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  • 2025

    Microbial communities in subsurface coastal sediments are highly diverse and play an important role in nutrient cycling. While the major fraction of microorganisms in sandy sediments lives as epipsammon (attached to sand grains), only a small fraction thrives in the interstitial porewaters. So far, little is known about the composition of these free-living microbial communities. In the subsurface of the sandy beach, investigated in this study, we compared the archaeal and bacterial community structures within sediments and corresponding porewaters applying 16S rRNA gene sequencing. We found that the free-living prokaryotes only had a proportion of about 0.2–2.3% of the bulk communities, depending on the pore space. The interstitial microbial communities showed a small overlap with the attached fraction of 4–7% ASVs, and comprised a unique composition of 75–81% ASVs found exclusively in the porewaters. They were more diverse than the respective sediment-attached fraction and showed a much higher archaea-to-bacteria ratio. The archaea were mainly affiliated to Nanoarchaeota of the DPANN superphylum, with a relative abundance up to 50% of the interstitial communities. The bacterial fraction included several species related to the Candidate Phyla Radiation (CPR). Both prokaryotic lineages are known to have small cell sizes, comprising not-yet cultured species with unidentified metabolic functions. Our findings were supported by the investigation of an adjacent tidal flat, showing a similar trend. Thus, our results indicate the presence of distinct interstitial microbial communities in the subsurface of coastal sediments. This natural enrichment of not-yet cultured Nanoarchaeota and members of the CPR provides the opportunity for targeted metagenomic analyses or even isolating members of these groups for further metabolic characterization.
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  • 2025


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    • Pub. Date : 2025
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  • 2025


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    • Pub. Date : 2025
    • Page : pp.101741-101741
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  • 2025

    Abstract Bovine enterovirus, a member of the Enterovirus genus in the Picornaviridae family, causes severe digestive and respiratory illnesses in cattle. These illnesses threaten the healthy development of the cattle industry. Innate immunity plays a critical role in resisting viral infections, but viruses also use various strategies to evade or counteract the host’s immune system. The mechanisms by which bovine enteroviruses evade the host immune response and promote their replication remain unclear. This study used the HY12 strain of enterovirus as a model to investigate its interaction with both bovine enterovirus and its host. Our findings indicate that bovine enterovirus promotes the replication of HY12 by disrupting the NF-κB pathway. Here, one strategy was to down-regulate the IΚBΚB expression to inhibit the activation of NF-κB. Another approach was to directly interact with p65 to reduce the dimerisation of p65/p50 and inhibit the phosphorylation and nuclear translocation of p65. Our study’s results show that 2C’s N-terminal 1-121 aa is essential for 2C-mediated inhibition of the NF-κB signalling pathway, and four amino acids (position 118-121 aa) are the interaction site of 2C with p65. This report is the first on BEV 2C protein promoting virus replication through new strategies, which provides novel insights into the understanding of enterovirus pathobiology and the development of drugs against BEV.
    • Book : 56(1)
    • Pub. Date : 2025
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  • 2025

    Seismic correlation can affect seismic probabilistic risk assessment results when components within the system have similar dynamic characteristics. While the fragility assessment methodology is well established, researches to evaluate and apply seismic correlation in fragility are still in progress. In this study, the seismic correlation coefficient (SCC) was quantitatively analyzed based on fragility assessment methods. In order to evaluate the SCC of several random variables associated with structure response in fragility assessment, a numerical analysis model of the structure was constructed and statistical analysis of the numerical results was performed. The SCC of the floor responses of the structural model considering random variables was evaluated from two perspectives.The first perspective involved applying variables individually or simultaneously when performing probabilistic structural analysis. The second perspective aimed to assess whether simplification of the structural analysis model affects the SCC. For this purpose, SCCs were calculated for each method and applied to a simplified failure sequence model to compare the combined fragility curves. The results of this study demonstrate the applicability of separation of variables method to the evaluation and generalization of the SCC for random variables of the fragility curve.
    • Book : 57(3)
    • Pub. Date : 2025
    • Page : pp.1-13
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  • 2025

    Abnormal detection in surveillance cameras never fails to be a crucial and challenging task across many fields, aimed at protecting the property safety of citizens and society from abnormal events. Currently, the most common solution for abnormal detection proves to be the combination of autoencoder models and unsupervised training scheme. Due to the scarcity of abnormal samples, all training samples are typically treated as normal samples when constructing the autoencoder calculation models, which generate reconstructed video frames with the same dimension as input data. In this approach, the identification of testing samples is determined by calculating the reconstruction errors between raw and reconstructed video frames. However, such calculation frameworks turn out to be unpractical for nuclear security, as the threshold value of reconstruction errors is overly sensitive, often leading to extreme and unacceptable results. In this manuscript, a novel framework for abnormal detection in nuclear security is proposed. Unlike common unsupervised training scheme, this approach constructs two label-specific autoencoders, while one is trained exclusively with normal samples and the other one is only fed with abnormal samples. Therefore, there is no need to predefine the threshold value for reconstruction errors, as it is replaced by comparing the two label-specific reconstruction errors. Besides, two training schemes for the label-specific autoencoders are proposed and analyzed. Based on a self-collected dataset for nuclear security, the results show that the proposed framework is both practical and appliable, with both training schemes achieving an acceptable accuracy of 0.8182.
    • Book : 57(3)
    • Pub. Date : 2025
    • Page : pp.1-9
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  • 2025

