Search Results (1,996)

Dynamic covalent hydrogels exhibiting multi-responsive and antibacterial properties offer significant potential for biomedical applications, including smart wound dressings and controlled drug delivery. Herein, a series of amphiphilic quaternized copolymers (Q-C8PEG-n) with tunable quaternization degrees was synthesized from C8PEG via iodomethane addition and characterized by ¹H NMR, COSY, FTIR, UV-vis spectroscopy, DLS, TEM, and zeta potential analyses, confirming successful quaternization and micelle formation. These copolymers displayed thermosensitive behavior, with cloud point temperatures increasing due to enhanced hydrophilicity. Q-C8PEG-3 micelles, incorporating diethanolamine units, were crosslinked with phenylboronic acid-grafted hyaluronic acid (HA-PBA) to yield dynamic covalent hydrogels (Gel) through reversible boronic ester bonds stabilized by B-N coordination. The Gel exhibited multi-responsiveness, undergoing degradation in acidic or alkaline conditions and exposure to glucose or H₂O₂. SEM confirmed a porous microstructure, enabling efficient drug encapsulation, as demonstrated by the release of Nile red (NR). In vitro antibacterial tests revealed enhanced post-quaternization efficacy, with the Gel showing strong activity against S. aureus. This micelle-crosslinked platform synergistically combines tunable stimuli-responsiveness with inherent antibacterial properties, holding promise for applications in wound healing and tissue engineering. Full article

Listeria monocytogenes is a foodborne pathogen of significant concern. While it typically causes mild, self-limiting gastroenteritis, it poses a much higher threat to immunocompromised individuals and pregnant women, where it may lead to miscarriage. Numerous outbreaks have been linked to ready-to-eat foods. Although heat treatment is commonly used for microbial decontamination, it is unsuitable for fresh produce such as fruits and vegetables. Other physical (e.g., UV, gamma irradiation) and chemical (e.g., NaOCl, ozone) methods can compromise sensory qualities or face limited consumer acceptance. Photodynamic Inactivation (PDI) has emerged as a promising alternative, particularly when using natural photosensitizers. Because PDI efficacy depends on photosensitizer diffusion, there is a need to further explore how different and complex fruit surface structures may influence its performance. Three fruit models were therefore selected to represent distinct surface textures and were evaluated in situ: apples (smooth), strawberries (irregular), and kiwis (fuzzy and hairy surface). The influence of contamination order was also evaluated, as this factor is highly relevant to real-world supply-chain scenarios but has been largely overlooked in prior research. Additionally, the study investigated how the order of contamination affected the decontamination outcome. Sodium-magnesium-chlorophyllin (Na-Mg-Chl), an approved food additive (E140), was used as photosensitizer. Fruits were cut into 1 cm² squares and inoculated with L. monocytogenes. A 100 µM Na-Mg-Chl solution was applied either before or after bacterial inoculation. All samples were then illuminated using a 395 nm LED (radiant exposure 15 J/cm²). When L. monocytogenes was applied first, followed by the addition of Na-Mg-Chl, a 5.96 log reduction was observed in apples, a 5.71 log reduction in strawberries, and a 6.02 log reduction in kiwis. Conversely, when Na-Mg-Chl was applied prior to bacterial deposition, apples showed a 5.61 log reduction, strawberries demonstrated a 6.34 log reduction, and kiwis achieved the highest inactivation, at 6.74 log units. These results indicate that PDI consistently achieved substantial bacterial reductions across all fruit types, regardless of surface characteristics or application order. This supports PDI as a powerful method for fruit surface decontamination, reducing public health risks and economic losses while preserving product quality and consumer confidence. Full article

