Search Results (194)

The disc-buckle scaffold system demonstrates significant advantages in prefabricated construction applications, particularly in terms of installation efficiency, load-bearing capacity, and standardization. Guangzhou Construction Group Co., Ltd., a leading enterprise in promoting prefabricated building development in Guangdong Province, China, has collaborated with the Guangdong University of Technology to develop an innovative disc-buckle scaffold system. The main difference between different scaffolds lies in the connection part of the joint. The mechanical behavior of scaffold joint plays a critical role in determining the structural integrity of the entire scaffolding system. So, the novel disc-buckle scaffold proposed in this paper is mainly new in the joint. Finite element simulation based on the test results is employed to study the performance of the novel scaffold joint in this paper. The results show that the newly developed scaffold joint exhibits superior mechanical performance, characterized by a bending stiffness of 34.5 kN·m/rad. The joint demonstrates maximum tensile and compressive bearing capacities of approximately 108 kN and 70 kN in the transverse direction, respectively. Furthermore, the joint’s maximum shear bearing capacity exceeds 180 kN, surpassing the buckling critical force of the vertical steel pipe and satisfying all strength requirements. The scaffold joint exhibits robust hysteresis characteristics, and the wedge-shaped connection mechanism maintains consistent stiffness and load-bearing symmetry under both positive and negative bending moments. The proposed disc-buckle steel scaffold joint features a minimal number of components, achieving an optimal balance between structural performance and economic efficiency. Full article

The present study systematically investigated the cesium (Cs) enrichment characteristics and physiological responses to Cs exposure in radish (Raphanus sativus L.) seedlings under hydroponic conditions through integrated physiological, biochemical, and transcriptome analyses. The results showed that the Cs content in radish roots, stems, and cotyledons increased progressively with rising Cs concentrations (0.25–2 mM), and Cs mainly accumulated in the cotyledon. The transfer factor (TF) increased by 63.29% (TF = 3.87) as the Cs concentration increased from 0.25 to 2 mM, while the biological concentration factor (BCF) decreased by 72.56% (BCF = 14.87). Severe growth inhibition was observed at 2 mM Cs stress, with biomass reduction reaching 29.73%. The carotenoid content decreased by 11.92%; however, the total chlorophyll content did not change significantly, and the photosynthesis of radish was not affected. In addition, Cs exposure disrupted mineral nutrient homeostasis, decreasing potassium (K), sodium (Na), magnesium (Mg), and iron (Fe) content. The superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities, reactive oxygen species (ROS), and malondialdehyde (MDA) content increased under the different Cs treatments, which indicated that Cs exposure induced oxidative stress response in radish seedlings. Transcriptome analysis detected a total of 4326 differentially expressed genes (DEGs), in which altered expression patterns in genes associated with mineral transport, antioxidant systems, and carotenoid biosynthesis pathways in radish under 2 mM Cs treatment were observed. In conclusion, this study comprehensively investigated the physiological and molecular responses of radish to Cs stress, revealing that Cs accumulation exhibited site-specific preference and concentration dependence and induced physiological disturbances, including growth inhibition and photosynthetic pigment metabolism alterations. At the transcription level, Cs activated the enzymatic antioxidant system, related genes, and stress-response pathways. Notably, this study is the first to demonstrate that Cs disrupts plant mineral nutrition homeostasis and inhibits carotenoid biosynthesis. These findings establish a crucial theoretical foundation for utilizing radish in Cs-contaminated phytoremediation strategies. Full article