    Abstract Plasma disruptions present a significant challenge to the viability of fusion energy production in tokamak reactors. Among disruption mitigation techniques, shattered pellet injection (SPI) has emerged as a promising approach. The results presented in this paper show novel findings of the impact of nitrogen and neon seeding on the disruption mitigation sequence following SPI on the Joint European Torus (JET). This study exposes an order of magnitude reduction in pre-thermal quench duration for highly seeded plasmas and pure deuterium SPI, a result with significant implications for staggered SPI schemes currently under development. Conversely, no reduction in disruption thermal load mitigation efficacy was observed for single neon and hydrogen mixed SPI across a range of seeding levels, indicating the robustness of this approach. A novel pathway for thermal load mitigation and enhanced runaway electron avoidance with pure deuterium SPI into strongly seeded plasmas is also presented.
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    • Pub. Date : 2025
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  • 2025

    This paper investigates the challenges and solutions associated with integrating a hydrogen-generating nuclear-renewable integrated energy system (NR-IES) under a transactive energy framework. The proposed system directs excess nuclear power to hydrogen production during periods of low grid demand while utilizing renewables to maintain grid stability. Using digital real-time simulation (DRTS) in the Typhoon HIL 404 model, the dynamic interactions between nuclear power plants, electrolyzers, and power grids are analyzed to mitigate issues such as harmonic distortion, power quality degradation, and low power factor caused by large non-linear loads. A three-phase power conversion system is modeled using the Typhoon HIL 404 model and includes a generator, a variable load, an electrolyzer, and power filters. Active harmonic filters (AHFs) and hybrid active power filters (HAPFs) are implemented to address harmonic mitigation and reactive power compensation. The results reveal that the HAPF topology effectively balances cost efficiency and performance and significantly reduces active filter current requirements compared to AHF-only systems. During maximum electrolyzer operation at 4 MW, the grid frequency dropped below 59.3 Hz without filtering; however, the implementation of power filters successfully restored the frequency to 59.9 Hz, demonstrating its effectiveness in maintaining grid stability. Future work will focus on integrating a deep reinforcement learning (DRL) framework with real-time simulation and optimizing real-time power dispatch, thus enabling a scalable, efficient NR-IES for sustainable energy markets.
    • Book : 18(4)
    • Pub. Date : 2025
    • Page : pp.937-937
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  • 2025

    Human reliability analysis (HRA) plays a vital role in probabilistic risk assessment (PRA) by quantifying the reliability and safety of complex technical systems through the estimation of human error probabilities (HEPs).Standardized plant analysis risk human (SPAR-H) reliability analysis is widely used for HRA; it adjusts the nominal HEP by assigning different multipliers to the performance shaping factors (PSFs). However, SPAR-H cannot capture the time-varying nature of HEPs; therefore, it cannot realistically respond to the accumulation and fluctuation of human risk factors across the mission. Hence, this study proposed a systematic method of dynamic HRA. It includes decision-making trial and evaluation laboratory-interpretative structural modeling (DEMATEL-ISM) to qualitatively and quantitatively analyze the hierarchical causality among the PSFs and their influence on each other based on their relative relationship in SPAR-H and construct hierarchical causality diagrams among the PSFs. Additionally, it uses a system dynamics method in conjunction with the analysis of timedependent PSFs based on the hierarchical causality diagrams of PSFs to respond to the time-varying nature of HEPs. The simulation and rationale check results of the cases show that the proposed dynamic HRA method can realize a more realistic and dynamic estimation of HEPs.
    • Book : 57(3)
    • Pub. Date : 2025
    • Page : pp.1-12
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  • 2025

    High-quality diamond-like carbon (DLC) films are renowned for their exceptional hardness, low friction coefficient, and superior chemical stability. These properties make DLC films exceptionally suitable for protective coatings in optical, mechanical, aerospace, and military applications. Thick DLC films with outstanding mechanical properties were deposited on DC53 die steel using a mixed energy carbon plasma generated by a filtered cathodic vacuum arc (FCVA) device. The structural, mechanical, tribological, and optical properties of the films were tested by Raman, surface morphology instrument, Vickers Indenter, tribometer, and UV-VIS spectrophotometry. The results indicated that 14 µm tetrahedral amorphous carbon (ta-C) films with a good combination with DC53 die steel substrate were obtained. The hardness was 9415 HV, which is close to that of diamond films. The fracture toughness was 4 MPa·m1/2. The friction coefficient was 0.0898, and the optical band gap was 3.12 eV.
    • Book : 15(2)
    • Pub. Date : 2025
    • Page : pp.241-241
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