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To satisfy the ever‐accelerated demands for advanced engineering biomaterials with excellent physicochemical properties, injectable and recoverable dual‐network (DN) hydrogels based on poly(l‐lysine)‐graft‐4‐hydroxyphenylacetic acid (PLL‐g‐HPA) and Aga are constructed by simply mixing PLL‐g‐HPA/HRP and PLL‐g‐HPA/H2O2 in Aga through enzyme‐catalyzed cross‐linkage of PLL‐g‐HPA and temperature‐adjusted sol‐gel transition of Aga. The recoverable and injectable performances of hydrogels are attributed to the reversible sol‐gel transitional feature of Aga and enzymatically cross‐linked reaction of PLL‐g‐HPA. DN hydrogels have fast and adjusted gelation time, connective pore structure, superior formability, and good biocompatibility. The helically structural Aga network endows the hydrogels with good mechanical strength and superior stability in extreme condition. Schiff‐base effect between amino in skin tissues and carbonyl formed by the oxidation of phenol groups in hydrogel imparts the hydrogels to promising tissue attachment. Bursting pressure assay illustrates that the bursting pressure (34.5 ± 2.4 kPa) for 13.6% DN hydrogel is much higher than arterial blood pressure (16 kPa). The incorporated cationic PLL‐g‐HPA gives the hydrogels remarkable antibacterial ability, which effectively prevents the bacterial infection. In conclusion, the DN hydrogel with good cytocompatibility, inherently antibacterial ability, tissue adhesion, and excellent stability in extreme environment is probably able to become a promising candidate as potential wound dressings. [ABSTRACT FROM AUTHOR]

There are many important linkages between land, freshwater and oceans. Source-to-sea (S2S) management has been proposed to support environmental management that considers interests along the S2S continuum. This study takes the Bohai and Baltic seas as examples to analyse the legislation system, administrative structure and stakeholders of freshwater and marine management in China and the European Union and presents the related challenges and opportunities for S2S management. The results of this study can provide a basis for designing initiatives to support healthy ecosystems and sustainable green and blue economies, reduce the burdens on water-related ecosystems, and improve economic opportunities and livelihoods. [ABSTRACT FROM AUTHOR]

China is facing great challenges to balance its natural water resource use and eco-environment protection, especially in the north semi-arid region with large water consumption due to the rapid economic growth. This highlights the urgency to use water resource carrying capacity (WRCC) as a measure to maintain the sustainable development of the human and natural water system. Here, we used a coupled model based on the system dynamics and cellular automaton models to assess the WRCC under the critical value of water resource withdrawal ratio (40%) and its sustainability in the Yongding River watershed in Beijing-Tianjin-Hebei region, where the water use highly depends on river flow and nonrenewable groundwater resources. The analytical results showed that the current regional WRCC is severely overloaded due to strong human activities. The predicted results based on four scenarios, i.e., existing development, water saving, industrial restructuring, and integrated development schemes, showed that although the improvement of water saving and water use efficiency has mitigated the regional water shortage, evidenced by the increased WRCC, the water shortage would continue due to the increased water demand. Under the integrated development scenario, it will need at least additional 7.1 × 108 m3 water per year (Beijing: 2.5 × 108 m3, Tianjin: 0.8 × 108 m3, Hebei: 3.8 × 108 m3) via the water transfer project to maintain the sustainability in the next decades. Our research provides recommendations for reasonable water utilization and supplementation under the severe water crisis. [ABSTRACT FROM AUTHOR]