Escherichia coli contamination in poultry is a significant concern due to its potential to cause foodborne illness. The presence of extraintestinal pathogenic E. coli (ExPEC) strains in chicken carcasses can lead to severe human infections. This study investigates the prevalence, virulence, and antibiotic resistance of E. coli isolates from chicken carcasses processed in both wet market and industrial environments, with a focus on the detection capabilities of MALDI-TOF MS. A total of 119 E. coli isolates were obtained. Only a small proportion (5/119) carried enteropathogenic virulence genes. In contrast, 71.42% (85/119) of the isolates harbored multiple extraintestinal virulence genes. Among these, iucC and sitA, which are associated with systemic infections, were present in 68.24% (58/85) and 43.53% (37/85) of the isolates, respectively. Furthermore, 47.06% (56/119) of the isolates carrying at least two extraintestinal virulence genes were classified as ExPEC. Additionally, 94.6% (54/56) of ExPEC isolates were multidrug resistant (MDR), showing resistance to over three antibiotic classes, raising concerns about the spread of antibiotic resistance. MALDI-TOF MS profiling revealed significant heterogeneity among the ExPEC isolates, with no distinct clustering patterns based on processing environment or sampling site. These findings underscore the public health risks posed by ExPEC in poultry and emphasize the need for improved surveillance, stringent hygiene practices, and responsible antibiotic use in poultry production. Full article

In this study, we systematically investigated the mechanisms of the antioxidation and anti-lipid accumulation effects of antioxidant peptides from Litsea cubeba on a free fatty acid (FFA)-induced NAFLD model of HepG2 cells. The NAFLD cell model was constructed by inducing the HepG2 hepatocellular carcinoma cell line with 0.5 mmol/L FFAs, and AQRDAGLL, QEGPFVR, and DVPPPRGPL were given to the culture to study their lipid-lowering and antioxidant activities on NAFLD cells. The lipid-lowering activities of the three antioxidant peptides were evaluated by Oil Red O staining and TG and TC content assays, and the results showed that all three peptides had strong ameliorating effects on FFA-induced lipid accumulation in NAFLD cells. The intracellular antioxidant protease (CAT, GSH, and SOD) activity levels and lipid peroxidation (MDA) content were measured and intracellular ROS levels were detected. The results showed that after intervention with the antioxidant peptides, the intracellular ROS levels in the NAFLD model cells were significantly reduced, the SOD and CAT activities were increased, the GSH content was elevated, and the MDA content was reduced, which indicated that AQRDAGLL, QEGPFVR, and DVPPPRGPL were able to inhibit the oxidative stress of the cells effectively and to achieve the effect of intervening in NAFLD. JC-1 fluorescence staining experiments showed that the mitochondrial membrane potential function of NAFLD cells was restored under the effect of the antioxidant peptides. Molecular dynamics simulations revealed that the main driving force between QEGPFVR and Keap1 protein was van der Waals forces, ΔG = −62.11 kcal/mol, which indicated that QEGPFVR was capable of spontaneously binding to Keap1 protein. Full article

Porcine epidemic diarrhea virus (PEDV), the etiology of porcine epidemic diarrhea (PED), continues to impose severe economic burdens on pig farms in China. The continuous emergence of new variant strains makes it difficult for vaccinated sows to provide protective immunity to piglets. Hence, there is an urgent need for efficacious therapeutic drugs in clinical practice. In the present study, the antiviral activity of GS-441524, a nucleoside analogue, against PEDV was evaluated. It can efficiently inhibit the proliferation of trypsin-dependent and trypsin-independent PEDVs in a dose-dependent manner, exhibiting greater efficacy against the trypsin-independent strain. GS-441524 can inhibit trypsin-independent PEDV proliferation in Vero cells with EC₅₀ and CC₅₀ values of 2.6 μM and 104.4 μM, respectively. As expected, GS-441524 exerts its inhibitory effect during the replication phase of the four stages of the PEDV proliferation cycle. Even at a high viral infection dose of MOI 0.5 or added 6 h post-viral infection, 20 μM GS-441524 can still effectively inhibit PEDV proliferation. These findings emphasize the potent antiviral activity of GS-441524 against PEDV, and its therapeutic efficacy on PEDV-infected piglets warrants further investigation. Full article

