Search Results (1,274)

Introduction: Extrinsic skin damage is often a result of oxidative stress caused by exposure to environmental factors such as ultraviolet (UV) radiation, ozone (O₃), and various pollutants. As a result, topical antioxidants have been evaluated for their effectiveness in mitigating or reversing skin damage caused by environmental factors. Topical antioxidants containing a combination of l-ascorbic acid, tocopherol, and ferulic acid have significantly improved markers of skin health after exposure to environment-induced skin damage. However, research suggests that l-ascorbic acid and tocopherol tend to be relatively unstable, possibly affecting their efficacy against outdoor stressor damage. It has been shown that ferulic acid significantly improves the stability of both l-ascorbic acid and tocopherol, but its long-term stabilization effects on these antioxidants are relatively unknown. Material and Methods: This study evaluated the time-dependent effectiveness of a topical antioxidant mix containing 15% l-ascorbic acid, 1% tocopherol, and 0.5% ferulic acid (AOX) on UV-induced skin damage. Skin biopsies (12 mm, n = 60) were placed in a 6-well plate with medium and incubated at 37 °C and 5% CO₂ overnight. The day after, skin samples were pretreated with 10 µL of differently aged AOX (0-, 6-, 12-, and 36-month-old) and then exposed to different doses of UV light (100, 200, 400 mJ/cm²) daily over four days. AOX formulations were stored in a cool, dry, and dark place at approximately 20–22 °C during the whole study. This study evaluated 4-hydroxynonenal (4-HNE) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) as oxidative damage and skin DNA damage markers, Collagen1 and Filaggrin as skin structure, and IL-8 and Nrf2 as inflammatory and defensive response. Results: UV exposure significantly increased oxidative and inflammatory markers in human skin explants affecting also filaggrin and collagen levels. However, pre-treatment with the antioxidant formulation, particularly in its younger formulations (0-, 6-, and 12-month-old), significantly reduced the damaging effect of UV. Additionally, all antioxidant formulations effectively mitigated UV-induced damage across all doses. Conclusions: Our results indicate that pre-treatment with this formulation consistently reduces UV-induced oxidative damage and DNA damage in human skin explants, regardless of the formulation age and the discoloration state. Although effective, the protective capacity of aged formulations may be reduced only when extreme UV exposure is tested, a condition that is unlikely to occur under typical environmental conditions. These results support ferulic acid as a stabilization agent for topical antioxidant mixtures. Full article

Background/Objectives: Cancer represents a significant health challenge, with high mortality and morbidity rates. Its diagnosis often triggers chronic stress, adversely affecting patient outcomes. Exercise has emerged as complementary therapy, enhancing treatment adherence and mitigating the side effects of chemotherapy. This study examines the effects of mild exercise during chemotherapy on patient anxiety. Methods: This prospective paired cohort study was conducted in the General Oncology Hospital of Kifisia “Agioi Anargyroi” in Athens, Greece. Adult cancer patients undergoing chemotherapy participated, excluding those with cognitive, hearing, or motor impairments, those who experienced side effects, or those who declined consent. Anxiety was measured before and after a 20-minute exercise routine performed during chemotherapy, using the Greek-translated State–Trait Anxiety Inventory (STAI). The exercise regimen included warm-up, full-body stretching, and cool-down exercises. Pre- and post-exercise scores were analyzed using the Wilcoxon signed-rank test. Results: Forty-five patients (20 women, 25 men; mean age 69.02 ± 10.62 years) with various cancer backgrounds participated. Pre-intervention anxiety levels were in the borderline “moderate” range, dropping post-exercise to the “low” range. Mean STAI scores decreased from 37.73 ± 13.33 to 32.00 ± 14.22 (p < 0.0001), with a medium-large effect size (Cohen’s d for paired samples = −0.646). No significant correlation was found between age and anxiety scores. Discussion: This study found a significant short-term reduction in anxiety, suggesting that incorporating mild exercise during chemotherapy may help in alleviating patient stress. The medium-to-large effect size supports the potential for meaningful short-term benefits. Conclusions: Incorporating mild exercise during chemotherapy may help reduce anxiety and psychological burden. These findings underscore the need for more comprehensive research in larger, more diverse populations to better understand the benefits of incorporating mild exercise during chemotherapy. Full article

