Search Results (45,730)

Cod liver oil is a rich source of polyunsaturated fatty acids (PUFAs) but is highly susceptible to oxidative degradation, limiting its use in topical formulations. This study aimed to develop stable cod liver oil nanoemulsions for topical application and to evaluated the influence of surfactant ratio (lecithin/PEG-15 hydroxystearate: 2.5:1 and 1:1, w/w), emulsification method (ultrasonication or high-pressure homogenization), and vitamin E acetate supplementation on their physicochemical properties and oxidative stability. Eight nanoemulsions were characterized in terms of droplet size, polydispersity, ζ-potential, vitamin E acetate encapsulation efficiency, oxidative stability, film-forming capacity and cytocompatibility. Among the investigated formulations, F4 (2.5:1 lecithin/PEG-15 hydroxystearate, high-pressure homogenization, with vitamin E acetate) exhibited the most favorable characteristics, including a mean droplet size of 67.95 nm, ζ-potential of −63.12 mV and vitamin E acetate encapsulation efficiency of 32.59%. The formulation demonstrated good physicochemical stability under thermal, mechanical and photostability testing, improved oxidative stability, transient film-forming behavior with an initial occlusive effect, and no cytotoxicity toward human dermal fibroblasts. These findings indicate that nanoemulsion performance depends on the combined influence of formulation composition and processing conditions, with F4 representing a promising topical carrier for cod liver oil intended for interaction with the stratum corneum. Full article

In order to investigate possible ionospheric anomalies before a magnitude 7.6 earthquake (EQ) in the Japanese Noto Peninsula on 1 January 2024, we used oblique ionosonde data sounding at Wakkanai and Yamagawa with an assumed one-hop reflection point (ORP) only 169 km away from the EQ epicenter, which was not covered by vertical ionosonde observation. The NmF2 at ORP was analyzed. We found a long-lasting negative anomaly from the preceding day to the EQ occurrence, which was 3.37 standard deviations below the previous 30-day mean. We also found a positive anomaly 2 days before the EQ. In addition, we observed a new type of NmF2 anomaly around midday, which has not yet been reported in the literature. The midday NmF2 was anomalous for 10, 8 days, and a few hours before the EQ, implying possible pre-seismic modifications of the mesospheric meridional neutral wind. On the other hand, we also found NmF2 anomalies 3 and 4 days before a major aftershock on 9 January, revealing that the lithosphere–atmosphere–ionosphere coupling (LAIC) remained active, as seismic activity continued some days after the EQ mainshock. Since both positive and negative anomalies were observed before the EQ, pre-seismic atmospheric gravity wave (AGW) activity is the main agent driving LAIC processes. The present study not only reports pre-seismic anomalies before the 2024 Noto Peninsula EQ but also demonstrates the utility of oblique ionosondes on the ionospheric monitoring over Japan, especially for pre-seismic studies. Full article

Mitochondrial alterations, including mitochondrial DNA (mtDNA) loss and defects in maintenance pathways, have been recognized as an important driver for toxic effects of environmental pollutants. Therefore, exposure to nano-sized particles (1–100 nm in diameter; a new source of environmental pollution) may also result in these mitochondrial impairments; however, controversial results have been reported. Available studies collected from three electronic databases through July 2025 were pooled for a comprehensive assessment. Meta-analysis of 19 in vitro studies (69 datasets) showed exposure to nano-sized particles significantly reduced mtDNA content [standardized mean difference = −1.08; p-value = 0.001). The expression levels of mtDNA-encoded (ND1, COX1,2, CYTB, ATP6), mitochondrial biogenesis (SIRT1, PGC-1α, TFAM) and fusion genes (MFN1, MFN2, OPA1) were found to be significantly down-regulated, while fission genes DRP1 and FIS1 were up-regulated following nano-sized particle exposure after meta-analysis of corresponding in vitro and in vivo studies. Accordingly, mtDNA depletion and expression disruption in mtDNA-encoded and maintenance genes may represent important contributors to nano-sized particle exposure-induced diseases. Full article

