Search Results (5,705)

This publication presents an improved manufacturing method for tetrahedral metal effect pigment particles that demonstrates reduced flowlines in injection-molded polymer components compared with conventional platelet-shaped pigment particles. The previously published cold forming process for tetrahedral particles, made entirely from aluminum, faced manufacturing challenges, resulting in a high reject rate due to particle adhesion to the micro-structured mold roller. In contrast, this study introduces a new manufacturing method for tetrahedral particles, now consisting of metallized UV-cured thermoset polymer. These particles, dispersed in amorphous matrix thermoplastics, have shown to maintain their shape during the injection molding process. The manufacturing technique for these novel particles is based on UV imprint lithography, omitting the reject rates compared with the previously presented cold rolling process of tetrahedral full aluminum particles. Thus, the novel manufacturing technique for tetrahedral pigment particles shows increased potential for automation through roll-to-roll manufacturing in the future. Full article

The rheological behavior and low-temperature curing kinetics of poly(ethylene glycol fumarate)–acrylic acid systems initiated by benzoyl peroxide/N,N-dimethylaniline have been investigated for the first time with a focus on the development of thermosetting binders with controllable properties. It has been established that both composition and temperature have a significant effect on rheological behavior and kinetic parameters. Rheological studies revealed non-Newtonian flow behavior and thixotropic properties, while oscillatory tests demonstrated structural transformations during curing. Increasing the temperature was found to accelerate gelation, whereas a higher polyester content retarded the process, which is crucial for controlling the pot life of the reactive mixture. DSC analysis indicated that isothermal curing at 30–40 °C can be satisfactorily described by the Kamal autocatalytic model, whereas at 20 °C, at later stages, and at higher polyester contents, diffusion control becomes significant. The thermal behavior of cured systems was investigated using thermogravimetry. Calculations using the isoconversional Kissinger–Akahira–Sunose and Friedman methods confirmed an increase in the apparent activation energy for thermal decomposition, suggesting a stabilizing effect of poly(ethylene glycol fumarate) in the polymer structure. The studied systems are characterized by controllable kinetics, tunable viscosity, and high thermal stability, making them promising thermosetting binders for applications in composites, construction, paints and coatings, and adhesives. Full article

Waste management poses escalating threats to environmental sustainability, particularly with municipal solid waste (MSW) growth. Incineration, a widely adopted method for reducing waste volume, produces millions of tons of municipal solid waste incineration fly ash (MSWIFA) each year. Despite its high toxicity and classification as a hazardous solid waste, its ultrafine particle size and pozzolanic activity offer potential for its use in construction materials. In this study, MSWIFA was used to replace 6%, 12%, 18% and 24% of cementitious materials, and the effect of MSWIFA substitution rate on the workability, mechanical properties, microstructure, and durability of UHPC was studied. Furthermore, the study assessed the solidification capacity of the UHPC for heavy metal ions and quantitatively analyzed its eco-economic benefits. The results show that, under standard curing conditions, substituting 12% of cementitious materials with MSWIFA significantly modified UHPC hydration, shortened setting time, reduced fluidity, and increased wet packing density. The 28-day compressive strength reached 134.63 MPa, comparable to the control group. Concurrently, fluidity, durability, and heavy metal leaching all met the required standards, with energy consumption reduced by 14.86%, carbon emissions lowered by 12.76%, and economic costs decreased by 6.41%. This study provides a feasible solution for recycling MSWIFA into non-hazardous concrete, facilitating sustainable hazardous waste management and mitigating heavy metal-related environmental pollution. Full article