To address the central cracking problem in continuous casting slabs of 38CrMoAl steel, high-temperature tensile tests were performed using a Gleeble-3800 thermal simulator to characterize the hot ductility of the steel within the temperature range of 600–1200 °C. The phase transformation behavior was computationally analyzed via the Thermo-Calc software, while the microstructure, fracture morphology, and precipitate characteristics were systematically investigated using a metallographic microscope (MM), a field-emission scanning electron microscope (FE-SEM), and transmission electron microscopy (TEM). Additionally, the effects of different holding times and cooling rates on the microstructure and precipitates of 38CrMoAl steel were also studied. The results show that the third brittle temperature region of 38CrMoAl steel is 645–1009 °C, and the fracture mechanisms can be classified into three types: (I) in the α single-phase region, the thickness of intergranular proeutectoid ferrite increases with rising temperature, leading to reduced hot ductility; (II) in the γ single-phase region, the average size of precipitates increases while the number density decreases with increasing temperature, thereby improving hot ductility; and (III) in the α + γ two-phase region, the precipitation of proeutectoid ferrite promotes crack propagation and the dense distribution of precipitates at grain boundaries causes stress concentration, further deteriorating hot ductility. Heat treatment experiments indicate that the microstructures of the specimen transformed under water cooling, air cooling, and furnace cooling conditions as follows: martensite + proeutectoid ferrite → bainite + ferrite → ferrite. The average size of precipitates first decreased, then increased, and finally decreased again with increasing holding time, while the number density exhibited the opposite trend. Therefore, when the holding time was the same, reducing the cooling rate could increase the average size of the precipitates and decrease their number density, thereby improving the hot ductility of 38CrMoAl steel. Full article

This study proposes a new air treatment system that integrates dehumidification, cooling, and water recovery using a Horizontal Air–Ground Heat Exchanger (HAGHE) combined with Peltier cells. The airflow generated by a fan flows through an HAGHE until it meets a septum on which Peltier cells are placed, and then separates into two distinct streams that lap the two surfaces of the Peltier cells: one stream passes through the cold surfaces, undergoing both sensible and latent cooling with dehumidification; the other stream passes through the hot surfaces, increasing its temperature. The two treated air streams may then pass through a mixing chamber, where they are combined in the appropriate proportions to achieve the desired air supply conditions and ensure thermal comfort in the indoor environment. A Computational Fluid Dynamics (CFD) analysis was carried out to simulate the thermal interaction between the HAGHE and the surrounding soil. The simulation focused on a system installed under the subtropical climate conditions of Nairobi, Africa. The simulation results demonstrate that the HAGHE system is capable of reducing the air temperature by several degrees under typical summer conditions, with enhanced performance observed when the soil is moist. Condensation phenomena were triggered when the relative humidity of the inlet air exceeded 60%, contributing additional cooling through latent heat extraction. The proposed HAGHE–Peltier system can be easily powered by renewable energy sources and configured for stand-alone operation, making it particularly suitable for off-grid applications. Full article

The thermo-chemical treatment of dental implants leads to the formation of sodium titanate crystals on their surface. When in contact with blood, these crystals dissolve and trigger an ionic exchange cascade, resulting in the formation of a calcium apatite layer. This study, carried out both in vitro and in an animal model, aimed to determine whether the cooling rate of the treatment affects the size of the deposited crystals, and whether this in turn influences wettability and early bone-to-implant contact (BIC). A total of 50 dental implants and 50 titanium discs were treated using four different cooling rates, along with a control group. Crystal size was analyzed on implant surfaces using scanning electron microscopy, and wettability was assessed on titanium discs using a goniometer. Finally, the implants were placed in the tibiae of 13 rabbits, and histological analysis was performed after three weeks to compare BIC among groups. Results suggest that a cooling rate of 75 °C/h produces smaller sodium titanate crystals, which are associated with significantly improved surface wettability and a higher percentage of bone-to-implant contact after 3 weeks of healing (p < 0.05). Full article