Astaxanthin (AST) is a natural compound with anti-inflammatory/immunomodulatory properties that has been found to have probiotic properties. However, the role and mechanism of AST in chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) are still not fully understood. The aim of this study was to evaluate the effect of AST on CP/CPPS and elucidate the mediating role of the gut microbiota. An experimental autoimmune prostatitis (EAP) mouse model was utilized to test the potential role of AST on CP/CPPS. Antibiotic cocktail (ABX) treatment and fecal microbiota transplantation (FMT) were used to elucidate the gut microbiota-mediated effects on AST. In addition, 16S rRNA gene sequencing and qRT-PCR analyses were used to analyze changes in the gut microbiota of EAP mice and CP/CPPS patients. Finally, the mechanism by which AST exerts a protective effect on CP/CPPS was explored by untargeted metabolomics and gut barrier function assays. Oral administration of AST reduced prostate inflammation scores, alleviated tactile sensitization of the pelvic region in EAP mice, reduced CD4+ T cell and CD68+ macrophage infiltration in the prostatic interstitium, and inhibited the up-regulation of systemic and localized pain/pro-inflammatory mediators in the prostate. After ABX, the protective effect of AST against CP/CPPS was attenuated, whereas colonization with fecal bacteria from AST-treated EAP mice alleviated CP/CPPS. 16S rRNA gene sequencing and qRT-PCR analyses showed that Akkermansia muciniphila in the feces of EAP mice and CP/CPPS patients showed a trend toward a decrease, which was associated with poor progression of CP/CPPS. In contrast, oral administration of AST increased the relative abundance of A. muciniphila , and oral supplementation with A. muciniphila also alleviated inflammation and pain in EAP mice. Finally, we demonstrated that both AST and A. muciniphila interventions increased serum levels of SCFAs acetate, up-regulated expression of colonic tight junction markers, and decreased serum lipopolysaccharide levels in EAP mice. Our results showed that AST improved CP/CPPS by up-regulating A. muciniphila , which provides new potentially effective strategies and ideas for CP/CPPS management. [ABSTRACT FROM AUTHOR]

Microfiber is a subgroup of microplastics and accounts for a large proportion of microplastics in aquatic environment, especially in municipal effluents. The purpose of the present study was to quantify microfiber shedding from three most populate synthetic textile fabrics: polyester, polyamide, and acetate fabrics. The results showed that more microfibers were released after washing with a pulsator laundry machine than a platen laundry machine. The greatest number of microfibers was released from acetate fabric, which was up to 74,816 ± 10,656 microfibers/m2 per wash, although microfibers were shed from all materials. Moreover, an increasing trend was found in the number of microfibers shedding from synthetic fabrics with the washing temperature increasing, and greater microfiber release occurred when washing fabrics with detergent rather than with water alone. The lint filter bag equipped with the pulsator laundry machine retained the longer microfibers (>1000 μm), but not the shorter microfibers (<500 μm) instead of releasing into the drainage system. Our data suggested that microfibers released during washing of synthetic fabrics may be an important source of microfibers in aquatic environment due to the increasing production and use of synthetic fabrics globally. Thus, more efficient filtering bags or other technologies in household washing machines should be developed to prevent and reduce the release of microfibers from domestic washing. Image 1 • The releasing of microfibers from three kinds of synthetic fabrics were evaluated. • More microfibers were released after washing with pulsator laundry machine. • The greatest number of microfibers were released from the acetate fabric. • The temperature and detergent promoted the releasing of microfibers. • The lint filter bag retained parts of microfibers with long size (>1000 μm). [ABSTRACT FROM AUTHOR]

