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Novel wire‐shaped polymer solar cells that have high performance are developed by introducing a thin layer of titania nanoparticles that increases the charge separation and transport and an aligned carbon nanotube fiber electrode that increases their stability. These solar cell wires are easily woven into flexible clothes that serve as lightweight and deformable power sources for portable electronic devices. [ABSTRACT FROM AUTHOR]

Abstract: Sediments collected from an urban creek in China exhibited high acute toxicity to Hyalella azteca with 81.3% of sediments being toxic. A toxic unit (TU) estimation demonstrated that the pyrethroid, cypermethrin, was the major contributor to toxicity. The traditional TU approach, however, overestimated the toxicity. Reduced bioavailability of sediment-associated cypermethrin due to sequestration explained the overestimation. Additionally, antagonism among multiple contaminants and species susceptibility to various contaminants also contributed to the unexpectedly low toxicity to H. azteca. Bioavailable TUs derived from the bioavailability-based approaches, Tenax extraction and matrix-solid phase microextraction (matrix-SPME), showed better correlations with the noted toxicity compared to traditional TUs. As the first successful attempt to use matrix-SPME for estimating toxicity caused by emerging insecticides in field sediment, the present study found freely dissolved cypermethrin concentrations significantly improved the prediction of sediment toxicity to H. azteca compared to organic carbon normalized and Tenax extractable concentrations. [Copyright &y& Elsevier]

The present study examined the effects of bioturbation by the oligochaete Lumbriculus variegatus on bioavailability and toxicity of sediment-associated polycyclic aromatic hydrocarbons (PAHs) to the oligochaete and the epi-benthic amphipod Hyalella azteca. Various densities of L. variegatus in sediment were used to represent different levels of bioturbation. Total sediment concentration declined with increasing worm density, but bioavailability of PAHs estimated using the biomimetic extractions showed no significant difference among treatments with different worm densities. Alternatively, PAH bioaccumulation by L. variegatus decreased and the growth of the worms was reduced at the highest worm density, which was probably due to overcrowding of organisms, food competition and increasing release of PAHs by bioturbation. Additionally, co-exposure with high density of L. variegatus to contaminated sediment significantly increased PAH accumulation and mortality of H. azteca. The increased toxicity was probably because of the transport of sediment-associated contaminants to sediment surface and water column by the bioturbation by L. variegatus. Overall, the present study showed that bioturbation may alter the toxicity of contaminants in sediment to other organisms, thus the presence of benthic invertebrates and their interactions with the sediment should be considered in future sediment risk assessment. [Copyright &y& Elsevier]