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Enhancing information security has become increasingly significant in the digital age. This paper investigates the concept of physical layer security (PLS) within a relay-aided power line communication (PLC) system operating over a multiple-input multiple-output (MIMO) channel based on MK model. Specifically, we examine the transmission of confidential signals between a source and a distant destination while accounting for the presence of multiple eavesdroppers, both colluding and non-colluding. We propose a two-phase jamming scheme that leverages a full-duplex (FD) amplify-and-forward (AF) relay to address this challenge. Our primary objective is to maximize the secrecy rate, which necessitates the optimization of the jamming precoding and transmitting precoding matrices at both the source and the relay while adhering to transmit power constraints. We present a formulation of this problem and demonstrate that it can be efficiently solved using an effective block coordinate descent (BCD) algorithm. Simulation results are conducted to validate the convergence and performance of the proposed algorithm. These findings confirm the effectiveness of our approach. Furthermore, the numerical analysis reveals that our proposed algorithm surpasses traditional schemes that lack jamming to achieve higher secrecy rates. As a result, the proposed algorithm offers the benefit of guaranteeing secure communications in a realistic channel model, even in scenarios involving colluding eavesdroppers. [ABSTRACT FROM AUTHOR]

Highlights • The strain presents a parabolic or linear increase with the times of freeze-thaw cycles. • Proportion of 2:5:3 of recycled construction waste mixtures has better mechanical properties. • Maximum porosity occurs after 10 freeze-thaw cycles. • Fractal dimension of construction waste increases gradually with the increased freeze-thaw cycles. • Order between particles of construction waste decreases with the increased freeze-thaw cycles. Abstract To investigate the effect of freeze-thaw cycle on the mechanical and porosity properties of the recycled construction waste mixtures, a series of freeze-thaw cycles, cyclic loading and unloading and CT scan tests were carried out on four proportions of samples, including the brick, concrete and mortar slag. The testing results reveal that the strain presents a parabolic or linear increase with the increasing freeze-thaw cycles. Hence, the cumulative plastic strain and resilience modulus show a linear relation to freeze-thaw cycles. Reducing the brick slag content and increasing the concrete slag content can increase the modulus of resilience. In addition, the maximum porosity occurs after 10 freeze-thaw cycles. The minimum porosity within and between layers appears in 0 and 20 freeze-thaw cycles, respectively. The fractal dimension of the construction waste mixture increases gradually and the order between the particles decreases with the increase of freeze-thaw cycles. The proportion of 2:5:3 of recycled construction waste mixtures has the better mechanical properties under freeze-thaw cycles and can be used as subgrade filling. Moreover, effective utilization of construction waste can reduce the environmental pollution and promote sustainable infrastructure. [ABSTRACT FROM AUTHOR]

• Three evaluation indicators (i.e., size, contour shape and angularity) are proposed. • Classification method of renewable construction waste particles was determined. • Three particle contact structures between particles were obtained. • Contact forms between particles are analyzed considering the particle breakage. Diversity in microscopic particle morphology and the particle contact between geomaterials can play an important role in terms of their respective mechanical properties. In this paper, a series of laboratory tests, including a compaction test, sieving test, and a CT scan test have been conducted on renewable construction waste mixtures from the Xi-Xian Highway. Using Image-Pro Plus to identify CT scan images, the quantitative indicators of aggregate particle size, contour shape, and angularity were determined, and the classification method and standard of renewable construction waste particles were determined. According to the particle contact form in the CT scan image, the construction waste particle contact can be divided into a suspension-dense structure, a skeleton-fill structure, and a skeleton-porosity structure. Furthermore, this paper analyses the destruction mode of construction waste particles and reveals the destruction mechanism of recycled construction waste mixtures. This study analyses in detail the mesoscopic characteristics of renewable construction waste mix and provides a technical reference for the broadening research and popularisation of construction waste mix. [ABSTRACT FROM AUTHOR]

Rockfill is a common irregular granular material used in most dam construction projects. The purpose of this paper is to investigate the distribution and size-dependent properties of the mechanical parameters describing the elastic properties and crushing strength of rockfill particles. These statistics can be used as a reference to calibrate the input parameters of numerical models when studying the macroscopic behavior of rockfill with particle breakage using the discrete element method. A series of limestone particles ranging in diameter from 20 to 240 mm were measured in this study using a single particle compression test. The elastic modulus, elastic contact stiffness, tensile stress and fracture force were then determined by characterizing each experimental force–displacement curve. Classical statistical methods were used. It has been shown that Weibull, lognormal and logistic functions can all represent the distributional features of the elastic modulus, tensile stress and fracture force, with the lognormal function being the optimal type here. As the grain size increases, the elastic modulus and tensile stress decrease, while the fracture force rises. Empirical models of power functions effectively reproduced these size-dependent laws. Meanwhile, the relationship between these parameters was also established. Finally, the lognormal function was adopted to express the randomness of the maximum elastic contact stiffness. Some suggestions were made after discussing the positive association between the maximum elastic contact stiffness and grain size. Moreover, the evaluation of the loading strain rates of individual particles tested shows that the present conclusions are applicable to quasi-static case. [ABSTRACT FROM AUTHOR]

