Search Results (356)

An avionic weather radar antenna should be able to operate in multiple modes to cope with the change in resolution and elevation coverage as an aircraft approaches a storm cell that could expand 10 km in elevation. To solve this problem, we propose the addition of four auxiliary antenna (AuxAnt) arrays based on the phased-MIMO antenna structure to the existing avionic weather radar for future field data collection missions. Two types of signals are employed: the Type I signal transmitted by AuxAnt 1 and 2 is designed based on a non-overlapping subarray configuration, with Subarray 1 and 2 dedicated to the transmission of long and short pulses, respectively, so that the near-range blind zone is mitigated. Leveraging the waveform design and beamforming flexibility provided by the phased-MIMO antenna, pulse compressions based on frequency modulation and phase-coding are employed for wide and narrow main beams, respectively. To suppress the range sidelobes, adaptive pulse compression is used at the receiver end in substitute of the conventional matched filter. In contrast, the Type II signal transmitted by AuxAnt 3 and 4 is designed based on the contextual information so that the transmitted beampatterns have specific sidelobe levels at certain directions for interference suppression. The advantages of the proposed signaling strategy are verified with a series of ingeniously devised experiments based on real weather data. Full article

Crude oil contamination occurs frequently in soil; thus, on-site measurement of oil content is critical for controlling petroleum contamination, but it is challenging. Conventional chemical analysis requires complicated sample pretreatment and high-cost facilities, requiring on-site and cost-effective approaches. This study innovated a whole-cell bioreporter assay by combining Acinetobacter-hosted n-alkane and genotoxicity bioreporters to directly and simultaneously evaluate the contamination level and genotoxicities of crude oil in contaminated soils. Ultrasound pretreatment was employed to accelerate the measurement process, and the first-order release kinetic model was used to calculate crude oil content in an easy operation. The detection limit of the bioreporters was satisfactory at 0.1 mg/L, and the quantification range was 0.1–10 mg/L. The developed bioreporter assay effectively assessed the bioavailability and toxicity of crude oil in real contaminated soils and recognized distinct toxicities after soil weathering. Our findings highlight the feasibility of using the whole-cell bioreporter assay to evaluate the bioavailability and toxicity of crude oil, offering supporting data for the selection of remediation strategies. Full article

Recently, extreme weather has been regarded as a risk factor for exacerbating allergic airway inflammation (AAI), but its underlying mechanism remains unclear. Ferroptosis, an iron-dependent form of regulated cell death driven by lipid peroxidation, has been implicated in various lung diseases. This study investigated whether cold exposure aggravated OVA-induced AAI by promoting ferroptosis. A murine AA model was established using OVA sensitization and challenge. Mice were exposed to cold temperatures (10 °C or 4 °C) for 4 h daily. Ferroptosis was assessed by measuring ferroptosis-related markers (GPX4, ACSL4, FTL), iron deposition (Alcian Blue-Periodic Acid-Schiff Staining), lipid peroxidation (MDA), antioxidant levels (GSH), and mitochondrial ultrastructure (TEM). The ferroptosis inhibitor ferrostatin-1 (Fer-1) was administered to evaluate its protective effects. Airway inflammation, lung function, and histopathology were also analyzed. Cold exposure significantly worsened AA symptoms, including increased Th2 cytokine levels (IL-4, IL-5, IL-13, IL-33), impaired lung function, and enhanced airway remodeling and mucus production. These effects were more pronounced at 4 °C. Cold exposure also induced ferroptosis, as evidenced by decreased GPX4 and FTL, increased ACSL4, elevated iron and MDA levels, reduced GSH, and mitochondrial damage. Treatment with Fer-1 mitigated these changes, alleviating inflammation, improving lung function, and reducing histological damage. Cold exposure exacerbated AAI by inducing ferroptosis in lung tissues. Inhibition of ferroptosis with Fer-1 attenuated these aggravation effects, suggesting ferroptosis as a potential mechanistic link between cold exposure and AAI severity. Targeting ferroptosis might offer a novel therapeutic strategy for mitigating AAI under cold conditions. Full article

