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Tunnel waste constitutes a prevalent by‐product of highway construction in high‐altitude mountainous and hilly regions. Sulphide minerals exhibit a unique distribution pattern within the alpine hills. Consequently, tunnel excavation can disrupt the stability of these sulphide minerals, rendering the tunnel waste susceptible to generating secondary environmental hazards during stockpiling. This research delves into the migration and transformation dynamics of potential environmental pollutants in tunnel waste through geoenvironmental simulation techniques. Controlled variables were employed to simulate various conditions, including surface illumination, internal anaerobiosis, water content and aerobic environments. The study's findings indicate that the presence of pyrite in the waste stream primarily drives the secondary contamination of the tunnel waste. Pyrite within the slag tends to react and form sulphuric acid in the stockpile environment, thus creating an acidic milieu that exacerbates the release of existing contaminants. The emergence of an anaerobic environment and a photocatalytic system composed of Fe/Ti substances in the waste stream serves to further accelerate pollutant release. This study thoroughly investigates the primary causes of environmental pollution during the stockpiling of tunnel slag and assesses the potential environmental impact scenarios. The outcomes of this research offer substantial theoretical and empirical support for the management of slag generated during the tunnel construction process. [ABSTRACT FROM AUTHOR]

Nb modified SrFeNiMoNbO (SFNiMNb, x = 0, 0.05, 0.1, and 0.15) materials are synthesized by the one-step combustion method, and their characteristics are investigated. According to the X-ray diffraction (XRD), all samples present single perovskite structures and scanning electron microscope (SEM) results indicate that all samples possess uniform porous structures. Additionally, the electrode conductivity is improved by doping Nb on the B′ site of SFNiM. From the X-ray photoelectron spectroscopy (XPS) results, the ratios of Fe/Fe and Mo/Mo vary with the Nb content, which leads to the conductivity change of SFNiMNb materials. For all the samples, SFNiMNb exhibits the best electrochemical performance with the lowest polarization resistance of 0.11 Ω cm and the highest power density of 1260 mW cm 800 °C in humidified H. The results indicate that SFNiMNb is a promising type of candidate cathode for solid oxide fuel cells. [ABSTRACT FROM AUTHOR]

The urban heat island (UHI) poses a significant threat to urban ecosystems, human health, and urban energy systems. Hence, days with a relatively higher UHI intensity should be selected for UHI observation and analysis. However, there is still a lack in the method and criteria for selecting the typical meteorological days for UHI survey and simulation. In this study, field measurements were conducted based on Local Climate Zone (LCZ) schemes over a one-year period to assess the UHI behavior in Guangzhou, China. The relationship between the diurnal temperature range (DTR) and UHI intensity was evaluated and analyzed quantitatively under different meteorological conditions classified by precipitation. The average daily maximum UHI intensity ( UHII max ) during precipitation days was approximately 1.8 °C lower than that during non-precipitation days, confirming that precipitation has a negative effect on UHI development. The monthly DTR distribution was similar to the daily UHII max distribution, which was higher in autumn and winter, but lower in spring and summer. DTR has a significant linear correlation with the daily UHII max , with a Pearson's correlation coefficient of >0.7 and statistical significance of <0.001. Based on a quantitative evaluation of our results, we determined that 10 °C could be regarded as the appropriate DTR threshold to identify the meteorological conditions conducive to UHI development; the meteorological conditions exhibited a high daily UHII max in Guangzhou. This study provides a simple method to select typical meteorological days for UHI measurement and simulation, and a method to early-warning of intense UHI events based on weather forecasts. [ABSTRACT FROM AUTHOR]

Diabetic foot ulcers (DFU) are among the serious complications which are closely linked to diabetes mellitus. However, there is still a lack of accurate and effective standard prevention and treatment programs for DFU. In this manuscript, we have investigated the function of lncRNA cancer susceptibility candidate 2 (CASC2)/miR-155/hypoxia-inducible factor 1-alpha (HIF-1 α ) in the wound healing of DFU. We have analyzed lncRNA CASC2`s expression in the marginal tissues of ulcers in patients and mice with DFU. Additionally, the interaction relationship and mechanism between lncRNA CASC2, miR-155, and HIF-1 α were determined, which proved the effects of lncRNA CASC2/miR-155/HIF-1 α on fibroblasts apoptosis, proliferation, and migration. According to our study, the lncRNA CASC2's expression was low in the tissues of ulcers of DFU mice and patients. lncRNA CASC2's overexpression promoted fibroblasts migration, proliferation, and inhibited apoptosis and was beneficial for the healing of wounds, preferably in the DFU mice. In addition, lncRNA CASC2 directly targets miR-155 and HIF-1 α functions as miR-155's target gene. Overexpression of miR-155 abrogated the function of lncRNA CASC2. Similarly, HIF-1 α 's inhibition has reversed the effect of miR-155 downregulation on fibroblasts. In general, overexpression of lncRNA CASC2 facilitated wound healing through miR-155/HIF-1 α in DFU., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Minjie He et al.)