Search Results (10,365)

Hydrogen-enriched fuel injection in staged gas-turbine combustors is commonly achieved through jet-in-crossflow (JICF) configurations, where flame stabilization is governed by a local balance between flow-induced strain/mixing and chemical reaction rates. This work investigates turbulent reacting JICF relevant to staged combustion conditions using high-fidelity simulations with adaptive mesh refinement (AMR) and differential-diffusion effects together with Lagrangian particle statistics. Chemistry model uncertainties are incorporated by using a projection method that maps uncertainty estimates from detailed mechanisms into the model used in this work. Results show that the macroscopic flame topology remains in a stable two-branch regime (lee-stabilized and lifted) and is primarily controlled by the jet momentum–flux ratio J. Visualization of the normalized scalar dissipation rate reveals that the flame front resides on the low-dissipation side of intense mixing layers, occupying an intermediate region between over-strained and under-mixed regions. While hydrogen content does not significantly change the global stabilization mode for the cases studied, uncertainty analysis reveals composition-dependent differences that are not apparent in the mean behavior alone. In particular, visualization in Eulerian (χ, T) state-space analysis and particle statistics conditioned on the stoichiometric surface demonstrate that higher-hydrogen cases observe a lower scalar dissipation rate and exhibit substantially reduced variability in OH production under kinetic-parameter perturbations, whereas lower-hydrogen blends experience higher dissipation and amplified chemical sensitivity. These findings highlight that, even in globally similar JICF regimes, the hydrogen content can modify the local response of the flame to kinetic-parameter uncertainty, motivating uncertainty-aware interpretation and design for hydrogen-fueled staging systems. Full article

Currently, the main method for producing the vitamin C precursor 2-keto-l-gulonic acid (2-KLG) is a two-step fermentation process, in which secondary sterilization and fermentation processes result in higher costs and energy consumption. Consequently, the development of a one-step fermentation process is seen as a more desirable approach for 2-KLG production. In this study, we used Gluconobacter oxydans WTF0512 and Ketogulonicigenium vulgare WTF0114 as co-cultured strains for the production of 2-KLG from d-sorbitol via one-step fermentation. The fermentation behaviors of G. oxydans WTF0512 and K. vulgare WTF0114 were initially investigated. Subsequently, the fermentation process and medium were optimized, and the titer of 2-KLG reached 132.99 ± 0.52 g/L, with a molar conversion rate of 92.42%, which, to the best of our knowledge, is the highest production via one-step fermentation reported to date. These findings will provide a basis for developing a more economical large-scale one-step fermentation process for the production of 2-KLG. Full article

Rural hospitals are essential access points for healthcare delivery in the United States, yet they continue to experience disproportionate rates of closure and service disruption that threaten community health, economic stability, and equity. This rapid systematic review synthesizes recent peer-reviewed evidence examining rural hospital closures and service disruptions, with emphasis on financial, policy, workforce, and performance-related factors and their downstream impacts. Guided by PRISMA methodology, four databases were searched for U.S.-based studies published between January 2024 and June 2025. Following screening and consensus-based review, 59 articles met inclusion criteria. Across studies, financial vulnerability, characterized by revenue instability, low patient volumes, unfavorable payer mix, and reliance on non-operating revenue, emerged as a dominant precursor to closure and service reductions. Policy context, particularly Medicaid expansion status, telehealth and broadband infrastructure, and reimbursement adequacy, strongly shaped hospital sustainability. Closures and service disruptions were consistently associated with increased travel distances, reduced access to maternal, surgical, mental health, and chronic care services, higher prices at surviving hospitals, and increased strain on remaining providers. Workforce shortages further compounded these challenges. Collectively, findings demonstrate that rural hospital closures reflect interconnected structural weaknesses rather than isolated organizational failure. Coordinated policy action, targeted financial stabilization, workforce development, and technology-enabled care models are necessary to mitigate continued erosion of rural healthcare access. Full article

