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The molecular fingerprint sensing technology based on metasurface has unique attraction in the biomedical field. However, in the terahertz (THz) band, existing metasurface designs based on multi-pixel or angle multiplexing usually require more analyte amount or possess a narrower tuning bandwidth. Here, we propose a novel single-pixel graphene metasurface. Based on the synchronous voltage tuning, this metasurface enables ultra-wideband (∼ 1.5 THz) fingerprint enhancement sensing of trace analytes, including chiral optical isomers, with a limit of detection (LoD) ≤ 0.64 μg/mm2. The enhancement of the fingerprint signal (∼ 17.4 dB) originates from the electromagnetically induced transparency (EIT) effect excited by the metasurface, and the ideal overlap between the light field constrained by single-layer graphene (SLG) and ultra-thin analyte. Meanwhile, due to the unique nonlinear enhancement mechanism in graphene tuning, the absorption envelope distortion is inevitable. To solve this problem, a universal fingerprint spectrum inversion model is developed for the first time, and the restoration of standard fingerprints reaches Rmax2 ≥ 0.99. In addition, the asynchronous voltage tuning of the metasurface provides an opportunity for realizing the dynamic reconfiguration of EIT resonance and the slow light modulation in the broadband range. This work builds a bridge for ultra-wideband THz fingerprint sensing of trace analytes, and has potential applications in active spatial light modulators, slow light devices and dynamic imaging equipments. [ABSTRACT FROM AUTHOR]

China has increased its investment and influence in Central-Eastern European (CEE) countries through the "16 + 1" framework in 2011 and the One Belt One Road (OBOR) initiatives in 2013. Given China's rising influence, this paper explores civilian views of China in the Czech Republic. Using survey analysis of 663 respondents in 11 Czech universities, we find that our respondents' impression of China is neither negative nor positive. By contrast, they do not have a good impression of Russia. Their impression of Japan is the best. Our respondents recognize that China is the most influential player in Asia. Albeit divided, there is a tendency for respondents to believe that China will surpass the USA as the world's leading power, but they cannot reach consensus on whether such development will be peaceful or not. Our survey also finds out that, while the Czech government wishes to get closer to China politically and economically, citizens are somewhat divided on various dimensions of issues concerning China. This is a pattern that continues from the past. The 2013 change of political landscape in the Czech Republic does not seem to have altered many of the societal responses to China. [ABSTRACT FROM AUTHOR]

Discusses the environmental aspects of foreign policy in China. Indepth look at Chinese foreign relations; Increase interest in environmental diplomacy by Beijing; Factors which influenced increased interest.