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Self-assembly of amphiphilic block copolymer in water suffers from the undesired encapsulation of hydrophobic reactive motifs in core-forming block, which deteriorates the performance as aqueous catalysts. This problem can be circumvented by polymerisation-induced self-assembly (PISA). Herein, we report a new strategy for one-pot synthesis of reactive block copolymer nanoparticles whose hydrophobic reactive motifs decorate surrounding core-shell interfaces. We demonstrate fast RAFT aqueous dispersion polymerisation of a commercial available specialty monomer, diacetone acrylamide (DAAM), under visible light irradiation at 25 o C. PISA is induced by polymerisation via sequentially dehydration, phase separation and reaction acceleration, and thus complete conversion in 30 min. Replacement of minimal DAAM by NH3 + -monomer induces slight hydration of the core-forming block, and thus a low polydispersity of resultant statistic-block copolymer. Moreover, simultaneous in situ self-assembly and chain growth favours adjustment of newly-added NH3 + -units outward to core-shell interfaces while the major DAAM units collapse to hydrophobic PISA-cores. Both lead to timely and selective self-assembly into the new reactive nanoparticles whose NH3 + -motifs decorate surrounding core-shell interfaces. These nanoparticles well suit fabrication of advanced nanoreactors whose hydrophobic dative metal centres decorate surrounding interfaces via simultaneous imine conversion and Zn(II)-coordination. Such PISA-nanostructures endow hydrophobic metal centres with huge and accessible specific surface area and are stabilized by water-soluble shells. Therefore, this strategy holds fascinating potentials for the fabrication of metalloenzyme-inspired aqueous catalysts.Enzyme inspired interface-decorated media-accessible reactive nanoparticles are now available via PISA by aqueous dispersion RAFT of commodity-DAAM with minimal NH 3 + -monomer.

Arrays of nanowires (NWs) are currently being established as vehicles for molecule delivery and electrical- and fluorescence-based platforms in the development of biosensors. It is conceivable that NW-based biosensors can be optimized through increased understanding of how the nanotopography influences the interfaced biological material. Using state-of-the-art homogenous NW arrays allow for a systematic investigation of how the broad range of NW densities used by the community influences cells. Here it is demonstrated that indium arsenide NW arrays provide a cell-promoting surface, which affects both cell division and focal adhesion up-regulation. Furthermore, a systematic variation in NW spacing affects both the detailed cell morphology and adhesion properties, where the latter can be predicted based on changes in free-energy states using the proposed theoretical model. As the NW density influences cellular parameters, such as cell size and adhesion tightness, it will be important to take NW density into consideration in the continued development of NW-based platforms for cellular applications, such as molecule delivery and electrical measurements.

PurposeLive streaming commerce, a new form of social commerce where firms integrate with broadcasters, community members and customers in live chat rooms for real-time interaction to help sell products, has become increasingly popular. However, factors that impact the success of live streaming commerce are not fully explored. The purpose of this study is to examine these factors by exploring the relationships among customer trust (i.e., trust in broadcasters, community members, and products) and customer engagement, and the mediating role of swift guanxi.Design/methodology/approachThe authors surveyed 422 customers who have watched Taobao Live, one of the largest live streaming commerce sites in China, and used their questionnaires to test the research model employing partial least squares modeling.FindingsThe authors’ results indicate that trust in broadcasters has a positive effect on trust in products and community members, which positively influences trust in products. Additionally, swift guanxi has a fully mediating effect on the relationship between customers' trust in broadcasters and customer engagement.Originality/valueFirst, from the theoretical perspective, this study comprehensively identifies three types of trust, explores the transfer relationships among trust in broadcasters, community members, and products based on Trust Transfer Theory. In addition, this study examines the mediating influence of swift guanxi on the relationship between customer trust and engagement. Second, from the managerial perspective, the study provides insights to help broadcasters and practitioners use live streaming to facilitate shopping.