This study proposes a laser texturing method to optimize adhesion and minimize residual stresses in CVD diamond films deposited on tungsten carbide (WC-Co). WC-5.8 wt% Co substrates were textured with quadrangular pyramidal patterns (35 µm) using a 1064 nm nanosecond-pulsed laser, followed by chemical treatment (Murakami’s solution + aqua regia) to remove surface cobalt. Diamond films were grown via HFCVD and characterized by Raman spectroscopy, EDS, and Rockwell indentation. The results demonstrate that pyramidal texturing increased the surface area by a factor of 58, promoting effective mechanical interlocking and reducing compressive stresses to −1.4 GPa. Indentation tests revealed suppression of interfacial cracks, with propagation paths deflected toward textured regions. The pyramidal geometry exhibited superior cutting post-deposition cooling time for stress relief from 3 to 1 h. These findings highlight the potential of laser texturing for high-performance machining tool applications. Full article

Straw-returning is an effective way to improve straw utilization efficiency and reduce environmental pollution. Various straw-returning methods exist; however, their effects on soil microbial diversity and community composition in cool regions have been little studied. This study investigated the changes of soil microbial diversity and community composition under three straw-returning methods, i.e., straw mulching, straw mulching and overturning, straw crushed and mixed, as compared to straw removal as control. The results showed that straw-returning could alter the soil microbial community composition and abundance compared with straw removal. Alpha diversity analysis showed that straw mulching treatment, and straw crushed and mixed treatment significantly increased the diversity of both soil bacteria and fungi compared with straw mulching and overturning treatment. Moreover, this study preliminarily screened Trichoderma, Chaetomium and Streptomyces as potential straw-degrading microorganisms. This study provides basis for further enhancement of straw degradation by using soil microorganisms and sheds light on future work for improving straw degradation efficiency. Full article

AISI 347H stainless steel is widely used in high-temperature environments due to its excellent creep strength and oxidation resistance; however, its corrosion performance remains highly sensitive to thermal oxidation, and the effects of thermal history on its passive film stability are not yet fully understood. This study addresses this knowledge gap by systematically investigating the influence of solution treatment on the corrosion and oxidation resistance of AISI 347H stainless steel. The specimens were subjected to solution heat treatment at 1050 °C, followed by air cooling, and then evaluated through electrochemical testing, high-temperature oxidation experiments at 550 °C, and multiscale surface characterization techniques. The solution treatment refined the austenitic microstructure by dissolving coarse Nb-rich precipitates, as confirmed by SEM and EBSD, and improved passive film integrity. The stabilizing effect of Nb also played a critical role in suppressing sensitization, thereby enhancing resistance to intergranular attack. Electrochemical measurements and EIS analysis revealed a lower corrosion current density and higher charge transfer resistance in the treated samples, indicating enhanced passivation behavior. ToF-SIMS depth profiling and oxide thickness analysis confirmed a slower parabolic oxide growth rate and reduced oxidation rate constant in the solution-treated condition. At 550 °C, oxidation was suppressed by the formation of compact, Cr-rich scales with dual-distributed Nb oxides, effectively limiting diffusion pathways and stabilizing the protective layer. These findings demonstrate that solution treatment is an effective strategy to improve the long-term corrosion and oxidation performance of AISI 347H stainless steel in harsh service environments. Full article

Flash thermal pretreatment (FTT) is a promising technique for enhancing virgin olive oil (VOO) quality. This study investigated the effects of FTT, both cooling (15–25 °C) and heating (30–40 °C), on phenolics, tocopherols, fatty acid composition, oxidative stability (OSI), antioxidant capacity (AC), and volatile composition in VOOs from three Croatian varieties: Istarska Bjelica, Levantinka, and Oblica. A full factorial experimental design was used with two independent variables: treatment temperature and olive variety. Olive pastes were treated after crushing and before malaxation. Data were evaluated using ANOVA, partial least squares (PLS) regression, and response surface methodology (RSM). Istarska Bjelica showed the highest OSI improvement (+16%) mostly linked to elevated phenolic compounds. Levantinka exhibited moderate responses, with slight OSI and AC declines. Oblica was most sensitive to heating, showing OSI and AC reductions (up to 28%), despite increased oleocanthal and olacein. RSM identified optimal FTT temperatures for each variety: 18.9 °C (Istarska Bjelica), 15.4 °C (Levantinka), and 15.5 °C (Oblica). These findings support variety-specific FTT as an effective strategy to improve VOO functional and sensory quality. Full article

