This paper presents a novel collocation-based numerical method for solving linear Volterra integro-differential equations with highly oscillatory trigonometric kernels. The proposed approach combines a piecewise polynomial collocation scheme with a two-point generalized quadrature rule, effectively reducing the original problem to a system of linear algebraic equations. A rigorous convergence analysis is conducted, establishing explicit error bounds that reveal the influence of both the oscillation frequency ω and the discretization step size on the error bound. The efficacy of the method is validated through numerical experiments, including problems whose exact solutions are known or unknown, as well as cases where the exact solution is smooth or non-smooth. The analysis further identifies key limitations, including the assumption of no stationary points in the oscillator, the linearity of the underlying problem, and the smoothness requirements, which are addressed as directions for future research.
Construction on soft, highly compressible soils increasingly requires reliable ground improvement solutions. Among these, Rigid Inclusions (RIs) have emerged as one of the most efficient soil-reinforcement techniques. This paper synthesizes evidence from over 180 studies to provide a comprehensive state-of-the-art review of RI technology encompassing its governing mechanisms, design methodologies, and field performance. While the static behavior of RI systems has now been extensively studied and is supported by international design guidelines, the response under cyclic and seismic loading, particularly in liquefiable soils, remains less documented and subject to significant uncertainty. This review critically analyzes the degradation of key load-transfer mechanisms including soil arching, membrane tension, and interface shear transfer under repeated loading conditions. It further emphasizes the distinct role of RIs in liquefiable soils, where mitigation relies primarily on reinforcement and confinement rather than on drainage-driven mechanisms typical of granular columns. The evolution of design practice is traced from analytical formulations validated under static conditions toward advanced numerical and physical modeling frameworks suitable for dynamic loading. The lack of validated seismic design guidelines is high-lighted, and critical knowledge gaps are identified, underscoring the need for advanced numerical simulations and large-scale physical testing to support the future development of performance-based seismic design (PBSD) approaches for RI-improved ground.
Petunia hybrida is a widely cultivated ornamental species valued for its aesthetic appeal and economic importance, yet its growth and floral quality are highly vulnerable to abiotic stresses such as soil alkalinity and iron (Fe) deficiency. These stressors often co-occur in calcareous soils and urban landscapes, leading to impaired nutrient uptake, chlorosis, reduced photosynthetic efficiency, oxidative damage, and diminished biomass and flower production. In this study, we examined the potential of resveratrol, a multifunctional polyphenolic compound with antioxidant and regulatory properties, to mitigate the detrimental effects of alkalinity-induced Fe deficiency in Petunia hybrida ‘Supercascade Rose’ under soilless culture conditions. A factorial experiment was conducted using two nutrient solution pH levels (6.0 and 8.3), two Fe concentrations (15 and 1.5 mg L⁻¹), and three foliar-applied resveratrol concentrations (0, 100, and 200 µM). Alkaline pH combined with Fe deficiency significantly suppressed morphological traits, pigment content, and antioxidant enzyme activities. However, foliar application of resveratrol, particularly at 100 µM, effectively alleviated these negative impacts by enhancing chlorophyll and carotenoid contents, anthocyanin accumulation, total phenolic and flavonoid levels, and the activities of catalase (CAT) and ascorbate peroxidase (APX). Resveratrol also improved Fe uptake and maintained photosynthetic performance, resulting in increased biomass accumulation and enhanced floral quality. These findings underscore the potential of resveratrol as a bio-based stress-mitigating agent for enhancing plant resilience and ornamental value under alkaline and Fe-deficient conditions. Incorporating such compounds into ornamental horticultural practices may offer sustainable solutions for managing plant stress in suboptimal environments.
Chitosan and functionalized chitosans with 3, 4-dihydroxybenzoyl groups (CS-DHBA) and 3,4, 5-trihydroxybenzoyl groups (CS-THBA) were exposed to ultraviolet (UV) irradiation. The physicochemical and mechanical properties of chitosan (CS), CS-DHBA, and CS-THBA, including chemical structures, molecular weights, polydispersity index, intrinsic viscosity, and mechanical properties before and after UV-irradiation, were investigated and compared. The results showed that the molecular weight of chitosan decreased from 782,401 to 522,012 g/mol with increasing UV irradiation time. In contrast to chitosan, the molecular weight of CS-DHBA and CS-THBA increased to 826,187 g/mol and 845,310 g/mol, respectively, with increasing UV irradiation time. In addition, the polydispersity index (Mw/Mn) of chitosan decreased from 7.41 to 5.62 after 12 h of UV irradiation, but the polydispersity index of CS-THBA increased from 9.84 to 9.94. The surface morphology and structural analysis of UV-irradiated chitosan, CS-DHBA, and CS-THBA by SEM, FT-IR, and XRD confirmed that the chemical structure of irradiated chitosan was not significantly changed. In contrast, the chemical structures of irradiated CS-DHBA and CS-THBA were altered. The tensile strength (TS) of chitosan films decreased after 12 h of radiation, but UV-irradiated CS-DHBA and CS-THBA showed a significant adhesive capacity and enhanced TS.
This study examined the role of 24-epibrassinolide (EBL) in mitigating drought-induced oxidative stress in rye (Secale cereale L.) through comprehensive analyses of antioxidant enzyme activities, stress-responsive gene expression, and oxidative stress markers. Rye seedlings were subjected to polyethylene glycol (PEG)-induced water deficit (0
