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Hu P.-J.,Sun Yat Sen University | Gan Y.-Y.,Sun Yat Sen University | Tang Y.-T.,Sun Yat Sen University | Tang Y.-T.,Guangdong Provincial Key Laboratory | And 4 more authors.
Pedosphere | Year: 2012

Knowledge of cellular metal homeostasis will provide a better understanding of the mechanisms involved in metal tolerance and hyperaccumulation in metal-hyperaccumulating plants. Energy dispersive X-ray spectrometry (EDS) was used to determine the localization of cadmium (Cd) in leaves of the Zn/Cd hyperaccumulator Picris divaricata which had a shoot Cd concentration of 565 mg kg -1 after 2 weeks of growth in solution culture supplying 10 mol L -1 CdCl 2. The results indicated that Cd was distributed mainly in the trichomes, upper and lower epidermis and bundle sheath cells, with a relatively low level of Cd in mesophyll cells. Mesophyll protoplasts isolated from leaves remained viable after 24 h exposure to CdCl 2 at a concentration up to 1 mmol L -1, indicating their high tolerance to Cd. The intracellular Cd was visualized by staining with Leadmium Green dye, a cellular permeable Cd fluorescence probe. The results showed that the majority of protoplasts (> 82%) did not accumulate Cd, with only a minority (< 18%) showing Cd accumulation. In the Cd-accumulating protoplasts, Cd accumulation was depressed by the addition of Fe 2+, Mn 2+ and the metabolic inhibitor carbonyl cyanide m-chlorophenylhydrazone (CCCP), but not by Ca 2+ or Zn 2+. Furthermore, the entire process of Cd uptake from external solution into the cytoplasm and subsequent sequestration into vacuoles was successfully recorded by confocal images. These results suggested that reduced cellular Cd accumulation and efficient Cd vacuolar sequestration in mesophyll cells might be responsible for cellular Cd tolerance and distribution in the leaves of P. divaricata. © 2012 Soil Science Society of China.

Zhang W.-H.,Sun Yat Sen University | Zhang W.-H.,Oak Ridge National Laboratory | Zhang W.-H.,Guangdong Provincial Key Laboratory | Wu Y.-X.,Sun Yat Sen University | Simonnot M.O.,University of Lorraine
Pedosphere | Year: 2012

This paper presents a review of soil contamination resulting from e-waste recycling activities, with a special focus on China, where many data have been collected for a decade. Soils in the e-waste areas are often contaminated by heavy metals and organic compounds, mainly polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs), polychlorinated and polybrominated biphenyls (PCBs and PBBs), dechlorane plus (DP), hexabromocyclododecanes (HBCDs), polychlorinated and polybrominated dibenzo- p-dioxins (PCDDs and PBDDs), and polychlorinated and polybrominated dibenzofurans (PCDFs and PBDFs), while other compounds, not systematically monitored, can be found as well. Pollutants are generally present in mixtures, so pollution situations are complex and diversified with a gradient of contamination from agricultural soils to hot spots at e-waste sites and mainly in open burning areas. It has been proved that pollutants were transferred to the food chain via rice in China, and that the population was threatened since high levels of various pollutants were detected in blood, placentas, hair, etc., of residents of e-waste sites. Eventually, soil remediation techniques are reviewed. Although there are many available techniques devoted to heavy metals and persistent organic pollutants, the current techniques for the e-waste sites, where these contaminants coexist, are very sparse. Phytoremediation has been investigated and co-cropping appears as a promising approach for the slightly contaminated agricultural soils. In some cases, different remediation techniques should be combined or trained, while the influence of coexisting contaminants and the removal sequence of contaminants should be considered. In hot spots, physical and chemical techniques should be used to reduce high pollution levels to prevent further pollutant dissemination. This review highlights the urgent needs for 1) characterization of pollution status in all the countries where e-wastes are recycled, 2) research on fate and toxicity of pollutant mixtures, and 3) development of combined techniques and strategies to remediate agricultural fields and hot spots of pollution. © 2012 Soil Science Society of China.

