Search Results (1,265)

Fungi contribute to ecosystem function through nutrient cycling and decomposition but may be affected by major disturbances such as fire. Some ecosystems are fire-adapted, such as prairies which require cyclical burning to mitigate woody plant encroachment and reduce litter. While fire suppresses fire-sensitive fungi, pyrophilous fungi may continue providing ecosystem functions. Using litter bags, we measured the litter decomposition at three prairies with unburned and burned sections, and we used Illumina sequencing to examine litter communities. We hypothesized that (H1) decomposition would be higher at unburned sites than burned, (H2) increased decomposition at unburned sites would be correlated with higher overall saprotroph diversity, with a lower diversity in autoclaved samples, and (H3) pyrophilous fungal diversity would be higher at burned sites and overall higher in autoclaved samples. H1 was not supported; decomposition was unaffected by burn treatments. H2 and H3 were somewhat supported; saprotroph diversity was lowest in autoclaved litter at burned sites, but pyrophilous fungal diversity was the highest. Pyrophilous fungal diversity significantly contributed to litter decomposition rates, while saprotroph diversity did not. Our findings indicate that fire-adapted prairies host a suite of pyrophilous saprotrophic fungi, and that these fungi play a primary role in litter decomposition post-fire when other fire-sensitive fungal saprotrophs are less abundant. Full article

Wildfires have become increasingly frequent and destructive environmental hazards, especially in boreal ecosystems facing prolonged droughts and temperature extremes. This study presents an integrated spatio-temporal framework that combines Spatio-Temporal Density-Based Spatial Clustering of Applications with Noise (ST-DBSCAN), Fire Radiative Power (FRP), and the differenced Normalized Burn Ratio (ΔNBR) to characterize the dynamics and ecological impacts of large-scale wildfires, using the extreme 2023 Quebec fire season as a case study. The analysis of 80,228 VIIRS fire detections resulted in 19 distinct clusters across four fire zones. Validation against the National Burned Area Composite (NBAC) showed high spatial agreement in densely burned areas, with Intersection over Union (IoU) scores reaching 62.6%. Gaussian Process Regression (GPR) revealed significant non-linear relationships between FRP and key fire behavior metrics. Higher mean FRP was associated with both longer durations and greater burn severity. While FRP was also linked to faster spread rates, this relationship varied by zone. Notably, Fire Zone 2 exhibited the most severe ecological impact, with 83.8% of the area classified as high-severity burn. These findings demonstrate the value of integrating spatial clustering, radiative intensity, and post-fire vegetation damage into a unified analytical framework. Unlike traditional methods, this approach enables scalable, hypothesis-driven assessment of fire behavior, supporting improved fire management, ecosystem recovery planning, and climate resilience efforts in fire-prone regions. Full article

Speaker burn-in is a controversial practice in the audio world, based on the belief that new devices reach optimal performance only after a certain period of use. Supporters claim it improves component flexibility, reduces initial distortion, and enhances sound quality—especially in the low-frequency range. Critics, however, emphasize the lack of scientific evidence for audible changes and point to the placebo effect in subjective listening tests. They argue that modern manufacturing and strict quality control minimize differences between new and “burned-in” devices. This study cites a standard describing a preliminary burn-in procedure, specifying the exact conditions and duration required. Objective tests revealed slight changes in speaker impedance and amplitude response after burn-in, but these differences are inaudible to the average listener. Notably, significant variation was observed between speakers of the same series, attributed to production line tolerances rather than use-related changes. The study also explored aging processes in speaker materials to better understand potential long-term effects. However, subjective listening tests showed that listeners rated the sound consistently across all test cases, regardless of whether the speaker had undergone burn-in. Overall, while minor physical changes may occur, their audible impact is negligible, especially for non-expert users. Full article

This study presents a detailed analysis of the combustion dynamics of stoichiometric H₂–air and CH₄–air mixtures in a 20 L closed vessel over an initial temperature range of 298–423 K. We integrate experimental pressure–time P(t) measurements with numerical analysis to extract laminar burning velocity (LBV) and deflagration index (K_G) values, and we assess three independent kinetic mechanisms (KiBo_MU, University of San Diego, Lund University) via simulations. For H₂–air, LBV increases from 0.50 m/s at 298 K to 0.94 m/s at 423 K (temperature exponent α ≈ 1.79), while for CH₄–air, LBV rises from 0.36 m/s to 0.96 m/s (α ≈ 2.82). In contrast, the deflagration index K_G decreases by ca. 20% for H₂–air and ca. 30% for CH₄–air over the same temperature span. The maximum explosion pressure (P_max) and peak pressure rise rate ((dP/dt)_max) also exhibit systematic increases with temperature. A comparison with model predictions shows agreement within experiments, providing data for safety modeling and kinetic mechanism validation in H₂- and CH₄-based energy systems. Full article

Fluid resuscitation after thermal injury is paramount to avoid burn shock and restore organ perfusion. Both over- and under-resuscitation can lead to unintended consequences affecting patient outcomes. While many studies have examined systemic effects, limited data exist on how fluid resuscitation impacts burn wound progression in the acute period. Furthermore, the mechanisms underlying burn wound progression remain not fully understood. This study used a swine model to investigate how varying resuscitation levels affect peri-burn wound dynamics. Twenty-seven female Yorkshire pigs were anesthetized, subjected to 40% total body surface area burn and 15% hemorrhage, then randomized (n = 9) to receive decision-support-driven (adequate, 2–4 mL/kg/%TBSA), fluid-withholding (under, <1 mL/kg/%TBSA), or high-constant-rate (over, >>4 mL/kg/%TBSA) resuscitation. Pigs were monitored for 24 h in an intensive care setting prior to necropsy. Laser Doppler Imaging (LDI) was conducted pre-burn and at 2, 6, 12, and 24 h post burn to assess perfusion. Biopsies were taken from burn, peri-burn (within 2 cm), and normal skin. RNA was isolated at 24 h for the qRT-PCR analysis of IL-6, CXCL8, and IFN-γ. At hour 2, LDI revealed increased peri-burn perfusion in over-resuscitated animals vs. under-resuscitated animals (p = 0.0499). At hour 24, IL-6 (p = 0.0220) and IFN-γ (p = 0.0253) were elevated in over-resuscitated peri-burn skin. CXCL8 showed no significant change. TUNEL staining revealed increased apoptosis in over- and under-resuscitated peri-burn skin. Differences in perfusion and cytokine expression based on resuscitation strategy suggest that fluid levels may influence burn wound progression. Full article

Background/Objectives: Burned tissue has traditionally been removed surgically, but the effectiveness of enzymatic debridement with NexoBrid has been reported in burn patients and has gained attention in recent years. This agent was approved for use in Japan in 2023. However, even in Japan, there have been few studies examining its effectiveness in patients with extensive burns. The purpose of this study was to analyze the association of combined NexoBrid and surgical excision with clinical outcomes in extensive burn patients. Methods: Between January 2020 and December 2024, seventeen flame burn patients requiring surgical excision were divided into two groups based on whether NexoBrid was used. Clinical outcomes between the two groups were compared using the propensity score overlap weighting method to adjust for baseline differences. Results: Seven of the patients received combined NexoBrid and surgical excision. After weighting, NexoBrid was significantly associated with a shorter time to complete debridement of burned tissue (difference −4 days, 95% CI −5 to −2) and lower percentage of bacteremia (odds ratio 0.06, 95% CI 0.00 to 0.96). However, no significant differences were observed in the length of ICU stay, the amount of blood transfusion required for complete tissue removal, hospitalization costs, and in-hospital mortality. Conclusions: Combining conventional surgical excision with enzymatic debridement may reduce the time required to complete debridement of burned tissue and decrease the rate of bacteremia. Further studies are needed to evaluate the effectiveness of NexoBrid combined with surgical excision in patients with extensive burns. Full article

In recent years, the region of Valparaíso has faced devastating fires, notably the Viña del Mar fire on 2 February 2024, which affected 9252 hectares. This study analyzes fire behavior in informal settlements and assesses the effectiveness of different construction materials through scaled prototypes of dwellings made from MDF, OSB, TetraPak, and flame-retardant resin composites. Controlled fire experiments were conducted, recording fire spread times and atmospheric conditions. Results confirm significant differences in fire spread rates and structural survival times between materials, highlighting the practical benefit of fire-resistant alternatives. The Kaplan–Meier survival analysis indicates critical time thresholds for rapid flame escalation and structural collapse under semi-open conditions, supporting the need for improved safety measures. Burn pattern observations further revealed the role of wind, thermal radiation, and material properties in fire dynamics. Overall, this study provides experimental evidence aligned with real fire scenarios, offering quantified insights to enhance fire prevention and response strategies in vulnerable settlements. These findings provide an exploratory basis for understanding fire dynamics in informal settlements but do not constitute definitive design prescriptions. Full article

The high-Andean grass Jarava ichu (Poaceae) plays a vital role in water regulation and aquifer recharge. However, its limited use is often linked to forest fires, highlighting the need for sustainable alternatives. Therefore, this study aims to explore the valorization of ichu as a substrate for the cultivation of Pleurotus spp. (P. citrinopileatus, P. djamor, and P. ostreatus) and to evaluate the potential of the residual substrate as a biofertilizer, offering an ecological alternative to grassland burning in the Peruvian Andes. Samples of ichu from the district of Tomás (Lima, Peru) were used as culture substrate, analyzing productivity indicators such as crop cycle (CC), biological efficiency (BE), and production rate (PR), together with the nutritional profile of the fungi and the chemical properties of the residual substrate. The results showed an average biological efficiency of 19.8%, with no significant differences (p > 0.05) in CC, BE, or PR among the species, confirming the viability of ichu as a substrate. The fungi presented a high protein content (24.1–30.41% on a dry basis), highlighting its nutritional value. In addition, the residual substrate exhibited elevated levels of phosphorus (795.9–1296.9 ppm) and potassium (253.1–291.3 ppm) compared to raw ichu (0.11–7.77 ppm for both nutrients). Germination tests on radish seeds showed rates between 80% and 100%, without inhibition, supporting its potential as a biofertilizer. This study demonstrates the double potential of ichu as a substrate for the sustainable production of edible mushrooms of high nutritional value and as a source of biofertilizers. Full article

Objectives: Burning mouth syndrome (BMS) is a chronic, painful, idiopathic condition of the oral cavity, characterized by the absence of visible pathological changes on the oral mucosa and normal laboratory findings. Recent evidence from the literature supports the classification of BMS as a neuropathic condition. It has been proposed that oxidative stress may contribute to neuropathic pain. N-acetylcysteine (NAC) is an antioxidant that exhibits neuroprotective properties. The aim of the study was to evaluate the efficacy of N-acetyl cysteine in the treatment of burning mouth syndrome (BMS). Methods: Eighty female patients with previously diagnosed BMS were randomly assigned to one out of two groups. One group received N-acetyl cysteine (600 mg/twice a day) and the other received placebo, for an eight-week period. The outcome was measured by the Oral Health Impact Profile-14 (OHIP-14) quality of life questionnaire and Numeric Pain Rating Scale, for burning and discomfort, both before and after completing the therapy. Results: Both groups experienced a significant reduction in burning and discomfort sensations, along with a significant improvement in oral health-related quality of life. However, the difference between the treatment and control group was not statistically significant. Conclusions: NAC does not significantly improve the oral health-related quality of life, burning sensations, and discomfort in BMS subjects compared to placebo. Full article

