Wide-stopband plasmonic filters are critical components for the development of compact mid-infrared (MIR) photonic systems. In this study, we propose a geometrically tunable wide-stopband plasmonic filter based on a meta-insulator-metal (MIM) waveguide integrated with dual resonator cavities. The optical response of the proposed structure is numerically investigated using the twodimensional finite-difference time-domain (2D-FDTD) method. We systematically analyze the influence of key geometric parameters, specifically the resonator height (H2) and inter-cavity distance (D), on the stopband characteristics. Our results demonstrate that the symmetric dual-cavity configuration provides effective control over both the stopband bandwidth and central wavelength. Consequently, the proposed design achieves a significantly broadened stopband while preserving structural compactness and high transmission selectivity, making it a highly promising candidate for integration into advanced MIR photonic circuits and sensing systems.
This study investigated the effect of solvent polarity on extraction yield, phytochemical composition, antioxidant activity, and α-amylase inhibition of Elaeagnus angustifolia L. leaf extracts to evaluate their antidiabetic potential. Extraction yields varied with solvent polarity, with the hydroethanolic extract showing the highest (18.00%) and n-hexane the lowest (0.05%) yield. The n-butanol and ethyl acetate fractions contained the most phenolics (309.05 and 290.97 mg GAE/g), ethyl acetate was the richest in flavonoids (102.11 mg QE/g), and tannins were concentrated in dichloromethane (66.24 mg CE/g). HPLC revealed solvent-specific profiles: rutin and gallic acid dominated in n-butanol, quercetin in ethyl acetate, and 4-hydroxybenzoic and ferulic acids in dichloromethane, while chicoric acid appeared in hydroethanolic and n-hexane extracts. Antioxidant assays (DPPH, ABTS, and FRAP) showed strong activity in polar extracts, particularly hydroethanolic and ethyl acetate fractions. The n-hexane extract exhibited the highest α-amylase inhibition (IC50 = 36.70 µg/mL), surpassing acarbose (IC50 = 126.14 µg/mL), while other fractions were inactive (IC50 > 400 µg/mL). Molecular docking highlighted rutin, chlorogenic acid, and chicoric acid as potential enzyme binders. These findings demonstrate the chemical diversity and significant bioactivities of E. angustifolia leaves, supporting their potential as natural antidiabetic agents.
The increasing interest in sustainable natural antioxidants has highlighted olive by-products as valuable bioresources. This study aimed to assess and compare the phenolic composition, antioxidant potential, and protective effects of phenolic extracts obtained from the pulp and leaves of Olea europaea L. (Sigoise variety) against oxidative hemolysis in human erythrocytes. Phenolic compounds were extracted by hydroalcoholic maceration and characterized using HPLC–PDA-ESI/MS analysis. The olive leaf extract contained markedly higher total phenolic (77.7 ± 0.55 mg GAE/g dw) and flavonoid (39.72 ± 0.12 mg QE/g dw) levels than the olive pulp extract (43.22 ± 0.10 mg GAE/g dw and 27.69 ± 0.68 mg QE/g dw, respectively). Chromatographic profiling revealed hydroxytyrosol, oleuropein, tyrosol, caffeic acid, and luteolin derivatives as predominant constituents. Antioxidant assays demonstrated strong ferric reducing (FRAP), DPPH radical scavenging, and hydrogen peroxide neutralizing activities, showing a strong correlation (r > 0.98) with total phenolic content. The leaf extract exhibited higher antioxidant efficiency (DPPH IC₅₀ = 98.94 µg/mL) than the pulp extract (IC₅₀ = 174.11 µg/mL). In vitro experiments on erythrocytes confirmed the extracts’ capacity to inhibit oxidative hemolysis, preserve catalase and glutathione levels, reduce lipid peroxidation, and maintain oxyhemoglobin stability. Microscopic observations further supported their membrane-protective properties. Overall, these results demonstrate that both olive pulp and olive leaves possess strong antioxidant and cytoprotective potentials, underscoring their value as natural sources of bioactive compounds for use in functional foods, nutraceuticals, and pharmaceuticals, while contributing to the sustainable valorization of olive processing by-products.
Pharmaceutical contamination of aquatic systems poses an increasing environmental concern due to the persistence, bioactivity, and incomplete removal of these compounds by conventional wastewater treatment processes. This study investigates the adsorptive removal of three structurally distinct pharmaceuticals: ketotifen fumarate (KF), doxycycline hyclate (DXC), and nystatin (Nyst), using raw bentonite (RB). By combining batch experiments with an interpretable machine learning (ML) framework, adsorption kinetics, equilibrium, and thermodynamics were evaluated. Additionally, four Ant Lion Optimizer (ALO)-optimized models: Artificial Neural Network (ANN), Support Vector Regression (SVR), Random Forest (RF), and eXtreme Gradient Boosting (XGBoost), were employed to predict adsorption capacity under diverse conditions. RB exhibited high adsorption capacities: 178.86 ± 1.26 mg/g for KF, 222.91 ± 2.02 mg/g for DXC, and 190.25 ± 2.86 mg/g for Nyst. Adsorption equilibrium was best described by the Freundlich isotherm, indicating multilayer adsorption on a heterogeneous surface. Thermodynamic and spectroscopic analyses revealed a dual mechanism involving electrostatic attraction, hydrogen bonding, cation exchange, and van der Waals interactions, with DXC and Nyst adsorption being endothermic and KF adsorption exothermic. SHAP (SHapley Additive exPlanations) analysis identified adsorbent dosage, initial concentration, and pH as dominant operational factors, while the molecular descriptor nC (number of carbon atoms) emerged as key to differentiating pharmaceuticals, linking larger molecular size to stronger adsorption. The XGBoost model achieved the highest accuracy (R2 = 0.972, RMSE = 0.1225), demonstrating robust generalizability. These findings highlight RB as a low-cost, scalable adsorbent and establish an interpretable ML approach capable of linking molecular structure to adsorption behavior.
The use of expanded clay as a supplementary cementitious material in mortar offers potential for reducing carbon dioxide (CO2) emissions and improving thermal insulation, but is limited by reduced mechanical performance. This study investigates combined effects of expanded clay incorporation (0%, 10%, 20%, 30% cement replacement) and elevated temperature exposure (25°C–800°C) on quarry sand-based mortars. Mechanical properties, mass loss, and microstructural changes were evaluated, along with statistical and sustainability assessments. Results show increasing expanded clay content reduced bulk density by 1.27%–2.14% and improved thermal insulation by 13.47%. Compressive and flexural strength decreased by 2.88%–6.97% at ambient temperature for 30% replacement. After high-temperature exposure, expanded clay mortars showed improved thermal stability, retaining 47.3%–61.21% of original strength at 800°C against 32.6%–33.3% for control. Performance declined significantly at 800°C due to cracking, void formation, and microstructural damage, with ultrasonic pulse velocity values below 3000 m/s. Elastic modulus variation was similar across all mortars. Statistical analysis confirmed significant effects of both variables (p < 0.05). Partial cement replacement reduced carbon dioxide emissions by 15%–30%. Overall, optimised expanded clay use balances mechanical performance, thermal resistance, and sustainability for low-carbon, temperature-resistant mortar systems.
