The Temporal and Spatial Distributions and Influencing Factors of Transboundary Pollution in China.

Transboundary pollution between neighboring regions seriously affects the efficiency of overall environmental governance; however, there are few studies focused on how to estimate the degree of transboundary pollution between different regions. With China as a case study, this article developed a new measurement to estimate the degree of transboundary pollution among regions, and comprehensively investigated the influencing factors of transboundary pollution in China between 2000 and 2013. The results indicate that transboundary pollution effects exist in China. In ascending order, the regions most affected overall by transboundary pollution from polluting enterprises were as follows: eastern region < central region < western region. The reduction in transboundary pollution effects was most prominent for severely polluting enterprises in the eastern and western regions and lightly polluting enterprises in the central region. An analysis of the influencing factors reveals that the regional environmental regulation intensity has a negative feedback effect on the transboundary pollution effects. These findings indicate that polluting enterprises in regions with a low environmental regulation intensity are more inclined to operate in border areas to obtain both the environmental benefits associated with the low local environmental regulation intensity and the market economy benefits associated with neighboring urban regions, thereby aggravating environmental pollution in border areas.

Magnetic liposomes for light-sensitive drug delivery and combined photothermal-chemotherapy of tumors.

The targeted delivery of anticancer drugs for improving the therapeutic efficacy and reducing the side effects has attracted great attention in cancer therapy. In this study, multifunctional magnetic nanoparticles-loaded thermosensitive liposomes (Fe3O4-TSL) were developed for the near-infrared (NIR) laser-triggered release and combined photothermal-chemotherapy of tumors. Doxorubicin (DOX) was encapsulated into the Fe3O4-TSL (DOX-Fe3O4-TSL) via an ammonium sulfate gradient, with an encapsulation efficiency of up to 90.9%. Once treated with NIR laser irradiation, significantly improved drug release was observed in the DOX-Fe3O4-TSL compared to that of DOX-TSL. After an intravenous injection, Fe3O4-TSL tended to enrich in the tumor over time and showed remarkable magnetic resonance imaging (MRI) and photothermal effects. The combined chemo-photothermal therapy study demonstrated that DOX-Fe3O4-TSL could significantly inhibit the tumor growth without causing any significant damage to normal tissues under NIR laser irradiation. These results revealed a great potential for DOX-Fe3O4-TSL for the diagnosis and synergistic therapy of tumors.