The phase transformations of Crucible Particle Metallurgy (CPM) American Iron and Steel Institute (AISI) M4 steel were studied during heat treatments using a CALPHAD-based method. The calculated results were compared with experimental observations. The optimum austenitizing temperature was determined to be about 1120 °C using Thermo-Calc software (2024b). Air-cooling and quenching treatments led to the formation of martensite with a hardness of 63–65 Rockwell C (HRC). The annealing treatment promoted the formation of the equilibrium ferrite and carbide phases and resulted in a hardness of 24 HRC. These findings with regard to phases and microconstituents are in agreement with the predictions derived from a Thermo-Calc-calculated time–temperature–transformation diagram at 1120 °C. Additionally, the primary carbides, MC and M₆C, which formed prior to the heat treatment and had a minor influence on the quenched hardness. In contrast, the tempering process primarily led to the formation of fine secondary M₆C carbides, which hardened the tempered martensite to 57 HRC. The present work demonstrates the application of a CALPHAD-based methodology to the design and microstructural analysis of tool steels. Full article

In wet subtropical environments, perennial groundcovers are common in horticultural plantations to protect the soil from erosion. However, there has been little investigation into whether seeding annual cover crops into the perennial groundcovers provides additional soil services including carbon and nutrient cycling in these systems. To investigate this, farmer participatory field trials were conducted in commercial avocado, macadamia, and coffee plantations in the wet Australian subtropics. Cover crops were direct-seeded into existing inter-row groundcovers in winter (cool season cover crops), and into the same plots the following summer (warm season cover crops). Inter-row biomass was quantified at the end of winter and summer in the control (no cover crop) and cover crops treatments. Soil carbon and nutrient cycling parameters including hot water extractable carbon, water soluble carbon, autoclavable citrate-extractable protein and soil enzyme activities were quantified every two months from early spring (September) 2021 to late autumn (May) 2022. Seeded cover crops produced 500 to 800 kg ha⁻¹ more total inter-row biomass over winter at the avocado coffee sites, and 3000 kg ha⁻¹ biomass in summer at the coffee site. However, they had no effect on biomass production in either season at the macadamia site. Soil functional parameters changed with season (i.e., time of sampling), with few significant effects of cover crop treatments on soil function parameters across the three sits. Growing a highly productive annual summer cover crop at the coffee site led to suppression and death of perennial groundcovers, exposing bare soil in the inter-row by 3 weeks after termination of the summer cover crop. Annual cover crops seeded into existing perennial groundcovers in tree crop systems had few significant impacts on soil biological function over the 12-month period, and their integration needs careful management to avoid investment losses and exacerbating the risk of soil erosion on sloping lands in the wet subtropics. Full article

Creeping bentgrass (Agrostis stolonifera L.) is an important cool-season turfgrass species widely used for golf course putting greens; however, it experiences a summer stress-induced quality decline in the U.S. transition zone and other regions with similar climates. The objective of this study was to determine the effects of five amino acid biostimulants on creeping bentgrass drought and heat stress tolerance. The five biostimulants, including Superbia, Amino Pro V, Siapton, Benvireo, and Surety, at the rate of 0.22 g of N m⁻², were applied biweekly to foliage, and the treatments were arranged in a randomized block design with four replications and were subjected to 56 days of heat and drought stress in growth chamber conditions. The amino acid biostimulants Superbia and Amino Pro V improved the turf quality, photochemical efficiency (PE), normalized difference vegetation index (NDVI), chlorophyll content, antioxidant enzyme superoxide dismutase activity, root growth, and viability and suppressed leaf H₂O₂ levels when compared to a control. Among the treatments, Superbia and Amino Pro V exhibited greater beneficial effects on turf quality and physiological fitness. The results of this study suggest that foliar application of amino acid biostimulants may improve the summer stress tolerance of cool-season turfgrass species in the U.S. transition zone and other regions with similar climates. Full article

