Abstract As tunnel construction advances in lengths and depths, the construction of tunnels in high geothermal environments has become increasingly common, raising significant fire risks. In this study, a 1:20 scale model tunnel test platform was constructed to investigate the effects of a high geothermal environment on fire behavior in tunnels during construction. The results indicate that high geothermal environments create a stratified nonisothermal flow within the tunnel, significantly impacting the burning rate and flame geometry. Under the combined effects of this special flow field and additional heat radiation from the high geothermal environment, the burning rate within the geothermal zone first decreases and subsequently increases linearly with rising geothermal temperature. Conversely, the burning rate in the nongeothermal zone initially decreases and then stabilizes. The flame tilts toward the tunnel face due to induced airflow at the base, with the tilt angle correlating directly with the geothermal temperature. A predictive formula was developed to estimate the flame tilt angle under varying geothermal temperatures. Furthermore, the flame length and height are not significantly affected by the high geothermal environment. These findings can serve as a valuable reference for future research and practical engineering applications related to high geothermal tunnels.

Dangerous fire weather is increasing under climate change, but there is limited knowledge of how this will affect fire intensity, a critical determinant of the socioecological effects of wildfire. Here, we model relationships between satellite observations of fire radiative power (FRP) and contemporaneous fire weather index, and then we project how FRP is likely to change under near-term warming scenarios. The models project widespread growth in FRP, with increases expected across 88% of fire-prone areas worldwide under 1.5 °C warming. Projected increases in FRP were highest in the Mediterranean biome and Temperate Conifer Forest biome, and increases were twice as large under 2 °C warming compared to 1.5 °C. Disaster-prone areas of the wildland-urban interface saw an average of 3.6 times greater projected increases than non-disaster-prone areas, suggesting wildfire impacts will intensify most in regions already vulnerable to dangerous wildfires. These findings emphasise the urgent need to anticipate changes to fire behaviour and proactively manage wildland-urban ecosystems to reduce future fire intensity.

Background Current fire behaviour modelling assumes that the head fire rate of spread (ROS) depends on the three factors of the classical fire environment triangle (fuel, meteorology and topography) without considering the convective processes resulting from the interaction between fire and the environment. Aims An analytical model is proposed to predict the large-amplitude oscillations of the head fire ROS caused by this interaction, which often lead to rapid acceleration and deceleration of the fire. Methods A mathematical model proposed earlier is applied to the head fire’s acceleration and deceleration phases, using results from laboratory, field-scale and wildfires, to develop the parameters. Key results Two sets of model parameters were proposed to predict the temporal variation of the ROS in the laboratory and field-scale fires. Using data from wildfires, the present model predicts the time lapses of given periods of acceleration or deceleration with sufficient accuracy. Conclusions An analytical model is proposed to predict the large amplitude temporal variation of the head fire ROS during large fires. This model will go beyond current fire behaviour models that do not explain and predict these acceleration and deceleration processes. Implications The present analytical model to predict the acceleration and deceleration of the head fire proposes a novel interpretation of the fire behaviour, considering its dynamic effects and their inclusion in fire spread modelling.

Abstract For coastal structures susceptible to corrosion, the structural fire behavior of them should be considered as a coupled damage of corrosion and high temperature. As the interfacial bond characteristics between the reinforcements and the concrete directly influence the mechanical properties of reinforced concrete structures, it is essential to release the residual bond‐slip property between corroded steel bars and concrete after exposure to high temperatures. This study examined the coupled effects of steel corrosion rates (1%, 3%, 6%, and 10%) and temperature levels (20, 100, 300, 500, and 700°C) on bond properties through center‐pullout tests on steel bar‐embedded basalt fiber reinforced concrete (BFRC) specimens. Moreover, a constitutive model was established to characterize the bond‐slip relationship between corroded steel bars and BFRC, taking temperature and corrosion rate as parameters. The results showed that at the temperatures of 100–300°C, the corrosion rate had a significant influence on the bond performance of BFRC specimens, with the severity of the effects initially increasing then continuously decreasing with the addition of corrosion rate. When above 500°C, the beneficial effect of mild corrosion vanished, exhibiting severe bond deterioration under combined thermal‐corrosion damage. The addition of basalt fibers showed limited effect on constraining the degradation of bond performance after the coupled damage. The findings of this research provide critical insights for the prediction of structural fire performance of corroded reinforced concrete structures.

