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Soil remediation industry plays an important role in promoting "double carbon" action and improving soil carbon sink capacity. However, the concealment, persistence and irreversibility of heavy metal pollution make the soil heavy metal pollution in China continuously accumulate, hindering the realization of "double carbon" goal. Immobilized microbial technology is used as one of the bioremediation methods. This technology can reduce the energy consumption and secondary pollution produced by traditional physical and chemical methods in the remediation process. This technology can also improve microbial density and maintain microbial activity. Therefore, it has a broad development prospect in the remediation of heavy metal contaminated soil. This paper firstly introduced the classification of immobilized microbial technology from three perspectives of immobilization methods, carrier types, and microbial species. Then the mechanisms of heavy metal pollution remediation by this technology were summarized. According to different application situations, the selection of carriers and microorganisms is of great importance. So, this paper also summarized the research development status of immobilized microbial technology in the last five years. Studies have shown that this technology can effectively remediate heavy metal contaminated soil. New carriers and new microorganisms have been developed to satisfy a variety of applications. The technology can also be combined with phytoremediation technology to achieve a more low-carbon remediation effect. Considering the future development potential of this technology, this paper also proposes the development direction of immobilized microbial technology. It is expected to provide a reference for the development of immobilized microbial technology for remediation of heavy metal contaminated soil.

This letter presents a model based on the Cramér–Rao bound theory for calculating the theoretical lower limit of imaging resolution of microwave computational imaging aided by re‐configurable metasurface. The model takes into account two crucial parameters: the signal‐to‐noise ratio and the number of measurements in the imaging process. By simultaneously considering the signal‐to‐noise ratio and the number of measurements, as well as other parameters, the model allows for a comprehensive assessment of the imaging resolution of the imaging system. In addition, both position estimation and intensity estimation are considered, and a new composite statistical resolution concept is proposed, which is more suitable for microwave computational imaging. [ABSTRACT FROM AUTHOR]

Wrinkles are urgent problems to be solved in the process of hot diaphragm preforming. Inter-ply slipping resistance is one of the causes of wrinkles. In this paper, based on the vertical inter-ply slipping test system, the inter-ply slipping behaviors of carbon fiber-reinforced epoxy resin composite prepregs were characterized. The mechanism of wrinkles caused by inter-ply slipping resistance was analyzed. According to the different characteristics expressed by the fiber and resin during the slip process, the inter-ply slipping behaviors of the prepregs were divided into three stages. The effect of temperature on the inter-ply slipping stresses was shown. The temperature will affect the viscosity of the prepregs. When the viscosity of the prepregs is low, the inter-ply slipping resistance will decrease. Based on the Coulomb friction law and the hydrodynamic equation, the inter-ply slipping kinetic equation of the prepregs was established. The inter-ply slipping kinetic equation was introduced into the ABAQUS main program by the 'vfriction' subroutine. The introduction of inter-ply slipping dynamics improved the accuracy of predicting the shape and position of wrinkles. [ABSTRACT FROM AUTHOR]

Structured meshes are becoming increasingly popular as a discretization technique in industries where solution accuracy is of paramount importance. However, generating structured meshes directly on the model surface presents a challenge. Consequently, many researchers are now exploring mapping methods for structured mesh generation. In this context, parameterization algorithms are vital as they map the model surface from 3D space to a 2D parametric domain. Existing parameterization algorithms, despite their advancements, still face limitations in preserving symmetry information from the input model. To address this issue, we propose a symmetry preserving parameterization algorithm based on geometric constraint. This algorithm utilizes plane reflection symmetry transformation to identify the main symmetry plane of the model and calculate the symmetry factor. Based on the fixed points and the symmetry factor, a conformal parametric symmetry plane is obtained. Furthermore, we develop a surface structured mesh generation system to provide engineers with a tool that can rapidly generate meshes. Experimental results demonstrate that our proposed algorithm achieves higher quality results compared to other parameterization algorithms. [ABSTRACT FROM AUTHOR]

In recent years, more and more people are applying Convolutional Neural Networks to the study of sound signals. The main reason is the translational invariance of convolution in time and space. Thereby the diversity of the sound signal can be overcome. However, in terms of sound direction recognition, there are also problems such as a microphone matrix being too large, and feature selection. This paper proposes a sound direction recognition using a simulated human head with microphones at both ears. Theoretically, the two microphones cannot distinguish the front and rear directions. However, we use the original data of the two channels as the input of the convolutional neural network, and the resolution effect can reach more than 0.9. For comparison, we also chose the delay feature (GCC) for sound direction recognition. Finally, we also conducted experiments that used probability distributions to identify more directions.

This document summarizes a study on the role of γδ17 T cells in radiation pneumonitis (RP), a side effect of radiation therapy. The study found that a specific subset of γδ17 T cells interact with neutrophils through the IL17A axis in the late phase of RP. These γδ17 T cells showed a terminally exhausted phenotype and likely expand from tissue-resident memory cells. The study also identified the IL17 response signature as a downstream target of γδ17 T cells and found that neutrophils exhibited the highest IL17 response signature activity. The findings suggest that targeting the γδ17 T/neutrophil axis may be a potential therapeutic approach for RP. The document also provides a summary of the biological process of RP in the early and late phases, highlighting the role of cell death, DAMPs release, neutrophil recruitment, and the activation of γδ17 T cells and mature neutrophils. The study provides insights into RP pathogenesis and suggests new therapeutic avenues. [Extracted from the article]

The investigation of the in-plane shear behavior of prepreg is crucial for understanding the generation of wrinkles of preforms in advanced composite manufacturing processes, such as automated fiber placement and thermoforming. Despite this significance, there is currently no standardized test method for characterizing uncured unidirectional (UD) prepreg. This paper introduces a ±45° off-axis tensile test designed to assess the in-plane shear behavior of UD carbon fiber-reinforced epoxy prepreg (CF/epoxy). Digital image correlation (DIC) was employed to quantitatively track the strains in three dimensions and the shear angle evolution during the stretching process. The influences of the temperature and stretching rate on the in-plane shear behavior of the prepreg were further investigated. The results reveal that four shear characteristic zones and wrinkling behaviors are clearly distinguished. The actual in-plane shear angle is significantly lower than the theoretical value due to fiber constraints from both the in-plane and out-of-plane aspects. When the off-axis tensile displacement (d) is less than 15.6 mm, the ±45° specimens primarily exhibit macroscale in-plane shear behavior, induced by interlaminar interface shear between the +45° ply and −45° ply at the mesoscale. The shear angle increases linearly with the d. However, when d > 15.6 mm, fiber squeezing and wrinkling begin to occur. When d > 29 mm, the in-plane shear disappears in the completely sheared zone (A). The reduction in the resin viscosity of the CF/epoxy prepreg caused by increased temperature is identified as the primary factor in lowering the in-plane shear force resistance, followed by the effect of the increasing resin curing degree. Higher shear rates can lead to a substantial increase in shear forces, eventually causing cracking failure in the prepreg. The findings demonstrate the feasibility of the test method for predicting and extracting uncured prepreg in-plane shear behaviors and the strain-rate and temperature dependency of the material response. [ABSTRACT FROM AUTHOR]