Theobroma cacao L. (cocoa) pod husk, a byproduct of the chocolate industry, has potential for commercial applications due to its bioactive compounds. This study aimed to determine the phytochemical composition, biological activity, and clinical efficacy of a standardized extract. This study compared 80% ethanol (CE) and 80% ethanol acidified (CEA) as extraction solvents. The result indicated that CEA yielded higher total phenolic content (170.98 ± 7.41 mg GAE/g extract) and total flavonoid content (3.91 ± 0.27 mg QE/g extract) than CE. Liquid chromatography–tandem mass spectrometry (LC/MS/MS) identified various phenolic and flavonoid compounds. CEA demonstrated stronger anti-oxidant (IC₅₀ = 5.83 ± 0.11 μg/mL in the DPPH assay and 234.17 ± 4.01 mg AAE/g extract in the FRAP assay) compared to CE. Additionally, CEA exhibited anti-tyrosinase (IC₅₀ = 9.51 ± 0.01 mg/mL), anti-glycation (IC₅₀ = 62.32 ± 0.18 µg/mL), and anti-collagenase (IC₅₀ = 0.43 ± 0.01 mg/mL), nitric oxide (NO) production inhibitory (IC₅₀ = 62.68 μg/mL) activities, without causing toxicity to cells. A formulated lotion containing CEA (0.01–1.0% w/w) demonstrated stability over six heating–cooling cycles. A clinical study with 30 volunteers showed no skin irritation. The 1.0% w/w formulation (F4) improved skin hydration (+52.48%), reduced transepidermal water loss (−7.73%), and decreased melanin index (−9.10%) after 4 weeks of application. These findings suggest cocoa pod husk extract as a promising active ingredient for skin hydrating and lightening formulation. Nevertheless, further long-term studies are necessary to evaluate its efficacy in anti-aging treatments. Full article

Unveiling temperature patterns within agricultural products remains the most important indicator for their quality assessment during post-harvest treatments. Temperature control and monitoring within vented packages is essential for preserving the quality of perishable goods, such as tomato fruits, by preventing localized temperature maxima that can accelerate spoilage. This study proposes a modeling and simulation approach to systematically investigate how ventilation design choices influence internal airflow distribution and the resulting cooling performance. Our analysis compares three distinct venting configurations (single top vent, single middle vent, and two vents) across two package boundary conditions: an open-top system allowing for dual air exits through the open top boundary and the outlet vent(s), respectively, and a closed-top system with a single exit pathway through the outlet vent(s). All scenarios are simulated to assess airflow patterns, velocity magnitudes, and temperature uniformity within different package designs. Full article

Thermomechanical processing has a significant impact on the porosity and mechanical properties of AISI 316L stainless steel produced by laser powder bed fusion (L-PBF). This work evaluated the effect of three heat treatment conditions: as-built (HT0), annealed at 650 °C for 3 h with air cooling (HT1), and annealed at 1050 °C for 1 h followed by water quenching (HT2), combined with cold and hot rolling at different strain levels. The most pronounced improvement was observed after 20% hot rolling followed by water quenching (HR + WQ), which reduced porosity to 0.05% and yielded the most spherical pores, with a circularity factor ($f_{circle}$) of 0.90 and an aspect ratio (AsR) of 1.57. At elevated temperatures, the matrix becomes more pliable, which promotes pore closure and helps reduce stress concentrations. On the other hand, applying heat treatment without causing deformation resulted in the pores growing and increasing porosity in the build direction. The fractography supported these findings, showing a transition from brittle to more ductile fracture surfaces. Heat treatment combined with plastic deformation effectively reduced internal defects and improved both structural integrity and strength. Full article