With the continuous rise in global plastic production and emissions, microplastics (MPs) have become ubiquitous across environmental compartments, including the atmosphere. Aging in natural settings substantially alters MP physicochemical properties and, in turn, their interactions with coexisting contaminants. Here, polyethylene (PE), polyethylene terephthalate (PET), and polystyrene (PS) were subjected to ultraviolet (UV)-accelerated aging and natural exposure in marine intertidal zones, freshwater lakes, and the atmosphere, and changes in their properties and tetracycline (TC) adsorption were systematically compared. Aging intensity followed the order seawater > freshwater > air. Fourier-transform infrared spectroscopy showed the formation and enrichment of oxygen-containing functional groups, and naturally aged samples exhibited stronger oxidation signatures than those aged solely under UV irradiation. Adsorption kinetics indicated higher equilibrium capacities and rate constants for aged MPs; after 324 h of UV exposure in seawater, TC adsorption on PE, PS, and PET increased by 64.6%, 56.6%, and 64.0%, respectively. Mechanistic analysis suggests that surface roughening, oxygenated functional groups, and enhanced negative surface charge collectively promote TC adsorption, dominated by electrostatic interactions and hydrogen bonding. These findings not only elucidate how different aging pathways modulate the interactions between MPs and pollutants but also offer new insights into assessing the carrier potential of microplastics in environments such as the atmosphere and their adsorption of other contaminants. Full article

Light is a crucial environmental regulator for Tricholoma giganteum (T. giganteum). This study investigated the effects of light quality and photoperiod on its growth, physiology, and nutritional composition. During the mycelial stage, blue light (BL) exposure for 5 d promoted the highest growth rate (0.74 mm d⁻¹, 45% higher than dark control, p < 0.05). Red light (RL) enhanced antioxidant capacity, elevating superoxide dismutase (SOD) activity to 240.20 U·mL⁻¹ (after 5 d) and DPPH radical-scavenging activity to 276.11% (after 3 d). Ultraviolet (UV) suppressed polyphenol oxidase (PPO) activity. BL also increased mycelial polysaccharide content (6.45 g·100 g⁻¹). In the fruiting stage, green light (GL) improved agronomic traits and first-grade yield (3.75 kg), while also promoting the accumulation of glutamate (4.39 g·100 g⁻¹), a key umami compound. Further photoperiod optimization revealed that 4 h of daily GL exposure shortened the fruiting cycle, achieved the highest biological efficiency (98.4%), and maximized both polysaccharide (38.17 g·100 g⁻¹) and glutamate contents (5.70 g·100 g⁻¹). These results recommend a two-stage lighting protocol: BL for mycelial growth and a 4 h daily GL for fruiting, providing a scientific basis for the industrial cultivation of T. giganteum. Full article

Indoor air quality (IAQ) in high-rise residential buildings is an increasing concern, especially in hot and humid climates where prolonged indoor exposure elevates health risks. This study evaluates the performance of Fresh Air Handling Units (FAHUs) using two complementary approaches: (1) real-time sensor data to quantify IAQ conditions and (2) occupant survey responses to capture perceived comfort and pollution indicators. The results show that floor level did not predict satisfaction, even though AQI data revealed clear differences between flats, suggesting perceptions are driven more by sensory cues than by actual pollutant levels. Longer weekday exposure emerged as a stronger predictor of dissatisfaction. These gaps between perceived and measured IAQ highlight the need for improved ventilation scheduling and greater occupant awareness. FAHUs were found to be inefficient, consuming 21–26% of total building energy while lacking pollutant-specific monitoring capabilities. To address these issues, the study recommends the integration of IoT-enabled sensors for real-time pollutant detection, enhanced facade sealing to minimize external infiltration, and the upgrade of filtration systems with HEPA filters and UV purification. Additionally, AI-driven predictive maintenance and automated ventilation optimization through Building Management Systems (BMS) are suggested. These findings offer valuable insights for improving IAQ management in high-rise buildings, with future research focusing on AI-based predictive modeling for dynamic air quality control. Full article

