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Acute kidney injury (AKI) can progress to renal fibrosis and chronic kidney disease (CKD), which reduces quality of life and increases the economic burden on patients. However, the molecular mechanisms underlying renal fibrosis following AKI remain unclear. This study tested the hypothesis that the Krüppel-like factor 4 (KLF4)/miR-101/Collagen alpha-1X (COL10A1) axis could inhibit epithelial-mesenchymal transition (EMT) and renal fibrosis after AKI in a mouse model of ischemia-reperfusion (I/R)-induced renal fibrosis and HK-2 cells by gene silencing, overexpression, immunofluorescence, immunohistochemistry, real-time quantitative PCR, Western blotting, dual-luciferase reporter assay, fluorescence in situ hybridization (FISH) and ELISA. Compared with the Sham group, I/R induced renal tubular and glomerular injury and fibrosis, and increased the levels of BUN, serum Scr and neutrophil gelatinase-associated lipocalin (NGAL), Col10a1 and Vimentin expression, but decreased E-cadherin expression in the kidney tissues of mice at 42 days post-I/R. Similarly, hypoxia promoted fibroblastic morphological changes in HK-2 cells and enhanced NGAL, COL10A1, Vimentin, and α-SMA expression, but reduced E-cadherin expression in HK-2 cells. These pathological changes were significantly mitigated in COL10A1-silenced renal tissues and HK-2 cells. KLF4 induces miR-101 transcription. More importantly, hypoxia upregulated Vimentin and COL10A1 expression, but decreased miR-101, KLF4, and E-cadherin expression in HK-2 cells. These hypoxic effects were significantly mitigated or abrogated by KLF4 over-expression in the HK-2 cells. Our data indicate that KLF4 up-regulates miR-101 expression, leading to the downregulation of COL10A1 expression, inhibition of EMT and renal fibrosis during the pathogenic process of I/R-related renal fibrosis. [ABSTRACT FROM AUTHOR]

Against the backdrop of climate change and the "dual carbon" goals, enhancing the ecological efficiency of cryospheric tourism is crucial not only for the high-quality development of the tourism industry itself but also for the protection of the ecological environment and the promotion of green sustainable development in the cryospheric region. In light of this, this study, taking climate change as its background and based on the perspective of carbon emission constraints, integrates multidimensional factors such as "climate change, carbon emission constraints, and cryospheric resources" into a unified measurement framework to construct a model for evaluating the ecological efficiency of tourism in the cryosphere. Specifically, the model considers inputs, expected outputs, and unexpected outputs. Subsequently, employing the super-efficiency slack-based measure (SBM) model, this study measures the tourism ecological efficiency (TEE) of three provinces (Xinjiang, Qinghai, Tibet) in the cryosphere from 2013 to 2021 and utilizes the Malmquist–Luenberger index and gray correlation model to reveal their dynamic changes, efficiency decomposition, and influencing factors. The results indicate that: (1) The overall mean of TEE in the cryosphere is between 0.2428 and 1.2142, Over the study period, the average annual growth rate and corresponding confidence interval were 14.74%, (−8.61%, 64.23%), showing a significant fluctuating growth trend. Among them, Xinjiang stands out, with its mean scores ranging from 0.2418 to 1.6229, surpassing the overall average level of the cryosphere. (2) During the study period, the overall dynamic efficiency of tourism ecology in the cryosphere increased by 21.54%, driven by the synergy of technological progress (TC), pure technical efficiency (PET), and scale efficiency (SE). For each province, the dynamic efficiency of tourism ecology has improved, but to varying degrees. (3) Regarding the driving factors of TEE in the cryosphere, each driving factor is closely related to TEE, ranked from large to small as follows: carbon emission structure, level of economic development, infrastructure, intensity of technological input, industrial structure, resource endowment, and environmental regulation. This article holds theoretical and practical significance for promoting the high-quality development of polar tourism and achieving synergistic progress between the economy and environment. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau (TP) serves not only as the "water tower" of Asia but also as an important source in the global atmospheric dust cycle. While our knowledge of modern dust activity and its impacts and interactions with climate change in the TP has greatly advanced in the past decades, the emission, transport, and deposition of dust on the geological time scale remains unclear. This study analyzed a 7.6‐m thick sedimentary sequence consisting of loess and sand from the Yarlung Tsangpo River (YTR) valley in the southern TP. The sequence chronology was established using nineteen K‐feldspar post‐infrared infrared stimulated luminescence (pIRIR) ages, which ranged from 47.11 ± 1.95 to 116.65 ± 5.55 ka in a general stratigraphical order. The dust sedimentation rate and sorting coefficient of grain size were used to reflect dust activity and near‐surface wind, respectively. The results indicated that dust activity in the southern TP is mainly regulated by the near‐surface wind intensity and follows the variation pattern of precession, although the waxing and waning of mountain glaciers also affect the amplitude of dust activity. This pattern is not consistent with the Greenland dust record, which follows the variation pattern of obliquity. Therefore, dust accumulation in the southern TP is concluded to be primarily controlled by the South Asian winter monsoon (SAWM) forced by precession, whereas dust accumulation in Greenland is closely related to the intensity of the high‐level westerlies forced by obliquity. Plain Language Summary: TP serves as an important source in the global atmospheric dust cycle, but the emission, transport, and deposition of dust in the geological time scale remain poorly understood. This study presents a Late Pleistocene record of dust activity based on a 7.6‐m thick sedimentary sequence from the YTR valley in southern TP. The results indicated that dust activity in southern TP is primarily regulated by the near‐surface wind intensity and follows the variation pattern of precession. When precession is large, the Northern Hemisphere's summer solstice is located at the aphelion, resulting in a lower Northern Hemisphere summer insolation (NHSI). Lower NHSI reduces winter temperature in the Northern Hemisphere, thereby increasing the temperature difference between the Indian Ocean and the TP. Consequently, wind over the YTR valley is strengthened, and the dust activity increases. Moreover, the variation amplitude of dust activity was revealed to be also affected by the waxing and waning of mountain glaciers. Dust accumulation was found to be asynchronous between the southern TP and Greenland. This asynchronous phenomenon is assumed to be related to the differential response of orbital parameters between the high‐level westerlies and near‐surface wind in southern TP. Key Points: Closely spaced luminescence dating for Late Pleistocene loess in the southern Tibetan Plateau is presentedDust activity follows the variation pattern of precession, despite mountain glaciers also affecting dust activity amplitudeAsynchronous variations of dust accumulation in the southern Tibetan Plateau and Greenland during the Late Pleistocene [ABSTRACT FROM AUTHOR]

