Compounds

The parameters that determine practical applications of oxide ferrimagnets are the values of saturation magnetizations and the magnitudes and signs of the magnetocrystalline anisotropy fields. Measuring magnetocrystalline anisotropy fields using ferromagnetic resonance (FMR) on single-crystal or textured polycrystalline hexaferrite samples is straightforward. However, these methods are not applicable to hexaferrite, which are typically synthesized as macroscopically magnetically isotropic polycrystalline or powder samples. This paper discusses two methods for calculating the components of the permeability tensor of polycrystalline (or powder) hexaferrites within the independent grain approach. The methods are described for experimentally determining the magnitudes and signs of magnetocrystalline anisotropy fields and magnetomechanical ratios for such materials, based on FMR curves measured at various frequencies. The proposed method is illustrated by the results of an FMR study of a Y-type polycrystalline Ba₂Ni_2−xCu_xFe₁₂O₂₂ (0.0 ≤ x ≤ 2.0) system, synthesized using a standard ceramic method. The measurements were performed on spherical samples in the frequency range of 36–50 GHz. The method allows one to evaluate the magnetocrystalline anisotropy fields and magnetomechanical ratios of both the target Y-phase and impurity phases. The phase composition estimates obtained from FMR data were compared with the results of X-ray phase analysis. It has been shown that up to x = 1.8, these materials are ferroxplana-type hexaferrites, while the hexaferrite Ba₂Cu₂Fe₁₂O₂₂ exhibits the easy-axis type of magnetocrystalline anisotropy.

Spodoptera frugiperda is a polyphagous pest of global significance, causing substantial yield losses in maize and other staple crops, which has intensified the search for sustainable alternatives to synthetic insecticides. The Asteraceae family has emerged as a promising source of botanical insecticides, but a comprehensive synthesis of its true potential including biological efficacy, chemical basis and acute oral toxicity in mammalian models remains lacking. This review critically examines the biological activity of Asteraceae extracts against S. frugiperda from the 2021 to 2026 period and their phytochemical profiles and acute oral toxicity in mammals. Our analysis reveals three major findings. First, essential oils exhibit the highest insecticidal potency, but they also present the most concerning mammalian acute oral toxicity profiles. Second, although 57 major constituents—including terpenoids, phenolic acids, flavonoids, and fatty acid derivatives— have been identified, fewer than 13% have been individually evaluated against this pest, introducing substantial uncertainty in attributing activity to specific compounds. Third, most mammalian toxicity studies report only limited LD₅₀ thresholds (e.g., >2000 mg kg⁻¹ BW), preventing accurate GHS classification and regulatory positioning. Therefore, realising the potential of Asteraceae based insecticides requires not only the discovery of bioactive extracts but also rigorous, integrated toxicity and phytochemical characterisation.

Medicinal plants are valuable sources of structurally diverse bioactive compounds with potential antiviral properties, although their chemical complexity complicates candidate prioritization. This study developed a hierarchical computational framework to prioritize metabolites from Uvaria chamae against Ebola virus glycoprotein GP1–GP2 (PDB ID: 5F1B) and SARS-CoV-2 papain-like protease PLpro (PDB ID: 7CMD). A library of 105 phytochemicals was evaluated using statistical analyses, molecular docking, Prime MM-GBSA, ADMET and medicinal chemistry assessments, induced-fit docking, 100 ns molecular dynamics simulations, and conceptual DFT. Although overall docking-score distributions did not differ significantly among plant organs, top-ranked candidates were predominantly associated with roots and stems, while flavonoids, acetogenins, and phenolics showed the most favorable profiles. Proanthocyanidin emerged as the leading Ebola GP candidate (Prime MM-GBSA ΔGbind = −45.66 kcal/mol), whereas uvangoletin showed the most balanced PLpro profile (−41.69 kcal/mol). MD simulations with toremifene and GRL0617 as references supported structural persistence of the prioritized complexes. DFT analysis yielded HOMO–LUMO gaps of 5.37 eV for proanthocyanidin and 4.81 eV for uvangoletin. This framework enables reproducible prioritization of plant organs, phytochemical classes, and metabolites before experimental validation.