To quantitatively assess the storm surge induced by Super Typhoon Doksuri (2023) along the complex coastline of Fujian Province, a high-resolution Finite-Volume Coastal Ocean Model (FVCOM) was developed, driven by a refined Holland–ERA5 hybrid wind field with integrated physical corrections. The hybrid approach retains the spatiotemporal coherence of the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA5 reanalysis in the far field, while incorporating explicit inner-core adjustments for quadrant asymmetry, sea-surface-temperature dependency, and bounded decay after landfall. A series of numerical experiments were conducted, including paired tidal-only and full storm-forcing simulations, along with a systematic sensitivity ensemble in which bottom-friction parameters were perturbed and the anomalous (typhoon-related) wind component was scaled by factors ranging from 0.8 to 1.2. Static sea-level rise (SLR) scenarios (+0.3 m, +0.5 m, +1.0 m) were imposed to evaluate their influence on extreme water levels. Storm surge extremes were analyzed using a multi-scale coastal buffer framework, comparing two extreme extraction methods: element-mean followed by time-maximum, and node-maximum then assigned to elements. The model demonstrates high skill in reproducing astronomical tides (Pearson r = 0.979–0.993) and hourly water level series (Pearson r > 0.98) at key validation stations. Results indicate strong spatial heterogeneity in the sensitivity of surge levels to both bottom friction and wind intensity. While total peak water levels rise nearly linearly with SLR, the storm surge component itself exhibits a nonlinear response. The choice of extreme-extraction method significantly influences design values, with the node-based approach yielding peak values 0.8% to 4.5% higher than the cell-averaged method. These findings highlight the importance of using physically motivated adjustments to wind fields, extreme-value analysis across multiple coastal buffer scales, and uncertainty quantification in future SLR-informed coastal risk assessments. By integrating analytical, physics-based inner-core corrections with sensitivity experiments and multi-scale analysis, this study provides an enhanced framework for storm surge modeling suited to engineering and coastal management applications. Full article

Every year, thunderstorms initiating in the eastern Pyrenees cause a wide range of adverse phenomena, not only in the mountainous areas but also in the surrounding regions. Events such as heavy rainfall leading to flash floods, large or giant hail, and strong winds are common in this area. These phenomena cause significant damage and have major impacts on the population. We used remote sensing data, specifically weather radar, to identify areas that are more prone to convection initiation. This initial analysis covers the period from 2022 to 2024 and is intended to serve as the foundation for a more extensive study. The aim of this study is to characterize the diurnal convection cycle over the Pyrenees. Additionally, we plan to develop a technique that can be applied to other mountainous regions where similar data are available. The steps are as follows: (1) identifying events with precipitation over the area; (2) selecting cases associated with diurnal convection; (3) applying algorithms to determine the tracks of convective cells; and finally, (4) selecting the initial points of these trajectories. The result is a map highlighting these “hotspot” areas, which will allow us to incorporate other variables in the future, both meteorological and non-meteorological, to identify the main factors influencing the characteristics of each event. Full article

Propolis is a well-known sticky, resinous substance collected by honeybees (Apis mellifera) from the buds of trees and other plants, then mixed with beeswax and their own glandular secretions. Its chemical composition varies widely depending on the bee species, geographic location, plant sources, and weather conditions. The therapeutic potential of propolis—including antimicrobial, anti-inflammatory, and anticancer effects—has been recognized since antiquity. Cancer remains one of the leading causes of morbidity and mortality worldwide. High levels of hypoxia within tumor tissue significantly contribute to cancer progression and increase the resistance of tumor cells to radio- and chemotherapy. In the tumor microenvironment, cytokines play key roles in processes such as invasion, metastasis, and immune suppression. The concept of the “cytokine field” describes how elevated cytokine levels within the tumor microenvironment create a field effect, influencing surrounding cells. Current research is exploring the use of natural immunomodulators, such as propolis, in combination with conventional chemotherapeutic agents for cancer treatment. This review summarizes the potential immunomodulatory role of propolis within the tumor microenvironment. Full article