ACS (1-aminocyclopropane-1-carboxylic acid synthase) is a member of the aminotransferase superfamily and a pyridoxal phosphate-dependent enzyme. ACS is also a rate-limiting enzyme for the biosynthesis of ethylene and has been linked with plant development, growth, and stress responses. However, information on ACS genes in the soybean genome is limited. In this study, we identified ACS genes in soybean through phylogenetic trees and conserved motifs and analyzed their cis-acting elements, subcellular localization, and expression patterns. Twenty-two members of the ACS family were identified in soybean, and they were divided into four subfamilies based on phylogenetic relationships. Moreover, the results of Arabidopsis mesophyll protoplasts showed that GmACS1, GmACS8, and GmACS15 were all localized in the nucleus and cell membrane. Cis-regulatory elements and qRT-PCR analyses indicated markedly increased levels of GmACS transcripts under hormone treatments and abiotic stress conditions (drought, alkalinity, and salt). In addition, under different abiotic stresses, the potential functional variations across the GmACS isoforms were mirrored in their differential expression. The analysis of transcriptional response to salinity indicated that salt stress might primarily be mediated by the GmACS15 gene. GmACS15 was also found to reduce salt-induced oxidative damage by modulating the ROS-scavenging system, cellular redox homeostasis, and maintaining intracellular Na⁺/K⁺ balance. The results of this investigation revealed the involvement of the ACS gene family in soybean stress-response pathways, including the identification of a potential target for enhancing salt tolerance in soybean. Full article

Fourier-transform imaging spectroscopy (FTIS) faces inherent limitations in spectral resolution due to the maximum optical path difference (OPD) achievable by its interferometer. To overcome this constraint, we propose a novel spectral super-resolution technology integrating a Fabry–Pérot interferometer (FPI) with FTIS, termed multi-component joint interferometric hyperspectral imaging (MJI-HI). This method leverages the FPI to periodically modulate the target spectrum, enabling FTIS to capture a modulated interferogram. By encoding high-frequency spectral interference information into low-frequency interference regions through FPI modulation, an advanced inversion algorithm is developed to reconstruct the encoded high-frequency components, thereby achieving spectral super-resolution. This study analyzes the impact of primary optical errors and tolerance thresholds in the FPI and FTIS on the interferograms and spectral fidelity of MJI-HI, along with proposing algorithmic improvements. Notably, certain errors in the FTIS and FPI exhibit mutual interference. The theoretical framework for error analysis is validated and discussed through numerical simulations, providing critical theoretical support for subsequent instrument development and laying a foundation for advancing novel spectral super-resolution technologies. Full article

Cloud optical thickness (COT) stands as a critical parameter governing the radiative properties of clouds. This study develops a convolutional neural network (CNN) model to retrieve the COT of single-layer non-precipitating clouds during nighttime using FY-4B satellite data. The model integrates multi-channel brightness, temperature, and geographic and temporal features, without relying on auxiliary meteorological data, using the multi-point averaged 532 nm COT from CALIPSO as ground truth for training. Performance evaluation demonstrates robust retrieval accuracy, achieving coefficients of determination (R²) of 0.88 and 0.73 for satellite zenith angles (SAZAs) < 70° and >70°, respectively. Key advancements include the incorporation of temporal features, the Squeeze-and-Excitation (SE) module, and a multi-point averaging technique, each validated through ablation experiments to reduce bias and enhance stability. Meanwhile, a model error analysis experiment was conducted that further clarified the performance boundaries of the model. These findings underscore the model’s capability to retrieve the COT of single-layer non-precipitating clouds during nighttime with high precision. Full article

Thoracic aortic aneurysm (TAA) is a life-threatening peripheral vascular disease with a complex pathogenesis. Altered mitochondrial function in vascular smooth muscle cells has been implicated in TAA development. However, the link between mitochondrial functional status and immune cell behavior in TAA patients remains largely unexplored. In this study, we analyzed several bulk RNA-seq and snRNA-seq datasets of TAA from the NCBI-GEO and Genome Sequence Archive database, identifying differentially expressed mitochondrial-related genes (DE-MRGs). To assess mitochondrial function, we calculated a mitoscore to represent the overall expression level of MRGs. Our analysis revealed mitochondrial-mediated apoptosis occurring in M1 macrophages, while CD4 + T cells demonstrated the activation of quality control mechanisms, such as mitochondrial fission. Through LASSO regression and SVM-RFE, we identified key MRGs, including MUCB, ARRB2, FRG, and ALPL, which we further validated using TAA mouse models. Additionally, we found that DE-MRGs were closely linked to methionine metabolism. In conclusion, this study highlights mitochondrial dysfunction in immune cells associated with TAA, shedding light on potential mitochondrial roles in TAA pathogenesis. Full article

