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Radionuclides are essential for chemical and biological innovations, but their presence as toxic pollutant particles poses a significant threat to human health. To state this issue, bioremediation methodologies utilizing microorganisms have been implemented cost-effectively for removing elevated levels of heavy metals and radionuclides from the environment. The study's goal was to look into how bacteria (Bacillus cereus and Escherichia coli) and halophilic fungi (Aspergillus penicillioides, Engyodontium album, Penicillium imranianum, and Sterigmatomyces halophilus) tolerate radionuclides (Cesium, Strontium, and Uranium). The radionuclides inhibited bacteria and suppressed fungal growth. Interestingly, combinations of radionuclides with fungi were found to be more lethal against bacteria. Fungi demonstrated varying tolerance to radionuclides and exhibited efficient biosorption of radionuclides. Among the halophilic fungi, P. imranianum has shown the best performance in terms of tolerance against both bacteria and radionuclides. At the same time, S. halophilus exhibited the least ability to handle the stress conditions imposed by radionuclides. This study highlights the considerable potential for biosorption by halophilic fungi under extreme stress conditions, delivering a rate effective ecological solution for the elimination of toxic radionuclides. [ABSTRACT FROM AUTHOR]

In recent years, semantic segmentation has become a key technology for autonomous driving. However, owing to the complexity of the driving environment, many semantic segmentation networks trained with RGB images do not perform well under extreme circumstances such as smoke, strong light, and low visibility. To solve the problem above, this article chooses ResNet-152 as the backbone and constructs a novel cross-operational fusion attention module into the dual encoder-decoder model to fully integrate the features from two modal inputs of RGB and thermal infrared images. First, the dual-encoder model extracts feature information from RGB and thermal infrared modal images independently. Meanwhile, the feature fusion is implemented through the proposed cross-operational fusion attention mechanism to reduce modal conflicts and focus on more details in the encoder stage. In the decoder, to further improve segmentation performance, the up-sampling feature map and the feature map of each layer of the encoder are concatenated in stages. Then, feature extraction is performed through the convolutional layer. After five times up-sampling, the image resolution is gradually restored and the semantic segmentation is carried out at the end. The experimental results show that the mean accuracy rate and mean intersection and union on the MFNet dataset are 69.3% and 56.2%, respectively. And the inference rate is about 33 images per second when it was tested on an NVIDIA GeForce 3090Ti. It meets the basic requirements of semantic segmentation for autonomous driving in extreme environments. [ABSTRACT FROM AUTHOR]

Living in extreme environments, marine organisms face constant exposure to a range of stressors, such as high radiation levels, fluctuations in temperature, and oxidative stress. Understanding extremophile fishes is crucial because it gives us valuable insights into the biochemical, physiological, and developmental processes that govern life, by observing how they operate under natural stressors. Among the most fascinating adaptations is the existence of specialised enzymes and compounds that function as potent antioxidants, successfully counteracting reactive oxygen species' deleterious effects. In this review, we analysed the findings from several studies on Antarctic and deep-sea fish species, while highlighting the environmental stressors effects toward the antioxidant system. The antioxidant defences of the considered extremophile fishes have been extensively studied, but there is still much to learn to fully understand this complex system, while the relative research is still ongoing. Consequently, we are properly anticipating further advancements over the next few years about our understanding of crucial physiological processes that support cell survival. [ABSTRACT FROM AUTHOR]

Three new compounds, apocimycin A-C, were identified from a saltern-derived Micromonospora sp. strain FXY415, isolated from Dongshi saltern, Fujian, China. Their planar structures and relative configuration were confirmed mainly by analysis of 1D- and 2D- NMR spectra. Three compounds belong to 4,6,8-trimythyl nona-2,7-dienoic acid derivatives, apocimycin A also has a phenoxazine nucleus. Apocimycin A-C exhibited weak cytotoxic and antimicrobial activities. Our research showed again that microbial communities in extreme environments are a potential resource in looking for new and bioactive led compounds. [ABSTRACT FROM AUTHOR]