The concentration of electric fields at the end region of stator bars in large generators can readily induce corona discharge. Under long-term operation, corona discharge may cause drift in the surface conductivity and nonlinear coefficient of anti-corona materials, thereby weakening their capability to homogenize the tangential electric field. In severe cases, this can lead to charring failure of the anti-corona material. To improve the electrical-parameter stability and surface morphological resistance to corona aging of silicon carbide (SiC)-based anti-corona materials under long-term corona exposure, epoxy-resin-based anti-corona materials were investigated in this study. Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) were first employed to analyze the effects of corona aging on the microstructure and chemical structure of the anti-corona layer, thereby revealing its failure mechanism. Subsequently, the evolution of surface conductivity, nonlinear coefficient, and surface morphology of bisphenol A epoxy resin (EP)- and hydrogenated bisphenol A epoxy resin (H-EP)-based anti-corona materials during 120 h of corona aging was comparatively investigated. On this basis, different mass fractions of organically modified montmorillonite (OMMT) were introduced into the H-EP-based anti-corona material for synergistic modification. The OMMT used in this study had a particle size of approximately 5 μm and an interlayer spacing of 2.6 nm, and its lamellar morphology and dispersion state in the epoxy matrix were characterized by cross-sectional SEM. Meanwhile, the trap-regulation mechanism of the OMMT-modified anti-corona materials was analyzed using isothermal surface potential decay (ISPD). The results show that erosion of the epoxy resin matrix by corona discharge is the primary cause of internal conductive-pathway disruption and anti-corona layer failure. Compared with the EP-based material, the H-EP-based material exhibited better conductivity and nonlinear stability during aging, although a certain degree of drift still occurred. The incorporation of an appropriate amount of OMMT further improved the corona resistance of the material. Among the investigated samples, the material containing 1 wt% OMMT showed the best performance, with its conductivity stabilized within the range of 10^−13–10⁻¹¹ S, the lowest variation rate of 104.76%, a relatively stable nonlinear coefficient, and slight surface damage. The ISPD results indicate that the interfaces introduced by OMMT increase the deep-trap density and suppress carrier migration, thereby stabilizing the conductive network. Overall, the synergistic effect of the H-EP matrix and 1 wt% OMMT can effectively enhance the corona resistance of SiC-based anti-corona materials. Full article

Hydroxyapatite (HAp) is a widely used bioceramic in bone tissue engineering due to its biocompatibility and osteoinductive capacity; however, sustainable low-cost synthesis routes remain a challenge. This study evaluated HAp-polysaccharide composite synthesis from nejayote, the alkaline wastewater of maize nixtamalization, via chemical precipitation with (NH₄)₃PO₄ under controlled and uncontrolled pH, followed by calcination at 550 °C for 2 or 4 h. Controlled pH synthesis yielded higher solid recovery (89.8% vs. 76.4%), better calcium removal (99.8% vs. 87.4%), and smaller particle sizes (423.6 nm vs. 715.0 nm). XRD and FTIR confirmed HAp formation in both conditions, with crystallinity increasing upon calcination. Monomeric composition analysis revealed co-precipitation of amylose and arabinoxylan-derived polysaccharides in uncalcined samples, progressively eliminated by thermal treatment. Cell viability assays with human fetal osteoblasts (hFOB 1.19) confirmed non-cytotoxicity at all concentrations tested (10–633 μg/mL). Uncalcined composites synthesized without pH control achieved 126% cell viability at 633 μg/mL, surpassing pH-controlled and calcined counterparts (90–100%), suggesting active promotion of osteoblast proliferation, further supported by fluorescence imaging. These results establish nejayote as a viable dual source of calcium and polysaccharides for sustainable HAp composite synthesis with biomedical potential. Full article

This work reports the development of innovative enzyme–titanium nanobiohybrids synthesized via a protein-assisted approach to obtain efficient and sustainable photocatalysts for environmental remediation. By addressing the limitations of conventional TiO₂ nanoparticle synthesis, this strategy enables controlled material properties under milder, potentially scalable conditions for enhanced ROS-driven degradation of persistent dye pollutants. This work employs a bio-assisted synthesis approach using β-glucosidase as a protein scaffold, TiCl₄ as the titanium precursor, and H₂O₂ in bicarbonate buffer at room temperature, eliminating the need for harsh conditions and high temperatures. The biological moiety guides the nanoparticle formation, controlling size and morphology while preventing aggregation, all performed under mild conditions. X-ray diffraction determined that the Ti hybrid was composed of TiO₂ brookite species. TEM analyses demonstrated the formation of well-dispersed nanostructures of around 700 nm. The resulting nanobiohybrids showed excellent photocatalytic activity, achieving >99% Rhodamine B degradation under UV light in only 1 h compared to visible light. The catalyst was capable of degrading Rhodamine B at a concentration approximately 36 times above the recommended threshold for water. Furthermore, a preactivation of the catalyst by direct exposition of it to UV-395 nm light greatly enhanced the efficiency in the photocatalytic process, being inactive in visible light. The Ti–enzyme hybrid showed excellent recyclability over five consecutive cycles and retained good activity after storage, demonstrating its stability. This study introduces a sustainable and efficient route for synthesizing Ti-based nanobiohybrids, providing a promising strategy for advanced photocatalytic applications in water treatment and environmental remediation. Full article