This study investigates a wallboard integrating encapsulated phase change materials (PCMs) within aluminum honeycomb cells to reduce building energy consumption. The thermal performance of a concrete wall enhanced with this PCM-honeycomb composite was evaluated under varying weather conditions through a two-dimensional heat transfer model. The thermal improvement of PCM is revealed in a comparative analysis of three distinct building envelope materials, i.e., concrete, concrete covered by the honeycomb wallboard, and concrete covered by the honeycomb wallboard containing PCMs. The results demonstrated that the PCM-honeycomb wallboard effectively delays and reduces peak cooling loads. The proposed system lowered building energy consumption by 28.46% and 32.12% in energy consumption over the entire summer season (and 5.76% and 6.27% over one year), respectively, compared to these reference cases. Among the tested PCMs, RT25 was identified as the most effective. The results confirm that incorporating PCM-infused honeycomb wallboards into building envelopes is a viable strategy for passive, year-round temperature regulation. Full article

Mesoscale convective systems (MCSs) play a pivotal role in the occurrence of severe weather phenomena, with convective cells constituting their fundamental elements. The precise identification of these cells from satellite imagery is crucial yet presents significant challenges, including issues related to merging errors and sensitivity to threshold parameters. This study introduces a novel detection algorithm for convective cells that leverages H-maxima transformation and incorporates multichannel data from the FY-2F satellite. The proposed method utilizes H-maxima transformation to identify seed points while maintaining the integrity of core structural features, followed by a novel neighborhood labeling method, region growing and adaptive merging criteria to effectively differentiate adjacent convective cells. The neighborhood labeling method improves the accuracy of seed clustering and avoids “over-clustering” or “under-clustering” issues of traditional neighborhood criteria. When compared to established methods such as RDT, ETITAN, and SA, the algorithm demonstrates superior performance, attaining a Probability of Detection (POD) of 0.87, a False Alarm Ratio (FAR) of 0.21, and a Critical Success Index (CSI) of 0.71. These results underscore the algorithm’s efficacy in elucidating the internal structures of convective complexes and mitigating false merging errors. Full article

Longitudinal shifts in the zonal dipole associated with the El Niño–Southern Oscillation (ENSO) in the tropical Pacific have implications for the summer climate of Southern Africa. These features are studied via Empirical Orthogonal Function analysis applied to monthly standardized sea temperatures from 1 to 100 m in depth and spanning 1980–2024. The dipole exhibits two modes: central and east Pacific. The central mode has 4–7 yr oscillations, while the east mode has a periodicity of 3 yr and 8–14 yr, with a trend toward La Niña. Correlations are mapped with environmental fields around Southern Africa. During east-mode La Niña, there are low-level westerlies over the Kalahari Plateau that coincide with a warm-west Indian Ocean and neutral summer (Dec–Mar) weather conditions over Southern Africa. The weak climatic response across the Atlantic–Indian basins during east Pacific La Niña is linked to an isolated Walker cell that feeds tropical moisture into a trough over the dateline (180° W). It is the central mode that has greater influence over Southern Africa, by triggering global Walker cells that link with the Indian Ocean Dipole. Full article

