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The Sichuan-Yunnan diamond block is a significant region of material flow from the Tibetan Plateau. However, its northwest electrical boundary remains undefined. Our study conducted a magnetotelluric profile from Chazha to Luomai across the geological boundary of the Sichuan-Yunnan block in its northwest sector. Using the nonlinear conjugate gradient three-dimensional inversion method, we obtained the deep electrical structure across the northern part of the block. Our findings reveal distinct segmental characteristics in the electrical structure along the profile. Marked by a high-resistivity zone along the Dedeng-Batang-Riyu fault, two high-conductivity layers exist in the upper-middle crust of the southwestern and central sections of the profile, at depths of 5–20 km and 10–30 km, respectively. Thus, our study suggests that the northwest boundary of the Sichuan-Yunnan diamond block, contrary to previous studies that considered it a transitional boundary, is located at the Dedeng-Batang-Riyu fault. Here, the boundary is a high-resistivity barrier, electrically isolating the Qiangtang block in the southwest from the Sichuan-Yunnan block in the northeast. The two significant high-conductivity zones in the upper-middle crust appear within the block's interior, contrasting with previous assumptions of lower crustal flow. [ABSTRACT FROM AUTHOR]

Solid waste materials (SWM) are commonly used in the preparation of building materials due to their structural characteristics and chemical composition. Pervious concrete (PC) is a green infrastructure material that offers advantages such as reducing surface runoff and purifying water quality, making it an important component of sponge cities. This study aims to investigate the physical properties and micro-structure of PC prepared from various SWM and determine the optimal mix proportion. In this study, three common SWM, including muck, steel slag (SS) and fly ash (FA), are used as raw materials. The chemical composition and physical properties of SWM are analyzed. A five-level and five-factor test scheme is developed using the orthogonal test method. This scheme considers the target porosity, water–cement ratio, muck content, SS content, and FA content as variables. The mechanical properties and permeability of PC, including compressive strength, porosity and permeability coefficient are evaluated. The internal structure of PC is observed using a scanning electron microscope (SEM). The results indicate that the optimal mix proportion for preparing PC is determined through efficiency coefficient method analysis: target porosity of 25%, water–cement ratio of 0.36, muck content of 10%, SS content of 10%, and FA content of 12.5%. The corresponding performance indicators of the PC sample are measured as follows: porosity of 24.67%, compressive strength of 15.78 MPa, and permeability coefficient of 2.23 mm/s. This study provides valuable insights for the rapid and flexible batching and performance optimization research of PC based on SWM. [ABSTRACT FROM AUTHOR]

Background: Vessel segmentation in fundus photography has become a cornerstone technique for disease analysis. Within this field, Ultra-WideField (UWF) fundus images offer distinct advantages, including an expansive imaging range, detailed lesion data, and minimal adverse effects. However, the high resolution and low contrast inherent to UWF fundus images present significant challenges for accurate segmentation using deep learning methods, thereby complicating disease analysis in this context. Methods: To address these issues, this study introduces M3B-Net, a novel multi-modal, multi-branch framework that leverages fundus fluorescence angiography (FFA) images to improve retinal vessel segmentation in UWF fundus images. Specifically, M3B-Net tackles the low segmentation accuracy caused by the inherently low contrast of UWF fundus images. Additionally, we propose an enhanced UWF-based segmentation network in M3B-Net, specifically designed to improve the segmentation of fine retinal vessels. The segmentation network includes the Selective Fusion Module (SFM), which enhances feature extraction within the segmentation network by integrating features generated during the FFA imaging process. To further address the challenges of high-resolution UWF fundus images, we introduce a Local Perception Fusion Module (LPFM) to mitigate context loss during the segmentation cut-patch process. Complementing this, the Attention-Guided Upsampling Module (AUM) enhances segmentation performance through convolution operations guided by attention mechanisms. Results: Extensive experimental evaluations demonstrate that our approach significantly outperforms existing state-of-the-art methods for UWF fundus image segmentation. [ABSTRACT FROM AUTHOR]

Adolescent idiopathic scoliosis (AIS), which typically occurs in patients between the ages of 10 and 18, can be caused by a variety of reasons, and no definitive cause has been found. Early diagnosis of AIS or timely recognition of progression is crucial for the prevention of spinal deformity and the reduction of the risk of surgery or postponement. However, it remains a significant challenge. The purpose of this study is to develop an easy-to-use, non-invasive, and portable method for early diagnosis of AIS. A new framework of moving entropy-based computer vision method is presented, which can determine the severity of AIS by analyzing patients' walking videos. First, Alphapose system and direct linear transformation method are employed to estimate 3D keypoint coordinates. Then, the joint angle-based and joint distance-based dynamic network are constructed. Based on these works, the new measures called moving angle entropy and moving edge-weighted graph entropy are proposed and fused using canonical correlation analysis. Finally, the power spectral exponents of entropy sequences are calculated and used in recognizing the severity of AIS. A comparison with healthy subjects and statistical analysis for entropy values can provide effective information for quantifying AIS. The recognized results of our proposed method were also comparable with the clinical diagnosis of Cobb angle from imaging by a certified clinician. [ABSTRACT FROM AUTHOR]

