEE.