Search Results (51)

Extrachromosomal circular DNA (eccDNA) has been recognized as a key player in tumorigenesis and progression. However, eccDNA transcriptional regulatory mechanisms under DNA damage in cancer remain poorly characterized. Here, we used doxorubicin to induce DNA damage in the hepatocellular carcinoma cell line HepG2 and performed Circle-seq to profile eccDNAs before and after the damage. We observed a significant increase in the number, length, and chromosomal distribution density of eccDNAs following DNA damage. RNA-seq revealed that the expression of genes carried on eccDNA was positively correlated with eccDNA copy number under DNA damage. Further ATAC-seq profiling identified distinct chromatin characteristics at eccDNA breakpoint regions compared to other regions of eccDNA and linear genomic regions. Additionally, eccDNAs generated under DNA damage preferentially originated from linear genomic regions characterized by low GC content and hypomethylation. Finally, by integrating Hi-C and H3K27ac ChIP-seq, we uncovered that eccDNAs with mobile enhancer activity (ME-eccDNAs) display significantly enhanced chromatin interactions and H3K27ac enrichment after DNA damage. Overall, our findings systematically elucidate the DNA damage-driven mechanisms underlying eccDNA biogenesis, chromatin characteristics and transcriptional regulation in HCC HepG2 cells. Full article

Accurate water hammer calculations are crucial for hydraulic safety and unit stability in hydropower systems with free-surface tailrace tunnels. However, existing models often neglect hydraulic variations in free-surface sections, while the commonly used method of characteristics tends to cause numerical instability and dissipation due to interpolation or wave speed adjustments, leading to significant computational errors. Aiming at the transient process of hydropower stations with free-surface tailrace tunnels and fully considering the influence between pressure and free-surface conditions, this study employs the second-order Godunov scheme to solve the governing flow equations for pressurized and free-surface flows. A generalized boundary of the regulating pool and a variable time step calculation method were proposed to solve the problem of real-time coupling calculation in the pressure–free-surface transition area. The results show that during the large fluctuation transient process, the hydraulic characteristics of the free-surface flow have little impact on the inlet pressure of the unit’s volute and the unit’s rotational speed but have a significant impact on the fluctuation period and extreme value of the inlet pressure of the draft tube. During the small fluctuation transient process, the hydraulic characteristics of open channel flow are beneficial for improving the unit’s regulation quality. This indicates that considering the hydraulic characteristics of free-surface flow is of great significance for realizing an accurate simulation of the transient process of hydropower stations. Full article

Quadrupole mass spectrometers are highly sensitive and specific analytical instruments, widely used in pharmaceuticals, clinical diagnostics, and other fields. Their performance depends on a tuning process to optimize key parameters, which has traditionally relied on engineers’ expertise or simple univariate search methods. This paper proposes an automatic tuning method using an improved differential evolution algorithm. This algorithm introduces a ranking and subpopulation classification for individuals, enabling distinct mutation strategies. Validation on the CEC-2017 benchmark functions confirms the superiority of the improved algorithm. In automatic tuning experiments, it achieved a 25.3% performance gain over the univariate search method and also surpassed both the classical differential evolution algorithm and standard particle swarm optimization algorithm. This method proves to be an effective approach for enhancing the performance of quadrupole mass spectrometers. Full article

Whole-plant corn silage is a critical feedstuff in global ruminant production, and its nutrient composition is closely tied to harvest timing. As starch acts as the primary energy source in silage-based diets, investigating changes in starch degradation rate provides a theoretical basis for optimizing the efficient utilization of whole-plant corn and its silage in ruminant production. In this study, whole-plant corn (harvested from the milk stage to full ripening stage) and its corresponding silage were used as experimental materials. An in vitro simulated rumen fermentation system was employed to determine the contents of starch, prolamin, amylose, and amylopectin in the samples. The results showed that with delayed harvest time, starch content in both whole-plant corn and its silage increased significantly; prolamin and amylose contents first decreased, then increased; amylopectin content first rose significantly before decreasing; and both starch disappearance rate and speed exhibited a trend of first increasing, then decreasing. After silage fermentation, the silage had significant increases in starch, amylose, and amylopectin contents, and starch disappearance rate; prolamin content decreased; and starch disappearance speed increased extremely significantly. This study indicates that whole-plant corn harvest time and silage fermentation regulate the ruminal starch degradation pattern by altering starch structure, prolamin content, and the proportion of rapidly degradable starch. Full article

This study systematically investigated the decolorization efficacy and detoxification effect of crude laccase derived from Pleurotus ostreatus yang1 on azo and triphenylmethane dyes. This research encompassed decolorization efficiencies for 15 dyes (7 azo dyes and 8 triphenylmethane dyes), time course decolorization kinetics, and detoxification assessment using rice (Oryza sativa) and wheat (Triticum aestivum) seed germination as phytotoxicity indicators for both single-dye and mixed-dye systems. Molecular docking was employed to elucidate the laccase–dye interaction mechanisms. The results demonstrated that crude laccase from Pleurotus ostreatus yang1 exhibited significant decolorization efficiency and effective detoxification capacity toward both azo dyes and triphenylmethane dyes. It also displayed considerable decolorization efficiency for mixtures of azo and triphenylmethane dyes (mixture of two types of dyes), along with strong detoxification capability against the phytotoxicity of mixed dyes. Crude laccase showed robust continuous batch decolorization capability for azo dyes Alpha-naphthol Orange (α-NO) and Mordant Blue 13 (MB13). Similarly, it achieved high continuous batch decolorization efficiency for triphenylmethane dyes (e.g., Cresol Red, Acid Green 50) while maintaining stable laccase activity throughout the decolorization process. Crude laccase demonstrated excellent reusability and sustainable degradation performance during the continuous batch decolorization. The decolorization of crude laccase could significantly reduce or completely eliminate the phytotoxicity of both single dyes and mixtures of two dyes (pairwise mixtures of different types of dyes, totaling 18 different combinations). The results of molecular docking between the laccase protein and structurally diverse dyes further elucidated the underlying causes and potential mechanisms for variations in the catalytic ability of laccase toward different structural dyes. In summary, crude laccase from Pleurotus ostreatus yang1 possessed great application value and potential for efficiently degrading and detoxifying dye pollutants of different structural types. Full article

The rheological behavior of clay in a water–salt environment determines the long-term deformation and structural stability of building materials and geotechnical engineering. In this study, the effects of salinity on the rheological behavior and microstructure stability of the clay mineral illite were investigated through steady-state and dynamic rheological tests. The results reveal that specimens with different salinities exhibit shear thinning behavior during the steady-state rheological test. When the shear rate is higher than 0.5 s⁻¹, the flow curves are described well by the Herschel–Bulkley model. As the salinity increases from 0 to 1.8 mol/L, the yield stress varies from 1500 to 3500 Pa. With the increase in salinity, the consistency factor of the specimens increases, while the flow coefficient decreases. Under dynamic loading, high-salinity specimens exhibit higher modulus and yield stresses, thereby enhancing the stability of the microstructure. The viscoelastic–plastic constitutive model under dynamic loading has been established, which can effectively describe and calculate the long-term deformation of clay minerals. These research results provide reference and guidance for understanding the rheological behavior of clay. Full article

Focusing on the problem that it is difficult to maintain a high diagnostic accuracy rate, short running time, and robust generalization capability in the face of a strong-noise environment in rolling bearing fault diagnosis, a bearing fault diagnosis model (GMNR-CABA-MAGRU) founded upon a new attention-mechanism-improved residual network (ResNet-CABA) and a Gram denoising module (GMNR) is proposed, and the CWRU bearing dataset is used for verification. Under the 0-load condition in a noise-free environment, the diagnostic accuracy of this model reached 99.66%, and the running time was only 52.74 s. Then, a bearing dataset with added Gaussian noise from −4 db to 4 db was verified, and this model was still able to maintain a diagnostic accuracy of 90.32% under the strong-noise environment of −4 db SNR. And migration experiments were carried out under different load conditions, and this model was also able to maintain a very high accuracy rate. Moreover, in all the above experiments, this model performed better than various comparative models. The developed framework demonstrated superior diagnostic precision, enhanced robustness, and improved generalization capability. Full article

Currently, in the domain of surface defect detection on hot-rolled strip steel, detecting small-target defects under complex background conditions and effectively balancing computational efficiency with detection accuracy presents a significant challenge. This study proposes CTL-YOLO based on YOLO11, aimed at efficiently and accurately detecting blemishes on the surface of hot-rolled strip steel in industrial applications. Firstly, the CGRCCFPN feature integration network is proposed to achieve multi-scale global feature fusion while preserving detailed information. Secondly, the TVADH Detection Head is proposed to identify defects under complex textured backgrounds. Finally, the LAMP algorithm is used to further compress the network. The proposed algorithm demonstrates excellent performance on the public dataset NEU-DET, achieving a mAP50 of 77.6%, representing a 3.2 percentage point enhancement compared to the baseline algorithm. The GFLOPs is reduced to 2.0, a 68.3% decrease compared to the baseline, and the Params are reduced to 0.40, showing an 84.5% reduction. Additionally, it exhibits strong generalization capabilities on the public dataset GC10-DET. The algorithm can effectively improve detection accuracy while maintaining a lightweight design. Full article

Based on considering the stress state distribution and potential failure surface of the specimen during uniaxial compression, the drilling parameters (layout, spacing, position) are set. Thoroughly understanding the influence of different drilling parameters on the pressure relief effect is conducive to reducing the occurrence of coal mine rock burst accidents. Through laboratory tests and numerical simulation tests under different drilling parameters, the influence laws of mechanical parameters, failure characteristics, AE characteristic parameters and energy evolution of specimens under different drilling parameters were studied. The pressure relief effect under different drilling parameters was evaluated by using the pressure relief effect evaluation index (X), and the best combination of drilling parameters was obtained. The results show the following: (1) Compared with the intact specimen, the peak strength of the drilling specimen is significantly reduced, and the drilling layout has the greatest influence on the mechanical properties, followed by the drilling spacing and drilling position. (2) Different drilling layouts will form different weak-strength surfaces in the specimen, and lead the expansion and penetration of cracks, resulting in different failure modes of the specimen. The stress distribution inside the specimen will affect the stress concentration around the borehole, finally affect the damage degree of the specimen. (3) Drilling can not only effectively reduce the energy accumulation capacity, but also enhance the degree of energy dissipation. The AE ringing counts and energy of the triangular-drilling specimens are the least. The AE ringing counts and energy decrease first and then increase with the increase in drilling spacing, and are the smallest at three times the drilling diameter. The AE ringing counts and energy increase gradually with the upward movement of the drilling position. (4) The optimal combination of drilling parameters was obtained by the test, and it was triangular-layout drilling, drilling spacing three times the diameter, and the drilling position in the middle of the specimen, and the value of the pressure relief effect evaluation index (X) was 65.41. The research results can provide some reference for the selection and optimization of drilling pressure relief parameters in rock burst mines. Full article

Uncovering the intricate relationships within the realm of ecosystem services (ESs) across various spatial and temporal dimensions, as well as their nonlinear relationships with natural–social factors, is a fundamental condition for regional ecosystem management. This study focuses on Honghe Prefecture, Yunnan Province, and it quantifies the supply of ESs at the grid and township scales, clarifies the interrelationships among ESs and influencing elements, and proposes cross-scale regional ecological management strategies. The findings indicate the following: (1) ESs exhibited spatial variability. In the last 20 years, the supply capacity of food production (FP) increased by about 46%, while other ESs showed a downward trend. (2) Synergistic effects among ESs primarily occurred between WY, habitat quality (HQ), carbon sequestration (CS), and soil conservation (SC), while trade-off effects mainly took place between FP and other ESs. (3) Significant and dramatic changes in the ecosystem service bundles were observed in the southern mountainous areas. At the grid scale, the overall area of the integrated ecological bundle declined by approximately 88%. However, the proportion of the HQ-CS key synergy bundle increased from 15.68% to 40.60%. Similar spatial patterns and trends were also observed at the township scale. (4) There was a notable reduction in the comprehensive supply of the ecosystem service index (ESI) in the southwest, in which human activities and climate drought factors played a major negative driving role, and some driving factors had threshold effects with the ESI. Existing research often ignores the nonlinear relationship between complex spatiotemporal dynamics and ecosystem services. Thus, this study constructed a comprehensive cognitive framework for regional ES status from the perspective of “supply–interaction–driving–threshold” for ESs, providing a more comprehensive understanding of regional ES management. Full article

