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Air environmental quality data (SO2, NO2, and PM10) of six automatic monitoring points monitored in 2010 and fuzzy clustering analysis method were applied to regionalize the atmospheric functional regions in Baotou City. It was demonstrated that the atmospheric functional regions were divided into two classes, which is consistent with the regional actual situation. This study provides a scientific basis for the comprehensive improvement of the urban environmental planning.

To assess how the human exposure to environmental carcinogenic polycyclic aromatic hydrocarbons (PAHs) contaminant generated from a typical oilfield, we used a recommended exposure risk model, appraised with actual measured PAH concentration in an oilfield soils. Hierarchical clustering method was also applied to classfied the total exposure risk (carcinogenic and non-carcinogenic) of 16 PAHs, and four risk grades were obtained as zero risk, low risk, medium risk, and high risk. It was found that ingestion was the major exposure route among the three exposure routes. Risks of dibenz(a,h)anthracene and benzo(a)pyrene were higher than the other contaminants, and represent high risk grade.

The bacterial tobacco wilt caused by Ralstonia solanacearum is one of the most destructive soil-borne diseases worldwide. One strategy to improve the resistance to bacterial wilt is to make use of plant varieties expressing wilt resistance genes. To characterize the genetics of wilt resistance and to identify relevant molecular markers for use in plant breeding, quantitative trait loci (QTLs) affecting tobacco bacterial wilt resistance were mapped in the F2:3 and F2:4 progeny produced from two crosses between the wilt-resistant breeding lines Enshu and Yanyan97 and the susceptible cultivar TI448A. A linkage map containing 118 loci in 24 linkage groups was constructed for 236 lines from the Enshu×TI448A cross, and a linkage map containing 96 loci in 24 linkage groups was constructed for 264 lines from the Yanyan97×TI448A cross. The wilt resistance of the progeny was examined in field trials conducted in Xuancheng, China, in 2010, 2011, and 2012. The disease severity was assessed on stems using separate rating scales. Mapmaker/EXP 3.0 and Mapmaker/QTL 1.1 were used to identify the qBWR-3a, qBWR-3b, qBWR-5a and qBWR-5b QTLs in linkage group 3 and 5; these four loci were strongly associated with resistance and explain 9.00, 19.70, 17.30, and 17.40 % of the variance in resistance, respectively. The close linkage of the markers PT20275 and PT30229 was detected in both the TI448A×Enshu and TI448A×Yanyan97 crosses, and this linkage group could be used to select individual resistant plants. These findings suggest that one strategy to combat bacterial wilt could be to exploit the resistance genes of the Enshu and Yanyan97 strains.