Zhang G.,Sun Yat Sen University | Zhang G.,Guangdong Provincial Key Laboratory | Zheng Z.,Guangdong Provincial Key Laboratory | Shen X.,Zhejiang University | And 3 more authors.
International Journal of Remote Sensing | Year: 2011

Landsat-7 Enhanced Thematic Mapper Plus (ETM+) images were used to interpret hydrocarbon-induced alterations in the northwestern part of the Songliao Basin, northeast China. Spectral enhancements for locating hydrocarbon-related minerals on images included principal component analysis (PCA), band ratioing, optimum index factor (OIF) and false colour composite (FCC). Four principal component (PC) and four band ratio images showed outstanding spectral response of hydrocarbon-induced mineral and sediment assemblages: 1345-PC3 (third PC image on bands 1, 3, 4 and 5), 1357-PC3, 2357-PC3 and 3457-PC4, and band ratios 3/1, 4/3, 7/5 and 4/3-2/3. Five OIF-defined FCCs were informative and clear for anomaly interpretation. Consequently, heavy oil prospect areas totaling 159 km2 were delineated. Acidolysis hydrocarbon measurements of ground soil samples suggest high soil concentrations of light hydrocarbons, indicating that the tonal anomalies in the images have a geological origin. Thus, remote sensing interpretation can be a useful primary exploration tool in hydrocarbon-altered areas, provided that techniques are adapted to site characteristics. © 2011 Taylor & Francis.

Wang B.,CAS South China Botanical Garden | Wang B.,Guangdong Institute of Microbiology | Wang B.,Guangdong Provincial Key Laboratory | Wang B.,Guangdong Open Laboratory of Applied Microbiology | And 7 more authors.
International Biodeterioration and Biodegradation | Year: 2010

Shewanella decolorationis S12 is capable of using azo compounds as terminal electron acceptors for respiration. However, knowledge about membrane proteins involved in this biochemical process is still limited. In addition, little is known about cell growth of this species in response to the increasing level of azo dye. In the present study, different culture methods were used to compare the biomass production rates of strain S12 in the presence of a high polarity azo dye, amaranth, as the sole terminal electron acceptor. The use of a fed-batch fermentor culture method allowed a much higher biomass accumulation in the presence of higher amounts of amaranth, compared to static serum bottle culture. Membrane proteome profiles were obtained by two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometry (MALDI-TOF/TOF/MS) for cells grown with different amounts of amaranth under anaerobic conditions. Three proteins Ndk, ClpP, and ArgC were found in markedly increased abundance in response to the growth increases in the presence of amaranth. Bioinformatics analysis implicated that these three proteins may be involved in azo respiration and energy conservation in strain S12. These findings provide valuable information for better understanding the extracellular azo respiration of S. decolorationis S12. © 2010 Elsevier Ltd.

Chu Y.-Y.,Sun Yat Sen University | Chu Y.-Y.,Guangdong Provincial Key Laboratory | Huang L.-J.,Carnegie Mellon University | Zhang Q.-X.,Sun Yat Sen University | And 3 more authors.
Proceedings - 7th International Conference on Intelligent Computation Technology and Automation, ICICTA 2014 | Year: 2015

Unsafe behavior of workers is the key cause of accidents in production. Behavior-based safety model has been developed to catch all aspects of workers' behavior safety to improve the enterprise safety level. To study the complex cause-effect relationship between the safety input and workers' behavior safety in the mining enterprise, questionnaire investigations have been adopted in the mining enterprise. And mutual or recursive causality to understand the dynamics of behavior safety system has been analyzed by the information feedback in the system dynamic simulation, which is in accordance with the results of the questionnaires. Using the system dynamics software, Vensim PLE 5.4b, simulation cases about the mining enterprise workers' safety behavior system have been made to show the process of workers' behavior safety improvement and different factor increments. It is proved that the developing tendency of safety level of the mining enterprise can be predicted by system dynamic simulation and simulation results can provide support for the making of decisions on safety input. © 2014 IEEE.

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