This study aimed to evaluate the impact of different adhesive solutions on the surface roughness and hardness of denture base materials. Twenty specimens (20 × 20 × 5 mm) were produced for each material group: heat-cured ProBase Hot^®, 3D-printed NextDent Denture 3D+^®, and PMMA-milled Exaktus^®. They were then divided into five solution subgroups (n = 4): control (T0), distilled water, Corega PowerMax^®, Elgydium Fix^®, and Kukident Pro Ultimate^®. Specimens were immersed in the solution at 37 °C daily for 28 days, simulating continuous use. Profilometry and Shore D hardness tests were performed at baseline and after 28 days of the immersion protocol. Data analysis was done using IBM SPSS Statistics 30.0, considering a confidence level of 0.05. At baseline, the materials differed in surface roughness and Shore D hardness, with the 3D-printed group showing the highest median values for the Rz parameter (p = 0.023) and the lowest for hardness (p = 0.023). Elgydium Fix had a significant effect on the heat-cured resin, with increased Rz and decreased hardness. Kukident caused higher roughness and lower hardness in the 3D-printed and milled resins (not significant). Corega showed minor effects in all tested materials. In conclusion, the denture base material and the adhesive formulation influence the physical and mechanical properties of denture base resins. Full article

Consumer demand for organic and nitrite-free meat products has stimulated the search for sustainable alternatives to synthetic curing agents. Conventional nitrites are effective in stabilizing color, inhibiting lipid oxidation, and suppressing pathogens, but their use raises health concerns due to potential nitrosamine formation. This study investigated the application of Portulaca oleracea powder as a multifunctional ingredient to fully replace sodium nitrite in organic cooked frankfurters. Two formulations were produced: control frankfurters with sodium nitrite and experimental frankfurters with purslane powder 1.2%. Physicochemical, oxidative, proteomic, and antioxidant parameters were monitored during refrigerated storage. Purslane incorporation improved the lipid profile by increasing α-linolenic acid and lowering the ω-6/ω-3 ratio, while peroxide, thiobarbituric acid reactive substances (TBARS), and acid values remained significantly lower than in nitrite-containing controls after 10 days. Protein oxidation was also reduced, and SDS-PAGE profiles confirmed that the major structural muscle proteins remained stable, indicating that purslane addition did not disrupt the core proteome. Antioxidant assays showed strong ferric-reducing antioxidant power (FRAP) activity 13.7 mg GAE/g and enhanced 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity 22.3%, highlighting purslane’s contribution to oxidative stability. Although redness (a*) was lower than in nitrite controls, overall color stability (L*, b*) remained high. Taken together, purslane enhanced oxidative stability and quality attributes of nitrite-free organic frankfurters; microbiological validation is ongoing and will be reported separately. Full article

Survival rates for those with metastatic osteosarcoma (OS) have not improved over the last four decades. It is imperative that novel approaches to treating and curing OS be sought. We, therefore, turned our attention to Brusatol (Bru), a naturally occurring Nrf2 inhibitor reported to elicit anti-cancer effects in a multitude of tumour models. Importantly there is emerging evidence that Nrf2 is implicated in chemoradiotherapy resistance in OS and that inhibiting Nrf2 may represent a desirable route to treating OS. Surprisingly, using the human OS cell line, MG63, we actually found that Bru promoted cell growth. Compared to control, normoxic cultures, the application of Bru (50 nM) over 3 days led to an increase in cell number by approximately 1.7-fold. A similar outcome occurred for cells under hypoxic conditions, although the extent of cell growth was significantly less at around 1.3-fold. Furthermore, Bru prevented MG63 differentiation in response to co-treatment with the calcitriol analogue, EB1089, and the lipid growth factor, lysophosphatidic acid. The extent of inhibition was profound at approximately 2.8-fold. The application of the Nrf2 activator, dimethyl fumarate, did not rescue these phenotypes. Whilst Bru has shown promise in other cancer models, it would appear, from our findings, that this agent may not be suitable for the treatment of OS. Full article