Hurricane Maria crossed Puerto Rico with winds as high as 250 km/h, resulting in widespread damages and loss of weather station data, thus limiting direct weather measurements of wind variability. Here, we identified more than 155 million trees to estimate the distribution of wind speed over 9000 km² of land from island-wide LiDAR point clouds collected before and after the hurricane. The point clouds were classified and rasterized into the canopy height model to perform individual tree identification and perform change detection analysis. Individual trees’ stem diameter at breast height were estimated using a function between delineated crown and extracted canopy height, validated using the records from Puerto Rico’s Forest Inventory 2003. The results indicate that approximately 35.7% of trees broke at the stem (below the canopy center) and 28.5% above the canopy center. Furthermore, we back-calculated the critical wind speed, or the minimum speed to cause breakage, at individual tree level this was performed by applying a mechanical model using the estimated diameter at breast height, the extrapolated breakage height, and pre-Hurricane Maria canopy height. Individual trees were then aggregated at 115 km² cells to summarize the critical wind speed distribution of each cell, based on the percentage of stem breakage. A vertical wind profile analysis was then applied to derive the hurricane wind distribution using the mean hourly wind speed 10 m above the canopy center. The estimated wind speed ranges from 250 km/h in the southeast at the landfall to 100 km/h in the southwest parts of the islands. Comparison of the modeled wind speed with the wind gust readings at the few remaining NOAA stations support the use of tree breakages to model the distribution of hurricane wind speed when ground readings are sparse. Full article

Cell towers play a key role in providing telecommunications infrastructure, especially in remote mountainous regions. This paper presents an approach to the efficient design of 42-metre-high cell towers intended to install high-power equipment in remote mountainous regions of the Carpathians (750 m above sea level). The region requires rapid deployment of many standardized towers adapted to geographical features. The main design challenges were the limited space available for the base, the impact of extreme weather conditions, and the need for a fast project implementation due to the critical importance of ensuring stable communication. Special methodological attention is given to how the transition between pyramidal and prismatic segments in cell tower shafts influences overall structural performance. The effect of this geometric boundary on structural efficiency and material usage has not been addressed in previous studies. A dedicated investigation shows that positioning the transition at a height of 33 m yields the best compromise between stiffness and weight, minimizing a generalized penalty function that accounts for both the horizontal displacement of the tower top and its total mass. Modal analysis confirms that the chosen configuration maintains a natural frequency of 1.68 Hz, ensuring a safe margin from resonance. For the final analysis of the behavior of towers with elements of different cross-sectional shapes, finite element modeling was used for a detailed numerical study of their structural and performance characteristics. This allowed us to assess the impact of geometric constraints of structures and take into account the most unfavorable combinations of static and dynamic loads. The study yields a concise rule of thumb for towers with compact foundations, namely that the pyramidal-to-prismatic transition should be placed at roughly 78–80% of the total tower height. Full article

The aim of this paper is to present a novel and comprehensive methodology for the dynamic modeling and experimental validation of a photovoltaic/thermal system. The dynamic model is divided into thermal and electrical subsystems, encompassing the photovoltaic/thermal module and the thermal energy storage. The thermal subsystem of both the photovoltaic/thermal module and the thermal energy storage is described by a one-dimensional dynamic model of heat transfer mechanisms and optical losses, while the electrical subsystem is presented as an electrical equivalent circuit of double diode solar cell. Model validation was conducted on a modern experimental photovoltaic/thermal system over an extended operational period at a five-minute resolution, with validation days classified as sunny, cloudy, or overcast based on weather conditions, thereby demonstrating an applied approach. The results demonstrate the lowest deviation values reported to date, confirmed using six quantitative indicators. The added value of the proposed methodology, not previously addressed in the literature, lies in the following contributions: (i) comprehensive modeling of the entire photovoltaic/thermal system, (ii) accurate consideration of optical losses in the photovoltaic/thermal module, and (iii) long-term experimental validation. Overall, the proposed methodology provides a reliable and efficient framework for PV/T system design, optimization, and long-term performance assessment. Full article

The carbon emission reduction mission requires a multifaceted approach, in which green hydrogen is expected to play a key role. The accelerated adoption of green hydrogen technologies is vital to this journey towards carbon neutrality by 2050. However, the energy transition involving green hydrogen requires a data-driven approach to ensure that the benefits are realised. The introduction of testing sites for green hydrogen technologies will be crucial in enabling the performance testing of various components within the green hydrogen value chain. This study involves an areal assessment of a selected test site for the installation of a grid-tied solar PV-green hydrogen-battery storage microgrid system at a factory facility in South Africa. The evaluation includes a site energy audit to determine the consumption profile and an analysis of the location’s weather pattern to assess its impact on the envisaged microgrid. Lastly, a design of the microgrid is conceptualised. A 39 kW photovoltaic system powers the microgrid, which comprises a 22 kWh battery storage system, 10 kW of electrolyser capacity, an 8 kW fuel cell, and an 800 L hydrogen storage capacity between 30 and 40 bars. Full article