The increasing levels of ozone pollution have become a significant environmental issue in urban areas worldwide. Previous studies have confirmed that the urban ozone pollution in China is mainly controlled by volatile organic compounds (VOCs) rather than nitrogen oxides. Therefore, a study on the emission characteristics and source analysis of VOCs is important for controlling urban ozone pollution. In this study, hourly concentrations of 57 VOC species in four groups were obtained in April 2022, a period of high ozone pollution in Kunming, China. The ozone formation potential analysis showed that the accumulated reactive VOCs significantly contributed to the subsequent ozone formation, particularly aromatics (44.16%) and alkanes (32.46%). In addition, the ozone production rate in Kunming is mainly controlled by VOCs based on the results of the empirical kinetic modeling approach (K_NOx/K_VOCs = 0.25). The hybrid single-particle Lagrangian integrated trajectory model and polar coordinate diagram showed high VOC and ozone concentrations from the southwest outside the province (50.28%) and the south in local areas (12.78%). Six factors were obtained from the positive matrix factorization model: vehicle exhaust (31.80%), liquefied petroleum gas usage (24.16%), the petrochemical industry (17.81%), fuel evaporation (11.79%), coal burning (7.47%), and solvent usage (6.97%). These findings underscore that reducing anthropogenic VOC emissions and strengthening controls on the related sources could provide a scientifically robust strategy for mitigating ozone pollution in Kunming. Full article

Background and Objectives: Older adults are a vulnerable population to unintentional injuries due to age-related physiological decline and the presence of various chronic conditions. Unintentional injuries occurring in the home, such as falls, burns, poisoning, cuts, and suffocation, have been reported at higher rates in this age group compared to younger populations. This study examines the prevalence and types of unintentional in-home injuries in older adults and identifies the risk factors associated with falls and cuts/collisions. Materials and Methods: A cross-sectional study was conducted on 309 older adults (aged ≥ 65 years) recruited from eight senior welfare centers in South Korea. Results: The most frequent cause of injury was falls (28.7%), followed by cuts/collisions (27.0%), burns/fire (11.4%), and other injuries (8.1%). In the model adjusted for age and sex, risk factors for falls included a history of outdoor falls or indoor cuts/collisions, dizziness, and the use of two or more medications. Risk factors for cut/collision injuries included a history of indoor burns or falls, numbness in hands and feet, and visual impairment. Conclusions: To effectively prevent home injuries among older adults, it is crucial to focus not only on falls but also on frequent minor injuries caused by cuts and collisions. Full article

Hydrogen–gasoline dual-fuel spark ignition (SI) engines represent a promising transitional solution toward cleaner combustion and reduced carbon emissions. In a previous study, a predictive engine model was developed to simulate the performance and combustion characteristics of such systems; however, its accuracy was constrained by the use of estimated combustion parameters. This study presents an experimental validation based on high-resolution in-cylinder pressure measurements performed on a naturally aspirated SI engine operating with a 20% hydrogen energy share. The objectives are twofold: (1) to refine the combustion model using empirically derived combustion metrics, and (2) to evaluate the feasibility of moderate hydrogen enrichment in a stock engine configuration. To facilitate a more accurate understanding of how key combustion parameters evolve under different operating conditions, Vibe function was fitted to the ensemble-averaged heat release rate curves computed from 100 consecutive engine cycles at each static full-load operating point. This approach enabled the extraction of stable and representative metrics, including the mass fraction burned at 50% (MFB50) and combustion duration, which were then used to recalibrate the predictive combustion model. In addition, cycle-to-cycle variation and combustion duration were also investigated in the dual-fuel mode. The combustion duration exhibited a consistent and substantial reduction across all of the examined operating points when compared to pure gasoline operation. Furthermore, the cycle-to-cycle variation difference remained statistically insignificant, indicating that the introduction of 20% hydrogen did not adversely affect combustion stability. In addition to improving model accuracy, this work investigates the occurrence of abnormal combustion phenomena—including backfiring, auto-ignition, and knock—under enriched conditions. The results confirm that 20% hydrogen blends can be safely utilized in standard engine architectures, yielding faster combustion and reduced burn durations. The validated model offers a reliable foundation for further dual-fuel optimization and supports the broader integration of hydrogen into conventional internal combustion platforms. Full article

