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Based on the panel data of 283 prefecture-level cities in China from 2010 to 2021, this paper takes the pilot policy of “Broadband China” as a natural experiment to evaluate the impact of digital infrastructure construction on urban ecological welfare performance and its mechanism by using a progressive difference–difference model. The results show that China’s digital infrastructure construction will significantly reduce the performance of urban ecological welfare. Through the analysis of input and output, it is found that the construction of digital infrastructure can significantly reduce resource consumption and increase welfare output, especially economic welfare, but at the level of environmental pollution, it will significantly increase the discharge of industrial wastewater, which may be the main reason for the negative effect of digital infrastructure construction. Through the group analysis, it is found that the overall negative impact of digital infrastructure construction on ecological welfare performance may be caused by the ecologically fragile western region and the unreasonable industrial structure. Through the adjustment model, it is found that innovation investment can positively regulate the negative impact of digital infrastructure on ecological welfare performance. The grey model (GM) is further used to forecast the data for 2022–2025, and it is found that while the negative impact of digital infrastructure is decreasing, it is still significant. This study provides empirical evidence for accurately understanding the effect and mechanism of digital infrastructure construction on ecological welfare performance.

An iterative correction method for the stress release coefficient, leveraging numerical simulation, has been innovatively developed to address the significant error issues associated with the blind-hole method in high-stress residual stress testing of steel structures. This method effectively reduces measurement error in high residual stress regions through a discriminant iteration process. The finite element analysis technology was employed to accurately simulate the blind-hole method’s test process, and additionally, Python was utilized for customizing the secondary development of ABAQUS software, thereby automating and optimizing the method. When compared with simulation and experimental data from the welding process, the efficiency, accuracy, and reliability of the correction method have been verified. The proposed method eliminates the need for tedious calibration experiments inherent in traditional methods, significantly enhancing the test’s automation level and convergence speed, and ensuring measurement accuracy, which provides an innovative solution for the accurate evaluation of residual stress in steel structures.

Discus fish, Symphysodon spp., have a unique parental care strategy where the fry feed on their parents’ skin mucus after hatching. Here, lipidomics was employed to compare the skin mucus lipid profiles of male or female discus fish during parental and non-parental care. By multivariate statistical analysis, clear separations were found between parental and non-parental female and between parental and non-parental male discus. In the comparison between female discus in the parental and non-parental stages, a total of 107 differentially expressed lipids (DELs) were observed, of which 23 showed increased levels during parental care. For male discus, a total of 108 DELs were found, of which 46 displayed increased levels during parental care. The main DELs were phosphatidyl ethanolamine and phosphatidylinositol, mainly involved in arachidonic acid and sphingolipid metabolism pathways. Further, by comparing parental male and female discus, we found 47 DELs involved in the glycerophospholipid metabolism pathway. Diglyceride showed a higher concentration in the skin mucus of parental females, while phospholipids showed a higher level in that of parental males. Our results revealed changes in the skin mucus lipid profiles of discus fish during parental care, as well as sex-dependent differences between parental fish.

The production mode of “high input, high yield and high waste” in the agricultural system poses a serious threat to the environment and the quality of agricultural products. Accelerating the adoption of green agricultural technology (GAT) by farmers is an emergency measure. However, according to microsurvey data, many farmers give up GAT within a year after adopting it. The implementation of this measure has been anticlimactic. Based on a survey of 1138 kiwi growers in Shaanxi Province, China, this paper builds a theoretical model and conducts empirical exercises to gain insight into the effects of perceived value, government support and their interaction with kiwi growers’ sustainable application of GAT. We find that perceived value and government support have a significant impact on the sustainable application of GAT. Government support plays a moderating role in the influence of perceived value on the sustainable application of GAT. Furthermore, in order to overcome the potential endogeneity problem caused by the two-way causal relationship between subjective variables, “owning a smartphone” was selected as the instrumental variable. The 2SLS model was used for endogeneity analysis, and the OLS model was used for the robustness test. This paper discusses the relevant theories and policy implications of environmental management.