Background/Objectives: Global warming and concomitant extreme weather events have markedly increased the incidence of heat stroke. Heat stroke (HS) poses a substantial threat to cerebral health by triggering neuroinflammation and accelerating neurodegenerative processes. The activation of the Nod-like receptor protein 3 (NLRP3) inflammasome for interleukin-1β (IL-1β) secretion has been implicated as a critical mechanism underlying HS-related fatalities. However, the potential role of specific dietary factors to counteract heat stroke-induced neurotoxicity remains largely underexplored. We previously reported that eicosapentaenoic acid (EPA) and urolithin A (UroA), a gut metabolite of ellagic acid, effectively suppress NLRP3 inflammasome activation against metabolic or pathogenic insults. This study aimed to assess the impact of eicosapentaenoic acid (EPA), urolithin A (UroA), and their combination on mitigating heatstroke-mediated NLRP3 inflammasome activation in microglial cells. Methods: In vitro heatstroke conditions were replicated by subjecting murine BV2 microglial cells to a high temperature (41 °C) under hypoxic conditions. To achieve nutrient loading, BV2 cells were preincubated with either EPA (50 µM) or UroA (10 µM). NLRP3 inflammasome activation was evaluated by proinflammatory gene expression, caspase-1 cleavage in cells, and IL-1β secretion to the medium. The caspase-1 activation was determined using a luciferase-based inflammasome and protease activity reporter (iGLuc) assay. Results: Exposure to high temperatures under hypoxia successfully mimicked HS conditions and promoted NLRP3 inflammasome activation in BV2 cells. Both EPA and UroA substantially attenuated the heat stroke-induced priming of proinflammatory genes. More importantly, EPA and UroA demonstrated a synergistic effect in mitigating HS-induced active caspase-1 production, leading to a dramatic decrease in IL-1β secretion. This synergistic effect between EPA and UroA was further confirmed by the iGLuc reporter assay. Conclusions: Dietary enrichment with EPA and UroA precursors may constitute an efficacious strategy for mitigating heat stroke-mediated neuroinflammation and neurodegenerative diseases. Full article

To effectively address the issues of curtailed wind and photovoltaic (PV) power caused by the high proportion of renewable energy integration and to promote the clean and low-carbon transformation of the energy system, this paper proposes a “chemical–mechanical” dual-pathway synergistic mechanism for the reversible solid oxide cell (RSOC) and flywheel energy storage system (FESS) electricity–hydrogen hybrid system. This mechanism aims to address both short-term and long-term energy storage fluctuations, thereby minimizing economic costs and curtailed wind and PV power. This synergistic mechanism is applied to regulate system operations under varying wind and PV power output and electricity–hydrogen load fluctuations across different seasons, thereby enhancing the power generation system’s ability to integrate wind and PV energy. An economic operation model is then established with the objective of minimizing the economic costs of the electricity–hydrogen hybrid system incorporating RSOC and FESS. Finally, taking a large-scale new energy industrial park in the northwest region as an example, case studies of different schemes were conducted on the MATLAB platform. Simulation results demonstrate that the reversible solid oxide cell (RSOC) system—integrated with a FESS and operating under the dual-path coordination mechanism—achieves a 14.32% reduction in wind and solar curtailment costs and a 1.16% decrease in total system costs. Furthermore, this hybrid system exhibits excellent adaptability to the dynamic fluctuations in electricity–hydrogen energy demand, which is accompanied by a 5.41% reduction in the output of gas turbine units. Notably, it also maintains strong adaptability under extreme weather conditions, with particular effectiveness in scenarios characterized by PV power shortage. Full article