Based on the data of Chinese A-share listed companies from 2010 to 2020, this article examines the driving effect of Digital Transformation of Corporations (DTC) on Total Factor Productivity (TFP) and selects Green Technology Innovation of Corporations (GTIC) as the mediating variable to test the mechanism of action of Digital Transformation of Corporations driving corporate TFP improvement. It is found that Digital Transformation of Corporations can significantly promote corporate TFP improvement; mechanism analysis shows that Digital Transformation of Corporations drives TFP improvement by promoting Green Technology Innovation of Corporations. [ABSTRACT FROM AUTHOR]

In order to analyze the variation characteristics and formation mechanism of environmental vibration caused by metro operation, field measurement of ground vibration and tunnel wall vibration are carried out along a metro line in Beijing. Vibration sample data of all trains in a whole day are analyzed statistically. And the main reasons for the discreteness of environmental vibration are summarized by comparing the vibration variety rules of different trains and different sections. The result shows as following. Firstly, the difference of vibration level at ground point can reach at most 14.6 dB, with a large degree of dispersion. Although the average value of twenty trains could meet the requirement of the standard prescribed limit, but there is still 30% ~ 50% of vibration values exceeding the standard prescribed limit. Secondly, the difference of vibration level at tunnel points reaches at most 22.1 dB, which is caused by the abnormal status of five vehicles in all trains on the day with the symptom of wheel irregularity. And the average value of maximum Z weighted vibration acceleration level (VLZmax) at tunnel wall points caused by them is 90.6 dB. Thirdly, vibration level at tunnel wall points between different sections induced by thesame vehicle is changed notably. And there is an important correlation with vehicle status. When the wheel is out of roundness visibly, the vibration level difference between different sections is changed more significantly. The maximum noise level can reach 10.7 dB, which is twice of 'normal vehicle', indicating that the deterioration of wheel state and track state will further change the wheel-rail interaction and aggravate the environmental vibration level. In addition, after wheel reprofiled of abnormal vehicles, the vibration level at ground point close to building is effectively reduced and all vibration values are reduced to less than 70 dB. [ABSTRACT FROM AUTHOR]