Additive manufacturing via LCD vat photopolymerisation enables direct bonding of photopolymer to textile substrates, but optimal processing parameters remain unclear. A 3 × 3 factorial design investigated the effects of layer thickness (0.01, 0.025, 0.05 mm) and UV exposure time (40, 80, 120 s) on the single-lap shear strength of woven fabric-photopolymer joints (65% polyester/35% cotton) using a novel pause-and-bond methodology, following the EN ISO 4587:2003 standard. Five replicate specimens per condition yielded 45 samples for mechanical testing. All specimens (45/45) exhibited adherend-limited failure within the textile substrate rather than at the polymer-textile interface, yielding consistent shear strengths of 1.38 ± 0.04 MPa (range: 1.30–1.45 MPa). Two-way ANOVA revealed no significant parametric effects (p > 0.05), indicating that interfacial bond strength consistently exceeded textile cohesive strength across all parameter combinations. The minimum resource-efficient condition (0.01 mm/40 s) achieves equivalent performance to higher-parameter combinations, enabling substantial process optimisation for textile-integrated photopolymer sandwich structures while reducing material and processing time requirements. Full article

This study is devoted to investigating the effect of aerosols on solar UV radiation. In the ultraviolet range, scattering processes are dominant and lead to a substantial contribution of diffuse UV radiation to the global UV irradiance. The paper introduces a method for estimating solar UV Index. The proposed method is first compared with other UV Index estimation methods and is subsequently applied to examine the influence of aerosols and ozone on solar UV radiation and on its diffuse component. Human skin exposure to diffuse solar UV radiation can be potentially harmful to health. Full article

Objective: The objective of our study was to synthesize and characterize silica–copper nanomaterials and to evaluate their biological properties (antibacterial, redox, cytotoxic, and ecotoxic) for potential applications. Methods and Results: Si/Cu-based materials were prepared by a sol–gel method. They were characterized by XRD, UV-Vis, and SEM-EDS. The antibacterial activity of the materials was evaluated against Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus), Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium), and yeasts (Candida albicans, Saccharomyces cerevisiae). The nanomaterial that was calcined at 500 °C exhibited greater antibacterial efficacy compared to the gel form. S. typhimurium demonstrated the highest susceptibility, whereas S. aureus and P. aeruginosa were the most resistant of the tested bacteria. Both yeasts exhibited comparable sensitivity (MBC = 1.0 mg/mL). The redox activity of both nanomaterials was tested at pH 7.4 (physiological) and 8.5 (optimal) by the activated chemiluminescent method. The nanocomposites significantly inhibited the free-radical and ROS generation. This presents them as redox regulators in living systems. The cytotoxic effects in normal BEAS-2B and tumor A549 human cell lines were assessed microscopically and by the cell viability neutral red uptake assay, CC₅₀ being evaluated. The observed effects suggest moderate, similar cytotoxicity in both cell lines. The ecotoxicity study using Daphnia magna showed an LC₅₀ of ~7–8 mg/L about Si/Cu/500. The LC₅₀ for Si/Cu (gel) was lower than 0.25 mg/L, indicating an increase in toxicity with increased exposure time. Conclusions: Possible applications of the newly synthesized nanomaterials include antimicrobial coatings, drug delivery systems, antioxidant additives in various formulations, and water purification. Full article

Polylactic acid (PLA) is a widely used bio-based polymer, although its application is limited by mechanical brittleness and low thermal resistance. PLA-based biocomposites reinforced with waste materials are gaining attention due to their sustainability, but their durability under degradation conditions remains a key concern. In this work, PLA biocomposites containing 0, 1, and 3% wt. of Olive-stone Biomass Ash (OBA) were manufactured and characterized both (1) after manufacture and (2) after laboratory-accelerated weathering (including UV exposure, heat, and humidity). The results obtained were analyzed to evaluate the influence of ash incorporation on degradation resistance (measured through Carbonyl Indices, CI), mechanical properties (tensile strength), thermal (Thermogravimetric Analysis—Differential Scanning Calorimetry, TGA-DSC), structure (Fourier Transform Infrared Spectroscopy, FT-IR), morphology (Scanning Electron Microscopy, SEM) and appearance (colorimetry and gloss). Key quantitative findings include a 35% reduction in tensile strength for raw PLA after 1000 h weathering exacerbated to 48% and 50% with 1% and 3% OBA incorporation, respectively. Degradation indices showed increased hydroxyl formation, with HI values ranging from 0.38 to 2.80 for PLA, while for biocomposites HI rose up to 5.85 for PLA with 3% OBA. Subsequently, a solid-state reaction was model-fitted from experimental data obtained by means of TGA analysis for determining the kinetic triplet (pre-exponential factor, the activation energy, and the reaction mechanism). Finally, the Acceleration Factor (AF), which combines the effects of radiation, temperature, and humidity to predict long-term material performance, is addressed analytically. Full article

