Search Results (1,727)

Fresh-peeled garlic cloves are a very convenient ready-to-cook product; however, their high perishability requires packaging systems that maintain the quality of the garlic while addressing the need for more sustainable materials. This study evaluated the quality evolution of peeled garlic cloves during refrigerated storage (5 °C) in microperforated modified atmosphere packaging (MAP) systems consisting of trays sealed with egg white protein (EWP)-based films, either uncoated (EWP-U) or coated with beeswax (EWP-BW). Their performance was compared with commercial polylactic acid (PLA) and oriented polypropylene (OPP) films. The EWP-based packages generated an internal atmosphere of approximately 7% O₂ and 15% CO₂, under which peeled garlic cloves showed delayed fungal decay, reduced yeast and mold growth, and mitigated surface discoloration compared with other packaging systems, whose atmospheres remained closer to air. However, weight loss was promoted in the garlic cloves packaged with EWP-U films. The hydrophobic coating applied in EWP-BW films improved the water vapor barrier properties compared with EWP films, thus reducing the weight loss observed in the garlic cloves, but increasing fungal decay. These results suggest that an optimized packaging system should combine the lower water vapor transmission rate provided by EWP-BW films with the internal gas composition achieved in EWP-U packages. Accordingly, EWP-BW films represent a promising bio-based alternative for preserving the quality of peeled garlic cloves, provided that the effective O₂ and CO₂ transmission rates through the package are appropriately adjusted to generate a more favorable modified atmosphere. Full article

Artificial intelligence (AI) data centers are creating large, power-dense loads, often faster than transmission lines, substations, transformers, and grid interconnections can be expanded. This review assesses whether solid oxide fuel cells (SOFCs) can provide dependable on-site power during these grid delivery constraints and remain competitive after grid capacity becomes available. We critically synthesized evidence on AI electricity demand, competing power supply options, SOFC efficiency and durability, commercial deployments, environmental impacts, thermal and electrical integration, and hybrid SOFC–battery–grid systems. We also performed a screening-level levelized cost of electricity sensitivity analysis covering natural gas prices, carbon costs, stack replacement, grid electricity prices, and the avoided cost of delayed grid access. The evidence indicates that commercial SOFC systems can achieve approximately 50–60% net electrical efficiency and scale modularly from 325 kW units to a planned deployment of up to 2.45 GW. A nominal 100 MW installation would require approximately 308 such modules and at least 3600 m² of direct equipment area, excluding auxiliary systems and safety setbacks. However, multi-year durability targets of about 40,000 h, fuel and carbon price exposure, slow transient response, lifecycle methane emissions, and limited opportunities to use high temperature exhaust heat remain important constraints. The economic analysis indicates that avoided grid delay costs can justify SOFCs as bridge assets, whereas long-term retention requires competitiveness without this temporary benefit. SOFCs are therefore most suitable for sites that prioritize rapid access to firm power, modularity, reliability, and low local air pollutant emissions, rather than as a universal alternative to grid expansion. Full article

Hybrid structural materials (HSMs), such as nanoparticle-treated fabrics, have been shown to enhance acoustic and ballistic performance in multifunctional protective structures. They offer a promising means for low-frequency (<~1000 Hz) noise mitigation, which remains a critical challenge in aerospace and defense applications. The measurement and modeling of their sound transmission loss (TL) behavior using a coupled acoustic–poroelastic approach is explored in this study. A colloid-based soaking and drying process is used to impregnate nanoparticles into the fabric. Previous studies using SEM imaging have established that at low (<~20 wt.%) treatment levels, the nanoparticles agglomerate in the interstitial spaces between yarn crossover points, whereas at higher levels, they begin to coat the yarn bundle tops. TL was measured experimentally using normal-incidence impedance tube tests. Further, parameters such as static flow resistivity, porosity, flexural modulus, and density required to model the neat and treat samples as fluid-filled porous solids using the Biot–Allard model were obtained from experiments for a limited set of neat and treated cases. Static flow resistivity was measured using an air permeability tester as per ISO 9237, and a modified version of the Peirce’s cantilever beam test was used to obtain the flexural modulus for neat and treated samples. Porosity was estimated using digital image analytics. The poroelastic fabric model was implemented in finite element simulations, and the predicted TL was compared with experiments including those for uncalibrated treated cases. The model shows close alignment with measured TL at low frequencies (<~600 Hz) for all cases but deviates closer towards the theoretical mass law at higher frequencies, where flanking effects and the influence of the hierarchy of pores are expected to be dominant in experiments. Further studies are underway to incorporate such higher-order effects to improve predictions at higher frequencies. The development of this model provides a means to capture the influence of nanoparticle addition on the acoustic performance of Kevlar, enabling fast and efficient virtual design iterations. The approach helps optimize HSMs for noise mitigation in multifunctional applications for the aerospace, defense, and infrastructural sectors. Full article