Piezochromic materials refer to a class of matters that alter their photoluminescence (PL) colors in response to the external stimuli, which exhibit promising smart applications in anti‐counterfeiting, optoelectronic memory and pressure‐sensing. However, so far, most reported piezochromic materials have been confined to organic materials or hybrid materials containing organic moieties with limited piezochromic range of less than 100 nm in visible region. Here, we achieved an intriguing piezochromism in all‐inorganic zero‐dimensional (0D) Cs3Cu2Cl5 nanocrystals (NCs) with a considerable piezochromic range of 232 nm because of their unique inorganic rigid structure. The PL energy shifted from the lowest‐energy red fluorescence (1.85 eV) to the highest‐energy blue fluorescence (2.83 eV), covering almost the entire visible wavelength range. Pressure‐modulated self‐trapped exciton emission between different energy levels of self‐trapped states within Cs3Cu2Cl5 NCs was the main reason for this piezochromism property. Note that the quenched emission, which is over five times more intense than that in the initial state, is retained under ambient conditions upon decompression. This work provides a promising pressure indicating material, particularly used in pressure stability monitoring for equipment working at extreme environments. [ABSTRACT FROM AUTHOR]

SUMMARY Photosynthetic and chemosynthetic extremophiles have evolved adaptations to thrive in challenging environments by finely adjusting their metabolic pathways through evolutionary processes. A prime adaptation target to allow autotrophy in extreme conditions is the enzyme Rubisco, which plays a central role in the conversion of inorganic to organic carbon. Here, we present an extensive compilation of Rubisco kinetic traits from a wide range of species of bacteria, archaea, algae, and plants, sorted by phylogenetic group, Rubisco type, and extremophile type. Our results show that Rubisco kinetics for the few extremophile organisms reported up to date are placed at the margins of the enzyme's natural variability. Form ID Rubisco from thermoacidophile rhodophytes and form IB Rubisco from halophile terrestrial plants exhibit higher specificity and affinity for CO2 than their non‐extremophilic counterparts, as well as higher carboxylation efficiency, whereas form ID Rubisco from psychrophile organisms possess lower affinity for O2. Additionally, form IB Rubisco from thermophile cyanobacteria shows enhanced CO2 specificity when compared to form IB non‐extremophilic cyanobacteria. Overall, these findings highlight the unique characteristics of extremophile Rubisco enzymes and provide useful clues to guide next explorations aimed at finding more efficient Rubiscos. [ABSTRACT FROM AUTHOR]

Tidal dwarf galaxies (TDGs) form in the debris of galaxy mergers, making them ideal testbeds for investigating star formation in an extreme environment. We present radio continuum EVLA observations spanning 1–2 GHz of the interacting system Arp 94, which contains the TDG J1023+1952. We detect extended radio continuum emission from the disc of the TDG's putative parent galaxy, the spiral NGC 3227. The TDG lies in front of the spiral disc, partially overlapping in projection. This challenging alignment complicates the separation of the respective contributions of radio emission from the TDG and disc. However, we show that the radio continuum appears more prominent around the TDG's location, suggesting the detection of emission from the TDG. Quantifying this argument, we derive an upper limit of 2.2 mJy for the whole TDG's emission. Our derived inband spectral index map of the system generally shows the expected behaviour of combined thermal and synchrotron radio emission in a galaxy disc, except for a region at the periphery of the disc and the TDG with a flat spectrum (spectral index |$\sim$| −0.4) unrelated to regions with high H  |$\alpha$| emission. We speculate that at this location – which coincides with the intersection of faint tidal tails – the collision of gas clouds produces shocks which re-accelerate cosmic ray electrons, and thereby enhance the radio emission. Overall, this study provides new insights about the Arp 94 system and expands the sample of TDGs studied at radio frequencies, with only two confirmed detections so far. [ABSTRACT FROM AUTHOR]