CoCrNiTiAl_x high-entropy alloy films with varied Al contents were fabricated on 42CrMo steel substrates via magnetron sputtering. By adjusting the sputtering power of the Al target, an investigation was systematically carried out to explore the effect of different Al contents on the microstructural evolution, mechanical properties, and corrosion resistance of the film, with the underlying synergistic mechanism governing these properties being elucidated. With increasing Al content, the film microstructure gradually transforms from an amorphous phase at low Al contents to a nanocrystalline–amorphous composite structure, until it is converted into the BCC phase, and the film’s crystallinity exhibits a trend of first increasing and then decreasing. In terms of mechanical properties, the film hardness is significantly enhanced from 7.6 ± 1.3 GPa to 18.9 ± 1.1 GPa with increasing Al content, while the toughness gradually declines. Wear tests show that the film wear rate first decreases and then increases with rising Al content, reaching a minimum of 2.06 × 10⁻⁵ mm³/N·m. The superior protective state, characterized by a corrosion potential reaching −361.2 mV and corrosion current density dropping to 1.12 μA/cm², arises from the generation of an integrated, consistently structured composite passivation barrier in 3.5 wt.% solution. This study confirms that appropriate Al doping can synergistically optimize the microstructure, mechanical properties, and corrosion resistance of CoCrNiTiAl_x films, providing experimental and theoretical support for the compositional design and engineering applications of high-performance high-entropy alloy protective films. Full article

The oil-immersed environment within power transformers is characterized by high temperatures, strong electric fields, and severe electromagnetic interference, posing significant challenges for simultaneous multi-parameter monitoring. Conventional electrical sensors are susceptible to electromagnetic interference, whereas typical integrated fiber Bragg grating (FBG) sensors exhibit cross-sensitivity and reliability issues under such harsh operating conditions. To address these challenges, this paper proposes an integrated FBG-based sensor. Through specialized material and structural design, each sensing element is engineered to respond predominantly to its target parameter at the physical level. This approach effectively mitigates cross-sensitivity, enabling high-precision simultaneous measurement of oil temperature, pressure, and moisture content. Under simulated transformer oil conditions, the sensor achieved a temperature sensitivity of 17.1 pm/°C, a pressure sensitivity of approximately 4 nm/MPa, and a moisture sensitivity of 7.775 × 10⁻⁴ nm/%RS (equivalent to 6.37 × 10⁻⁴ nm/ppm at 40 °C). The results also confirmed excellent linearity, repeatability, and resistance to cross-sensitivity. These findings demonstrate that the proposed integrated FBG sensor can achieve stable multi-parameter measurement and effective decoupling under the tested transformer-oil conditions, indicating its potential for engineering application in transformer online monitoring. Full article

We present in this paper a low-power impulse-radio ultra-wideband (IR-UWB) transmitter architecture for neural implants. It features a duty-cycled phase-locked loop (PLL) and a co-designed compact fractal antenna. To suppress the carrier frequency drift inherent in open-loop ring oscillators while maintaining ultra-low power consumption, a hybrid PLL-oscillator upconversion scheme integrated with a switch-controlled voltage-holding module is proposed. Operating at a 10% duty cycle, the PLL consumes merely 90 $\mu$W and achieves a locking frequency of 4.25 GHz with a peak-to-peak jitter of 2.14 ps. Furthermore, to eliminate the bulky output matching network, an 8 mm × 10 mm coplanar-waveguide-fed fractal antenna is co-designed to present the conjugate impedance required by the power amplifier output, significantly advancing the miniaturization and energy efficiency of the neural implant. The complete transmitter was fabricated in TSMC 40 nm CMOS, with a supply voltage of 1.0 V, and in vitro wireless experiments through 18 mm of porcine tissue validated the design with a total power consumption of 0.58 mW. Full article

