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Hydrogel has a wide range of functionalities and great potential for application in various fields. However, the disadvantages such as weak strength and susceptibility to water loss limit its application in complex environments. In this study, glycerol and water were used as binary solvents to construct dual-network hydrogels by mixing polyvinyl alcohol (PVA) and the natural polymer gelatin (GEL) through a simple one-pot method. Glycerol was introduced to form hydrogen bonds with PVA and GEL, on the one hand, resulting in the excellent mechanical properties of the prepared hydrogels; on the other hand, glycerol also endowed the hydrogels with excellent anti-drying and anti-freezing properties, which enabled them to be stably applied in extreme environments. In addition, by adjusting the proportion of glycerol, the mechanical properties of the hydrogel can be adjusted to adapt to the applications in different scenarios. This kind of organic hydrogel with adjustable mechanical properties for anti-drying and anti-freezing has great potential for development in various fields. Highlights * Organic hydrogels with high mechanical strength were prepared by the one-pot method. * The anti-drying and anti-freezing gel is suitable for extreme conditions. * The multifunctional gel is removable and can be reused to save costs. KEYWORDS dual network hydrogel, hydrogen bonding, mechanical properties, polyvinyl alcohol, 1 | INTRODUCTION Hydrogels are three-dimensional polymer networks containing large amounts of water, and most of them have high water content, biocompatibility, and functionality. (1) Hydrogels with excellent mechanical properties [...]

Poor high-temperature stability (HTS) and weak microwave absorption performance (MAP) are a major restriction for wave-absorbing materials in elevated temperature ambient. Consequently, the Stöber process and the sol–gel method are first devised and used to create multi-core/shell SiO2@Al2O3 nanostructures (MCSNs) on Ti3AlC2 (TAC). The MCSNs with a thickness of 135–215 nm raise the starting oxidation temperature of the matrix by 400°C. Furthermore, the weight gain drops from 17.44 to 2.32% within 1 h at 800°C. The effective absorption bandwidth with a reflection loss (RL) ≤ −10 dB of the MCSNs-coated TAC is 3.25 GHz (8.68–11.27 and 11.63–12.29 GHz) at a thickness of 2.0 mm, which is 4.7 times that of the matrix. The minimum RL is reduced by a factor of 2.77 from −10.68 to −29.55 dB. The enhanced MAP is due to the introduced multiple reflection events and scattering mechanism as well as the enhanced electronic polarization, interface polarization, and polarization relaxation. The growth of the MCSNs provides a reference for the design and preparation of bifunctional materials with good HTS and MAP.

Overcoming hypoxia is an urgent clinical challenge in acute kidney injury (AKI) treatment. Specifically, hypoxia upregulates xanthine oxidase (XO) expression and induces reactive oxygen species (ROS) generation, which exacerbates renal injury. Herein, a therapeutic strategy of self‐supply oxygen for highly efficient AKI therapy is developed, in which the biocompatible CeO2 nanorods modified by poly(ethylene glycol)‐folic acid conjugate (CeFA) catalytically convert ROS into oxygen and effectively relieve hypoxia in injured renal tissues. Modification with poly(ethylene glycol)‐folic acid conjugate allows the catalysts to be accumulated in injured renal tissues, and the high activity of CeFA guaranteed long‐lasting endogenous ROS decomposition to continuously supply oxygen. This resulted in the relief of renal hypoxia, which inhibits XO expression, reduces ROS generation and thereafter essentially alleviates kidney injury. Moreover, CeFA significantly reduces lipopolysaccharide‐induced ROS injury and reverses hypoxia in the murine AKI model, where the levels of kidney function indicators remain normal, and inflammation is alleviated without negative effects. This study offers a promising strategy for relieving hypoxia and protecting the kidney from AKI. This methodology is anticipated to provide a valuable approach for treating other oxygen‐dependent diseases and events, such as tumors and stroke. [ABSTRACT FROM AUTHOR]

The construction of urban agglomerations around Poyang Lake is an important starting point of the strategy for the improvement of central China, but the spatial agglomeration of industry and population brings great pressure to the ecological environment. It is of great practical value to explore the impact of rapid urbanization on the water use efficiency of important ecological functional areas. Considering the undesired output of industrial production, this paper adopts the SE-SBM model to measure industrial green water use efficiency, comprehensively considers different aspects of urbanization of the urban agglomeration around Poyang Lake, empirically tests its inhibiting or boosting effect on industrial green water use and explores its spatial spillover effect with the help of a spatial metrology model. The results show that (1) the industrial green water use efficiency of urban agglomerations shows an overall upward trend, and the efficiency value of central cities is significantly higher than that of non-central cities and continues to show a state of diffusion; (2) social urbanization, environmental urbanization, and balanced urbanization can significantly improve industrial green water use efficiency, while industrial urbanization or industrialization inhibits the improvement in water use efficiency; (3) considering the spatial spillover factor, there are significant positive local effects between population urbanization and balanced urbanization, and significant positive spatial spillover effects between industrial urbanization and environmental urbanization; (4) the original model can pass the significance test by replacing the output-oriented water use efficiency with the input-oriented or non-oriented water use efficiency; the study area is extended to Jiangxi Province, and the impact of urbanization on industrial water use efficiency is basically consistent. We should adhere to the new type of urbanization that improves well-being and is friendly to the environment, rationally plan the industrial spatial pattern of urban agglomerations, adhere to the ecological and environmental threshold on undertaking industrial transfer, and promote the flow and sharing of green production factors. [ABSTRACT FROM AUTHOR]

Concept factorization (CF) is an effective image representation algorithm, which has been widely used in dimension reduction, feature extraction, data mining and other fields. However, the traditional CF algorithm cannot make use of the limited label information, and fails to guarantee the sparse parts-based representation. Therefore, a novel semi-supervised CF with local coordinate constraint (SLCF) is proposed, which incorporates the local coor-dinates constraint and the limited label information into the CF. Specifically, SLCF enforces the learned coefficients to be sparse by using the local coordinate constraint, and the label constraint matrix can guarantee that the data points sharing the same label are mapped into the same label in the low-dimensional space, so the discriminative ability of different classes is improved. The efficient alternating iterative updating scheme is designed for optimizing SLCF and its convergence is theoretically provided. Numerical experiments on the COIL20, Yale B and MNIST databases demonstrate the effectiveness of proposed SLCF algorithm. Its clustering performance is better than other state-of-the-art algorithms.