This study investigated the effect of piranha solution etching duration on the shear bond strength of zirconia ceramics bonded to resin cement, comparing it to conventional sandblasting treatment. Fifty fully sintered zirconia specimens (6.0 mm diameter, 4.0 mm thickness) were prepared and randomly divided into five groups (n = 10): sandblasting control and piranha solution treatment for 1, 2, 3, and 4 min. Piranha solution was prepared by mixing 98% H₂SO₄ and 35% H₂O₂ in a 3:1 ratio. All specimens were bonded to resin composite cylinders using dual-cure resin cement. Shear bond strength testing was performed using a universal testing machine at a 0.5 mm/min crosshead speed. Failure modes were analyzed using a stereomicroscope and classified as adhesive, cohesive, or mixed failures. One-way ANOVA revealed significant differences between groups (p < 0.05). Tukey’s post hoc test showed that 1-min piranha treatment produced significantly lower bond strength (7.64 ± 2.02 MPa) compared to all other groups. The 2-min (15.17 ± 2.79 MPa), 3-min (14.99 ± 3.27 MPa), and 4-min (18.34 ± 3.15 MPa) piranha treatments showed no significant differences compared to sandblasting (15.41 ± 2.61 MPa). Failure mode analysis revealed 100% adhesive failures for the 1-min group, while all other groups showed 80% adhesive and 20% mixed failures. Piranha solution treatment duration significantly affected zirconia bonding performance. While 1-min treatment proved inadequate, 2–4 min treatments achieved bond strengths comparable to sandblasting. The findings suggest that piranha solution treatment for 2–4 min represents a viable alternative to sandblasting for zirconia surface preparation, with the 2-min protocol being the most efficient choice for clinical application. Full article

Radiation-induced intestinal injury (RIII), a severe complication of abdominopelvic radiotherapy, causes intestinal ischemia, ulcers, and necrosis, severely impacting patients’ quality of life. Currently, effective treatments are limited, and a specific cure remains elusive. Our previous research showed that lactoferrin (LF) can promote intestinal stem cell (ISC) proliferation and tissue repair; however, its oral administration is limited by rapid degradation in the gastric environment. In this study, we developed LF-loaded liposomal nanoparticles (Lip-LF) using a simple ethanol injection method. The optimal formulation (cholesterol/egg yolk lecithin ratio 2:8, LF concentration 12.5 mg/mL) achieved a drug-loading capacity of 6.8% and a narrow size distribution (0.2 < PDI < 0.4). In vitro experiments demonstrated that Lip-LF protected LF from pepsin degradation in simulated gastric fluid (SGF), retaining over 80% integrity after 120 min, while releasing in simulated intestinal fluid (SIF). In vivo imaging revealed prolonged gastrointestinal retention of Lip-LF compared to free LF. In a murine model of RIII (12 Gy whole-body irradiation), Lip-LF significantly restored villus counts, increased crypt height, and promoted goblet-cell regeneration. Immunohistochemical and qPCR analyses revealed enhanced ISCs proliferation and upregulation of repair-associated genes, including Pcna and Olfm4. These findings demonstrate that Lip-LF protects LF from gastric degradation and enhances its targeted delivery to the intestine, improving its therapeutic efficacy in repairing RIII. Lip-LF thus offers a promising strategy for managing RIII. Full article

Road and pavement construction require huge volumes of borrowed soils in addition to the foundation soils. Unfortunately, not all soils are suitable for construction purposes. Soil stabilization is a fundamental technique used to enhance the engineering properties of weak ground/soil to meet the demands of large infrastructure projects, such as roads. It is in this regard that this study investigates the strength development, durability, and effectiveness of cement and quarry dust as stabilizers to enhance the geotechnical properties of a weak tropical clay soil. Cement was added in the range of 0% to 10% while quarry dust was used to partially replace soil in the range of 0% to 50%. The results show significant improvements in the Atterberg limits and strength properties of the tropical clay. The liquid limit reduced from 43.2% to 25.1% while the plasticity index reduced from 17.6% to 10.2% at 50% quarry dust and 10% cement content. Similarly, the maximum dry unit weight increased from 17.4 kN/m³ to 21.3 kN/m³ while the optimum moisture content decreased from 17.1% to 12.9%. The maximum soaked CBR value was 172%, representing a 1497% enhancement over untreated soil. Also, the maximum unconfined compressive strength (UCS) reached 2566 kN/m² at 28 days of curing, representing a 1793.73% increase when compared to the untreated soil. Cement content was found to be the predominant factor influencing strength development. The study shows that cement–quarry dust blends compacted at high energy can be adopted in sustainable road construction. Full article