Airborne viral transmission necessitates effective indoor air purification strategies. Conventional methods often face operational challenges, including potential secondary aerosolization and performance degradation under high-humidity conditions. This study evaluates a hybrid control system integrating a multi-walled carbon nanotube (MWCNT) field-emission plasma with a UV-LED/TiO₂ photocatalyst to continuously inactivate airborne bacteriophages. The system’s performance was assessed under varying applied voltages and relative humidity (RH) levels. The kinetic results demonstrated that the hybrid configuration yields a synergistic inactivation effect compared to the isolated plasma or photocatalytic treatments. Based on the kinetic enhancement, it is hypothesized that trace ozone generated by the plasma discharge serves as an electron acceptor on the UV-illuminated TiO₂ surface, thereby mitigating electron–hole recombination and enhancing the generation of hydroxyl radicals (·OH). Furthermore, the hybrid system exhibited operational resilience under high-moisture conditions, maintaining a robust active inactivation constant (k_a = 0.190 min⁻¹) at 70% RH without statistical degradation. This stability indicates that the continuous field emission effectively utilizes ambient moisture for secondary radical generation rather than being quenched by water condensation. Ultimately, this hybrid technology presents a continuous and adaptable engineering control measure for mitigating airborne pathogens in enclosed occupational environments, including those in high-humidity climates. Full article

Mammalian orthoreoviruses (MRVs) are segmented, double-stranded RNA viruses that infect a broad range of mammalian hosts, including humans. Although MRVs have been detected in wastewater in parts of Southeast Asia, they have not previously been reported in U.S. wastewater. Using the VirCapSeq-VERT pan-viral sequencing assay, we identified MRV type 2 (MRV-2) in a wastewater sample collected in March 2024 from the United States Air Force Academy. Complete genome sequences were recovered for all 10 segments. Phylogenetic analyses showed that the virus clustered most closely with an MRV isolate recovered from a big brown bat (Eptesicus fuscus) in Pennsylvania, with additional genomic similarity to a second bat-derived isolate from Nebraska. The MRV sequence signal declined rapidly in subsequent wastewater samples and was nearly undetectable two weeks later. These findings represent the first reported detection of MRV in U.S. wastewater and demonstrate the utility of pan-viral wastewater surveillance for identifying uncommon viruses with potential public health relevance. Continued genomic and epidemiologic surveillance will improve understanding of MRV circulation and zoonotic transmission in North America. Full article

Overburden rotation and mining disturbance promote deep coal fracture and spalling, potentially inducing dynamic hazards, while the coal–rock thickness ratio largely governs the composite’s dynamic response and failure severity. Based on the geological conditions of a typical deep coal mine, SHPB tests were performed on coal–sandstone composite specimens with four systematically varied coal-to-rock ratios (C:R = 1:0, 2:1, 1:1, and 1:2). High-speed photography and the digital speckle correlation method (DIC) were integrated to capture displacement, strain, energy, and fragmentation fields throughout progressive dynamic compression. Experimental data revealed four findings: (1) Crack development follows a sequential evolution process of initiation, propagation, and failure. Higher impact air pressure accelerates crack development and coalescence, resulting in a higher degree of specimen fragmentation and fewer large blocks. Within the tested range of coal–rock ratios, an increase in the rock proportion accelerates coal fracture, which is attributed to the significantly higher density and hardness of rock compared to coal. (2) Energy evolution consistently follows three stages: absorption, accumulation, and dissipation. Under identical impact pressure, a higher rock ratio elevates equivalent stiffness and wave impedance, leading to monotonic increases in peak stress, peak strain, absorbed energy, and dissipated energy. (3) The fragmentation degree exhibits a pronounced dependence on impact pressure. Specifically, for the pure coal specimen (C:R = 1:0), when the impact pressure increases from 0.3 MPa to 0.7 MPa, the mass percentage of coarse debris (>30 mm) drops from 73.37% to 18.57%, whereas that of fine particles (<4 mm) rises from 15.69% to 35.24%. (4) Under identical impact conditions, a higher rock proportion leads to increasing trends in all measured indicators, including peak stress, strain, and energy accumulation and dissipation, which are consistent with the superior mechanical properties of the rock. Based on these observations, it can be inferred that the wave impedance mismatch and stiffness ratio at the coal–rock interface play a key role in controlling stress wave transmission/reflection and strain incompatibility; however, the individual contribution of each factor warrants further dedicated investigation. Full article

