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One-dimensional ferroelectric nanomaterials have attracted attention due to excellent properties compared to their bulk thin film counter parts. In the Letter featured on the back cover, Hyunwoo Choi et al. (pp. 59–61) have investigated the mechanical fractures and corresponding domain structure changes of polycrystalline PbTiO3 nanotubes. The cover image shows the changes of morphology and domain structures of PbTiO3 nanotubes after mechanical fracture. The authors found that nanotubes synthesized above 400 °C clearly showed a ferroelectric PbTiO3 phase and the nanotubes synthesized above 500 °C underwent mechanical fracture. After the mechanical fracture, the average size of both grains and domains increased and the average aspect ratio decreased.