Although methotrexate (MTX) is a magnificent cure for cancerous neoplasms and inflammatory disorders, its usage is bound due to associated hazards, especially nephrotoxicity. The present study investigated the possible therapeutic impact of alogliptin (ALO), prescribed for managing type 2 diabetes, on renal injury caused by MTX and explored the mechanisms that could illustrate this suggested protective effect. Four rat groups were involved: control, ALO (20 mg/kg/d, intragastrically (I.G.)) for ten days, MTX, and MTX + ALO groups. The latter two groups were given MTX (20 mg/kg, I.P.) on the 7th day, while the MTX + ALO group was administered ten days of 20 mg/kg of ALO. A significant impairment in renal function, catalase activity, reduced glutathione content, nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) expressions, coupled with an increase in kidney injury molecule-1 (KIM-1), malondialdehyde, tumor necrosis factor-alpha (TNF-α), and cleaved caspase-3 (c-caspase-3) expressions, was observed in MTX-intoxicated rats, evidenced by remarkable deterioration in renal construction. Conversely, ALO improved renal function and architecture. Moreover, ALO retrieved the oxidative balance, the attenuated Nrf2/HO-1 expression, and the elevated KIM-1, TNF-α, and c-caspase-3 expression. In conclusion, ALO might abrogate MTX-elicited kidney damage by rectifying the deviation in oxidative status, apoptotic and inflammatory pathways, paving the way for managing MTX-induced nephrotoxicity. Full article

Leishmaniasis is a parasitic disease caused by Leishmania spp., transmitted by sandflies, and endemic in 98 countries. Leishmania infantum, the main agent of visceral leishmaniasis in Europe, commonly infects both humans and animals, with dogs as the principal domestic reservoir. Clinical manifestations in dogs depend on the host immune response. A robust Th1 response facilitates macrophage activation and parasite control, while persistently elevated TNF-α and IL-6 can lead to chronic inflammation and tissue damage. Current treatments reduce parasite load but rarely achieve complete cure and are often associated with relapses and resistance. Artemisia annua, source of artemisinin, could be a promising alternative to canine leishmaniasis. Despite its potential, no published studies have investigated its effect specifically against Leishmania infantum as well as its possible dual action: antiparasitic and immunomodulation. We conducted in vitro evaluations of a standardized Artemisia annua extract. Leishmanicidal activity was assessed against both promastigote and amastigote stages, and cytokine modulation was evaluated in RAW 264.7 macrophages. The extract showed strong leishmanicidal activity without cytotoxicity and significantly reduced TNF-α and IL-6 levels under inflammatory conditions, and in both cases, efficiency was correlated with artemisinin content. These results support Artemisia annua as a promising safer therapeutic adjuvant candidate for canine leishmaniasis, targeting both the parasite and the host inflammatory response. Full article

The impregnation and curing process of dry bushing requires the epoxy material for bushing to have a good process performance. In addition, the actual operating conditions of dry bushing put forward high requirements on the dielectric properties of the epoxy material. Amine accelerators can not only improve the technological properties of epoxy materials such as gel time and curing exothermic temperature rise by regulating the reaction rate of epoxy resin and anhydride curing agent, but also optimize the dielectric properties of epoxy materials by regulating the crosslinking density of epoxy materials. However, there are many types of amine accelerators, and the effects of amine accelerators with different nucleophilicity on epoxy materials vary greatly. In this paper, four kinds of amine accelerators with different nucleophilic ability were selected to study the influence of the nucleophilic ability of amine accelerators on the process and dielectric properties of epoxy materials. The results show that the stronger the nucleophilicity of the amine accelerator, the shorter the gel time of the epoxy mixture and the higher the exothermic temperature rise during curing, indicating a poorer processing performance. However, stronger nucleophilicity also endows the epoxy material with superior dielectric properties. Among them, the strong nucleophilic ability of TEA shortens the gel time of the material by 50% and increases the curing exothermic temperature rise by 55.3% compared with the weak nucleophilic ability of the DET epoxy system; the dielectric constant and dielectric loss of the material are reduced by 8.3% and 39.5%, respectively, and the breakdown strength is improved by 11.4%. This paper reveals the contradictory relationship between the process and dielectric performance of epoxy materials triggered by the difference in the nucleophilic ability of amine accelerators, and it also provides a new research idea for the improvement of the process and in the dielectric performance of epoxy materials for dry bushing. Full article

