Search Results (369)

Background and purpose: Vulvovaginal candidiasis (VVC), caused by Candida albicans (C. albicans), is exacerbated by oxidative stress and uncontrolled inflammation. Pathogens like C. albicans generate reactive oxygen species (ROS) to enhance virulence, while host immune responses further amplify oxidative damage. This study investigates the antioxidant and antifungal properties of Hyssopus cuspidatus Boriss volatile extract (SXC), a traditional Uyghur medicinal herb, against fluconazole-resistant VVC. We hypothesize that SXC’s bioactive volatiles counteract pathogen-induced oxidative stress while inhibiting fungal growth and inflammation. Methods: GC-MS identified SXC’s major bioactive components, while broth microdilution assays determined minimum inhibitory concentrations (MICs) against bacterial/fungal pathogens, and synergistic interactions with amphotericin B (AmB) or fluconazole (FLC) were assessed via time–kill kinetics. Anti-biofilm activity was quantified using crystal violet/XTT assays, and in vitro studies evaluated SXC’s effects on C. albicans-induced cytotoxicity (LDH release in A431 cells) and inflammatory responses (cytokine production in LPS-stimulated RAW264.7 macrophages). A murine VVC model, employing estrogen-mediated pathogenesis and intravaginal C. albicans challenge, confirmed SXC’s in vivo effects. Immune modulation was assessed using ELISA and RT-qPCR targeting inflammatory and antioxidative stress mediators, while UPLC-MS was employed to profile metabolic perturbations in C. albicans. Results: Gas chromatography-mass spectrometry identified 10 key volatile components contributing to SXC’s activity. SXC exhibited broad-spectrum antimicrobial activity with MIC values ranging from 0.125–16 μL/mL against bacterial and fungal pathogens, including fluconazole-resistant Candida strains. Time–kill assays revealed that combinations of AmB-SXC and FLC-SXC achieved sustained synergistic bactericidal activity across all tested strains. Mechanistic studies revealed SXC’s dual antifungal actions: inhibition of C. albicans hyphal development and biofilm formation through downregulation of the Ras1-cAMP-Efg1 signaling pathway, and attenuation of riboflavin-mediated energy metabolism crucial for fungal proliferation. In the VVC model, SXC reduced vaginal fungal burden, alleviated clinical symptoms, and preserved vaginal epithelial integrity. Mechanistically, SXC modulated host immune responses by suppressing oxidative stress and pyroptosis through TLR4/NF-κB/NLRP3 pathway inhibition, evidenced by reduced caspase-1 activation and decreased pro-inflammatory cytokines (IL-1β, IL-6, TNF-α). Conclusions: SXC shows promise as a broad-spectrum natural antimicrobial against fungal pathogens. It inhibited C. albicans hyphal growth, adhesion, biofilm formation, and invasion in vitro, while reducing oxidative and preserving vaginal mucosal integrity in vivo. By disrupting fungal metabolic pathways and modulating host immune responses, SXC offers a novel approach to treating recurrent, drug-resistant VVC. Full article

Background/Objectives: Recent advancements in innovative drug delivery nanosystems have significantly impacted wound healing, particularly through the incorporation of natural products. This study aimed to develop and characterize a Phlomis crinita extract-loaded nanostructured formulation (PCE-NF) as a topical therapy for skin wounds. Methods: This study involved the incorporation of P. crinita extract in a nanoemulsion by the high-energy emulsification method. This formulation was subjected to physicochemical and biopharmaceutical characterization, and a physical stability study over 30 days. Biocompatibility, tolerability, and irritant effects were assessed, while the wound healing potential was evaluated using in vitro skin models of fibroblasts and keratinocytes. Results: PCE-NF showed a homogeneous appearance with nanometric-sized spherical droplets of 212.27 nm and Newtonian behavior. This formulation showed a sustained release of its majority component (luteonin 7-(6″-acetylglucoside)), which followed a hyperbolic kinetic while showing high permeation, through healthy human skin, with 22.01 µg after 27 h. There were no cytotoxic effects of PCE-NF with improvements in skin barrier function and hydration levels. The wound healing potential of PCE-NF at 3.125 µg/mL was evidenced by enhanced cell migration and accelerated wound closure in 3T3-L1 and HaCaT cells, with values of 94.24 and 92.41%, respectively. Conclusions: These results suggest that this formulation could be used as an effective wound healing treatment. Full article

