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Context: Diabetic retinopathy (DR) is a common complication of diabetes mellitus (DM). Circular RNAs (circRNAs) act as key regulators of DR development by regulating inflammation and angiogenesis. Objective: This study aimed to elucidate the function and mechanism of hsa_circ_0000047 in DR. Materials and methods: High glucose (HG) was used to induce human retinal microvascular endothelial cells (hRMECs) to construct a DR model in vitro. Qualitative real-time polymerase chain reaction (qRT-PCR) or western blotting were used to detected the levels of hsa_circ_0000047, miR-6720-5p, and CYB5R2 in DR and HG-indeced hRMECs. Cell functional experiments were performed to detect the change of viability, inflammation, migration, invasion, and angiogenesis of HG-induced hRMECs. Besides, the correlation between miR-6720-5p and hsa_circ_0000047/CYB5R2 was confirmed by luciferase assay and Pearson correlation analysis. Results: hsa_circ_0000047 and CYB5R2 were downregulated in DR, whereas miR-6720-5p was upregulated in DR. Cell functional experiments showed that hsa_circ_0000047 overexpression restrained viability, inflammation, migration, invasion, and angiogenesis of HG-induced hRMECs. Regarding mechanism, hsa_circ_0000047 could sponge miR-6720-5p to regulate CYB5R2 expression in hRMECs. Additionally, CYB5R2 knockdown reversed the effects of hsa_circ_0000047 overexpression on HG-induced hRMECs. Conclusion: Our study revealed that hsa_circ_0000047 alleviated inflammation and angiogenesis in HG-induced hRMECs by targeting the miR-6720-5p/CYB5R2 axis, which may be a novel biomarker for DR therapy. [ABSTRACT FROM AUTHOR]

With the increasing demand for transportation construction in coastal areas, tunnel safety research is becoming increasingly important. Previous studies take less account of the nonlinear wave and current action under the sloping seabed terrain. Furthermore, there are few researches on the additional deformation of shield tunnel lining caused by wave‐current dynamic pressure. In this paper, according to the interaction theory of Stokes third‐order nonlinear wave and uniform current and Biot's dynamic consolidation equation, the excess pore pressure response of sloping pure seabed under the wave‐current action is obtained. The excess pore pressure reflected by the tunnel is acquired using the seepage continuity condition on the permeable lining surface. Considering the residual excess pore pressure caused by the cumulative effect under the cyclic action of seepage force. Then the distribution law of seepage pore pressure around the shield tunnel in the sloping seabed under the wave‐current action is obtained based on the superposition principle. The displacement response of tunnel lining during the long‐term service period is obtained by combining the exponential decay model. Moreover, the accuracy of theoretical analysis is verified by experimental monitoring data and numerical simulation, and the hydraulic parameters, seabed parameters and tunnel parameters are analyzed. [ABSTRACT FROM AUTHOR]

With the increasing demand of transport construction in coastal areas, seabed instability around tunnels subjected to ocean waves and protection of the tunnels are becoming increasingly important. Current analytical solutions on the seepage field around subsea shield tunnels induced by waves are generally based on the impermeable lining, without considering the permeability. Furthermore, previous studies seldom take account of the influence of nonlinear wave loads under the sloping seabed terrain. For better tunnel stability, this paper presents a new set of analytical solutions for predicting Stokes wave-induced seepage pressure responses around a shield tunnel in a sloping seabed considering the influence of the permeable tunnel lining. The accuracy of the presented solutions is then verified by comparison with the numerical solution and experimental data, showing reasonable alignments. Moreover, parametric analyses are also performed to assess the influence of wave characteristics, seabed properties, and tunnel lining permeability on seepage pressure responses, in which the distribution of the excess pore pressure response outside the lining and excess pore pressure around the tunnel circumference is described in detail. In general, the analytical solutions provide an effective insight into the wave-induced seepage pressure response around a shield tunnel, which can serve as a credible theoretical basis in the preliminary design of tunnels. [ABSTRACT FROM AUTHOR]

Himawari-8, a geostationary satellite, is equipped with the Advanced Himawari Imager (AHI) sensor, which offers significant advantages for forest fire monitoring. This study proposes a weighted contextual fire detection algorithm (AHI_WFDA) that can apply to the AHI sensor as a global fire detection algorithm. Unlike the traditional pass-by screening algorithms, the algorithm takes into account the characteristics of different bands and assigns different weights and corresponding thresholds to the test conditions based on the bands' sensitivity to fire. To validate the algorithm's performance, we tested it on fires in five target areas. We regard MODIS data as the ground truth data and it was used as the benchmark for comparison with the AHI_WFDA , the Himawari-8 official product WLF, and the traditional spatial contextual algorithm (the reproduced SEVIRI algorithm). The results show that the AHI_WFDA significantly reduces the commission error rate compared to the WLF product. While our algorithm's accuracy rate is not superior to the SEVIRI algorithm, it detects more fire incidents correctly. Compared with the MODIS active fire product, the AHI_WFDA's omission error rate is about 63%. In contrast, the relative commission error rate is about 12%, which is in line with the results of some previous studies. In addition, we conducted detailed verification of our algorithm's results with the support of the Landsat series and Sentinel-2 data. The results show that the algorithm in this paper can effectively exploit the fire detection capability of AHI sensors and provide a new idea for the subsequent algorithms. [ABSTRACT FROM AUTHOR]