Hypersonic vehicles and aircraft engine blades face complex and harsh environments such as high heat flow density and high temperature, and they are generally narrow curved spaces, making it impossible to actually install them for testing. Thin-film heat flux sensors (HFSs) have the advantages of small size, fast response, and in-situ fabrication, but they are prone to reach thermal equilibrium and thus fail during testing. In our manuscript, an ITO–In2O3 thick film heat flux sensor (HFS) is designed, and a high-temperature heat flux test system is built to simulate the working condition of a blade subjected to heat flow impact. The simulation and test results show that the test performance of the thick-film HFS is improved by optimizing the structure and parameters. Under the condition of no water cooling, the designed HFS can realize short-time heat flux monitoring at 1450 °C and long-term stable monitoring at 1300 °C and below. With a maximum output thermopotential of 17.8 mV and an average test sensitivity of 0.035 mV/(kW/m2), the designed HFS has superior high-temperature resistance that cannot be achieved by other existing thin (thick) film HFSs. Therefore, the designed HFS has great potential for application in harsh environments such as aerospace, weaponry, and industrial metallurgy. [ABSTRACT FROM AUTHOR]

The terrestrial fauna of Antarctica consists of a limited number of species, notably insects, small crustaceans and other micro-invertebrates. Over long periods of evolutionary isolation, these organisms have developed varying degrees of tolerance to multifaceted environmental stresses. Recent molecular biogeographical research highlights the enduring persistence of much of Antarctica's current terrestrial fauna, with estimates spanning from hundreds of thousands to millions of years. Parochlus steinenii, commonly known as the Antarctic winged midge, stands out as one of the only two insect species native to Antarctica. Distributed across three biogeographic regions, southern South America and the Falkland/Malvinas Islands, sub-Antarctic South Georgia and the Maritime Antarctic South Shetland Islands, this midge raises questions about the temporal isolation of its populations and their divergence. Employing mitochondrial and nuclear genetic markers, we conducted phylogeographic and demographic analyses on 151 individuals of P. steinenii obtained across the three main biogeographic regions including the Magellanic sub-Antarctic Ecoregion (MSE) of southern South America, the sub-Antarctic Island of South Georgia (SG) and the South Shetland Islands (SSI) within the Maritime Antarctic (MA). Our data support the diversification of P. steinenii during the midPleistocene around 1.46 Mya. This period included a branching event between a clade containing only specimens from the MSE and a clade containing individuals from a broader range of locations including the SSI and SG. Based on intraspecific phylogeographic and demographic inferences, we detected strong evolutionary divergence between the three main biogeographic regions. We also detected a signal of population growth during the deglaciation process in SSI and SG, contrary to the pattern seen in the MSE. The different demographic and phylogeographic histories between the sampled biogeographic regions could result from the MA and SG experiencing a strong genetic bottleneck due to a reduction in population size during the Last Glacial Maximum, while the MSE maintained a significant effective population size. The high level of divergence detected between individuals from the MSE and the remaining biogeographic regions supports the hypothesis of a speciation process taking place in P. steinenii. [ABSTRACT FROM AUTHOR]

Energy conversion, particularly light to heat conversion, has garnered significant attention owing to its prospect in renewable energy exploitation and utilization. Most previous efforts have focused on developing organic photothermal materials for low‐temperature applications, whereas the importance of simplifying the preparation methods of photothermal materials and enhancing their maximum photothermal temperature have been less taken. Herein, we prepare an organic near‐infrared (NIR) photothermal material namely ATT by a spontaneous [2+2] cycloaddition‐cycloreversion reaction. In addition to the solution‐based method, ATT could also be readily preapred by ball milling in a high yield of 90 % in just 15 min. ATT powder exhibits a broad absorption extending beyond 2000 nm, excellent processability, and thermal stability. Remarkably, ATT powder can reach an unprecedently temperature as high as 450 °C while maintaining excellent photostability upon photoirradiation. Leveraging its extraordinary photothermal and processable properties, ATT was used in the high‐temperature applications, such as photo‐ignition, photo‐controlled metal processing and high‐temperature shape memory, all of which offer spatiotemporal control capabilities. This work provides a new approach to prepare organic photothermal materials with high temperatures, and pave the way for their applications in extreme environments. [ABSTRACT FROM AUTHOR]