Nature conservation calls for the management of reed in large stands to support the rejuvenation of reed. Traditional reed management tools at Lake Neusiedl are becoming decreasingly suitable due to insufficient freezing in winter. Therefore, prescribed burning of old Phragmites australis stands is currently being considered as a regeneration measure to promote reed regrowth and maintain invaluable habitats for specialized species in the reed belt. In January 2024 a pilot study was carried out near the municipality of Jois to gain insights into suitability and consequences of controlled burning of old reed mats in the reed belt. Applied methods include pre- and post-fire biomass and carbon content analyses from vegetation, litter and soil, fire behavior and intensity monitoring, moisture content measurements during and after the fire, and area-wide UAV-LiDAR mapping. Mean fire temperature was approx. 700 °C and peaked at 1034 °C. 15.57 ha of the 32 ha study area were affected by the fire, and a total of 57.84 tons of carbon were released (3.72 t C/ha). On burnt areas standing vegetation was removed and litter thickness significantly reduced by approx. 30%, while no biomass loss from soil was detected. Fuel moisture content is negatively correlated to distance from the water table and has mitigating effects on fire spread if above 30%, resulting in unaffected deeper layers and numerous unburnt refugia patches within the fire perimeter. Our results indicate that prescribed fire can be a suitable management tool at Lake Neusiedl for the purpose of reed rejuvenation and wetland habitat regeneration.

A halogen-free bio-based flame retardant, DBM, was synthesized from biomaterial benzaldehyde in this work. DBM was incorporated into a copolymer of cyanate ester resin and epoxy resin (EPCE), and the dielectric performance and flame retardancy of EPCE/DBM composites were explored. EPCE/10DBM containing 10 wt.% DBM, achieved a LOI value of 28.1% with a V-0 rating. In comparison to EPCE, EPCE/10DBM showed a 19.0% decrease in total heat release and a 19.1% decline in peak heat release rate. Additionally, EPCE/10DBM demonstrated both a dielectric loss of 0.00912 and a dielectric constant of 3.63, at 10 MHz. The mechanical and thermal performance of EPCE/DBM composites were also examined.

Introduction. This article presents the validation of using field fire modeling to evaluate the effectiveness of structural fire protection for cable ducts in nuclear power plant (NPP) premises.Aim. This article aims to provide computational and analytical validation of design solutions for protecting safety systems, particularly the physical separation of cable routes for different safety channels.Materials and methods. In this study, the field method was used to calculate local fire parameters within cable structures made from fire-resistant materials with a regulated fire resistance limit.Results. Based on an analysis of experimental data regarding the development of fires in enclosed cable routes, conclusions were drawn about the specifics of fire development within cable trays. Computational and analytical studies that used the field method to calculate fire dynamics expanded the scope of the research and identified typical fire parameters in cable trays made from modern, fire-resistant materials. The analytical method presented in this article was employed to validate the effectiveness of structural fire protection for cable ducts in NPP premises.Conclusions. Computational and analytical studies of fire behavior in cable ducts are important for developing design solutions for constructing, reconstructing, and making major repairs to cable systems in nuclear power plants. These studies can validate fire protection requirements for cable routes and structures during the design and construction of NPP. The results may also be used to develop or refine regulatory documents that ensure fire safety in NPPs under construction. The results are also relevant for developing design solutions for constructing, reconstructing, and making major repairs to cable systems, as well as for replacing and re-laying cable products in operating NPPs.