Accurate monitoring of substrate moisture content and electrical conductivity (EC) is essential for irrigation and nutrient management in soilless strawberry cultivation. However, conventional sensor-based approaches are limited in spatial coverage. This study developed a multimodal prediction framework integrating canopy multispectral imaging (713–920 nm) with greenhouse environmental and irrigation time-series data to estimate substrate state non-destructively. Four spectral preprocessing schemes were evaluated, and the first derivative of digital number values was adopted as the primary preprocessing condition. Five regression models, including a proposed spectrum-query cross-attention long short-term memory network (SpecAtten-LSTM), were compared across six spectral input configurations and five non-spectral baselines. Substrate EC was predicted accurately from either modality alone. Extreme gradient boosting reached R² = 0.9710, and the environment-only baselines achieved comparable performance, suggesting that either modality contained sufficient information for EC prediction. For substrate moisture content, the highest performance was obtained when spectral and environmental information were combined. SpecAtten-LSTM achieved the highest accuracy (R² = 0.7463) under the full multimodal configuration, and an ablation analysis confirmed that its cross-attention and fusion modules drove this gain. Permutation importance identified relative humidity as the dominant environmental variable for both targets. The results indicate that canopy-level observations can be used to estimate root-zone substrate conditions and that spectral information provides additional value primarily for substrate moisture content prediction. Full article

Predicting canopy traits non-destructively is important for understanding crop growth and improving phenotyping efficiency. Hyperspectral reflectance provides detailed spectral information, but the role of band selection in regression-based trait prediction at the canopy scale remains unclear. In this study, we evaluated the effects of different band-selection algorithms on the prediction accuracy of aboveground biomass (AGB), leaf area index (LAI), and canopy cover (CC) in soybeans using canopy hyperspectral reflectance in the visible to near-infrared (VNIR) range from 501 to 801 nm. The dataset included multiple sites, years, cultivars, and irrigation treatments. We compared a full-band partial least squares regression (PLS) model with three band-selection methods (PLS-Variable Importance in Projection (VIP), Bootstrapped least absolute shrinkage and selection operator (LASSO) (BoLASSO), and an ensemble approach). Model performance was assessed using Kennard–Stone validation and leave-one-year-out cross-validation. The results showed that the effectiveness of band selection depended on the target trait. Full-band PLS performed well for AGB under Kennard–Stone validation, whereas BoLASSO achieved comparable accuracy to PLS for LAI and CC using a reduced number of selected bands. Leave-one-year-out cross-validation showed that year-to-year transferability was more difficult for AGB than for LAI and CC. The selected wavelengths were located mainly in the visible, red-edge, and near-infrared regions. These results indicate that band-selection strategies should be tailored to the target trait and that selected VNIR bands can provide candidate spectral regions for simplified sensing of soybean canopy traits. Full article

Understanding turbidity in coastal systems is essential to ensure the sustainable management of these ecosystems, which are increasingly under pressure from natural factors and human activities. Thus, this study aims to develop a local Sentinel-2-based turbidity model for the Aveiro lagoon (Portugal) by combining Sentinel-2 records with in situ measurements. A field campaign synchronized with a Sentinel-2 overpass was conducted across the lagoon channels on 28 May 2025, to capture spatial variability by measuring near-surface turbidity and Secchi depth, for correspondence with the spectral records of satellite. Remote Sensing Reflectance (Rrs) and turbidity were derived using various algorithms integrated within the ACOLITE software (v20250114.0). Additionally, new turbidity models were developed and empirically adjusted based on the Rrs data, with their performance quantified through the coefficient of determination (R²) and Root Mean Square Error (RMSE). The results showed that the existing algorithms are not directly suitable for the Aveiro lagoon, as they underestimate the highest turbidity values. The ratio between 665 and 560 nm bands (RG_ratio) proved to be the most suitable spectral index, performing best in estimating turbidity (R² = 0.822 and RMSE = 1.77 NTU). This study highlights the importance of locally calibrated models over standard ACOLITE algorithms for turbidity retrieval in shallow coastal lagoons, while emphasizing that the proposed model was calibrated for the tidal, wind, and river discharge conditions sampled during the campaign and has not yet been independently validated. Full article