A new spectral super-resolution technique was proposed by combining the Fabry–Perot interferometer (FPI) with Temporally and Spatially Modulated Fourier Transform Imaging Spectrometer (TSMFTIS). This study uses the multi-beam interference of the FPI to modulate the target spectrum periodically, and it acquires the modulated interferogram through TSMFTIS. The combined interference of the two techniques overcomes the limitations of the maximum optical path difference (OPD) on spectral resolution. FPI is used to encode high-frequency interference information into low-frequency interference information, proposing an inversion algorithm to recover high-frequency information, studying the impact of FPI optical defects on the system, and proposing targeted improvement algorithms. The simulation results indicate that this method can achieve multi-component joint interference imaging, improving spectral resolution by twofold. This technology offers advantages such as high throughput, stability, simple and compact structure, straightforward principles, high robustness, and low cost. It provides new insights into TSMFTIS spectral super-resolution research. Full article

This paper presents a space-based limb-imaging spectrometer (LIS) for detecting atmospheric O₂ airglow; it scans the atmosphere with a vertical range of 10–100 km and has a vertical resolution of 2 km. The LIS’s detection performance needs to be examined before launch. A forward radiative transfer model (RTM) of airglow is studied to determine the airglow emission intensity. Spectral and radiation calibration is conducted to obtain the response parameters. Based on the airglow emission intensity, calibration results, and airglow spectral lines, the LIS’s simulated spectra are obtained, and then an optimal estimation inversion method for the LIS is studied. The results show that the LIS’s spectral range is 498.1 nm–802.3 nm, with a spectral resolution of 1.38 nm. Simulation results show that the LIS can detect airglow emission spectral lines, which characterize their dependence on temperature. The digital number response value is 20% to 50% of the saturation value. An inversion error analysis shows that, when the signal-to-noise ratio (SNR) of the LIS is 1000 and the prior temperature error is 10%, the inversion errors are 6.2 and 3 K at 63 and 77 km, respectively. This study shows that the LIS can achieve good SNR detection for airglow. Full article

This paper focuses on the transverse tensile and compressive mechanical properties of T800-grade unidirectional (UD) carbon fiber-reinforced polymers (CFRPs). Firstly, transverse tensile and compressive tests were conducted on UD composite laminates, yielding corresponding stress–strain curves. The results indicated that, for tension, the transverse tensile modulus, strength, and failure strain were 8.7 GPa, 64 MPa, and 0.74%, respectively, whereas for compression, these values were 8.4 GPa, 197.1 MPa, and 3.43%, respectively. The experimental curves indicated brittle failure under tensile loadings and significant plastic failure characteristics under compressive loading for the T800-grade composite. Subsequently, fractography experiments were performed to observe the fracture morphologies, revealing that tensile fractures were through-thickness cracks perpendicular to the loading direction, while compressive fractures were at a 52° angle to the loading direction. Finally, a micromechanical finite element method (FEM) was employed to simulate the tensile and compressive failure processes of the unidirectional composite, and the tensile and compressive properties were predicted. The simulation results showed that under both tensile and compressive loadings, interfacial elements failed first, causing stress concentration and damage to nearby resin elements. The damaged resin and interfacial elements expanded and connected, leading to ultimate failure. The predicted tensile stress–strain curve exhibited linear characteristics consistent with the experimental results in most regions but showed more pronounced nonlinearity before ultimate failure. The predicted compressive stress–strain curve aligned well with the experimental results in terms of nonlinearity. The predicted elastic modulus, failure strengths, and failure strains were in good agreement with the experimental results, with differences of 1.1% (tension modulus), 3.2% (tension strength), and 13.5% (tension failure strain), and 3.6% (compression modulus), −8.5% (compression strength), and −3.8% (compression failure strain). The final failure morphologies were in good accordance with the fractography experimental observations. Full article

