Flavonoids are well known as antibacterial agents against a wide range of pathogenic microorganism. With increasing prevalence of untreatable infections induced by antibiotic resistance bacteria, flavonoids have attracted much interest because of the potential to be substitutes for antibiotics. In this review, the structure-relationship of flavonoids as antibacterial agents is summarized, and the recent advancements on the antibacterial mechanisms of flavonoids are also discussed. It is concluded that hydroxyls at special sites on the aromatic rings of flavonoids improve the activity. However, the methylation of the active hydroxyl groups generally decreases the activity. Besides, the lipopholicity of the ring A is vital for the activity of chalcones. The hydrophobic substituents such as prenyl groups, alkylamino chains, alkyl chains, and nitrogen or oxygen containing heterocyclic moieties usually enhance the activity for all the flavonoids. The proposed antibacterial mechanisms of flavonoids are as follows: inhibition of nucleic acid synthesis, inhibition of cytoplasmic membrane function, inhibition of energy metabolism, inhibition of the attachment and biofilm formation, inhibition of the porin on the cell membrane, alteration of the membrane permeability, and attenuation of the pathogenicity.

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Single crystals of heterovalent Bi-doped CH3NH3PbCl3 perovskite have been successfully grown through the inverse temperature crystallization method. Bandgap narrowing of 300 meV (a 55 nm red-shifting absorption edge) is obtained for the nominal 20% Bi-doped crystal with the host structure and the energy at the top of the valence band invariable. It is observed that the contact between the Au electrodes and single crystals transforms from Ohmic to Schottky, and the conductivity increases with increasing Bi doping level. By contrast, the Bi-doped CH3NH3PbCl3 thin films are also prepared, and the similar bandgap narrowing is found, although the narrowing degree is less than that in single crystals. This work has a comprehensive understanding of Bi-doped single crystals and thin films, providing further optoelectronic applications for these promising solution-processed hybrid perovskite semiconductor materials.

In an effort to mitigate ecological environments and improve human well-being, the Chinese government's largest-ever relocation and settlement programme is underway. Measuring livelihood resilience and further assessing its impact hold the key to strengthening adaptive capacity and well-being in poverty resettlements. Using a household survey of contiguous poor areas in Southern Shaanxi, China, this research proposes a framework to examine livelihood resilience and its impact on livelihood strategies in the context of poverty alleviation resettlement. To provide more comprehensive empirical evidence, we drew on three dimensions of the previously proposed livelihood resilience framework: buffer capacity, self-organizing capacity, and learning capacity. The results show that capital endowments, social cooperation networks, transportation convenience, and skills acquired from education and rural-urban migration can significantly affect the construction of livelihood resilience. The resilience of households that were relocated because of ecological restoration is the highest, followed by households relocated because of disasters; households relocated because of poverty reduction attempts have the lowest resilience. As for indicators of livelihood resilience, physical capital assets and previous work experience play a major role in household livelihood strategies for pursuing non-farming activities, while household size, stable income, social capital, and information sharing result in diversified livelihood strategies. These findings provide policy implications for enhancing livelihood resilience capacities and improving the scope of available livelihood strategies to emerge from the poverty trap and to adapt to the new environment.