Co-combustion is regarded as an effective means for high-efficiency utilization of low-quality fuels. However, low-quality fuel has problems such as low energy density and high water content. The fuel quality and blending performance can be further optimized by the pretreatment of low-quality fuel, for example, calorific value, hydrophobicity, and NO conversion rate. Based on the idea of co-upgradation, this study systematically investigates the effects of integrated upgrading on fuel quality and hydrophobicity under different conditions. In this study, lignite and wheat straw were selected as research objects. The co-upgrading experiments of wheat straw and lignite were conducted at reaction temperatures of 170 °C, 220 °C, and 270 °C in flue gas and air atmospheres with biomass blending ratios of 0%, 25%, 50%, 75%, and 100%. SEM (scanning electron microscopy) and nitrogen (N₂) adsorption analyses showed that under low-temperature and low-oxygen conditions, organic components from biomass pyrolysis migrated in situ to cover the surface of lignite, resulting in a gradual smoothing of the fuel surface and a decrease in the specific surface area. Meanwhile, water reabsorption experiments and contact angle measurements showed that the equilibrium water holding capacity and water absorption capacity of the lifted fuels was weakened, and hydrophobicity was enhanced. Combustion kinetic parameters and pollutant release characteristics were investigated by thermogravimetric analysis (TGA) and isothermal combustion tests. It was found that co-upgradation could effectively reduce the reaction activation energy and NO conversion rate. Characterized by Raman spectroscopy (Raman) and X-ray photoelectron spectroscopy (XPS), in situ migration of organic components affected combustion reactivity by modulating changes in N-containing product precursors. The results showed that the extracted fuel with a 75% biomass blending ratio in the flue gas atmosphere exhibited the best overall performance at 220 °C, with optimal calorific value, combustion reactivity, and hydrophobicity. These findings may provide important theoretical foundations and practical guidance for the optimization of industrial-scale upgrading processes of low-quality fuels. Full article

Hydrogen is emerging as a key energy vector for the transition toward renewable and sustainable energy sources. However, its safe and efficient storage remains a significant technical challenge in terms of cost, safety, and performance. In this study, we aimed to address the kinetic limitations of Mg by synthesizing catalyzed Mg@Ni systems using commercially available micrometric magnesium particles (~26 µm), which were decorated via electroless nickel plating under both aqueous and anhydrous conditions. Morphological and compositional characterization was carried out using SEM, EDS, and XRD. The resulting materials were evaluated through Temperature-Programmed Desorption (TPD), DSC, and isothermal hydrogen absorption/desorption kinetics. Reversibility over multiple absorption–desorption cycles was also investigated. The synthesized Mg@NiB system shows a reduction of 37 °C in the hydrogen release activation temperature at atmospheric pressure and a decrease of 167.3 °C under high vacuum conditions (4.5 × 10⁻⁷ MPa), in addition to a reversible hydrogen absorption/desorption capacity of 3.5 ± 0.09 wt.%. Additionally, the apparent activation energy for hydrogen desorption was lower (161.7 ± 21.7 kJ/mol) than that of hydrogenated commercial pure magnesium and was comparable to that of milling MgH₂ systems. This research is expected to contribute to the development of efficient and low-cost processing routes for large-scale Mg catalysis. Full article