Urban vegetation provides essential ecosystem services, including temperature regulation, air purification, noise reduction, and carbon storage. However, urban densification and climate-induced stresses increasingly threaten these ecosystems. Accurate classification of urban vegetation is critical for sustainable urban planning, yet remains challenging due to the structural complexity and high data density of urban LiDAR (Light Detection and Ranging) point clouds. To address current research gaps, including insufficient model interpretability, high computational demands, and limited generalization capabilities, we introduce transmissivity, a novel feature that combines echo-based LiDAR properties with spatial context to more effectively characterize urban vegetation structures. This feature enhances vegetation classification by estimating whether laser beams tend to traverse or terminate within a local neighborhood, independent of the specific return order of individual beams, thereby characterizing vegetation’s volumetric permeability. This makes transmissivity highly interpretable, unlike other echo-based statistical features. Transmissivity was evaluated alongside 52 conventional features using three different feature-importance measures across two distinct urban LiDAR datasets from Berlin and Hessigheim 3D (both datasets are from Germany). Transmissivity consistently ranked among the most influential features in both datasets across multiple scales and achieved the highest average gain (Berlin: 0.465; Hessigheim: 0.286) and the second highest mean absolute Shapley value (Berlin: 2.066; Hessigheim: 0.824). Permutation importance confirmed that transmissivity has the strongest impact on the mean decrease in F1-score (Berlin: 0.53; Hessigheim: 0.34) if used in uncorrelated feature subsets. Our findings support that echo-enriched point clouds allow efficient and accurate monitoring of urban vegetation. The feature is simple to compute and does not require additional data beyond standard multi-return LiDAR attributes. Full article

Covert communication has emerged as a promising technique for protecting wireless transmissions by concealing the existence of legitimate communication from malicious wardens. However, achieving end-to-end covert communication in space–air–ground integrated networks (SAGINs) is challenging due to the coupled effects of satellite-to-ground relay access, ground multi-hop forwarding, and cooperative jamming. In this paper, we propose an incentive-aware end-to-end covert routing framework for SAGINs, where a low Earth orbit (LEO) satellite delivers information to a ground destination through a selected relay base station and a self-organizing ground route. We first establish a two-stage SAGIN model and characterize the satellite-to-ground covert capacity under satellite sidelobe interference, as well as the ground-route covert performance in the presence of multiple wardens and cooperative jammers. Since jammers are self-interested and incur power costs when generating artificial interference, we design an incentive mechanism to stimulate cooperative jamming for enhancing ground-route covertness. Specifically, the reward allocation and jamming-power response are jointly derived by considering both the route-dependent covertness gain and the power cost of jammers. Based on the resulting route-dependent utility, the ground routing problem is further transformed into a shortest-weighted path-finding problem. To improve the long-term stability of satellite-to-ground relay access, we model the repeated interaction between the LEO satellite transmitter and the satellite warden as a base-station selection process and develop a zero-determinant strategy to stabilize the long-term expected utility relation under different warden monitoring policies. Simulation results demonstrate that the proposed framework effectively balances satellite-to-ground covert capacity and ground-route utility, outperforms baseline relay selection schemes, and achieves stable long-term covert routing performance against uncertain warden behaviors. Full article

