To examine the mechanism of the network formation of silk fibroin (SF), monodispersed colloidal particles (MDCPs) are used as well defined foreign substrates to quantify their effect on the primary nucleation of β‐crystallites in molecular networks (silk nanofibrils) and the hierarchical network formation of SF. It follows that MDCPs are capable of accelerating the SF gelation by reducing the multistep nucleation barrier, which gives rise to a high density of silk fibril domain networks due to the increase of primary nucleation sites. Consequently, through governing the change in the hierarchical mesoscopic structure, the macroscopic performance of silk materials (e.g., the rheological properties of SF hydrogels and the tensile stress of fibers) can be controlled directly. As SF hydrogels represent a typical example of weak fibril domain–domain network interactions, the increase of fibril domain density leads to weaker gels. On the other hand, SF fibers correspond to strong fibril domain–domain network interactions, the increase of fibril domain density ends up with much tougher fibers. The knowledge obtained provides a facile strategy in controlling the complex hierarchical structure and macroscopic performance of SF materials, and offers useful routes for general design and functionalization of soft materials.

Introduction Influenza has been linked to the crowding in emergency departments (ED) across the world. The impact of the Coronavirus Disease 2019 (COVID-19) pandemic on China EDs has been quite different from those during past influenza outbreaks. Our objective was to determine if COVID-19 changed ED visit disease severity during the pandemic. Methods This was a retrospective cross sectional study conducted in Nanjing, China. We captured ED visit data from 28 hospitals. We then compared visit numbers from October 2019 to February 2020 for a month-to-month analysis and every February from 2017 to 2020 for a year-to-year analysis. Inter-group chi-square test and time series trend tests were performed to compare visit numbers. The primary outcome was the proportion of severe disease visits in the EDs. Results Through February 29 th 2020, there were 93 laboratory-confirmed COVID-19 patients in Nanjing, of which 40 cases (43.01%) were first seen in the ED. The total number of ED visits in Nanjing in February 2020, were dramatically decreased ( n = 99,949) in compared to January 2020 ( n = 313,125) and February 2019 ( n = 262,503). Except for poisoning, the severe diseases in EDs all decreased in absolute number, but increased in proportion both in year-to-year and month-to-month analyses. This increase in proportional ED disease severity was greater in higher-level referral hospitals when compared year by year. Conclusion The COVID-19 outbreak has been associated with decreases in ED visits in Nanjing, China, but increases in the proportion of severe ED visits.

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Enzymatic reactions are often terminated by severe aqueous environments. Inspired by bio‐protection of silk cocoons, a system of silk fibroin (SF) nanococoons is developed, which is capable of providing a bio‐protective environment for enzymatic activities on one hand, and facilitating the process of cascade enzymatic reactions on the other hand. This gives rise to the significant enhancement in enzymatic stability and efficacy. For instance, the protected glucose oxidase and horseradish peroxidase enzymes exhibit a 17.5‐ and 7.0‐fold increase when stored at 60 °C (>50% activity; ≈28 h) and 25 °C (>67.5% activity; ≈14 days), respectively, compared with free enzymes. It follows that this protective effect is subject to the mutual templated crystallization between enzymes and SF molecules, which prevents enzyme molecules from unfolding. In animal experiments, it shows that alcohol oxidase and catalase protected by silk nanococoons are able to reduce the alcohol levels of intoxicated mice with >5.0‐time efficacy at the alcohol decomposition level of >80% in 4.0 h compared with the unprotected. By bio‐inspiration of silk cocoons, the silk bio‐nanoreactors demonstrate the significant potential applications in biomedicine.