BackgroundIntroduction of non-native insect species and extreme wildfire events threaten terrestrial ecosystems and their services worldwide. However, the effect of invasive sap-feeding insect species outbreaks on fire severity is poorly understood, particularly regarding their effects on fire behavior and the probability of crown fire ignition. We set up two experimental designs to investigate how the alien tortoise scale Toumeyella parvicornis influenced fire behavior dynamics and canopy surface reflectance in Mediterranean Pinus pinea stands that were severely burnt in the summer of 2017. We combined Rothermel’s model for fire surface spread and Van Wagner’s crown ignition model to simulate fire behavior and employed data from the Landsat 8 collection to detect canopy wilt symptoms related to the multivoltine T. parvicornis abundance.ResultsSimulating fire behavior in single-story P. pinea thinned and unthinned stands indicated that all the predicted fires were surface fires. Uncertainty analysis of the canopy fuel attribute model inputs revealed that fires in thinned stands were entirely classified as surface fires. In contrast, only 62.7% were surface fires in unthinned stands, whereas 37.3% were categorized as conditional fire types. Among the Landsat reflectance bands, only the NIR, green, and SWIR 2 were sensitive to the abundance of T. parvicornis. Based on these sensitive bands, two-band NIR-multiplied vegetation indices were significantly associated with the abundance of T. parvicornis from the fall generation onward when sooty mold consistently covered the canopy needles.ConclusionThe divergence between observed and predicted fires in pine stands highlights the need to investigate the processes and variables linked to T. parvicornis feeding activity on P. pinea trees to enhance fire behavior prediction. Therefore, understanding how insect outbreaks can modify fire behavior in pine stands is crucial for effective management at the local and landscape levels. Identifying the vegetation index based on sensitive bands represents an essential step toward the early recognition of insect outbreaks on a large spatial scale.

It’s a high time that, the local bodies who are solely responsible for protecting human lives and public as well as government property require a paradigm shift in their approach towards tackling the disaster management especially the fire disaster. With the fast-changing scenario of advancement and development in the life style of public at large and also due to accelerating urbanization, the problem of Fire Disaster has acquired a totally new and complex dimension which has further become more complicated owing to climate change and insurge of high-rise structures. Similarly, absence of exposure to new technological advancements to local bodies supporting staff who are responsible for combating the fire cases and the decision makers, who are responsible to bring necessary developmental changes in the available resources, has brought back the status of disaster management capabilities and thus the local bodies presentlyseem to be not equipped to face the disaster effectively and efficiently. It is, therefore essential to adopt and adapt newest technologies such as Artificial Intelligence, Digital Twin Technology, Machine Learning and Internet of Things (Iot) and apply these modern technology-oriented designs and tools to support and augment the skills already possessed by the local body representatives and who are already aware of the principles of disaster management but with the coupling of the newest and modern technology their capabilities can be more sharper and advanced which is the need of the hour.This paper is an attempt to highlight this need by which the present human resource at local bodies will be able to sharpen their skills of disaster management and will be more suitably armed to tackle the fire disasters more efficiently and effectively. It is expected that by adopting to these changes where the exposure to predictive analysis and risk management, data analysis, predictive modelling, early warning system, real-time monitoring, fire behavior prediction, and anticipation besides introduction to twin technology, can bring out sea changes positively in the management capabilities of local bodies.

