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Elevated near-surface ozone (O3) concentrations have surpassed the tolerance limits of plants, significantly impacting crop growth and yield. To mitigate ozone pollution, plants must evolve a rapid and effective defense mechanism to alleviate ozone-induced damage. DNA methylation, as one of the most crucial epigenetic modifications, plays a pivotal role in maintaining gene stability, regulating gene expression, and enhancing plant resilience to environmental stressors. However, the epigenetic response of plants to O3 stress, particularly DNA methylation variations and their intergenerational transmission, remains poorly understood. This study aims to explore the epigenetic mechanisms underlying plant responses to ozone stress across generations and to identify potential epigenetic modification sites or genes crucial in response to ozone stress. Using Open Top Chambers (OTCs), we simulated ozone conditions and subjected foxtail millet to continuous ozone stress at 200 nmol mol-1 for two consecutive generations (S0 and S1). Results revealed that under high-concentration ozone stress, foxtail millet leaves exhibited symptoms ranging from yellowing and curling to desiccation, but the damage in the S1 generation was not more severe than that in the S0 generation. Methylation Sensitive Amplified Polymorphism (MSAP) analysis of the two generations indicated that ozone stress-induced methylation variations ranging from 10.82% to 13.59%, with demethylation events ranged from 0.52% to 5.58%, while hypermethylation occurred between 0.35% and 2.76%. Reproductive growth stages were more sensitive to ozone than vegetative stages. Notably, the S1 generation exhibited widespread demethylation variations, primarily at CNG sites, compared to S0 under similar stress conditions. The inheritance pattern between S0 and S1 generations was mainly of the A-A-B-A type. By recovering and sequencing methylation variant bands, we identified six stress-related differential amplification sequences, implicating these variants in various biological processes. These findings underscore the potential significance of DNA methylation variations as a critical mechanism in plants' response to ozone stress, providing theoretical insights and references for a comprehensive understanding of plant adaptation mechanisms to ozone stress and the epigenetic role of DNA methylation in abiotic stress regulation. [ABSTRACT FROM AUTHOR]

The exploitation of effective and nontoxic materials with antioxidant activity to mitigate or inhibit the damage caused by elevated levels of free radicals has attracted considerable attention across diverse fields. Herein, this study demonstrates that a biocompatible MgAl‐layered double hydroxide (LDH) can be activated for multiple types of free radical scavenging with unexpected activity through amorphization (a‐MgAl‐LDH). Detailed characterization reveals that numerous oxygen defects are introduced after amorphization. Mechanistic studies and theoretical simulations indicate that amorphization‐induced oxygen defects in a‐MgAl‐LDH promote radical adsorption and reduce the reaction energy barriers, thereby resulting in enhanced radical scavenging activities. Consequently, a‐MgAl‐LDH demonstrated remarkable efficiency in mitigating the oxidative injury induced by Rosup in cells and provided thermal stabilization of polyvinyl chloride against degradation. This study demonstrates the transformation of inert MgAl‐LDH into a promising, nontoxic, and cost‐effective nano‐antioxidant option for antioxidative therapy or polymer stabilization and highlights the significance of crystallinity engineering of nanomaterials for efficient free radical scavenging. [ABSTRACT FROM AUTHOR]

The plant kingdom harbors the Plasmodesmata Callose Binding Protein (PDCB) gene family, which plays essential roles in plant growth, development, environmental adaptation, and yield. PDCB genes are closely involved in regulating cell-to-cell communication and controlling callose deposition at plasmodesmata (PD) throughout the whole plant. Remarkably, their functions remain largely unknown in many crops, including maize. This study sought to identify the members of the PDCB gene family within the maize genome and analyze their physicochemical properties and expression patterns. Utilizing bioinformatics methodologies, a comprehensive genome-wide analysis of the PDCB gene family was performed. The findings revealed that PDCB genes were highly abundant in maize, with a total of 56 PDCB genes identified and categorized into six distinct groups. Members of the PDCB family were dispersed across all chromosomes. The PDCBs within each group exhibited significant similarity in their conserved motifs and gene structures; all members contained the X8 domain, comprising one to five exons, while displaying a straightforward genomic structure. Numerous cis-acting elements associated with plant growth and development, light response, stress-associated responses, and plant hormones were identified in the promoter regions of PDCB genes. Moreover, the PDCBs exhibited diverse expression patterns across various tissues. This study improves the comprehension of the PDCB gene family and provides a robust foundation for further research on maize. [ABSTRACT FROM AUTHOR]

The embedment length (EL) of full-grouting rock bolts is a core factor in rock bolt reinforcement. Therefore, understanding the influence of EL on the reinforcement performance of rock bolts benefits the rock reinforcement quality. To realise this purpose, this paper adopted the numerical modelling method. In this numerical modelling method, the structural elements of modified piles were used. The elastic debonding law was incorporated into the modified pile elements to model the debonding behaviour of the surface between rock bolts and grout. The results showed that the sliding of modified pile elements had a marginal influence on the reinforcement performance of rock bolts. Moreover, the EL has a paramount influence on the reinforcement performance of rock bolts. Before the rock bolts reached the largest anchorage force, there was a linear relation between the largest anchorage force and the EL. It was effective to use the linear regression analysis method to predict the critical EL of rock bolts. This finding was also applicable to fibre-reinforced polymer (FRP) rock bolts. Additionally, the rock bolt type had a paramount influence on the reinforcement performance of rock bolts. Before the rock bolts reached the largest anchorage force, metal rock bolts showed much larger initial stiffness than FRP rock bolts. [ABSTRACT FROM AUTHOR]