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The relation of fire with the reproductive process of species from tropical grasslands and savannas has long been investigated. Post‐fire flowering is well documented in the Cerrado, but fire‐mediated fruit opening and seed dispersal has rarely been described, with very few historical records being known. Even less is known about the effects of different fire seasons on species reproduction. Here, we describe the fire‐stimulated fruit opening of Jacaranda ulei, an endemic Cerrado shrub with medical importance to traditional communities. We show that fruits opened within 2 weeks after an early dry season fire, but there were almost no viable seeds as fruits were still immature when burned. When put together with the known records for other species, dry dehiscent fruits and anemochory arise as common traits that favour fire‐mediated fruit opening. As these are common attributes in the Cerrado, it is possible that several other species also have fire‐stimulated seed dispersal but remain vastly unnoticed and underreported in the literature. Additionally, the peak reproductive effort of these species coincides with the period of prescribed burns of the Integrated Fire Management Program and, consequently, several species could also have their reproductive cycle interrupted to disperse immature seeds. We hope our note encourages further studies on the fire‐mediated fruit opening and seed dispersal of Cerrado species, particularly in relation to fire season and seed quality. [ABSTRACT FROM AUTHOR]

Fire-detection technology plays a critical role in ensuring public safety and facilitating the development of smart cities. Early fire detection is imperative to mitigate potential hazards and minimize associated losses. However, existing vision-based fire-detection methods exhibit limited generalizability and fail to adequately consider the effect of fire object size on detection accuracy. To address this issue, in this study a decoder-free fully transformer-based (DFFT) detector is used to achieve early smoke and flame detection, improving the detection performance for fires of different sizes. This method effectively captures multi-level and multi-scale fire features with rich semantic information while using two powerful encoders to maintain the accuracy of the single-feature map prediction. First, data augmentation is performed to enhance the generalizability of the model. Second, the detection-oriented transformer (DOT) backbone network is treated as a single-layer fire-feature extractor to obtain fire-related features on four scales, which are then fed into an encoder-only single-layer dense prediction module. Finally, the prediction module aggregates the multi-scale fire features into a single feature map using a scale-aggregated encoder (SAE). The prediction module then aligns the classification and regression features using a task-aligned encoder (TAE) to ensure the semantic interaction of the classification and regression predictions. Experimental results on one private dataset and one public dataset demonstrate that the adopted DFFT possesses high detection accuracy and a strong generalizability for fires of different sizes, particularly early small fires. The DFFT achieved mean average precision (mAP) values of 87.40% and 81.12% for the two datasets, outperforming other baseline models. It exhibits a better detection performance on flame objects than on smoke objects because of the prominence of flame features.

The Middle Pleistocene archaeological record of the southern Levant has proven key to understanding human evolution and intercontinental faunal biogeography. Knowledge of archaeological sites of that period in the southern Levant is biased, with most Middle Pleistocene localities in the Mediterranean areas in the north, despite the mosaic of environments that mark the entire region. A key Middle Pleistocene location in the Judean Desert – on the eastern margin of the Mediterranean zone – is the site of Oumm Qatafa, excavated in the early 1900s, which yielded a faunal collection spanning an estimated time period of 600–200 kya. Here, we present a revised taxonomy of the macromammalian fauna from the site, discuss the palaeoenvironmental implications of this assemblage, and relate the finds to other Pleistocene sites from the Levant. These data enable a more precise palaeoenvironmental reconstruction which attests to an open landscape, but with the addition of a mesic Mediterranean component close by. In addition, detailed taphonomic observations on butchery marks and Fourier transform infrared spectroscopy analysis of burnt bone link the fauna for the first time to anthropogenic activities in the cave. [ABSTRACT FROM AUTHOR]

The widespread use of renewable energy resources requires more immediate and effective fire alarms as a preventive measure. The fire is usually weak in the initial stages, which is not conducive to detection and identification. This paper validates a solution to resolve that problem by a flame detection algorithm that is more sensitive to small flames. Based on Yolov3, the parallel convolution structure of Inception is used to obtain multi-size image information. In addition, the receptive field of the convolution kernel is increased with the dilated convolution so that each convolution output contains a range of information to avoid information omission of tiny flames. The model accuracy has improved by introducing a Feature Pyramid Network in the feature extraction stage that has enhanced the feature fusion capability of the model. At the same time, a flame detection database for early fire has been established, which contains more than 30 fire scenarios and is suitable for flame detection under various challenging scenes. Experiments validate the proposed method not only improves the performance of the original algorithm but are also advantageous in comparison with other state-of-the-art object detection networks, and its false positives rate reaches 1.2% in the test set.