Indoor-air research has largely examined infection, microbial ecology, immune effects and antimicrobial resistance separately, leaving the pathway from indoor biological sources to chronic respiratory outcomes insufficiently integrated. This narrative review synthesises evidence on indoor airborne pathogens and non-viable microbial components as health-relevant biological exposures beyond acute infection. Literature published between 2000 and February 2026 was reviewed from PubMed, Scopus and Web of Science, supplemented by guidance from WHO, ECDC, US EPA and ASHRAE. Viable microorganisms and non-viable components, including endotoxin, β-(1→3)-glucans, microbial DNA and extracellular vesicles, engage epithelial pattern-recognition pathways and promote inflammatory signalling. Findings included 6.5% higher TNF-α and 5% higher IL-8 per log-unit increase in fungal-spore exposure among sawmill workers; uncontrolled asthma in 45% of moisture- or mould-exposed versus 33% of non-exposed children; airborne resistance-gene and mobile-element loads of 0.55–479.44 copies/m³ in hospital departments; and a 32.8% reduction in viral diversity, but no significant reduction in high viral exposure, following classroom HEPA filtration. These findings support biological plausibility but reveal a fragmented evidence base dominated by observational studies, heterogeneous sampling and limited longitudinal exposure–response data. Indoor bioaerosols should be considered continuous exposures within the exposome, requiring research and regulation across microbiology, environmental engineering, medicine and public health. Full article

Developing sustainable and scalable personal thermal management textiles that simultaneously provide radiative cooling, moisture comfort, and responsible end-of-life management remains challenging. Here, we report a sustainable, scalable, and recyclable bamboo dissolving pulp-derived cellulose/SiO₂ fiber (CSF), fabricated by a wet-spinning process involving the dissolution and regeneration of cellulose and nano-SiO₂. The resultant CSF exhibits a hierarchical interface-pore structure, which enhances solar scattering (up to 94.56% in 0.4–1.0 μm) by Mie scattering of nano-SiO₂ particles and multiple scattering at micro- and nanopore-induced air/cellulose/SiO₂ interfaces. By coupling high mid-infrared emissivity of 94.8% (8–13 μm), the CSF demonstrates average daytime sub-ambient cooling of 9.5 °C under hot and humid summer conditions. More importantly, the CSF presents a multiscale water-transport network that integrates molecular water capture (–OH groups), capillary infiltration (nanoscale interfaces between nano-SiO₂ and cellulose), and liquid spreading and evaporation (interconnected microchannels between fibers), which realizes larger liquid diffusion area and water-vapor transmission rate (7.55 cm² and 175.48 g m⁻² 24 h⁻¹), compared to commercial cotton and polyester. In addition, the CSF demonstrates desirable soil-biodegradation capability, while the feasibility of closed-loop reuse is demonstrated through a single recycling cycle, supporting environmentally friendly wearable cooling textiles. The wet-spinning strategy paves the way for the construction of sustainable, scalable and recyclable fiber for thermal- and moisture-comfort textiles. Full article

This paper presents a sensor system for measuring the dielectric constant of materials, with a control circuit, a broadband coupler and a sensing probe as its main components. The entire system can independently measure the dielectric constant of powdered solid materials and liquid materials without relying on any auxiliary equipment. According to the transmission line design theory, the sensing probe utilizes a short-ended transmission line based on air coplanar waveguide. By introducing a parallel resistor at the input of the transmission line, material under test (MUT) with different dielectric constant can directly influence the resonance frequency of the transmission line’s reflection coefficient. The dielectric constant can be inverted through the measurement of the resonance frequency. This paper systematically analyzes the sufficient condition for the validity of the conclusion and discusses interference factors that may affect the measurement result, such as variation in resistor value and difference in material loss. Subsequently, a dedicated control circuit was designed and manufactured by integrating a control chip, an RF chip, and a detector, thus forming a low-cost, portable sensor system together with the sensing probe and coupler. Experimental tests were conducted on six different MUTs, and the results confirmed that the system has the capability to accurately characterize the dielectric constant of powdered solid and liquid material. Compared to other sensor systems, the proposed system features a simplified design and higher measurement precision, indicating its broad applicability in radio frequency identification. Full article

Biogenic volatile organic compounds released from soil (SBVOCs) are an important component of the material exchange and information transmission between terrestrial ecosystems and the atmosphere. Soil ecosystems act as both critical sources and frequently overlooked sinks of BVOCs. SBVOC emissions are mainly regulated by the temperature, moisture, and pH of the soil. Climate warming may enhance volatilization and microbial production in the short term. However, its long-term effects depend on drought, vegetation composition, substrate availability, permafrost thaw, and microbial acclimation. SBVOCs also influence microbial activity, nutrient cycling, plant–microbe interactions, plant defence, and below ground trophic interactions, although the strength of evidence differs among these functions. Ecologically, SBVOCs promote carbon cycling, modulate plant-microbe interactions, and influence atmospheric chemistry. This review further synthesizes SBVOC emission and uptake patterns across different climatic zones. Several challenges remain, particularly the scarcity of long-term quantitative measurements and difficulties in distinguishing multiple emission sources. Our understanding of rhizosphere interactions and climate-change feedback is also limited. It is essential to enhance long-term observational studies and optimize models to deepen our understanding of the role of SBVOCs in the global carbon cycle and air quality. Full article

