Optimized Antibiotic Resistance Genes Monitoring Scenarios Promote Sustainability of Urban Water Cycle.

Dissemination of antibiotic resistance genes (ARGs) in urban water bodies has become a significant environmental and health concern. Many approaches based on real-time quantitative PCR (qPCR) have been developed to offer rapid and highly specific detection of ARGs in water environments, but the complicated and time-consuming procedures have hindered their widespread use. Herein, we developed a facile one-step approach for rapid detection of ARGs by leveraging the trans-cleavage activity of Cas12a and recombinase polymerase amplification (RPA). This efficient method matches the sensitivity and specificity of qPCR and requires no complex equipment. The results show a strong correlation between the prevalence of four ARG markers (ARGs: sul1, qnrA-1, mcr-1, and class 1 integrons: intl1) in tap water, human urine, farm wastewater, hospital wastewater, municipal wastewater treatment plants (WWTPs), and proximate natural aquatic ecosystems, indicating the circulation of ARGs within the urban water cycle. Through monitoring the ARG markers in 18 WWTPs in 9 cities across China during both peak and declining stages of the COVID epidemic, we found an increased detection frequency of mcr-1 and qnrA-1 in wastewater during peak periods. The ARG detection method developed in this work may offer a useful tool for promoting a sustainable urban water cycle.

Fabrication of a Hot-Embossing Metal Micro-Mold through Laser Shock Imprinting.

As a technology for polymer surface fabrication, roll-to-roll hot embossing has been widely used because of its advantages, such as its low cost and high efficiency. However, the metal micro-mold is a major factor that determines the hot embossing of the polymer. In this study, a new metal micro-mold manufacturing method is proposed. The metal micro-mold is produced using laser shock imprinting (LSI) on the surface of metal foil. It has the characteristics of good thermal stability and high strength. During our LSI experiment, the strength of the mold increased after laser shocking. In this study, copper foils of different thicknesses were selected for LSI experiments. Through the analysis of the profile and forming depth of the microstructure, combined with the numerical simulation of the forming mechanism of copper foils with different thicknesses using ABAQUS software(Abaqus 2021), a copper foil with a flat back was selected as the final metal micro-mold. On this basis, copper molds with different microstructure shapes were created. Then, the mold was used in the hot-embossing experiment to manufacture the microstructure on the surface of polyethylene terephthalate (PET) and to study the fidelity and integrity of the molded microstructure. The deformation resistance of the copper mold under hot-embossing conditions was verified through a nano-indentation experiment. The final results show that the metal micro-mold produced via LSI had a high accuracy and molding stability and has potential applications in the field of roll-to-roll hot embossing.

[Environmental Behaviors of Plant Growth Regulators in Soil: A Review].

At present, plant growth regulators play an increasingly important role in global agricultural production. The average growth rate of global sales of plant growth regulators has been above 14% in the past decade. For many years, most plant growth regulators have been considered low-toxicity or slight-toxicity pesticides. However, recent studies have found that many plant growth regulators and their degradation products in the environment are potentially harmful to humans, animals, and plants. As the key factors to control the entering of plant growth regulators into the environment, the environmental behaviors of plant growth regulators in soil could make a significant influence on the risk of plant growth regulators to environmental safety. Therefore, it is critical to investigate the environmental behaviors of plant growth regulators in soil. This study systematically summarizes the environmental behaviors of plant growth regulators in soil from recent research, including the adsorption, desorption, hydrolysis, photolysis, and microbial degradation. Additionally, the factors affecting the environmental behaviors of plant growth regulators in the soil are discussed in detail. Moreover, the future research focus and direction to plant growth regulators are suggested.

Influence of pore water phase change on service performance for permeable pavement in Sponge City.

As the cornerstone of normal operation for Sponge City, the service performance of permeable pavement is directly related to the utilization rate of precipitation resources. However, the pore filling state (air, water and ice) of permeable pavement in Sponge City is easily affected by the service environment, especially low temperature. Thus, in the study, the influence of pore filling states and phase change processes on the service performance for permeable pavement were studied based on the models established on specimen section. Details of pore water phase change were visually displayed and described, and the strength variation of Marshall specimens after freeze-thaw cycle experiment also proved the rationality of simulation. Results show that the pore filling states in permeable pavement have different effects on the temperature field, and the influence of pore air on the temperature distribution for permeable pavement is greater than that of pore water (ice). In particular, weak positions between different pores are more susceptible to freezing stress, leading to stress concentration. Simulation results were also verified by macro experiments. Furthermore, the sustainable service performance of permeable pavement in Sponge City was inevitably affected. Therefore, the study results have certain significance for the development of permeable pavement in freezing and thawing regions, and are conducive to the wider application of Sponge City.