To maintain savanna vegetation, mid-seasonal fire has been applied since 1961 in the Lamto Savanna (Côte d'Ivoire). However, this prescribed fire has not impeded tree encroachment during recent years, nor have its effects on insect assemblages been documented. Also the impact of tree intrusion on insect assemblages is poorly studied in savanna. To prevent tree density increasing, a change in fire regime might be a solution. In this study, we examined the effect of different fire regimes (early, mid-seasonal and late fires) on leaf-litter ant assemblages in order to suggest appropriate measures for preventing tree invasion without having an effect on insect communities. Sampling was implemented by combining pitfall trapping and leaf-litter sampling before and after three different fire regimes, early, mid-seasonal and late fires. While the ant species richness declined after the passage of early and mid-seasonal fires, significantly more species were found in the burnt savanna after the late fire. However, the losses or gains of species due to different fire regimes did not cause severe changes in the ant species composition. Of the functional groups identified, only the generalists and specialist predators were respectively strongly affected by the early and mid-seasonal fires, certainly due to micro-habitat modification. Based on the trends observed in the present study, we suggest sampling other invertebrate fauna in similar savanna plots to find out if other insect groups have similar reactions to the applied fire regimes. [ABSTRACT FROM AUTHOR]

In this study, experiments were conducted on a full-scale cable interlayer experimental platform to investigate the evolution of early fires (smoldering and initial fires) in cable interlayers. Additionally, the temperature field of the fire spread and CO gas propagation characteristics were studied. The effectiveness of point-type temperature detectors, point-type smoke detectors, cable-type temperature detectors, and suction-type smoke detectors with different response time thresholds were analyzed from experiments and numerical simulation. The results revealed that the temperature fields of early fires exponentially decay in long and narrow spaces. Further, although the average propagation velocity of CO in a smoldering fire remains almost constant with increasing distance from the fire source, it decreases gradually in an initial fire. The cable-type temperature detector that remains in direct contact with the cable exhibited the shortest response time, with the non-contact detectors, including the point-type smoke detector and the suction-type smoke detector, exhibiting relatively long response times. In particular, the point-type temperature detector failed to generate a response at all in this case. Finally, the response times of fire detectors with high alarm thresholds were observed to be 10–20% higher than those of fire detectors with low thresholds. • Evolution of early fires in cable interlayers is studied. • Temperature fields of early fires decay exponentially. • Cable-type linear temperature detector has lowest response time. • Detectors with lower response thresholds perform better. [ABSTRACT FROM AUTHOR]

Abstract: The maximum rise equation was obtained by differential solution of the integral equations of a plume in linearly thermally stratified environment and its applicability in piecewise linearly stratified environment was discussed. To better understand early fire smoke movements in thermally stratified environments in large volume spaces, a detailed study of smoldering cotton wick and flaming diesel oil smoke plumes in thermally stratified environments in a small scale enclosure was investigated by experimental measurements and CFD simulations. The reasonably good agreements of the experimental results and the simulated results indicate that the thermally stratified environment intensifies the decreases of the axial temperature and velocity of a fire smoke plume until makes it stop at a maximum height. Comparisons of the maximum plume heights between the experimental measurements and the integral equation results show that the available equation underestimates the actual maximum heights of fire smoke plumes and is unable to predict the influence of smoke density upon the maximum heights. A new smoke detection method of light section image detection was suggested to overcome the shortcomings of conventional beam-type smoke sensors and detect the early fire effectively. [Copyright &y& Elsevier]

When and how humans began to control fire has been a central debate in Paleolithic archaeology for decades. Fire plays an important role in technology, social organization, subsistence, and manipulation of the environment and is widely seen as a necessary adaptation for the colonization of northern latitudes. Many researchers view purported hearths, burnt wooden implements, and heated flints from Schöningen as providing the best evidence for the control of fire in the Lower Paleolithic of Northern Europe. Here we present results of a multianalytical study of the purported hearths along with a critical examination of other possible evidence of human use or control of fire at Schöningen. We conclude that the analyzed features and artifacts present no convincing evidence for human use or control of fire. Our study also shows that a multianalytical, micro-contextual approach is the best methodology for evaluating claims of early evidence of human-controlled fire. We advise caution with macroscopic, qualitative identification of combustion features, burnt flint, and burnt wood without the application of such techniques as micromorphology, Fourier transform infrared (FTIR) spectroscopy, organic petrology, luminescence, and analysis of mineral magnetic parameters. The lack of evidence for the human control of fire at Schöningen raises the possibility that fire control was not a necessary adaptation for the human settlement of northern latitudes in the Lower Paleolithic., (Copyright © 2015 Elsevier Ltd. All rights reserved.)