Grid-forming converters (GFMCs) have emerged as enablers in modern power systems. However, they face the transient stability problem, which hinders them from successful fault ride-through (FRT) and potentially results in the system’s collapse. These problems have drawn increasing attention, leading to a rise in related research. To capture the advancements in the field, this paper reviews studies on the transient stability analysis and enhancement of GFMCs. In particular, the transient stabilities of GFMCs with first- and second-order power control modes are reviewed, and a comprehensive comparison of the two modes is provided. Additionally, this paper classifies the transient stability enhancement methods of GFMCs into six types: active power, reactive power, voltage amplitude, virtual impedance, inertia and damping regulations. Moreover, this paper summarizes the effects and limitations of each method from the perspective of practical application. Based on the analysis, this paper further discusses future research directions for the transient stability of GFMCs. Full article

Timely sowing is a crucial cultivation practice for enhancing crop productivity. In Shandong Province, inadequate supporting cultivation techniques are the primary factors limiting the yield and quality improvement of high-quality strong-gluten wheat (Triticum aestivum L.). A promising strategy for achieving synergistic improvements in both yield and quality involves matching the sowing date and density to the specific ecological conditions of each region. To explore this approach, we conducted continuous field experiments at three testing stations—Jining, Dezhou, and Yantai—across the major wheat-growing regions of Shandong Province from 2019 to 2021. Four sowing dates (T1: October 5; T2: October 15; T3: October 25; and T4: November 5) and seven planting densities (ranging from 135 × 10⁴ plants ha⁻¹ to 405 × 10⁴ plants ha⁻¹, denoted as D1–D7) were tested at each location. The results revealed that the wheat yield in each ecological zone initially increased, then decreased as the sowing dates were delayed. In Jining and Dezhou, high grain yields were typically observed at all densities under T3, while Yantai showed optimal yields under T2. Specifically, Jining achieved the highest grain yield of 9326.6 kg ha⁻¹ with 315 × 10⁴ plants ha⁻¹ on October 25 (T3D5), while Dezhou and Yantai reached their maximum yields under 225 × 10⁴ plants ha⁻¹ on October 15 (T2D3), with yields of 8784.0 kg ha⁻¹ and 9366.3 kg ha⁻¹, respectively. Except in Dezhou, the wheat quality compliance rate at all sites followed an increasing trend initially, which then declined with later sowing dates. In Jining and Yantai, high-quality compliance rates were most frequently achieved under T2, while Dezhou showed optimal quality rates under T1. In conclusion, selecting appropriate sowing dates and densities can lead to synergistic improvements in both grain yield and quality of strong-gluten wheat across Shandong’s wheat-growing regions. Full article

Salt stress is an environmental factor that limits plant seed germination, growth, and survival. We performed a comparative RNA sequencing transcriptome analysis during germination of the seeds from two cultivars with contrasting salt tolerance responses. A transcriptomic comparison between salt-tolerant cotton cv Jin-mian 25 and salt-sensitive cotton cv Su-mian 3 revealed both similar and differential expression patterns between the two genotypes during salt stress. The expression of genes related to aquaporins, kinases, reactive oxygen species (ROS) scavenging, trehalose biosynthesis, and phytohormone biosynthesis and signaling that include ethylene (ET), gibberellin (GA), abscisic acid (ABA), jasmonic acid (JA), and brassinosteroid (BR) were systematically investigated between the cultivars. Despite the involvement of these genes in cotton’s response to salt stress in positive or negative ways, their expression levels were mostly similar in both genotypes. Interestingly, a PXC2 gene (Ghir_D08G025150) was identified, which encodes a leucine-rich repeat receptor-like protein kinase (LRR-RLK). This gene showed an induced expression pattern after salt stress treatment in salt-tolerant cv Jin-mian 25 but not salt-sensitive cv Su-mian 3. Our multifaceted transcriptome approach illustrated a differential response to salt stress between salt-tolerant and salt-sensitive cotton. Full article