Weekend cyclists are individuals who engage in vigorous physical activity only on weekends, as opposed to those who exercise regularly during the week. Research suggests that concentrating physical training on one or two days may benefit heart health and metabolism, similar to exercising regularly. However, it remains unclear whether weekend cyclists exhibit similar adaptations in metabolic, performance, and muscle oxygenation markers. The aim of this study is to compare cardiorespiratory fitness, body composition, cardiometabolic risk markers, muscle strength, and muscle oxygenation between cyclists who concentrated training on weekends and cyclists who distributed training across three or more days per week. In this study, we used an analytical, observational, non-experimental design that recruited 28 cyclists, divided into weekend cyclists (n = 14) and regular cyclists (n = 14). Body composition, blood tests, lower body strength, aerobic capacity, and muscle oxygen saturation were assessed. Results: Weekend cyclists exhibited lower VO₂max (36.7 ± 3.9 vs. 48.9 ± 6.3 mL·kg⁻¹·min⁻¹), lower knee extension strength (3.16 ± 0.57 vs. 4.42 ± 0.83 Nm·kg⁻¹), and reduced ΔSmO₂ responses during exercise compared with regular cyclists (all p < 0.05). In addition, weekend cyclists presented higher body fat percentage (25.9 ± 3.8 vs. 17.2 ± 4.2%), greater waist circumference (90.5 ± 4.3 vs. 83.6 ± 5.1 cm), and lower HDL cholesterol levels (54.2 ± 8.4 vs. 64.1 ± 11.0 mg/dL). In conclusion, weekend cyclists have lower cardiorespiratory fitness, muscular strength, and reduced ΔSmO₂ responses during incremental exercise, along with higher levels of visceral fat and triglycerides, compared to those who train three or more days a week. The distribution and frequency of training within their workout plans were associated with differences in cardiorespiratory fitness and cardiometabolic markers. Full article

Ni-W-Y₂O₃ composite coatings were electrodeposited from a sulfate citrate electrolyte incorporating Y₂O₃ particles of three different sizes: 50 nm, 1 μm, and 2 μm. This study systematically investigates the impact of Y₂O₃ particle size on the microstructure, microhardness, corrosion resistance, and wear resistance of the composite coatings. The incorporation of Y₂O₃ particles leads to notable grain refinement, with the crystallite size decreasing from 31.8 nm for the pure Ni W coating to 17.3 nm, 19.0 nm, and 20.1 nm for the C-50 nm, C-1 μm, and C-2 μm coatings, respectively. Correspondingly, the microhardness increases from 540.2 HV for the unreinforced coating to 732.5 HV, 641.0 HV, and 629.5 HV for the C-50 nm, C-1 μm, and C-2 μm coatings, respectively. In terms of corrosion resistance, the C-50 nm coating exhibits the best performance in both acidic and neutral media, with the lowest corrosion current density of 3.72 μA/cm² in 10 wt.% H₂SO₄ and 3.53 μA/cm² in 3.5 wt.% NaCl. In contrast, micron-sized particles show limited improvement in acidic media and even degrade the corrosion resistance in neutral NaCl solution, where the corrosion current density increases to 7.68 μA/cm² and 7.74 μA/cm² for the C-1 μm and C-2 μm coatings, respectively. The wear resistance of the composite coatings is significantly enhanced by the incorporation of Y₂O₃ particles, with the wear rate decreasing from 17.75 × 10⁻⁶ mm³ N⁻¹ m⁻¹ for the pure Ni-W coating to 5.65 × 10⁻⁶ mm³ N⁻¹ m⁻¹ for the C-50 nm coating. The presence of Y₂O₃ particles transitions the wear mechanism from predominantly adhesive wear to a combination of adhesive and abrasive wear. These results demonstrate that the particle size of Y₂O₃ plays a critical role in determining the microstructure and overall performance of Ni-W-Y₂O₃ composite coatings, with nano-sized particles offering the most significant improvements. Full article

How do microorganisms in litter and soil affect litter decomposition in a temperate forest? Here, we conducted an 18-month laboratory experiment to assess the decomposition of pure Robinia pseudoacacia, pure Platycladus orientalis, and mixed R. pseudoacacia–P. orientalis litters under four treatments, namely “no microbe” (NM), “litter microbes” (LM), “soil microbes” (SM), and “litter and soil microbes” (LM + SM). Results demonstrated that, compared with SM, LM significantly enhanced the litter weight-loss rate and elevated the potential activities of lignocellulolytic enzymes at 180 days, and this was accompanied by lower cellulose and hemicellulose contents. Structural equation modeling indicated that microorganisms may directly or indirectly influence weight mass loss, partly by regulating these potential enzyme activities that are associated with changes in the litter organic matter composition. Across three forest stands, microbial treatments significantly affected litter decomposition. The standardized direct path coefficients linking microorganisms to the litter-mass-loss rate from highest to lowest were LM + SM, LM, and SM, indicating a synergistic effect between LM and SM that promotes decomposition through coordination. Taxonomically, most bacterial genera differed significantly among microbial treatments, whereas most fungal genera did not. Notably, the standardized direct path coefficient linking bacteria to litter mass loss was larger than that for fungi in both the SM and LM + SM groups. Additionally, field decomposition was faster than in the laboratory, with distinct microbial communities, verifying the environmental modulation of decomposers and the home-field advantage. This study clarifies microbial mechanisms underlying litter decomposition and provides a theoretical basis for forest ecosystem stability and sustainable management. Full article