This work optimizes the energetic performance of 2,4,6-trinitrotoluene (TNT) abatement in water using a sono-photo-Fenton-like (SPF) process coupled with nano zero-valent iron (nZVI). A response–surface methodology (RSM) with a five-level central composite design (CCD) was applied to concurrently minimize specific energy consumption (SEC) from ultrasound (US) and UV irradiation while maximizing TNT removal. The optimal conditions were US power 80 W for 2 min and UV power 10 W for 6 min, yielding 73.95% TNT removal with SEC = 101.19 kWh kg⁻¹ TNT removed. The analysis of variance (ANOVA) test revealed that US power had the greatest effect on removal efficiency, whereas UV and US exposure times predominantly influenced SEC. Relative to the other Fenton-like configurations examined, the optimized SPF achieved superior removal at lower SEC and enabled enhanced iron recovery compared with photo-Fenton process using Fe²⁺. When applied to actual “yellow” wastewater, the optimized SPF again outperformed the photo-Fenton process using Fe²⁺, reducing SEC from 380.77 to 252.60 kWh kg⁻¹ and increasing treatment efficiency. The high-power/short-duration US paired with a low-power/short-duration UV regime provides a favorable efficacy–energy trade-off and supports pilot-scale deployment. Full article

This study investigates the deterioration of the thermal and mechanical properties of geopolymer foam concrete (GFC) subjected to accelerated weathering through carbonation, salt fog, and UV radiation. GFC blocks were synthesized using metakaolin as the aluminosilicate precursor, activated with an alkaline solution consisting of 8 M NaOH and sodium silicate (Na₂SiO₃) at a NaOH/Na₂SiO₃ ratio of 0.51 wt.%. A 30% (v/v) H₂O₂ solution served as the foaming agent, and olive oil was used as the surfactant. Accelerated carbonation tests were conducted at 25 ± 3 °C and 40 ± 3 °C, under 60 ± 5% relative humidity and 5% CO₂, with carbonation depth, carbonation percentage, density, porosity, and thermal conductivity evaluated over a 7-day period. In parallel, specimens were exposed to salt fog and UV radiation for 12 weeks in accordance with ASTM B117-19 and ASTM G154-23, respectively. Compressive strength was monitored every week throughout the exposure period. Results show that carbonation temperature governs the type and kinetics of carbonate formation. The carbonation process, at 40 °C for 7 days, increased the density and reduced the porosity of GFC, resulting in a ~48% increase in thermal conductivity. Salt fog exposure led to severe mechanical degradation, with NaCl penetration reducing compressive strength by 69%. In contrast, UV radiation caused only minor deterioration, decreasing compressive strength by up to 7%, likely due to surface-level carbonation. Full article

Intrinsic aging and external stimuli such as UV exposure contribute to heightened MMP-1 expression, leading to collagen deterioration and weakening of the skin’s structural framework, hallmarks of aging tissue. Peucedanum japonicum, a plant consumed in East Asia, contains antioxidant and anti-inflammatory compounds, but its effects on skin aging remain unclear. This study profiled six major bioactive compounds in P. japonicum leaves and roots and evaluated their protective effects in TNF-α-stimulated human dermal fibroblasts (NHDFs). Phytochemical profiles were determined, and biological activity was evaluated by measuring intracellular ROS, MMP-1 secretion, and COL1A1 expression. Both leaf and root extracts exhibited antioxidant and anti-inflammatory activity, with leaves generally showing stronger effects. Among the six compounds, chlorogenic acid (1) demonstrated the most potent activity. It markedly decreased intracellular ROS, suppressed MMP-1 secretion, and enhanced COL1A1 expression in TNF-α-stimulated NHDFs, indicating protection against inflammation-induced collagen degradation. These findings suggest that P. japonicum, particularly its chlorogenic acid (1) content, may be a promising natural resource for anti-aging skincare and therapies targeting inflammation-associated skin damage. Full article