The safe exploitation of marine natural gas hydrates, a promising cleaner energy resource, is hindered by reservoir instability during drilling. The inherent temperature–pressure sensitivity and cementation of hydrate-bearing sediments leads to severe operational risks, including borehole collapse, gas invasion, and even blowouts. This review synthesizes the complex instability mechanisms and evaluates the state of the art in inhibitive, wellbore-stabilizing drilling fluids. The analysis first deconstructs the multiphysics-coupled failure process, where drilling-induced disturbances trigger a cascade of thermodynamic decomposition, kinetic-driven gas release, and geomechanical strength degradation. Subsequently, current drilling fluid strategies are critically assessed. This includes evaluating the limitations of conventional thermodynamic inhibitors (salts, alcohols, and amines) and the advancing role of kinetic inhibitors and anti-agglomerants. Innovations in wellbore reinforcement using nanomaterials and functional polymers to counteract mechanical failure are also highlighted. Finally, a forward-looking perspective is proposed, emphasizing the need for multiscale predictive models that bridge molecular interactions with macroscopic behavior. Future research should prioritize the development of “smart”, multifunctional, and green drilling fluid materials, integrated with real-time monitoring and control systems. This integrated approach is essential for unlocking the potential of marine gas hydrates safely and efficiently. Full article

This study addresses the low reactivity and poor toughness of diabase tailings (DT), a high-silica industrial byproduct, which restricts their large-scale application in geopolymer binders. To overcome these limitations, a dual-regulation strategy integrating stepwise low-temperature thermal activation (100, 200, and 300 °C) with standard curing (20 ± 2 °C, 95% RH) was developed. This approach aimed to enhance mineral dissolution kinetics and facilitate the formation of a dense, interconnected gel network. XRD, FTIR, and SEM analyses revealed significant decomposition of amphibole, pyroxene, and olivine, accompanied by increased release of reactive Si and Al species, leading to the formation of a compact N–A–S–H/C–A–S–H gel structure. Under optimized conditions (Si/Al = 2.6; activator modulus = 1.2), the geopolymer achieved a 7-day compressive strength of 42.3 ± 1.8 MPa, a flexural strength of 12.76 ± 1.6 MPa, and a flexural-to-compressive strength ratio of 0.308, demonstrating significant improvements in toughness compared with conventional binders. This green, energy-efficient strategy not only reduces energy consumption and CO₂ emissions but also provides a technically feasible pathway for the high-value reuse of silicate-rich mining wastes, contributing to the development of sustainable construction materials with enhanced mechanical performance. Full article

This study investigates the adsorption behavior of 4-methylbenzylidene camphor (4-MBC), a persistent ultraviolet filter, onto microplastic fibers (MPFs) released from domestic textiles, under environmentally relevant conditions. Two types of MPFs were used: MPF A, a heterogeneous blend of synthetic and natural fibers, and MPF B, a uniform polyester source. Adsorption experiments were conducted in municipal wastewater, Danube River surface water, and laundry effluent. Kinetic data best fit the pseudo-second-order model (R² > 0.95), and the Elovich model indicated chemisorption involving heterogeneous binding sites. MPF A exhibited superior adsorption capacities (qₑ = 85.4–90.1 µg/g) compared to MPF B (58.8–66.8 µg/g). Langmuir isotherms yielded maximum adsorption capacities of 204.9 µg/g for MPF A and 116.7 µg/g for MPF B (R² = 0.929–0.977), while D–R isotherm energies (12.0–21.7 kJ/mol) confirmed specific interactions, such as π–π stacking and hydrogen bonding. Adsorption efficiency was highest in municipal wastewater (total organic carbon—TOC = 13.12 mg/L, electrical conductivity—EC = 1152 µS/cm), followed by laundry and surface waters. These findings emphasize the critical role of polymer composition and matrix complexity in pollutant transport, suggesting MPFs are effective transporters of hydrophobic micropollutants in aquatic systems. Full article