This study investigated the combustion performance of pig manure, straw, and coal at various blending ratios using thermogravimetric analysis. The synergistic effect of coal and pig manure at various ratios was analyzed, and kinetic analysis was performed using the Coats–Redfern method. The results showed that the overall combustion performance and stability of the blended fuel improved as the blending ratio of pig manure and straw increased. Increasing the ratio of pig manure reduced the ignition temperature of blended fuel from 696 K to 675 K. Additionally, the combustion of pig manure and coal exhibited a significant synergistic effect, strongest at a 5% blending ratio. For combustion reactions with conversion rates between 0.2 and 0.8, the activation energy required was 75.82 kJ mol⁻¹ for a 10% pig manure blending ratio and 44.33 kJ mol⁻¹ for a 30% blending ratio. These results demonstrate that lower activation energies suggest that the combustion reaction is more likely to proceed. The activation energy of straw was higher than that of pig manure at all blending ratios. These findings suggest that pig manure burns more easily when blended with coal than straw. Full article

Assessments of subway train fires were conducted based on full-scale experiments and numerical simulations. The experimental platform and simulation model were established according to a real subway train in China. The results show that there was no obvious flame spread, and all the electrical circuitry maintained its integrity during a standard luggage fire. The maximum HRR (heat release rate) of the luggage fire obtained through the full-scale experiment was 155.5 kW, which was almost the same as the standard HRR curve provided in EN 45545-1. However, the fire only lasted approximately 180 s, which was much shorter than a standard fire (600 s). Through numerical simulations of an entire subway train, the side wall and roof ignited quickly, and the fire continually spread to the adjacent compartment under the extreme scenario with a gasoline pool fire and exposed winterproof material. The maximum HRRs of the luggage and gasoline pool fires were 179.7 and 17,800.0 kW, respectively. According to the experimental and simulation results, the Duggan method, which assumes that all combustibles inside a train compartment burn at the same time, was not appropriate for assessing the fires in the subway train, and a simple revised frame was proposed instead. Full article

This study presents a global aerosol climatology derived from six years (October 2018–October 2024) of the Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) observations, using a U-Net Convolutional Neural Network (CNN) machine learning algorithm for Cloud–Aerosol Discrimination (CAD). Despite ICESat-2’s design primarily as an altimetry mission with a single-wavelength, low-power, high-repetition-rate laser, ICESat-2 effectively captures global aerosol distribution patterns and can provide valuable insights to bridge the observational gap between the Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) and Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) missions to support future spaceborne lidar mission design. The machine learning approach outperforms traditional thresholding methods, particularly in complex conditions of cloud embedded in aerosol, owing to a finer spatiotemporal resolution. Our results show that annually, between 60°S and 60°N, 78.4%, 17.0%, and 4.5% of aerosols are located within the 0–2 km, 2–4 km, and 4–6 km altitude ranges, respectively. Regional analyses cover the Arabian Sea (ARS), Arabian Peninsula (ARP), South Asia (SAS), East Asia (EAS), Southeast Asia (SEA), the Americas, and tropical oceans. Vertical aerosol structures reveal strong trans-Atlantic dust transport from the Sahara in summer and biomass burning smoke transport from the Savanna during dry seasons. Marine aerosol belts are most prominent in the tropics, contrasting with earlier reports of the Southern Ocean maxima. This work highlights the importance of vertical aerosol distributions needed for more accurate quantification of the aerosol–cloud interaction influence on radiative forcing for improving global climate models. Full article