Girdling is a crucial technique for promoting the close-to-nature transformation of plantation forests in Hainan Tropical Rainforest National Park (HNNP). It has shown effectiveness in aspects such as community structure and biodiversity restoration. However, its impacts on ecological functions like eco-hydrology still require further in-depth investigation. This study analyzes the impact of girdling on the eco-hydrological indices of three plantations—Acacia mangium, Pinus caribaea, and Cunninghamia lanceolata—through field investigations and laboratory tests. The data was evaluated using a game theory combination weighting-cloud model. The results show that the eco-hydrological indicators of leaf litter in A. mangium increased by 5.77% while those of P. caribaea and C. lanceolata decreased by 11.86% and 5.29%, respectively. Soil bulk density decreased slightly across all plantations while total porosity increased, with A. mangium showing the highest increase of 20.31%. Organic carbon content increased by 76.81% in A. mangium and 7.24% in C. lanceolata, whereas it decreased in P. caribaea. Saturated hydraulic conductivity increased by 33.32% in P. caribaea and 20.91% in A. mangium but decreased in C. lanceolata. Based on the cloud model, the eco-hydrological function of A. mangium improved from ‘medium’ to ‘good’, while that of P. caribaea and C. lanceolata declined towards the ‘poor’ level. In summary, during the process of close-to-nature transformation of tropical rainforests, girdling is an effective method to enhance the ecohydrological functions of broadleaf planted forests. However, for coniferous species, the ecohydrological functions of the planted forests weaken in the short term following the transformation. Full article

The pursuit of highly effective, low-toxicity, and eco-friendly algicides for controlling and eradicating harmful algal blooms (HABs) is of paramount importance. The natural allelochemical bacillamide A has displayed impressive algicidal activity against harmful algae with favorable safety profiles. However, the poor synthetic efficiency and large dose requirements of bacillamide A limit its further application. In this paper, 17 thiazole-containing bacillamide derivatives (BDs) were designed and synthesized in three linear steps as potential algicides. Eight compounds (6a, 6c, 6j, 7b, 7c, 7d, 7e, and 7g) displayed potent inhibitory effects against Prorocentrum minimum, Skeletonema costatum, and Alexandrium pacificum, and they had similar or better activity than the positive control (CuSO₄) and bacillamide A. Compound 6a exhibited the most potent algicidal activity against S. costatum (half-maximal effective concentration [EC₅₀] = 0.11 μg/mL), being 23-fold more potent than bacillamide A, 28-fold more potent than CuSO₄, and 39-fold more potent than Diuron. Compound 6j exhibited significant algicidal activity against the toxic dinoflagellates P. minimum (EC₅₀ = 1.0 μg/mL) and A. pacificum (EC₅₀ = 0.47 μg/mL), being 3–5-fold more potent than natural bacillamide A, Diuron, and CuSO₄. Micrographs and SEM images revealed that 6j induced cell wall rupture and cellular content leakage. Biochemical and physiological studies indicated that 6j might partially disrupt the antioxidant and photosynthetic systems in algal cells, resulting in morphological changes, cell wall rupture, and inclusion leakage. Our work suggests that 6j has a distinct mode of action from CuSO₄ and provides a promising candidate for the development of new algicides, worthy of further investigation. Full article