With the rapid economic development in the past decades, industrialization and urbanization in China has also rapidly developed and will continue in the next decades. However, the regional water shortage has posed great challenges for the sustainable development of big cities especially in north China. Here, we used the water ecological footprint model combined with the system dynamic model to assess the water resource carrying capacity and its sustainability in Zhangjiakou City, a typical water shortage city in north China. The calculated results showed that irrigation was the largest water consumer in Zhangjiakou. There existed a clear gap between water supply and water consumption in this city and such a gap is demonstrated by the high water resource pressure index. Our predicted results based on the water resource ecological footprint and the system dynamic model showed that although the improving water use efficiency has relieved the regional water shortage pressure, the efficiency gained would be to a large degree offset by increased water demands due to the increasing economic development. The annual average water shortage in Zhangjiakou in 2007–2050 would be up to 8.53 × 108 m3, nearly half of the total local average annual water resource. To deal with the severe water shortage over the next three decades, great attention should be paid to scientific water resource managements and water pollution control. This research provides a long-term view of water resource pressure and provides recommendations for a sustainable water use under the rapid regional socioeconomic development. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional hydrogel sensor was constructed by the multi-reversible molecular interactions (MRMIs) including borate ester bonds, hydrogen bonds, and electrostatic interactions. • This report provides a new strategy for integrating excellent stretchability, adhesiveness, and sensing abilities into dynamically cross-linked hydrogels. • Integrating multi-functionalities of hydrogels into a sensing system opens a novel way for flexible sensors in multifunctional sensing applications. Construction of highly stretchable and sensitive flexible strain sensors is of great significance for wide applications in human–computer interaction, wearable devices, and electronic skins. However, it turned out to be not effortless to integrate the two seemingly contrary features of high stretchability and sensitivity into a system. Herein, we designed a nanocomposite conductive hydrogel (NCCH) composed of zwitterionic poly(HEAA-co-SBMA) polymers and lithium magnesium silicate (XLG) by means of multi-reversible molecular interactions (MRMIs) including borate ester bonds between polyHEAA and borax, hydrogen bonds, and polySBMA-XLG-based electrostatic interaction, endowing the NCCH with enhanced mechanical, self-healing, adhesive, biocompatible, and sensing performances. The MRMI method enabled NCCHs to obtain an excellent stretchability (∼1080 %)/compressibility (∼98.5 %), a tensile strength of ∼ 0.06 MPa, a good self-healing with a fracture strain recovery of 90.5 %, and a strong adhesion on various hard and soft substrates (e.g. a adhesive shear force of 60 kPa to pigskin tissues). Besides, the integration of zwitterionic polySBMA and conductive XLG promoted charge transfer. by optimal ioinic channels. Based on these outstanding strengths, the NCCHs were farther rationally fabricated as multifunctional strain sensors with remarkable sensing stability for fast and accurately detecting strain/pressure-induced deformation, joint motions, and animal heartbeats. Notably, the excellent self-healing property of NCCH sensors can facilitate their long-period usage and complete recyclability for avoiding wastes. The new MRMI-based NCCH sensor without any conductive additives is deemed to provide a new strategy for broadening their multifunctional strain sensor and healthcare monitoring applications. [ABSTRACT FROM AUTHOR]

Coupling vortex-induced vibration (VIV) and galloping is a promising strategy to enhance the performance of VIV-based piezoelectric wind energy harvesters (PWEHs). In this paper, we proposed to employ upstream bluff bodies to induce the wake of a downstream semicircular wall to evolve from VIV to galloping, where a PWEH was mounted to the semicircular wall. The effects of wind speed, spacing ratio, and cross-section of upstream bluff body on the output performance of the PWEH were examined experimentally. The results showed that an appropriate spacing ratio was required to ensure the occurrence of the wake evolution. Qualitative analyses revealed that the Strouhal number of upstream bluff body could tune the evolving behaviors of the semicircular wall, and the separation distance between VIV and galloping decreased with Strouhal numbers except for the cases in the near wake. The upstream circular and square cylinders performed better in driving the evolution than the trapezoidal and triangular cylinders. The maximum energy conversion efficiency improvement of 38.4% was achieved at a wind speed of 4.0 m/s with a spacing ratio of 10.0 for the upstream square cylinder, compared to that without an upstream bluff body. The findings provide beneficial guidance for developing efficient VIV and galloping coupled energy harvesters. [Display omitted] • Employing various upstream bluff bodies' wakes to enhance energy harvesting from VIV. • The semicircular wall exhibited the detailed evolution from VIV to galloping. • An appropriate spacing ratio was required to induce the evolution occurring. • Circular and square cylinders performed better than the other two cylinders. • Maximum energy conversion efficiency improvement of 38.4% was achieved at 4.0 m/s. [ABSTRACT FROM AUTHOR]