ABSTRACTAimEucalypt species are known for their diversity of bark types and adaptation to fire and drought. Eucalypts with stringy bark and ribboning bark are notorious for accumulating large amounts of bark fuels compared to other tree species. In this study, we examined the fire regime (fire frequency and intensity) and bioclimatic distributions of 12 contrasting eucalypt bark types, and provided maps of eucalypt bark type distributions for use in fire behaviour modelling.LocationTreed regions of New South Wales, Australia.MethodsWe used machine learning techniques to model eucalypt bark type observations recorded in 5949 vegetation census plots. We used 79 environmental variables, and a novel fire regime categorisation to model the geographical distributions of 12 eucalypt bark types.ResultsSmooth‐bark eucalypts are associated with a range of fire intensities, while eucalypts with a combination of smooth and rough bark (‘smooth with stocking’ and ‘halfbark’) are most likely to occur where fires are low intensity and rare. Smooth with stocking and halfbark eucalypts also occur more frequently in hot, dry regions than most of the rough‐barked eucalypts examined. The most hazardous bark types to fire management personnel are restricted to more productive locations, defined by high water and soil nutrient availability. They are also most likely to occur where fires tend to be frequent and medium to high intensity, likely contributing to more extreme fire behaviour.ConclusionsThese results support growing evidence for bark type being a key indicator of pyro‐ecological strategies. Our results provide partial support for the theory that trade‐offs in investment between smooth and rough bark govern the spatial distributions of the smooth with stocking and halfbark eucalypts. However, these trade‐offs do not apply universally across all eucalypt bark types. Bark types that produce large quantities of bark fuels were limited to highly productive sites. We posit that site productivity may limit the distributions of these bark types due to constraints on trunk growth rates, as trunk growth rates likely play a role in determining rates of bark fuel production.

T-type calcium channels attenuate anxiety in MPTP-treated mice through modulating burst firing of dopaminergic neuron.

Polymer materials are widely used due to their versatility; however, their vulnerability to fire is a significant concern, especially under electrical influences on engineered mechanical designs and marine structure applications. This study examines the fire resistance of a polypropylene (PP) blend using Glow-Wire Flammability Index (GWFI) and Glow-Wire Ignition Temperature (GWIT) tests. While previous research typically relies on flame-retardants to address flammability, this work proposes using a simple 1:1 weight ratio blend of two distinct PP types. This specific PP blend was selected to provide balanced material properties and improved processing consistency. The results from glow-wire tests were compared with previous findings to evaluate flammability performance. Our findings reveal that although the PP blend offers enhanced fire resistance compared to neat PP, it remains inferior to PP-containing flame-retardant additives. The outcomes suggest that this blended PP may be suitable for applications where mechanical properties, cost-effectiveness, and recyclability precede fire resistance, such as engineered automotive interiors, mechanical design of marine transportation, and low-risk electrical components in engineering infrastructure. This initial research contributes valuable insights into the fire behavior of PP blends. Moreover, it establishes a foundation for future investigations into polymer fire resistance, encouraging additional glow-wire testing on other polymer systems.

The aim of this study was to determine whether there are sex differences in motor unit firing behavior in patients with Parkinson's disease. Twenty-seven patients with Parkinson's disease (females = 14 [age = 71.1 ± 6.8], males = 13 [age = 69.2 ± 10.3], Unified Parkinson's Disease Rating Scale Part III score; females = 10.8 ± 4.8, males = 11.4 ± 1.4) performed a contraction at 30% of the maximal voluntary contraction. For each participant, motor unit spike trains were decomposed from high-density surface electromyography data recorded from bilateral vastus lateralis muscles via blind source separation algorithms. In addition to the mean discharge rates, persistent inward currents were estimated via a paired motor unit analysis. Females presented significantly greater laterality of discharge rate (p = 0.001) and persistent inward currents (p = 0.0121) than males. A significant correlation was observed between the discharge rate and the recruitment threshold on the bilateral side of males and the less-affected side of females but not on the more-affected side of females. These findings indicate that sex differences in motor unit behavior exist in Parkinson's disease patients. Motor unit behavior may be a sensitive and quantitative evaluation tool to highlight differences in disease presentation between males and females.