Due to its multiple amino groups, triethylenetetramine (TETA) can be used as an effective formaldehyde scavenger contributing to the reduction in formaldehyde emission from plywood. This study aimed to evaluate the effect of small TETA loadings on the properties of urea-formaldehyde (UF) resin and the performance of the resulting plywood. Adhesive mixtures containing 0%, 0.5%, 1.0%, and 1.5% TETA were prepared and characterized in terms of pH, viscosity, solids content, and gel time. The incorporation of TETA significantly increased adhesive pH and gel time, while viscosity and solid content were not significantly affected. The analysis of formaldehyde content and spectroscopic and thermogravimetric analyses of the cured adhesives showed reduced formaldehyde content, changes in chemical structure, and enhanced thermal stability at lower temperatures but accelerated degradation at higher temperatures. Formaldehyde emission from plywood was reduced; however, bonding quality and mechanical performance decreased with higher TETA content. Nevertheless, the wet shear strength of all variants exceeded 1 N/mm². Adhesive formulation containing 0.5% TETA was selected as the optimal variant, providing environmental benefits while maintaining satisfactory plywood performance. Full article

The combined effects of accelerated carbonation and lime sludge incorporation on the mechanical and durability performance of fiber-cement composites were assessed in this study. Lime sludge was used to replace 0%, 10%, and 20% of the cement in the composites, which were then autoclave-cured and carbonated more quickly for two or eight hours. With LS20-C8 (20% lime sludge, 8 h carbonation) achieving the highest carbonation efficiency (74.0%), X-ray diffraction (XRD) verified the gradual conversion of portlandite into well-crystallized calcium carbonate (CaCO₃). In terms of mechanical performance, LS20-C8 outperformed the control by increasing toughness by 16.7%, flexural strength by 14.2%, compressive strength by 14.6%, and compressive modulus by 20.3%. The properties of LS20-C8 were better preserved after aging under wetting-drying cycles, as evidenced by lower losses of toughness (10.0%) and compressive strength (10.1%) compared to the control (14.6% and 18.3%, respectively). The mechanical improvements were explained by optical microscopy, which showed decreased porosity and an enhanced fiber–matrix interface. Overall, the findings show that adding lime sludge to accelerated carbonation improves durability, toughness, strength, and stiffness while decreasing porosity. This method helps to value industrial byproducts and is a sustainable and efficient way to create long-lasting fiber-cement composites. Full article

Sludge is a common engineering byproduct that poses environmental and land-use challenges when disposed of directly. Converting sludge into high-quality subgrade filling material through solidification is therefore of both engineering and ecological significance. In this study, dynamic triaxial tests were conducted on sludge soils stabilized with mineral-based cementitious binders to investigate the effects of binder content, loading frequency, and curing age on the backbone curve, dynamic shear modulus, maximum shear modulus, ultimate stress amplitude, shear modulus ratio, and damping ratio. Scanning electron microscopy (SEM) was further employed to examine the microstructural evolution of the stabilized soils. The results indicate that increasing binder content and curing age significantly enhance the dynamic shear modulus while reducing the damping ratio, and the modulus exhibits a frequency-dependent behavior within the tested loading range. The modified Hardin-Drnevich constitutive model was successfully applied to fit the experimental data, accurately characterizing the dynamic response of stabilized sludge soils and enabling the development of a normalized model for the dynamic shear modulus ratio. SEM observations confirm that hydration reactions between the binder and soil produce gel products that fill interparticle pores, leading to a denser structure and explaining the observed macroscopic improvements in mechanical behavior. Overall, this work elucidates the dynamic response mechanisms of sludge stabilized with mineral-based cementitious materials and provides theoretical and experimental support for its resource utilization in road engineering applications. Full article