Thermogravimetric analysis (TGA) is a key technique for evaluating the kinetics and thermodynamics of thermal degradation, providing essential data for material assessment and system design. When coupled with Fourier-transform infrared (FT-IR) spectroscopy or mass spectroscopy (MS), it enables the identification of evolved gases and correlates mass loss with specific chemical species, offering detailed insight into decomposition mechanisms. In this study, TGA was coupled with FT-IR and MS to investigate the thermal degradation behavior of Bakelite, with the aim of evaluating its kinetic and thermodynamic parameters under non-isothermal conditions, identifying evolved volatile compounds, and elucidating the degradation process. The results showed that higher heating rates led to increased decomposition temperatures and broader dTG peaks due to thermal lag effects. The degradation proceeded in multiple stages between 220 °C and 860 °C, ultimately yielding a carbonaceous residue. The activation energy increased with conversion, particularly beyond 0.5, indicating a greater energy requirement as degradation progressed. Peak values at conversion degrees of 0.8–0.9 suggested enhanced thermal stability or changes in the dominant reaction mechanism. Detailed kinetic analysis revealed complex decomposition pathways with variable activation energies and a pronounced kinetic compensation effect. Thermodynamic analysis confirmed the endothermic nature of the process, with increasing energy demand and non-spontaneous degradation of the resulting char. TGA/FT-IR and TGA/MS analyses identified the release of several compounds, including CO₂, water, formaldehyde, and phenolic derivatives, at distinct stages. This comprehensive understanding of Bakelite’s thermal behavior supports its optimization for high-temperature applications, enhances material reliability and safety, and contributes to sustainable processing and recycling strategies. Full article

Excessive phosphate from agriculture and industry has led to widespread eutrophication, posing a serious environmental threat. To address this issue, metal-modified biochars have emerged as promising adsorbents due to their high affinity for phosphate ions. This study investigates the application of two magnesium-modified biochar hydrogels denoted as magnesium–bamboo biochar hydrogel (Mg-BBH) and magnesium–pulp biochar hydrogel (Mg-PBH) for phosphate recovery from aqueous solutions, with an additional aim as slow-release fertilizers. The adsorbents were synthesized by impregnating Mg-modified biochars into sodium-alginate-based hydrogel. The influence of initial phosphate concentration, contact time, and temperature were investigated to determine optimal adsorption conditions. Both adsorbents exhibited excellent adsorption performance, with maximum capacities of 309.96 mg PO₄/g (Mg-BBH) and 234.69 mg PO₄/g (Mg-PBH). Moreover, the adsorption performance of the adsorbents was greatly influenced by the magnesium content. The adsorption process followed the Temkin isotherm and pseudo-second-order kinetics, suggesting that the adsorption energy decreases proportionally with surface coverage and the phosphate uptake was governed by chemisorption. Thermodynamic study confirmed the process was spontaneous and endothermic at 40 °C. A slow-release study further demonstrated a great release of phosphate in soil over time. These findings highlight the dual functionality of Mg-BBH and Mg-PBH as effective materials for both phosphate recovery and controlled nutrient delivery, contributing to sustainable phosphate management. Full article

Petroleum oily sludge (OLS), a hazardous by-product of the petroleum industry, and high-alkali lignite (HAL), an underutilized low-rank coal, pose significant challenges to sustainable waste management and resource efficiency. This study systematically investigated the combustion behavior, reaction pathways, and gaseous-pollutant-release mechanisms across varying blend ratios, utilizing integrated thermogravimetric-mass spectrometry analysis (TG-MS), interaction analysis, and kinetic modeling. The key findings reveal that co-combustion significantly enhances the combustion performance compared to individual fuels. This is evidenced by reduced ignition and burnout temperatures, as well as an improved comprehensive combustion index. Notably, an interaction analysis revealed coexisting synergistic and antagonistic effects, with the synergistic effect peaking at a blending ratio of 50% OLS due to the complementary properties of the fuels. The activation energy was found to be at its minimum value of 32.5 kJ/mol at this ratio, indicating lower reaction barriers. Regarding gas emissions, co-combustion at a 50% OLS blending ratio reduces incomplete combustion products while increasing CO₂, indicating a more complete reaction. Crucially, sulfur-containing pollutants (SO₂, H₂S) are suppressed, whereas nitrogen-containing emissions (NH₃, NO₂) increase but remain controllable. This study provides novel insights into the synergistic mechanisms between OLS and HAL during co-combustion, offering foundational insights for the optimization of OLS-HAL combustion systems toward efficient energy recovery and sustainable industrial waste management. Full article