Fire behavior depends on meteorological variables, fuel characteristics, and topography. This study aimed to analyze the effects of meteorological and fuel variables on fire behavior during agricultural burning in Membrillal parish, Jipijapa, Manabí, Ecuador. The research followed a non-experimental, cross-sectional design. Fifteen plots (5 × 1.5 m) were established on fuel rows composed of Zea mays L. residues and weeds. Five plots were burned during each work session (morning, midday, and afternoon). Meteorological, fuel, and fire behavior variables were measured, and average values were obtained for each session. Although the experimental burns were conducted in early August (early burning period), complete combustion of the fuel was achieved. The high coefficient of determination found in the regression analysis between the dry weight of the fuel and the heat released per unit area suggests that the resulting equation could be used to adjust the burning pattern by reducing fuel weight per m²—achievable by increasing the width of fuel rows.

Predicting the characteristics of fire spread in buildings is crucial for fire safety design. This paper presents a simple model for predicting fire growth behavior of a flexible polyurethane slab in a compartment. The model consists of a fire growth model and a two-layer zone model. As for the fire growth model, six flame geometries were proposed to calculate the radiation from flame and the flame impingement on the ceiling. The smoke layer temperature and radiation interexchange were calculated by an improved two-layer zone model for smoke transport. As a result, radiation feedback to polyurethane slab was calculated in terms of internal radiation from flame and external radiation from extended flame, heated ceiling surfaces and the smoke layer. The effect of external radiation is considered to predict the increase in fire spread rate and heat release rate from the fire source. The accuracy of the model was verified by comparing calculated values with experimental values carried out by Akao et al. It was found that the fire growth behavior was well predicted when the ceiling is high, and slightly over predicted when the ceiling is low.

In this work lightweight and fire-resistant sandwich structures were fabricated and their mechanical, thermal, and fire behavior were investigated. The non-woven mat consisting of jute and polyester fibers at a ratio of 60:40 was used to manufacture Hybrid fiber reinforced Sodium silicate Composites (HSC) to be used as the core of the sandwich structure. The concentration of sodium silicate solution was varied (i.e., 80%, 90%, and 100%) to manufacture HSCs. The woven Jute fiber mat reinforced Epoxy Composites (JEC) were prepared using hand layup followed by light compression method to be used as the skins of the sandwich structures. The tensile and flexural test results revealed that HSC with 100% sodium silicate concentration showed increased strength and modulus. The thermal conductivity was not significantly affected by the sodium silicate solution concentration to prepare HSC and the thermal conductivity of the sandwiches are significantly lower than many existing jute-fiber based composites. However, the fire spread, and damage propagation during fire exposure test were significantly affected by the sodium silicate solution concentration. Sandwich with 100% sodium silicate solution concentration is found to have minimum damage due to fire exposure for 30 minutes. These findings provide a comprehensive understanding of the fabrication processes and design of the sandwich structures using HSC and JEC for applications where high strength, insulation, and fire resistance are required together.

Cable fires pose significant risks to electrical infrastructures, and cable spacing plays a crucial role in influencing fire propagation behaviors. In this study, the combustion characteristics of two parallel thermoplastic cables under varying spacing conditions were systematically investigated through controlled experiments. Key parameters, including flame merging behavior, flame morphology, mass loss rate, flame spread rate, flame temperature, and radiant heat flux, were analyzed. The results revealed that cable spacing critically affects flame interaction, with three distinct flame merging modes—continuous merging, intermittent merging, and non-merging—identified as spacing increases. A critical spacing of 2.5 mm was found, at which the flame spread rate and mass loss rate reached their maximum, approximately 1.7 times higher than that of a single cable. At intermediate spacings (2.5–12.5 mm), enhanced flame interaction and radiative feedback significantly intensified combustion, leading to higher flame temperatures and radiant heat peaks. Conversely, insufficient oxygen supply at zero spacing and reduced flame interaction at large spacings (15 mm) resulted in diminished combustion efficiency. These findings highlight the importance of cable spacing as a key design parameter for mitigating fire hazards in electrical installations, providing valuable insights for fire safety engineering and risk assessment.