As the third largest source of energy in addition to carbohydrates and proteins, lipids provide the body with more than twice as much energy as carbohydrates and proteins and are the accumulated "fuel bank" of the body. They are widely stored in animals, plants and microorganisms and are effectively extracted for dietary use by improved and novel technologies. Under the pressure of the current environment, we should immediately look for new strategies to improve or develop dietary lipids that are compatible with the development of the future food industry, in order to mitigate the environmental and climatic degradation caused by the lipid-producing activities of the animal husbandry industry, to avoid the contradiction between the demand for high quality of human beings and the strain on the resources, and to reduce the health risks caused by saturated fats and trans-fats in meat products. At present, workers concerned are opening up new avenues for the future edible lipids, for example, researches into fat and oil substitutes, the use of biotechnology in lipids and the value-added reuse of waste products is in full swing. The article therefore began with a detailed overview of the known lipids available, understanding their origins and the ways in which they were classified by region. Secondly, possible trends and potential strategies for dietary lipids for use in future foods were presented. Finally, constructive comments are made on the problems and challenges that may be encountered in the research and subsequent industrialization process. [ABSTRACT FROM AUTHOR]

With the large-scale construction of urban rail transit viaducts in China, the noise problem caused by trains traversing these sections has become increasingly prominent and a key technical challenge that restricts the sustainable development of rail transit. There are two main noise sources when trains pass on rail transit viaducts, namely, wheel-rail noise (WRN) and bridge-borne noise (BBN). However, most of the existing rail transit viaduct noise prediction models consider only a single noise source. In this study, a total noise prediction model incorporating both WRN and BBN was established using the finite element method (FEM), the boundary element method (BEM), and statistical energy analysis (SEA). The viaducts of Wuhan Metro Line 2 were selected as the research object, and noise tests of trains passing on the viaducts were carried out to validate the total noise prediction model. Based on the validated model, the spatial distribution characteristics and attenuation laws of the total noise were investigated, along with the influence of train speed on the total noise. The results show that the prediction model accurately simulated the total noise caused by trains passing on viaducts. When a train passed on the viaduct at a speed of 60 km/h, the total noise near the viaduct reached 88 dB(A) and decreased with the increase in the distance; at 120 m from the track centerline, the total noise decreased to less than 57 dB(A). As the distance increased, the total noise diminished across the entire frequency spectrum. Notably, low-frequency noise decayed at a slower rate than high-frequency noise. As the distance from the track centerline doubled, the total noise decreased by about 4.23 dB(A). The total noise increased with train speed. When the train speed doubled, the total noise at 30 m and 120 m from the track centerline increased by 6.32 dB(A) and 5.96 dB(A), respectively. The reason for this phenomenon is that the wheel-rail forces increase with the increase in train speed. This study will have important guiding significance and scientific value for the sustainable development of urban rail transit. [ABSTRACT FROM AUTHOR]

During the in-service use of porous asphalt pavement, debris can clog internal voids, impacting both its long-term performance and maintenance costs. Thus, understanding the clogging mechanism is crucial. This study introduces a novel approach to simulate clogging behavior by coupling the discrete element method (DEM) and computational fluid dynamics (CFD) to analyze various particulate clogging scenarios. The simulations included the effects of vehicle vibrations, the impact of rainwater seepage and their combination. The simulation results reveal that both vibration and rainwater significantly reduce clogging material mass, improving pavement permeability. Particles sized between 0.15 mm and 1.18 mm were identified as the most likely to cause clogging, with the tendency increasing alongside seepage velocity. This methodology provides a comprehensive framework for analyzing real-world clogging mechanisms and offers valuable insights for designing more durable and sustainable porous asphalt pavements. Highlights: The asphalt pavement was reconstructed based on CT 3D, and the calculation accuracy was improved by CFD-DEM coupling simulation. For the first time, the vibration load and rainfall effect of a porous asphalt pavement during service were numerically simulated. The blockage attenuation rate was proposed and derived to characterize the quality change of clogging. The maximum clogging attenuation rate of vehicle vibration load is 7.8%, and the maximum rainfall effect is 14.6%. [ABSTRACT FROM AUTHOR]

High temperature aging treatment was first conducted on the rejuvenated directionally solidified superalloy to simulate the re-service aging damage of turbine blades and the virgin directionally solidified superalloy respectively. Then re-service aging stability of γ′ phase in the virgin and rejuvenated directionally solidified superalloy was compared and analyzed, and the effect of different rejuvenation parameters on γ′ phase microstructure of the rejuvenated directionally solidified superalloy after the same re-service aging time was studied. The results show that although rejuvenation heat treatment can effectively restore creep microstructure to a nearly ‘‘as-new’’ condition, the re-service aging stability of γ′ phase in the rejuvenated directionally solidified superalloy is worse than that of the virgin directionally solidified superalloy, which is attributed to the decomposition of MC carbide. The rejuvenation heat treatment parameters have a great influence on re-service aging stability of the rejuvenated directionally solidified superalloy. The re-service aging rate of γ′ phase in the rejuvenated directionally solidified superalloy becomes higher, the higher the solution temperature, the shorter the holding time and the greater the cooling rate after solution higher. However, the increased primary aging temperature and holding time cause the decrease of the re-service aging rate of γ′ phase in the rejuvenated directionally solidified superalloy. The second aging condition has no obvious effect on the re-service aging stability of γ′ phase.