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Building height is important information in disaster management and damage assessment. It is also a key parameter in studies such as population modeling and urbanization. Relatively few studies have been conducted on extracting building height in rural areas using imagery from China's Gaofen-7 satellite (GF-7). In this study, we developed a method combining photogrammetry and deep learning to extract building height using GF-7 data in the rural area of Pingquan in northern China. The deep learning model DELaMa was proposed for digital surface model (DSM) editing based on the Large Mask Inpainting (LaMa) architecture. It not only preserves topographic details but also reasonably predicts the topography inside the building mask. The percentile value of the normalized digital surface model (nDSM) in the building footprint was taken as the building height. The extracted building heights in the study area are highly consistent with the reference building heights measured from the ICESat-2 LiDAR point cloud, with an R2 of 0.83, an MAE of 1.81 m and an RMSE of 2.13 m for all validation buildings. Overall, the proposed method in this paper helps to promote the use of satellite data in large-scale building height surveys, especially in rural areas. [ABSTRACT FROM AUTHOR]

Maglev vehicles apply the entire vehicle load uniformly onto bridges through levitation forces. In assessing the dynamic characteristics of the maglev train–bridge coupling system, it is reasonable to simplify the distributed levitation force as a concentrated force. This article theoretically derives the analytical response of bridge dynamics under the action of a single constant force and conducts numerical simulations for a moving single constant force and a series of equally spaced constant forces passing over simply supported beams and two-span continuous beams, respectively. The topic of discussion is the response of bridge dynamics when different degrees of force concentration are involved. High-precision displacement and acceleration sensors were utilized to conduct tests on the Shanghai maglev line to verify the accuracy of the simulation results. The results indicate that when simplifying the distributed levitation force into a concentrated force model, a frequency ratio can be used to analyze the conditions for resonance between the train and the bridge and to calculate the critical speed of the train; the levitation distribution force of a high-speed maglev vehicle can be simplified into four groups of concentrated forces based on the number of levitation frames to achieve sufficient accuracy, with the dynamic response of the bridge being close to that under distributed loads. [ABSTRACT FROM AUTHOR]

High-speed maglev system is a hot research topic nowadays in the field of high-speed ground transportation. Characteristics of the track irregularity of high-speed maglev system is quite different due to its contactless vehicle-rail relationship and segmented track compared with traditional railway. However, research on maglev track irregularity is still insufficient. This paper summarises, for the first time, the track inspection data collected on Shanghai Maglev Demonstration Line (Shanghai Line) since 2006, and describes the main filtering methods and parameters for acceleration and gap signals, taking into account the characteristics of maglev track. Track irregularity is then determined using the inertial measurement principle. The measured track spectrum on Shanghai Line calculated by the Welch method obeys a chi-square distribution with 2 degrees of freedom, indicating that different track qualities can be transformed by probability methods according to the research requirements. Based on the samples obtained over the past 15 years, and referring to the seven-parameter model of the railway system, a high-speed maglev track spectrum is obtained by the fitting method, parameters of which are obtained by applying the damped least squares method. Preliminary vehicle dynamic analysis is conducted utilising the inverted excitations derived from the measured spectrum of the Shanghai Line. [ABSTRACT FROM AUTHOR]

The article discusses a new technique called the Lubin method, also known as the lacing-up method, for vaginal rejuvenation to treat women with vaginal laxity. Vaginal laxity refers to a sensation of having a wide vagina during sexual intercourse. The traditional method of vaginoplasty involves tissue trimming, but the Lubin method is a minimally invasive technique that tightens the entire vagina without opening the vaginal wall. The study reports positive outcomes in terms of improved sexual function and no major complications. However, the study has limitations such as a small sample size and the absence of a comparative control group. [Extracted from the article]

Purpose: Radiotherapy (RT) is currently recognized as an important treatment for glioblastoma (GBM), however, it is associated with several challenges. One of these challenges is the radioresistance caused by hypoxia, whereas the other is the low conversion efficiency of the strongly oxidized hydroxyl radical (•OH), which is produced by the decomposition of water due to high-energy X-ray radiation. These factors significantly limit the clinical effectiveness of radiotherapy., Results: To address these limitations, we developed a highly stable and efficient nanoplatform (MnO 2 /Pt@BSA). Compared to MnO 2 @BSA, this platform demonstrates high stability, a high yield of oxygen (O 2 ), enhanced production of •OH, and reduced clearance of •OH. The system exhibited increased O 2 production in vitro and significantly improved oxygen production efficiency within 100 s at the Pt loading of 38.7%. Furthermore, compared with MnO 2 , the expression rate of hypoxia-inducible factor (HIF-1α) in glioma cells treated with MnO 2 /Pt decreased by half. Additionally, the system promotes •OH generation and consumes glutathione (GSH), thereby inhibiting the clearance of •OH and enhancing its therapeutic effect. Moreover, the degradation of the nanoplatform produces Mn 2+ , which serves as a magnetic resonance imaging (MRI) contrast agent with a T 1 -weighted enhancement effect at the tumor site. The nanoplatform exhibited excellent biocompatibility and performed multiple functions related to radiotherapy, with simpler components. In U87 tumor bearing mice model, we utilized MnO 2 /Pt nanocatalysis to enhance the therapeutic effect of radiotherapy on GBM., Conclusion: This approach represents a novel and effective strategy for enhancing radiotherapy in gliomas, thereby advancing the field of catalytic radiotherapy and glioma treatment., Competing Interests: The authors report no conflicts of interest in this work., (© 2024 Chen et al.)