Alternariol (AOH) and alternariol monomethyl ether (AME) are major mycotoxins produced primarily by Alternaria alternata on cereal grains and fruits. A. alternata is a causative pathogen of strawberry black spot disease. However, little is known about the characteristics of A. alternata, which was isolated from strawberry products. In the present study, we evaluated the influence of temperature, pH, and relative humidity (RH) on the growth of A. alternata OM1 and its production of AOH and AME on different media including strawberry puree agar medium (SPAM) after its isolation from strawberry jam. The fungal strain showed the highest growth rate at 25 °C under pH 6.5 and RH 97%, while the highest amounts of AOH and AME were produced by the strain at 25 °C under pH 4.5 and RH 97%. Additionally, the strain did not produce AOH and AME on SPAM at 25 °C under RH 92% until 7 days. Moreover, RT-qPCR analysis exhibited that relative expression levels of 2 AOH or AME biosynthetic genes (pksI and omtI) in A. alternata OM1 were up-regulated in YES medium, while they were not in MEB medium. Our results demonstrated that the three key environmental parameters had a significant influence on the growth of A. alternata OM1 and its production of AOH and AME. These findings suggest that storage of strawberries below 25 °C under RH 92% could prevent the production of AOH and AME by A. alternata OM1 on them. Full article

The Daliangshan Fault Zone (DLSFZ) constitutes a key segment of the Xianshuihe–Xiaojiang Fault System (XXFS) and exerts fundamental control on the eastward extrusion of the Sichuan–Yunnan Block (SYB). In this work, we present new slip rate determinations at three key sites (Tekoujiagu, Yeer, Damulo) along its middle-southern segments using UAV-based high-resolution topography and OSL dating. Results yield late Quaternary slip rates of 4.5 ± 1.4, 3.7 ± 1.1, and 5.5 ± 1.0 mm/a, respectively. Combined with previous data, the slip rate is 1.5–3.1 mm/a in the northern segment, 1.36–4.3 mm/a in the middle and 2.5–4.5 mm/a in the southern segment, which exhibits a spatial pattern of “higher in the south, lower in the north, with transition in the middle”. Temporal evolution suggests increased slip rates from the Late Pleistocene to Holocene. These characteristics indicate that the DLSFZ is a heterogeneous deformation system, where strain focusing on the southern segment reflects the block’s eastward escape constrained by the rigid Sichuan Basin (SB). Thus, the DLSFZ, especially its southern segment, serves as a key structure regulating crustal extrusion at the southeastern margin of the Tibetan Plateau (TP). Full article

To further improve the mechanical properties of shotcrete in coal mine roadways, end-hooked steel fibers and chopped basalt fibers were selected. Based on the optimal mix ratios identified in existing research, steel–basalt hybrid fiber shotcrete (SBFC) specimens were prepared. Dynamic impact tests under different impact loads and various hybrid fiber contents were conducted using an SHPB. The microstructure was characterized using SEM and XRD. The results show that the dynamic compressive stress–strain curve of steel–basalt hybrid fiber shotcrete can be classified as elastic deformation stage, plastic yield stage, and post-peak failure stage. The incorporation of hybrid fibers reduces the elastic deformation and plastic yield stage, and the post-peak failure stage under active confining pressure shows elastic aftereffect characteristics. The dynamic compressive strength, dynamic elastic modulus, and deformation modulus increase with the increase in impact pressure and fiber content. When there is no confining pressure, the maximum dynamic compressive strength, dynamic elastic modulus, and modulus of deformation of SBFC4 reached 53.1 ± 2.2 MPa, 4.51 ± 0.3 GPa, and 2.55 ± 0.1 GPa, respectively, representing increases of 37.20%, 264.01%, and 59.37% compared with the control group. The dynamic compressive strength increases with the average strain rate, demonstrating a favorable strain rate effect. The energy–time history curves can be roughly divided into initial, growth, and stable stages. Under the same impact load conditions, as the fiber content gradually increases, the incident energy, dissipated energy, and energy utilization rate of the specimens all show a gradual upward trend. SEM and XRD results show that steel fibers and basalt fibers maintain good bonding with the cement matrix, contribute to the formation of gel and crystalline products within the specimens, effectively delay the initiation and propagation of cracks, and thereby improve the mechanical properties of the concrete specimens. Full article

This study conducts multi-scale numerical simulations spanning atomic to macroscopic scales (i.e., from nanometer to millimeter scale) to investigate the fatigue crack propagation behavior in the welded heat-affected zone (HAZ) of AH36 shipbuilding steel. A coupled molecular dynamics–finite element method (MD-FEM) was employed to establish a multi-scale model. Through the transfer of boundary displacements, equivalent mapping of crack morphology, and crack-tip tracking, an iterative multi-scale simulation of 600 tension–tension fatigue cycles was achieved. The results indicate that the crack propagation rate is significantly influenced by crack tip morphology (blunting/sharpening) and growth direction. Notably, the peak strain at the boundary is not the sole determining factor. Periodic blunting of the crack tip occurs during cyclic loading, accompanied by a decrease in the propagation rate. Additionally, the stress field near the crack tip induces microscopic defects such as voids in the nearby area, affecting the crack propagation. This study, based on multi-scale analysis, reveals the microscopic mechanism and evolution law of fatigue crack propagation in the heat-affected zone of AH36 steel welds. Full article