The rapid expansion of unmanned aerial vehicles (UAVs) applications in logistics, surveillance, and defense highlights the need for scalable and reliable energy delivery solutions. Conventional charging approaches constrain operational endurance and scalability, requiring frequent returns to base. This paper presents a laser-based wireless power transmission system designed to enable safe, contactless and efficient power transfer from ground to air. The main innovation of the work lies in the integration of an end-to-end architecture combining a high-power optical source, a hierarchical beam pointing framework with coarse and fine steering stages, and a receiver composed of sensing and energy conversion module mounted onboard the UAV. A further contribution is the adoption of a hybrid control strategy in which the reference position, obtained via RTK positioning, facilitates the coarse acquisition of the beam, whilst optical feedback from the receiver side enables precise alignment corrections. An experimental campaign is conducted to validate the main system functions under representative operating conditions. Beam propagation, pointing accuracy, and control response are characterized through laboratory and outdoor tests, including long-range spot measurements and closed-loop steering validation. The results demonstrate the technical feasibility of laser-based wireless energy transfer for UAV applications and provide an experimentally grounded framework for the development of persistent aerial operations in civil and defense scenarios. Full article

This study comparatively examines the combined influence of hemp blend ratio, weft count and dual-core weft architecture on selected transport-related comfort indicators of hemp-blended denim fabrics. Eleven 3/1 twill denim fabrics were produced using two warp families, namely 100% cotton and cotton/hemp (69/31), together with rigid, single-core and dual-core weft yarns incorporating cotton, hemp, lyocell, elastane and PET/PTT T400^®. Air permeability was measured according to ASTM D737, and the water vapour transmission factor (WVPf) was determined using a wet-cup gravimetric procedure based on ASTM E96. Air permeability ranged from 96.68 to 252.96 mm/s, while mean WVPf values ranged from 102.89 to 204.28. The results indicated that weft architecture and fabric structure were more strongly associated with comfort behaviour than fibre composition alone. In particular, dual-core weft constructions generally promoted higher air permeability, whereas water vapour transmission remained dependent on a combined effect of fabric mass, sett and yarn design. Fabrics containing hemp contributed to moisture transfer performance, although the magnitude of this effect varied with constructional parameters. Multivariate evaluation further indicated that fabric mass, ends/cm and picks/cm were key variables governing the observed comfort response. Overall, the findings suggest that hemp-blended denim fabrics can be optimised through an appropriate balance of hemp content, weft count and dual-core yarn design to achieve improved breathability and moisture transport. Full article

The accessory gearbox of an aero-engine operates under high-speed and heavy-load conditions, where insufficient lubrication may lead to oil-film failure, increased frictional losses, and reduced transmission reliability. Therefore, understanding oil-jet injection and tooth surface oil-film spreading characteristics is essential for improving lubrication performance. In this study, a three-dimensional geometric model incorporating the meshing region and oil nozzles was established based on a typical accessory gear pair. The model employs the VOF multiphase flow approach and the standard k-ε turbulence model, coupled with dynamic mesh techniques to accurately capture the transient interactions between gear rotation and oil–air two-phase flow. Numerical simulations reveal the dynamic evolution of oil injection, impingement on the tooth surface, oil-film spreading, and transport into the meshing zone, while the effects of injection velocity and nozzle length on lubrication performance are quantitatively analyzed. Results indicate that an injection velocity of 45–55 m/s yields optimal oil-film coverage and uniformity, and a nozzle length of h = 30 mm minimizes jet energy decay and airflow interference, achieving uniform oil filling in the meshing zone. The optimal lubrication performance for accessory gears is obtained at an injection velocity of 45–55 m/s and a nozzle length of 30 mm. This study provides a reference for the design optimization of accessory gear lubrication systems. Full article