Objective To study the characterization apportionment of main ion concentrations of PM10 under the influence of trajectory wind direction in London. Methods PM10 samples from 1 May 1995 to 30 October 1995 of Oxford St...Objective To study the characterization apportionment of main ion concentrations of PM10 under the influence of trajectory wind direction in London. Methods PM10 samples from 1 May 1995 to 30 October 1995 of Oxford Street of Central London were collected, the metals and anions of which were measured using atomic absorption spectrometry （AAS） and ion chromatography （IC）. Composite trajectories representative of the air mass arriving in London at the same period were calculated based on basic routine back trajectories from the British Atmospheric Data Centre （BADC）. Results Concentration apportionments of main ions were similar when the trajectory was plotted back at 6 h, 12 h, and 24 h, some were obviously different. Mg, Ba, Pb, and Cu had similar peak apportionments at the area 180°-320°, but Zn and Ni at the area of 90°-270°, NO3^- and SO4^2- at the area of 100°-220°. Cl^- concentration peak apportionment was at the area of 220°-300°, which showed that Cl^- mainly came from the North Sea. Conclusion Trajectory wind direction has important effect on ion concentration apportionment of PM10 in London. The ions have similar concentration peak apportionments or their correlation coefficients are statistically significant.展开更多
1.EMT in cancer metastasis and chemoresistance Cancer metastasis is contingent on the epithelial-mesenchymal transition(EMT)of cancer cells.During EMT,epithelial cancer cells transform into a mesenchymal phenotype,whi...1.EMT in cancer metastasis and chemoresistance Cancer metastasis is contingent on the epithelial-mesenchymal transition(EMT)of cancer cells.During EMT,epithelial cancer cells transform into a mesenchymal phenotype,which endows cancer cells with enhanced migratory and invasive abilities,promoting their dissemination throughout the body.EMT also contributes significantly to chemoresistance,allowing cancer cells to survive and metastasize even after chemotherapy[1].展开更多
基金This work was supported by China Scholarship Council.
文摘Objective To study the characterization apportionment of main ion concentrations of PM10 under the influence of trajectory wind direction in London. Methods PM10 samples from 1 May 1995 to 30 October 1995 of Oxford Street of Central London were collected, the metals and anions of which were measured using atomic absorption spectrometry （AAS） and ion chromatography （IC）. Composite trajectories representative of the air mass arriving in London at the same period were calculated based on basic routine back trajectories from the British Atmospheric Data Centre （BADC）. Results Concentration apportionments of main ions were similar when the trajectory was plotted back at 6 h, 12 h, and 24 h, some were obviously different. Mg, Ba, Pb, and Cu had similar peak apportionments at the area 180°-320°, but Zn and Ni at the area of 90°-270°, NO3^- and SO4^2- at the area of 100°-220°. Cl^- concentration peak apportionment was at the area of 220°-300°, which showed that Cl^- mainly came from the North Sea. Conclusion Trajectory wind direction has important effect on ion concentration apportionment of PM10 in London. The ions have similar concentration peak apportionments or their correlation coefficients are statistically significant.
基金support from the National Science Foundation CAREER Award,USA(Grant No.:2143972)the National Institutes of Health through the Award,USA(Grant No.:R15CA274349).
文摘1.EMT in cancer metastasis and chemoresistance Cancer metastasis is contingent on the epithelial-mesenchymal transition(EMT)of cancer cells.During EMT,epithelial cancer cells transform into a mesenchymal phenotype,which endows cancer cells with enhanced migratory and invasive abilities,promoting their dissemination throughout the body.EMT also contributes significantly to chemoresistance,allowing cancer cells to survive and metastasize even after chemotherapy[1].