Over time, natural cracks within particles propagate under tensile stress, leading to the delayed breakage of these particles, which significantly contributes to the time-dependent deformation of rockfill materials. In this study, a delayed strength model for spherical particles with virtual cracks is proposed using subcritical crack propagation theory and validated through indoor single-particle creep tests. Based on the model, particles are represented as ideal spheres in the context of triaxial compression creep simulations for rockfill, with special attention to particle size effects, discreteness, and temporal factors. The combined influence of long-term strength and maximum contact force is crucial in determining the delayed particle breakage. Comparative analysis with indoor triaxial creep tests demonstrates that the Discrete Element Method (DEM) simulations accurately model the creep deformation phenomena related to delayed particle breakage in rockfill. Furthermore, statistical analysis indicates that a minor fraction of delayed particle breakage has a negligible impact on the temporal distribution of the Normalized Maximum Contact Force (NMCF). [Display omitted] • The decay strength model of limestone particles was proposed based on the subcritical crack propagation theory. • Validation of the proposed model based on single-grain creep tests of different groups. • The mechanical properties of the creep process were statistically analyzed from the microscopic level based on DEM. [ABSTRACT FROM AUTHOR]

This paper discusses the settlement characteristics of a historical building near the corner of a supported excavation made in soft soil during the construction of a subway. Measurements from the study site at Daliang Station, Foshan, China are analysed, and the effects of partition walls are explored. The complexity of the corner effects of braced excavations is considered, and deformation forms and damage to buildings near the corners are analysed. Depression, arching, deflection, torsion, differential settlement, and inclination are studied. Finally, partition walls are proposed to reduce the impact of the corner effect on the buildings. We found that the corner effect limits the deflection and deformation of a corner building and has little effect on torsional deformation. Partition walls can significantly reduce the horizontal deformation of underground diaphragm walls and the settlement of corner buildings. The results help to understand the stress behaviour and deformation mechanism of buildings near the corners of braced excavations and on ways to control such deformation. [ABSTRACT FROM AUTHOR]

Changes in humidity can influence the mechanical performance of embankments and the bearing capacity of pavement structures. Investigating the characteristics of embankment humidity fields is important in assessing the safety and stability of highways built on embankments. This study conducted long-term monitoring of the humidity within an embankment constructed from recycled construction waste on the Xi'an-Xianyang Highway, China. Humidity field dynamics beneath the road axis, lane, soil shoulder, hard shoulder, and slope at the barricade and arc-shaped protective slope sections are analyzed in detail. The embankment humidity field distribution was uneven due to differences in the initial humidity. Areas around the road axis, sides, and top of the embankment were readily affected by rainfall. Compared with the arc-shaped protective slope section, the barricade section had good water isolation. Damaged or improper drainage components of the pavement and slope can rapidly increase the humidity in areas of water infiltration. The effect of external water infiltration on water migration within the embankment at the barricade and arc-shaped protective slope sections is investigated comprehensively. [ABSTRACT FROM AUTHOR]

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic disease characterized by the abnormal proliferation of fibroblast and excessive deposition of extracellular matrix (ECM), accompanied by inflammation and ultimately respiratory failure. Yinhuang granule (YHG), with clinical properties of clearing heat, detoxifying and anti-inflammation, is commonly used to heal upper respiratory diseases in China for decades., Purpose: To explore the improvement of YHG on bleomycin (BLM)-induced IPF in mice and its possible engaged mechanism., Methods: The mortality rate was recorded, lung function was determined and hematoxylin-eosin (H&E) staining was carried out to explore the alleviation of YHG on BLM-caused IPF in mice. Hydroxyproline, collagen I and collagen III contents were detected, and Sirius red and Masson staining were conducted to evaluate YHG's alleviation on lung fibrosis. The underlying mechanism was predicted by network pharmacology, and confirmed by Real-time polymerase chain reaction (RT-PCR), Western-blot (WB) and enzyme linked immunosorbent assay (ELISA). The binding affinity between related key proteins and active compounds in YHG was calculated by using molecular docking, and further validated by cellular thermal shift assay (CESTA)., Results: YHG (400, 800 mg/kg) weakened lung damage and pulmonary fibrosis in mice induced by BLM. Network pharmacology and experimental validation displayed that inflammation and angiogenesis participated in the YHG-provided improvement on IPF, and key involved molecules included tumor necrosis factor-α (TNFα), vascular endothelial growth factor-A (VEGFA), interleukine-6 (IL-6), etc. The data of molecular docking presented that some main active compounds from YHG had a high binding affinity with TNFR1 or VEGFR2, and some of them were further validated by CESTA., Conclusion: YHG effectively improved the BLM-induced IPF in mice via reducing inflammation and angiogenesis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