Beneficial fungi of the genus Trichoderma are among the most widespread biocontrol agents that induce a plant’s defense response against pathogens. Fusarium solani is one of the main pathogens that can negatively affect Astragalus mongholicus production and quality. To investigate the impact of Trichoderma harzianum on Astragalus mongholicus defense responses to Fusarium solani, A. mongholicus roots under T. harzianum + F. solani (T + F) treatment and F. solani (F) treatment were sampled and subjected to transcriptomic analysis. A differential expression analysis revealed that 6361 differentially expressed genes (DEGs) responded to T. harzianum induction. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of the 6361 DEGs revealed that the genes significantly clustered into resistance-related pathways, such as the plant–pathogen interaction pathway, phenylpropanoid biosynthesis pathway, flavonoid biosynthesis pathway, isoflavonoid biosynthesis pathway, mitogen-activated protein kinase (MAPK) signaling pathway, and plant hormone signal transduction pathway. Pathway analysis revealed that the PR1, formononetin biosynthesis, biochanin A biosynthesis, and CHIB, ROS production, and HSP90 may be upregulated by T. harzianum and play important roles in disease resistance. Our study further revealed that the H₂O₂ content was significantly increased by T. harzianum induction. Formononetin and biochanin A had the potential to suppress F. solani. Weighted gene coexpression network analysis (WGCNA) revealed one module, including 58 DEGs associated with T. harzianum induction. One core hub gene, RPS25, was found to be upregulated by T. harzianum, SA (salicylic acid) and ETH (ethephon). Overall, our data indicate that T. harzianum can induce induced systemic resistance (ISR) and systemic acquired resistance (SAR) in A. mongholicus. The results of this study lay a foundation for a further understanding of the molecular mechanism by which T. harzianum induces resistance in A. mongholicus. Full article

To investigate the impact of blending natural gas with hydrogen on the combustion performance of partially premixed gas water heaters, a framelet-generated manifold (FGM) was employed for lower-order simulation of combustion processes. Coupled with the 30-step methane combustion mechanism simplified by GRI3.0, a three-dimensional computational fluid dynamics (CFD) simulation of the combustion chamber of a partially premixed gas water heater was carried out. A numerical simulation was performed to analyze the combustion process of a mixture including 0–40% natural gas and hydrogen in the combustion chamber of a partially premixed gas water heater. The results indicate that the appropriate hydrogen blending ratio for some premixed gas water heaters should be less than 20%. Furthermore, it was observed that after blending hydrogen, there was a significant increase in the combustion temperature of the water heater. Additionally, there was a slight increase in NOx. Full article

The Earth rotation parameters (ERP) play a crucial role in defining the global reference frame and the Global Navigation Satellite System (GNSS) is one of the important tools used to obtain ERP, including polar motion (PM), its rates, and length of day (LOD). The latest IGS Repro3 ERP products, which provided the IGS contribution to the latest ITRF2020, were generated without consideration of the Beidou Navigation Satellite System (BDS) observations. The global BDS, namely the BDS-3 constellation, has been completely constructed from July 2020 and the observing stations are evenly distributed globally now. Two couple dual-frequency combinations, including the B1I/B3I and B1C/B2a combinations, are commonly used for BDS-3 ionosphere-free combination usage. With the goal of identifying the optimal dual-frequency combination for BDS-3 ERP estimates for the future ITRF definition with a consideration of BDS-3, this research evaluated the performance of ERP estimation using B1I/B3I and B1C/B2a combinations. Firstly, we conducted a comparison of the ambiguity resolutions. The mean percentage of successfully resolved ambiguities for the BDS-3 B1C/B2a combination is 86.5%, surpassing that of B1I/B3I. The GNSS satellite orbits and ERP were estimated simultaneously, thus the accuracy of orbits could also reflect the performance of the ERP estimates. Subsequently, we validated the orbits of 22 BDS-3 Medium Earth Orbit (MEO) satellites using Satellite Laser Ranging (SLR), and the root mean square error (RMS) of the SLR residuals for the 3-day arc orbit with B1C/B2a signals was 5.72 cm, indicating superior accuracy compared with the B1I/B3I combination. Finally, we compared the performance of ERP estimation, considering both internal and external accuracy. For the internal accuracy, B1C/B2a-based solutions demonstrated a reduction in mean formal errors of approximately 17% for PM, 22% for LOD, and 21% for PM rates compared with B1I/B3I-based solutions. In terms of external accuracy, we compared BDS-3-derived ERP estimates with the IERS 20C04 products. The B1C/B2a combination exhibited a slightly better standard deviation performance and a significant reduction in mean bias by 56%, 54%, 39%, 64%, and 23% for X, Y polar motion, X, Y polar motion rates, and LOD, respectively, compared with B1I/B3I solutions. In conclusion, the results highlight the excellent signal quality for BDS-3 B1C/B2a and its superiority in ERP estimation when compared with the B1I/B3I combination. Full article