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We propose and experimentally demonstrate an ultra-broadband metamaterial absorber based on photonic topological transition by using metals with large real part of permittivity (ε′). The simulation results show that the absorptivity is larger than 0.9 in the wavelength range from 400 nm to 2832 nm. The simulation results also show that the absorption effect is insensitive to the incident angle and polarization. According to the effective medium theory, the ultra-broad bandwidth is originated from the photonic topological transition. In addition, the analyses reveal that the absorption bandwidths can be extended by manipulating the wavelengths of photonic topological transition (PTT) points with large-ε′ metals. Furthermore, an ultra-broadband metamaterial absorber with multilayer films is fabricated by using standard film deposition techniques. The measured results show that the absorptivity is larger than 0.9 under normal incidence over the measured wavelength range of 400–2500 nm. This metamaterial absorber is expected to be potential candidate for various applications, such as thermal photovoltaic energy conversion, detectors, and solar cells.

PTSD symptoms were pervasive among children and adolescents after experiencing or exposure to traumatic events. Screening and diagnosis of PTSD symptoms is crucial in trauma-related research and practice. The 13-item Children's Revised Impact of Event Scale (CRIES) has been demonstrated to be a valid and reliable tool to achieve this goal. This study was designed to examine the psychometric properties of the 13-item CRIES in a sample of Chinese debris flood victims.A total of 268 participants (145 girls, 123 boys) aged 8-18 years were recruited from an integral part of a service oriented project, supported by the Institute of Psychology, Chinese Academy of Sciences following the debris flood. The participants were given the 13-item CRIES 3 months after the debris flood.The results of confirmatory factor analysis indicated that a two-factor structure (intrusion+arousal vs avoidance) emerged as the model best fit in total sample, boys and girls subsamples, respectively. The scale was also demonstrated to have good internal consistency (Cronbach's alpha = 0.83).The study confirmed the good psychometric properties of the CRIES and its' applicability to Chinese children and adolescents. Moreover, these findings imply that the CRIES factor structure is stable across age, gender, and different types of trauma.