In this Letter, we demonstrate a sensitivity-enhanced strain sensor based on a shape-modulated multimode fiber (MMF). In contrast to conventional single-mode-multimode-single-mode (SMS) fiber structures, which typically contain a single cylindrical homogeneous MMF section, the shape of the MMF section in this investigation is modulated by lateral offset splicing of multiple MMF segments. Simulation results show that the designed shape-modulated MMF has a higher peak mechanical strain than that of a cylindrical MMF. Experimental results demonstrate that the strain sensitivity achieved by the shaped-modulated MMF-formed SMS fiber structure is as high as -55.63 pm/µε, which is 33 times higher than that for a cylindrical MMF-formed conventional SMS fiber structure at -1.65 pm/µε. This high sensitivity and low-fabrication cost SMS fiber sensor has the potential to be a promising candidate in precise strain measurement applications.

Hepatic sinusoidal obstruction syndrome (HSOS) is a death-dealing liver disease with a fatality rate of up to 67%. In the study present, we explored the efficacy of andrographolide (Andro), a diterpene lactone from Andrographis Herba, in ameliorating the monocrotaline (MCT)-induced HSOS and the underlying mechanism. The alleviation of Andro on MCT-induced rats HSOS was proved by biochemical index detection, electron microscope observation, and liver histological evaluation. Detection of hepatic ATP content, mitochondrial DNA (mtDNA) copy number, and protein expression of nuclear respiratory factor-1 (NRF1) and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PPARGC1A) demonstrated that Andro strengthened mitochondrial biogenesis in livers from MCT-treated rats. Chromatin immunoprecipitation assay exhibited that Andro enhanced the occupation of nuclear factor erythroid 2-related factor 2 (NFE2L2, also known as NRF2) in the promoter regions of both PPARGC1A and NRF1. Andro also activated the NRF2-dependent anti-oxidative response and alleviated liver oxidative injury. In Nrf2 knock-out mice, MCT induced more severe liver damage, and Andro showed no alleviation in it. Furthermore, the Andro-activated mitochondrial biogenesis and anti-oxidative response were reduced in Nrf2 knock-out mice. Contrastingly, knocking out Kelch-like ECH-associated protein 1 (Keap1), a NRF2 repressor, reduced MCT-induced liver damage. Results from co-immunoprecipitation, molecular docking analysis, biotin-Andro pull-down, cellular thermal shift assay, and surface plasmon resonance assay showed that Andro hindered the NRF2-KEAP1 interaction via directly binding to KEAP1. In conclusion, our results revealed that NRF2-dependent liver mitochondrial biogenesis and anti-oxidative response were essential for the Andro-provided alleviation of the MCT-induced HSOS. Graphical Headlights: 1. Andro alleviated MCT-induced HSOS via activating antioxidative response and promoting mitochondrial biogenesis. 2. Andro-activated antioxidative response and mitochondrial biogenesis were NRF2-dependent. 3. Andro activated NRF2 via binding to KEAP1., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Utilizing regenerated polyester fibers (RPFs) for the reinforcement of silty road bases not only enhances the soil's engineering performance but also offers a sustainable method for repurposing waste polyester bottles. To investigate the engineering properties and microscopic behaviors of this reinforced silty soil, a series of extensive physico-mechanical tests were conducted, supplemented by Scanning Electron Microscopy (SEM) analyses. These evaluations focused on the influence of variables such as fiber content, fiber length, moisture content, and curing duration on the modified soil's performance. The fiber content of the test was 0-1%, and the fiber length was 6-17 mm. The results indicate that curing age had a less significant impact on liquid and plastic limits than the addition of fiber, along with a marginal decline in the plasticity index over time. The rate of shrinkage in the unmodified soil was between 1.04 and 1.45 times higher than that in the fiber-reinforced soil, indicating effective shrinkage control by the fibers. However, variations in maximum dry density ( ρ dmax ) were insignificant across different fiber contents, while a slight increase was observed in the optimum moisture content (OMC) as fiber dosage increased. After a 28-day curing period, the resilient modulus and California Bearing Ratio (CBR) met highway road base design standards. A decline in unconfined compressive strength was noted when the fiber dosage exceeded 0.2%. The addition of fibers mitigated diagonal cracking and shifted the failure pattern towards a more ductile mode. This research contributes scientific insights for the broader application and promotion of silty road base improvement techniques using RPFs.