Microalgae and cyanobacteria are photosynthetic microorganisms capable of removing nutrients from eutrophic waters and producing biomass. Therefore, the aim of this study was to evaluate the bioremediation performance of three microalgae and one cyanobacterium native to Lake Xochimilco and to assess their potential for biofuel production (biodiesel and biogas) from biomass generated. In photobioreactors, ammonium (96.61–97.06%), nitrate (82.4–100%), and phosphate (83.95–89.71%) were effectively removed from the lake water. The specific growth rates ranged from 0.041 to 0.144 d⁻¹ and biomass productivities from 0.016 to 0.049 g L⁻¹ d⁻¹, with high biomass yield on the substrate. The estimated CO₂ fixation rates ranged from 0.024 to 0.092 g L⁻¹ d⁻¹. Chlorella sp. achieved the highest yield of fatty acid methyl esters (FAMEs) with 91.24% of the extracted lipids. Overall, saturated FAMEs were predominant in the biodiesel; however, the presence of monounsaturated FAMEs such as methyl palmitoleate and methyl oleate enhances their fluidity and oxidative stability. Synechocystis sp. and Chlorella sp. produced the most biogas using biomass after lipid extraction, at 429.5 L kg⁻¹ VS and 404.9 L kg⁻¹ VS, respectively, with over 60% biomethane. These strains represent a sustainable and promising possibility for water bioremediation and generating biofuels. Full article

The widespread loess in western China poses significant challenges to transportation infrastructure construction due to its water sensitivity and collapsibility. This study investigates the interface mechanical properties of bamboo geogrid-reinforced loess under static loading through large-scale indoor pull-out tests and DEM–FDM coupled numerical simulations. The effects of vertical stress, the pull-out rate, the number of transverse ribs, burial depth, and reinforcement material on interface behavior were systematically evaluated. Results show that peak pull-out force increases with vertical stress, the number of transverse ribs, and burial depth, with all curves exhibiting pronounced strain hardening followed by softening characteristics. The pull-out rate exhibits a non-monotonic effect, with peak resistance higher at both lower and higher rates compared to intermediate rates. Bamboo geogrids demonstrate substantially superior performance over geogrids, with approximately four times higher peak pull-out resistance and greater initial stiffness. Numerical analysis reveals increased porosity and decreased coordination number in the grid vicinity, the horizontal stratification of the slip rate along the reinforcement, and concentration of strong force chains ahead of transverse ribs, elucidating the model-derived mechanisms underlying the macroscopic reinforcement effects. The findings confirm that bamboo geogrids provide effective and sustainable reinforcement for loess subgrades, offering a scientific basis for environmentally friendly engineering applications in loess regions. Although potential long-term durability under field environmental conditions requires further verification, the superior mechanical interface performance demonstrated here positions treated bamboo geogrids as a promising sustainable reinforcement option. Full article

Ductility dip cracking (DDC) remains a persistent challenge in multipass welds of high-chromium nickel-based alloys used in the nuclear power generation industry. While dynamic recrystallization (DRX) has been observed to arrest DDC crack growth and has been associated with weld regions that experience less DDC, there exists no quantitative relationship between the extent of recrystallization in a microstructure and DDC susceptibility. This research examines the influence of intragranular carbides on DRX behavior and establishes an experimental relationship between DDC susceptibility and extent of recrystallization in high-chromium nickel-based weld metals, novel contributions for this alloy system. In this work, the DRX behavior of the weld metal of high-chromium nickel-based filler metals (FM-52, FM-52M, FM-52i, and FM-52xl) was investigated under controlled thermo-mechanical conditions, and its effect on DDC susceptibility was established. Weld metal specimens were subjected to uniaxial deformation at 1100 °C to a true strain of 2% at strain rates of 10⁻³/s and 10⁻⁴/s using a Gleeble 3800^TM. Recrystallization was quantified using electron backscatter diffraction (EBSD) via grain orientation spread (GOS) analysis and dislocation–precipitate interactions were examined using transmission electron microscopy (TEM). Strain-to-fracture (STF) testing at 950 °C was employed to assess DDC susceptibility as a function of the extent of recrystallization and grain surface area. All tested weld metals exhibited increased recrystallization and grain refinement, as the strain rate decreased from 10⁻³/s to 10⁻⁴ s. The FM-52i weld metal specimens exhibited the highest grain refinement under high temperature deformation, followed by the FM-52xl, FM-52, and FM-52M weld metals with a percent reduction in average grain surface area of 51.22%, 41.66%, 35.48%, and 24.40%, respectively. The FM-52i weld metal specimens also exhibited the highest recrystallization response, followed by FM-52M, FM-52xl, and FM-52 weld metals at 75%, 40%, 39% and 21% recrystallized, respectively. Weld metals containing strong carbide formers experienced higher recrystallization responses than those without due to precipitate–carbide interactions. All tested weld metals experienced drastic reductions in DDC response with increasing extent of recrystallization and decreasing average grain surface areas. DRX in STF specimens was observed to facilitate uniform plastic strain accumulation, lowering overall DDC susceptibility compared to non-recrystallized specimens. Full article