Background Merging fire fronts have been associated with rapid fire spread and extremely destructive wildfires, yet few studies have characterised these behaviours outside the laboratory. Aims This study aimed to improve our understanding of merging fire fronts using two experimental harvested crop burns in Victoria, Australia, in 2021. Methods Unmanned aerial vehicles (UAVs) were used to capture the propagation of fire fronts exhibiting different merging behaviours, including forward and backward (V-shaped) junction fires, linear and coalescing fronts. Key results A fourfold increase in fire length of forward junction fires led to a doubling of the mean rate of spread (ROS). Forward junction fires spread, on average, three times faster than linear fire fronts, and they also exhibited higher temperature peaks during merging. An increase in the junction angle during merging was observed for all initial junction angles except 60°–90°, but in contrast to laboratory studies, no significant decrease in the ROS was found as the junction angle increased. Conclusions Our findings suggest that junction fires may lead to other dynamic fire behaviours (DFBs) involving pyroconvective interactions, firebrand showers, fire whirls and other effects. Implications These results demonstrate the need for further research into merging fire fronts dynamics, to improve operational fire behaviour models.

Catastrophic fire behavior in the Sierra Nevada range is increasing in tandem with worsening forest conditions related to non-Native approaches to fire ecology and climate change. Among the myriad negative human and community effects linked to thistrend, lesser understood are the relationships between differing forest management strategies and impacts to Ancestral Places or 'Esak 'Tima (Maidu and Nisenan for “places to learn”) which are living locations and traces of Ancestral practices that are integral to the health of Native Californian communities. Tribal Historic Preservation Offices, TEK specialists, and Tribal Leadership are on the front lines of government-to-government negotiations of sovereignty, especially with respect to their communities' living relationships with Ancestral Places. These are sometimes located in places managed by other institutions, agencies, and land occupiers and are most often far more than just dots on a map, but rather complex interconnected landscapes of Ancestral practices. These Tribal perspectives on guarding Ancestral Places are linked to not only the uses of Cultural Fire, or wénném sa in ecosystem restoration but also increasing aspects of the legibility and reincorporation of elements of Ancestral Places and Practices into healthy contemporary relationships with Tribal community members. These aspects of applied Traditional Ecological Knowledge and practice are highlighted in the relationships between wénném sa, Tribal archaeology, and forest management techniques our coalition is researching in California and are part of how our partnership in community-accountable archaeological research supports restorative justice. We foreground the principles of guardianship in the forest to build datasets that will support community priorities for Tribal access, food and medicine sovereignty, and intergenerational knowledge transfer. These kinds of direct action guardianship and mandated research will serve as models for co-management policies in other forests. Central to our efforts is demonstrating a model of evidence-based practice in recognition that leaders in our rapidly changing ecological reality cannot have a complete toolkit without them, especially if societies attempt to reconcile issues of racial just ice and sovereignty. Our partnership in this way connects heritage resource management to forest management and human rights policy while building community accountable research deliverables.

The almost complete eradication of fire from grasslands in North America has led to non-linear hysteretic transitions to shrub- and woodlands that the reintroduction of low-intensity fire is unable to reverse. We explore the ability of the extreme ends of variation in fire behavior to help overcome hysteretic threshold behaviors in huisache (Vachellia farnesiana) encroached grasslands. We contrasted experimental fire treatments with unburned control areas to assess the ability of extreme fires burned during drought to alter the density and structure of huisache. We found that extreme fires reduced the density of huisache by over 30% compared to control plots, both through driving huisache mortality and reducing the number of new recruits following treatments. For instance, extreme fire drove 48% huisache mortality compared to 4% in control treatments. For surviving plants, the number of stems increased but the crown area did not significantly change. Prescribed fire, conducted under the right conditions, can drive high mortality in one of the most notorious encroaching species in the southern U.S. Great Plains. With the fire conditions observed in this study likely to increase under future climate projections, utilizing extreme fire as a management tool for huisache will help scale up management to meet the growing extent of woody encroachment into grasslands.