Driven by stringent emission regulations, advanced combustion modes utilizing turbulent jet ignition technology are pivotal for enhancing the performance of marine low-speed natural gas dual-fuel engines. This review focuses on three novel combustion modes, yielding key conclusions: (1) Compared to the conventional DJCDC mode, the TJCDC mode exhibits a significantly higher swirl ratio and turbulence kinetic energy in the main chamber during initial combustion. This promotes natural gas jet development and combustion acceleration, leading to shorter ignition delay, reduced combustion duration, and a combustion center (CA50) positioned closer to the Top Dead Center (TDC), alongside higher peak cylinder pressure and a faster early heat release rate. Energetically, while TJCDC incurs higher heat transfer losses, it benefits from lower exhaust energy and irreversible exergy loss, indicating greater potential for useful work extraction, albeit with slightly higher indicated specific NOx emissions. (2) In the high-compression ratio TJCPC mode, the Liquid Pressurized Natural Gas (LPNG) injection parameters critically impact performance. Delaying the start of injection (SOI) or extending the injection duration degrades premixing uniformity and increases unburned methane (CH₄) slip, with the duration effects showing a load dependency. Optimizing both the injection timing and duration is, therefore, essential for emission control. (3) Increasing the excess air ratio delays the combustion phasing in TJCPC (longer ignition delay, extended combustion duration, and retarded CA50). However, this shift positions the heat release more optimally relative to the TDC, resulting in significantly improved indicated thermal efficiency. This work provides a theoretical foundation for optimizing high-efficiency, low-emission combustion strategies in marine dual-fuel engines. Full article

The insulation layer of flame-retardant cables plays a critical role in mitigating fire hazards by influencing toxic gas emissions and the accuracy of fire modeling. This study systematically explores the pyrolysis kinetics and volatile gas evolution of flame-retardant polyvinyl chloride (PVC) and polyethylene (PE) insulation materials using advanced TG-FTIR-GC/MS techniques. Distinct pyrolysis stages were identified through thermogravimetric analysis (TGA) at heating rates of 10–40 K/min, while the KAS model-free method and Málek fitting function quantified activation energies and reaction mechanisms. Results revealed that flame-retardant PVC undergoes two major stages: (1) dehydrochlorination, characterized by the rapid release of HCl and low activation energy, and (2) main-chain scission, producing aromatic compounds that contribute to fire toxicity. In contrast, flame-retardant PE demonstrates a more stable pyrolysis process dominated by random chain scission and the formation of a dense char layer, significantly enhancing its flame-retardant performance. FTIR and GC/MS analyses further highlighted distinct gas evolution behaviors: PVC primarily generates HCl and aromatic hydrocarbons, whereas PE releases olefins and alkanes with significantly lower toxicity. Additionally, the application of a classification and regression tree (CART) model accurately predicted mass loss behavior under various heating rates, achieving exceptional fitting accuracy (R² > 0.98). This study provides critical insights into the pyrolysis mechanisms of flame-retardant cable insulation and offers a robust data framework for optimizing fire modeling and improving material design. Full article