This study developed a dual-antigen enzyme-linked immunosorbent assay (ELISA) based on σB protein and genotype 5-specific σC protein of avian reovirus (ARV). First, σB and σC proteins were expressed and purified using recombinant technology. Through optimization of coating conditions, the optimal antigen combination was determined to be a mixture of the two proteins at a 1:3 molecular ratio (total concentration: 0.8 μg/mL). Key parameters of the indirect ELISA were optimized via checkerboard titration. Validation confirmed that the dual-antigen ELISA exhibited a sensitivity of 1:3200 against genotype 5 ARV-positive sera, with no cross-reactivity and a coefficient of variation of 2.9–8.6%, demonstrating excellent reproducibility. In application testing, the method specifically detected serum antibodies against genotype 5 ARV variant strains, achieving a 100% positive detection rate in experimental chickens within the first week post-challenge and effectively monitoring dynamic antibody changes in infected flocks. Furthermore, the detection rate for genotype 5-positive serum samples (100%) was significantly higher than that of a commercial kit (75%). This dual-antigen indirect ELISA overcomes the sensitivity limitations associated with conventional genotype 5 ARV detection methods and provides a reliable tool for epidemiological surveillance and infection monitoring. Full article

Dementia caregiving represents a major public health challenge, with spousal caregivers assuming the greatest burden. Spouses, themselves typically older adults, provide high intensity, long-term, and largely unpaid care across all stages of cognitive decline. Despite their central role in dementia care, the health consequences experienced by spousal caregivers remain insufficiently characterized in the literature and inadequately addressed in clinical and public health practice. This structured narrative review synthesizes current evidence on the multidimensional impact of dementia caregiving on the physical, psychological, cognitive, social, and financial health of spousal caregivers. It further contextualizes these consequences within the trajectory of dementia progression, and identifies interventions, support systems, and policy considerations necessary to mitigate caregiver burden. Spousal caregivers experience disproportionate burden due to continuous, escalating responsibilities that often mirror the progressive deterioration of their partners. Emotional burdens, including uncertainty during pre-diagnostic stages, role strain, conflict, loss of intimacy, and anticipatory grief. Physically, spouses endure musculoskeletal strain, sleep disruption, poor nutrition, and heightened frailty risk. Psychologically, spousal caregivers exhibit elevated rates of depression, anxiety, loneliness, and stress-related disorders. Socially, caregivers experience substantial isolation, stigma, and erosion of social networks. Financial hardship, including early retirement, reduced employment, and uncompensated care hours, further exacerbate stress. Evidence suggests that chronic caregiving stress contributes to biological changes such as immune dysregulation, inflammation, acceleration, aging, and potential cognitive decline in caregivers themselves. Caregiver burden influences patient outcomes as evidenced by increased emergency department use, falls, and earlier institutionalization in persons with dementia whose caregiver is subjected to a high burden. Current care models rarely include routine, caregiver assessment or structured guidance following diagnosis, resulting in substantial unmet needs. Effective mitigation requires integrated, stage-sensitive interventions, including psychosocial support, caregiver education, respite services, culturally tailored programs, and digital health tools, alongside broader policy reforms to reduce financial and structural barriers. Full article

