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Stimuli‐responsive block copolymer nanoparticles (NPs) have received close attention in recent years owing to their tremendous application potential in smart materials. Azobenzene‐containing NPs are widely studied due to the advantages of light as a stimulus and fast reversible trans–cis isomerization of azobenzene chromophores. However, the inefficient preparation process and difficult reversible transformation of morphologies limit their development. Herein it is demonstrated that the light‐triggered reversible swelling behavior of wormlike NPs with high azobenzene content could be realized via confined deformation. These worms are prepared in large quantities via polymerization‐induced self‐assembly based on the copolymerization of 11‐(4‐(4‐butylphenylazo)phenoxy)undecyl methacrylate (MAAz) and N‐(methacryloxy)succinimide (NMAS) monomers. Upon UV/visible light irradiation, the reversible deformation of worms is achieved when the feed molar ratio of NMAS/MAAz is relatively high or via crosslinking using diamines, which leads to the reduction of the photoisomerization efficiency. The diameter variation of the worms is influenced by the amount and types of crosslinkers. Moreover, the scalability of this strategy is further proved by the fabrication of photo‐ and reductant‐responsive crosslinked worms. It is expected that this study not only provides a new route to affording reversible photoresponsive NPs but also offers a unique insight into the reversible photodeformation mechanism of azobenzene‐containing NPs. [ABSTRACT FROM AUTHOR]

Many marine organisms are exposed to decreasing O2 levels due to warming-induced expansion of hypoxic zones and ocean deoxygenation (DeO2). Nevertheless, effects of DeO2 on phytoplankton have been neglected due to technical bottlenecks on examining O2 effects on O2-producing organisms. Here we show that lowered O2 levels increased primary productivity of a coastal phytoplankton assemblage, and enhanced photosynthesis and growth in the coastal diatom Thalassiosira weissflogii. Mechanistically, reduced O2 suppressed mitochondrial respiration and photorespiration of T. weissflogii, but increased the efficiency of their CO2 concentrating mechanisms (CCMs), effective quantum yield and improved light use efficiency, which was apparent under both ambient and elevated CO2 concentrations leading to ocean acidification (OA). While the elevated CO2 treatment partially counteracted the effect of low O2 in terms of CCMs activity, reduced levels of O2 still strongly enhanced phytoplankton primary productivity. This implies that decreased availability of O2 with progressive DeO2 could boost re-oxygenation by diatom-dominated phytoplankton communities, especially in hypoxic areas, with potentially profound consequences for marine ecosystem services in coastal and pelagic oceans. Sun et al. investigate the effects of current ambient and potential future oxygen levels on phytoplankton growth and photosynthesis with field observations and mesocosm and lab experiments. Their results demonstrate positive effects of low O2 on phytoplankton growth, photosynthesis, and inorganic carbon acquisition at current and future high levels of CO2. [ABSTRACT FROM AUTHOR]

As implant substitutes are increasingly applied to the clinic, the infection caused by implants has become one of the most common complications, and the modification of the antibacterial function of the implant can reduce such complications. In this work, a well-defined bowl-shaped nanostructure coating with photocatalytic and photothermal synergistic antibacterial properties was prepared on Ti-19Zr-10Nb-1Fe (TZNF) alloy. The coating is obtained by spin-coating and sintering TiO2 precursors templated from self-assembled microspheres of polystyrene-poly(4-vinylpyridine) (PS-P4VP) amphiphilic block polymer on TZNF alloy. PS-P4VP provides the bowl-shaped TiO2 nanostructures doped with C, N elements, reducing the band-gap of TiO2, which can absorb near-infrared (NIR) light to release reactive oxygen species and produce photothermal conversion. The bowl structure is expected to enhance the utilization of light via the reflection in the confined space. The bowl-shaped surface has 100% antibacterial rates after 30 min of NIR light irradiation. In addition to antibacterial properties, the bowl-shaped surface has better hydrophilicity and protein adsorption capacity. The amount of protein adsorbed on TZNF with the bowl-shaped structures was six times that of TZNF. Hence, the bowl-shaped nanostructure can promote the proliferation and adhesion of osteoblasts, the cell proliferation rate was increased by 10–30%. [ABSTRACT FROM AUTHOR]

Graph neural networks (GNNs) have attracted extensive research attention in recent years due to their capability to progress with graph data and have been widely used in practical applications. As societies become increasingly concerned with the need for data privacy protection, GNNs face the need to adapt to this new normal. Besides, as clients in federated learning (FL) may have relationships, more powerful tools are required to utilize such implicit information to boost performance. This has led to the rapid development of the emerging research field of federated GNNs (FedGNNs). This promising interdisciplinary field is highly challenging for interested researchers to grasp. The lack of an insightful survey on this topic further exacerbates the entry difficulty. In this article, we bridge this gap by offering a comprehensive survey of this emerging field. We propose a 2-D taxonomy of the FedGNN literature: 1) the main taxonomy provides a clear perspective on the integration of GNNs and FL by analyzing how GNNs enhance FL training as well as how FL assists GNN training and 2) the auxiliary taxonomy provides a view on how FedGNNs deal with heterogeneity across FL clients. Through discussions of key ideas, challenges, and limitations of existing works, we envision future research directions that can help build more robust, explainable, efficient, fair, inductive, and comprehensive FedGNNs.

As implant substitutes are increasingly applied to the clinic, the infection caused by implants has become one of the most common complications, and the modification of the antibacterial function of the implant can reduce such complications. In this work, a well-defined bowl-shaped nanostructure coating with photocatalytic and photothermal synergistic antibacterial properties was prepared on Ti-19Zr-10Nb-1Fe (TZNF) alloy. The coating is obtained by spin-coating and sintering TiO 2 precursors templated from self-assembled microspheres of polystyrene-poly(4-vinylpyridine) (PS-P4VP) amphiphilic block polymer on TZNF alloy. PS-P4VP provides the bowl-shaped TiO 2 nanostructures doped with C, N elements, reducing the band-gap of TiO 2 , which can absorb near-infrared (NIR) light to release reactive oxygen species and produce photothermal conversion. The bowl structure is expected to enhance the utilization of light via the reflection in the confined space. The bowl-shaped surface has 100% antibacterial rates after 30 min of NIR light irradiation. In addition to antibacterial properties, the bowl-shaped surface has better hydrophilicity and protein adsorption capacity. The amount of protein adsorbed on TZNF with the bowl-shaped structures was six times that of TZNF. Hence, the bowl-shaped nanostructure can promote the proliferation and adhesion of osteoblasts, the cell proliferation rate was increased by 10-30%., (© The Author(s) 2022. Published by Oxford University Press.)