Microplastics (MPs) are a global concern due to their persistence and capacity to adsorb and transport pollutants. The Canary Islands, influenced by the Canary Current, are particularly vulnerable to MPs accumulation from remote sources. The European Union’s Watch List includes emerging contaminants that require monitoring to assess potential ecological risks, though limited data hinder definitive evaluations. This study conducted a monitoring campaign between December 2023 and September 2024 across eleven beaches on four eastern islands of the archipelago. The aim was to assess MPs pollution (particles between 1 and 5 mm) and the presence of 26 organic contaminants from the EU Watch List adsorbed onto MPs, evaluating seasonal variation and tourism influence. Results show that beaches facing north and east had significantly higher MPs levels—up to an order of magnitude greater (ranged from <10 to >500 items/m²)—due to strong wind exposure, confirming the role of the Canary Current in MPs transport. White/transparent fragments dominated (>50%) among MPs types. Eight Watch List compounds were identified, with UV filters—commonly found in sunscreens—being the most frequently detected, present at nearly all sampling sites. Octocrylene reached concentrations up to 17,811 ng/g in highly touristic beaches. These findings highlight the environmental pressure on insular coastal zones and the relevance of combining MPs monitoring with targeted contaminant analysis in regions affected by oceanic currents and tourism. Full article

Skin aging, driven by oxidative stress, UV exposure, inflammation, and extracellular matrix degradation, necessitates the discovery of safer, multi-target natural products. We established an integrated pipeline combining UHPLC–MS/MS metabolomics, computational methods (network pharmacology, molecular docking, and dynamics simulation), and in vitro bioassays to efficiently discover and mechanistically characterize anti-aging compounds from novel botanical sources. We applied this pipeline to identify and evaluate Tephroseris flammea, a previously unassessed plant. Metabolomic profiling identified 21 compounds, including flavonoids, phenylpropanoids, and pyrrolizidine alkaloids. These compounds were linked via network pharmacology to 226 skin-aging-related targets, primarily involving inflammation (via AKT1, RELA) and matrix degradation (via MAPK3). Molecular docking and 100 ns molecular dynamics simulations confirmed stable ligand-target interactions with favorable binding energies. Validating these in silico predictions, the T. flammea extract demonstrated significant antioxidant activity and effectively suppressed key inflammatory mediators (IL-6, TNF-α, COX-2) and MMP-1 levels in UVB-exposed fibroblasts, notably without significant cytotoxicity. Collectively, this study validates the utility of our pipeline to mechanistically characterize complex botanicals, revealing that T. flammea contains multifunctional compounds modulating critical inflammatory and matrix-regulatory cascades. This work validates our pipeline for identifying novel, mechanistically defined ingredients from complex botanical sources. Full article

Skin is constantly exposed to UV radiation. While topical sunscreens are the main preventative measure, oral photoprotective agents are emerging as promising systemic adjuncts, offering uniform, continuous protection. This study presents the results of two clinical trials designed to evaluate the efficacy of supplementation with a standardized coriander (Coriandrum sativum L.) seed oil (CSO) in mitigating UV-induced skin damage, in comparison with a placebo. The first trial investigated the effects of CSO supplementation on women with reactive skin, assessing UVA+B-induced skin erythema and tumor necrosis factor-alpha (TNF-α) release. The second trial included women of all skin types and, in addition to the outcomes mentioned above, examined UVA-induced lipoperoxidation. Measurements were taken before and after 56 days of supplementation. CSO supplementation led to a significant reduction in UV-induced skin erythema and associated TNF-α levels in both cohorts, with decreases of 11.8% and 24.1% in the reactive skin group and 18.1% and 18.7% in the cohort with all skin types, respectively. In women of all skin types, UV-induced skin lipoperoxidation was reduced by 31.9% at 4 h and by 69.9% at 24 h post-exposure. To the best of our knowledge, this is the first study reporting the photoprotective efficacy of CSO. This finding is attributed to CSO’s high petroselinic acid content and its known anti-inflammatory properties. Full article