This study investigated the impact of increased extraplatelet content on the tissue regenerative capacity of platelet-rich plasma (PRP)-derived fibrin scaffolds. Comparative analyses were performed between a “balanced protein-concentrate plasma” (BPCP) and a standard PRP (sPRP), focusing on platelet and fibrinogen content, scaffold microstructure, and functional performance. Growth factor (GF) release kinetics from the scaffolds were quantified via ELISA over 10 days, while scaffold biomechanics were evaluated through rheological testing, indentation, energy dissipation, adhesion, and assessments of coagulation dynamics, biodegradation, swelling, and retraction. Microstructural analysis was conducted using scanning electron microscopy (SEM), with fiber diameter and porosity measurements. The results demonstrated that BPCP scaffolds released significantly higher amounts of GFs and total protein, especially beyond 24 h (* p < 0.05). Despite a delayed coagulation process (** p < 0.01), BPCP scaffolds exhibited superior structural integrity and cushioning behavior (* p < 0.05). SEM revealed thicker fibers in BPCP scaffolds (**** p < 0.0001), while adhesion and biodegradation remained unaffected. Notably, BPCP scaffolds showed reduced retraction after 24 h and maintained their shape stability over two weeks without significant swelling. These findings indicate that enhancing the extraplatelet content in PRP formulations can optimize fibrin scaffold performance. Further preclinical and clinical studies are warranted to evaluate the therapeutic efficacy of BPCP-derived scaffolds in regenerative medicine. Full article

The development of effective drug delivery systems, in terms of their application route and release profile, is crucial for improving the therapeutic outcomes of all bioactive compounds. In this study, we explored the encapsulation of 5-fluorouracil, a commonly used chemotherapeutic agent, in poly(lactic acid) films for the first time and the role of chitosan particles in the structure, as no previous studies have examined their potential for this purpose. The objective is to enhance the sustained release of 5-FU and minimise the burst release step while leveraging the biocompatibility and biodegradability of these polymers. PLA films were fabricated using a solvent casting method, and 5-FU was encapsulated either directly within the PLA matrix or loaded into chitosan particles, which were then incorporated into the film. The physicochemical properties of the films, including morphology, wettability, phase state of the drug, thermal stability, drug loading efficiency, and release kinetics, were evaluated along with their barrier and mechanical properties. The results indicate a change in morphology after the addition of the drug and/or particles compared to the empty film. Additionally, the strain value at break decreased from nearly 400% to below 15%. Young’s modulus also changes from 292 MPa to above 500 MPa. The addition of chitosan particles lowered the permeability and vapour transmission rate slightly, while dissolving 5-FU increased them to 241 g/m²·24 h and 1.56 × 10⁻¹³ g·mm/m²·24 h·kPa, respectively. Contact angle and surface energy values went from 71° and 34 mJ/m² for pure PLA to below 53° and around 58 mJ/m² for the composite structures, respectively. Drug release tests, conducted for 8 h, indicated a nearly 2-fold decrease in the amount of drug released from the film with particles within this period, from around 45% for bare particles and PLA film to 25% for the combined structure, indicating the potential of this system for sustained release of 5-FU. Full article

The precise control of thermal–kinetic parameters governs epitaxial perfection in functional oxide heterostructures. Herein, using Iridium/MgO(100) as a model system, the traditional “low-speed/high-temperature” paradigm is revolutionized through the combination of ab initio calculations, multiscale simulations, and subsequent deposition experiments. First-principles modeling reveals the mechanisms of Volmer–Weber (VW, island growth mode) nucleation at low coverage and Stranski–Krastanov (SK, layer-plus-island growth) transitions driven by interface metallization, stress release, and energy reduction, which facilitates coherent monolayer formation by lowering the energy barrier by ~34%. Molecular dynamics simulations demonstrate that the strategic co-optimization of substrate temperature (T_sub) and deposition rate (V_dep) induces an abrupt cliff-like drop in mosaic spread. Experimental validations confirm that this T-V synergy achieves unprecedented interfacial coherence, whereby AFM roughness reaches 0.34 nm (RMS) and the XRC-FWHM of 0.13° approaches single-crystal benchmarks. Notably, our novel “accelerated heteroepitaxy” protocol reduces growth time without compromising quality, addressing the efficiency–quality paradox in industrial-scale diamond substrate fabrication. These findings establish universal thermal–kinetic design principles applicable to refractory metal/oxide heterostructures for next-generation quantum sensors and high-power electronic devices. Full article