Durability of clay-based mixes is often considered a limitation for their use in modern construction projects, especially in those involving additive manufacturing techniques. This study focuses on developing sustainable extrudable cob mixes and investigating the effect of sand particle grading, curing regime and mix composition on compressive strength, flexural strength, stress–strain response, capillary water absorption, wetting-drying cycles effect, and abrasion resistance. Results showed a significant positive impact of fine-sized sand addition into the mix on the mechanical strength and durability, due to better compaction and denser final cob mixes. Extending oven curing improves the compressive and flexural strength of all mixes due to the accelerated strength development from the higher temperature exposure. Lastly, the addition of high clay content allows for improving the compressive and flexural strength at prolonged curing aging under normal air-drying conditions. These mixes also exhibit low water absorption. Conversely, results revealed that the lime content plays a crucial role in reducing surface wear, with lime-rich mixes exhibiting lower erosion rates than the other mixes. Lime-stabilized cob mixes also demonstrate improved durability under cyclic wetting and drying. Full article

Fusarium oxysporum f. sp. lycopersici (FOL) is one of the most destructive soil-borne pathogens affecting tomato production worldwide, causing substantial yield losses and persisting in soil for extended periods. The increasing regulatory restrictions on chemical fungicides and the emergence of resistant pathogen strains have intensified the search for sustainable and environmentally friendly alternatives. This systematic review synthesizes studies published between 2000 and 2025 that evaluated the antifungal efficacy of essential oils (EOs), their bioactive constituents, and EO-based nanoformulations against FOL in tomato. A total of 40 studies were included, following the PRISMA 2020 guidelines, encompassing in vitro, greenhouse, and limited field evaluations. Many EOs rich in phenolic compounds and oxygenated monoterpenes, such as thymol, carvacrol, eugenol, citral, and menthol, consistently inhibited FOL growth and spore germination, with reported mycelial growth inhibition ranging from 60 to 100% and minimum inhibitory concentrations (MICs) between 0.05 and 1.5 µL ml⁻¹. However, the use of EOs is often limited because they evaporate quickly, do not mix well with water, can harm plants, and do not persist under field conditions. Nano-delivery systems, including nanoemulsions, polymeric nanoparticles, chitosan-based carriers, and lipid-based nanostructures, have been shown to enhance the stability, bioavailability, and antifungal efficacy of EOs. This has led to improved disease management and reduced pesticide application rates. In addition, several EO-based treatments have been reported to activate plant defense responses, including the induction of defense-related genes, antioxidant enzymes, and epigenetic modifications. Overall, EO-based nanoformulations show promise as next-generation biopesticides for the sustainable management of tomato Fusarium wilt. Nevertheless, large-scale field validation, standardized formulation protocols, and regulatory assessments are required before these technologies can be widely implemented in agriculture. Full article

Polycyclic aromatic hydrocarbons (PAHs) are toxic air pollutants mainly released through vehicular emissions and can accumulate on edible plants, posing health risks to humans. This study aimed to isolate and identify endophytic fungi from Allium ampeloprasum and Brassica oleracea var. capitata, which are widely cultivated along roadside areas in the upcountry region of Sri Lanka. Sampling sites included Nuwara Eliya town, Nanu Oya, St. Clair’s, and Meepilimana (control), where above-ground parts of the selected vegetables were collected in six replicates. Fungal isolates were obtained through surface sterilization, and their ability to degrade PAHs (naphthalene, phenanthrene, anthracene, and pyrene) was evaluated using plate assays, spectrophotometric analysis, and high-performance liquid chromatography (HPLC). Phyllosphere PAH concentrations were also measured using HPLC. It revealed significantly higher concentrations of all four PAHs in the phyllosphere of both vegetables at polluted sites, with the highest levels recorded in A. ampeloprasum from Nuwara Eliya town: naphthalene (145.92 ng/g), phenanthrene (97.67 ng/g), anthracene (88.71 ng/g), and pyrene (63.82 ng/g). Most endophytic fungal strains isolated from both vegetables were able to grow on Bacto Bushnell–Haas (BBH) medium supplemented with PAHs, producing colonies exceeding 20 mm in diameter. Spectrophotometric analysis showed that Fusarium liriodendri SP2 (PV400499.1) and Trichoderma atroviride SP1 (PV400486.1) achieved approximately 75% degradation of selected PAHs. Furthermore, HPLC analysis confirmed that these isolates effectively degraded all tested PAHs, with degradation rates of approximately 70%. F. liriodendri was the most efficient degrader, achieving degradation rates of 68.50 ± 2.34% for naphthalene, 65.26 ± 1.21% for phenanthrene, 69.21 ± 1.45% for pyrene, and 66.89 ± 1.98% for anthracene. The PAH degradation byproducts of the selected fungal isolates were non-toxic to Artemia salina, confirming their environmental safety. These results highlight the bioremediation potential of endophytic fungi isolated from A. ampeloprasum and B. oleracea var. capitata in PAH-contaminated environments. Full article