This study focused on preparing sea urchin palladium-copper nanospines (PdCuAu NAs) using a one-step reduction method. PdCuAu NAs is a highly branched nanomaterial composed of nanospines, and its unique structure and trimetallic composition give it excellent Fenton catalytic activity and photothermal properties. The characterization of PdCuAu NAs was carried out using SEM, XPS, and UV-Vis techniques. Under near-infrared light, PdCuAu NAs were quickly heated to 50 ℃. Compared to traditional photocatalysts, PdCuAu NAs showed better Fenton catalytic activity in the degradation of organic dyes such as MB. Furthermore, it exhibited good photothermal stability and reusability after multiple thermal cycles and repeated use. Thus, the results showed that PdCuAu NAs had a good degradation effect on organic wastewater. • The PdCuAu NAs could mediate a series of Fenton-like reaction. • The generated •OH could effectively degrade colored organic pollutant. • The PdCuAu NAs have low toxicity at relative high concentration (2.0 mg/mL). • The PdCuAu NAs can improve the Fenton catalytic efficiency via synergetic photothermal effects. [ABSTRACT FROM AUTHOR]

The single-doped Cu+ glass obtained by ion exchange preparation process was studied. The exchange depth of copper ions in the glass reached 50 μm–150 μm (prepared at 370 °C–530 °C, 16 h). XPS and Raman testing showed that the glass network polymerization degree of the thin glass (thickness 0.2 mm) was lower than that of the thick glass (thickness 2 mm), and the optical alkalinity of the thin glass surface was lower than that of the thick glass. The proportion of monovalent Cu ions coordinated in octahedra in the thin glass sheet was higher than that in the thick glass sheet. PL studies had shown that under the condition of ion exchange at 370 °C for 16 h, the fluorescence intensity and fluorescence quantum efficiency of thin glass samples were higher than those of thick glass samples. The fluorescence quantum efficiency of thin glass samples reaches 56.88%, and they also have good thermal stability. [ABSTRACT FROM AUTHOR]

Harvesting energy from ambient air is crucial for sustaining the operation of low-power electronic devices under autonomous conditions. In this study, a specially designed semicircular wall with a thin splitter plate was proposed, behind which the wake exhibited evolution from vortex-induced vibration (VIV) to galloping. Benefiting from this peculiar flow pattern, a piezoelectric energy harvester placed in the cylinder wake can perform well under variable wind speed conditions. The effects of aspect ratio (α) and nondimensional afterbody length (l *) of the semicircular wall on the energy harvester's performance were experimentally examined. The results showed that the aspect ratio was highly correlated with the modes of flow-induced vibrations. When 2/3 ≤ α ≤ 4/3 and l * = 1/2, the harvester experienced VIV, transition from VIV to galloping, and galloping with a continuously increasing wind speed. Frequency analysis further revealed that the resonance force and lift instability caused by vortex shedding of the semicircular wall might arise almost simultaneously, with the latter serving as the driving factor in the evolution from VIV to galloping. It is also found that the harvester operated efficiently at wind speeds of 1.0–12.0 m/s, and an appropriate nondimensional afterbody length was required to achieve high-level power outputs. These findings provide beneficial suggestions for developing the coupled VIV-galloping energy harvesters. [Display omitted] • A semicircular wall with a thin splitter plate is designed to harvest wind energy. • Semicircular wall wake exhibits evolution from vortex-induced vibration to galloping. • The wall's aspect ratio can easily tune the modes of flow-induced vibrations. • An appropriate afterbody length is required to achieve high-level power output. • The designed energy harvester operates efficiently at wind speeds of 1.0–12.0 m/s. [ABSTRACT FROM AUTHOR]