Aramid nanofibers (ANFs) are a strong and heat‐resistant nanomaterial that can be isolated from commercial para‐aramid fibers, which allow a bottom‐up self‐assembly to form ordered macroscale structures like ANF films. However, the anisotropic nature of high aspect ratio ANFs is not fully exploited when fabricating ANF films for the optimal mechanical properties. In this research, direct ink writing (DIW) is applied to produce ANF‐assembled films with arbitrary shapes, and the shear‐induced alignment of ANFs can follow the printing path direction. Therefore, controlled alignment of ANFs following the computer‐programmed printing pattern is achieved by DIW, which provides a path for the application of topology and nanofiber alignment optimization in nanofiber‐assembled films. In addition, the resulting DIW ANF films exhibit outstanding Young's modulus of 8.39 GPa, tensile strength of 198 MPa, and tensile toughness of 19.4 MJ m−3 in the alignment direction, together with a wide working temperature range up to 440 °C without losing 50% of its room temperature storage modulus. Moreover, the demonstrated self‐joining ability, rollability, and lamination processability of the DIW ANF films expand their potential applications toward high‐temperature ultrathin tubes, substrates for flexible printed circuit boards, and three‐dimensional all‐ANF lightweight structural parts in extreme environments. [ABSTRACT FROM AUTHOR]

Seed-based restoration in dryland environments is commonly limited by low and sporadic rainfall, extreme temperatures, and degraded soils. These challenges are exacerbated in dryland mine restoration sites where species are seeded onto mine waste substrates due to limited availability of topsoil. Native grasses are focal dryland and mine restoration species, though the ability to deliver seeds to targeted sites presents further constraints to seed-based restoration due to complex seed morphology and site attributes. Seed enhancement technologies (SETs) may help to mitigate environmental stressors and improving seed handling. In this study, SETs which promote seedling recruitment and/or address edaphic challenges while also improving seed morphology and handling were tested in four Australian native grasses (Cymbopogon ambiguus, C. obtectus, Eulalia aurea, and Eriachne obtusa). Flash flaming or acid digestion (depending on species), extruded seed pellets with or without the addition of topsoil, and flaming or acid digestion used in combination with extruded pellets (with or without topsoil) were evaluated on topsoil and mine waste substrates. Material treated with either flash flaming or acid digestion tended to produce similar maximum emergence (week 3), final emergence (week 14), and above-ground biomass (week 14) on both topsoil and mine waste when compared to the un-enhanced ('control') treatment. Extruded pellets enhanced emergence (maximum and final) on both soil types, though had no effect on biomass. Extruded pellets containing topsoil and/or when used in combination with flash flamed or acid digested florets, provided the most significant benefits to seedling emergence, particularly on mine waste soil. However, SETs were unable to mitigate the detrimental effects of mine waste substrates on seedling biomass. This study shows promise for improving seed-based restoration in post-mine and dryland environments using SETs, though also highlights potential limitations and the importance of understanding long-term (i.e., beyond emergence) plant recruitment outcomes in SET applications. [ABSTRACT FROM AUTHOR]

Organic-rich shales from the uppermost Doushantuo Fm. (South China) record one of the most negative carbonate carbon isotopic excursions in Earth's history, known as the Shuram excursion, and contain meter to micro-size spheroids. In this study, we use Raman and energy dispersive spectroscopy to identify and describe the most common diagenetic spheroids to refine our understanding of the profound perturbations of the carbon cycle and the evolution of pore fluid chemistry imprinted in the sedimentary Precambrian record, especially in the late Ediacaran. The presence of 13C-depleted carbonate concretions or organic matter (OM) enclosed by lenticular dolomitic structures within the host shale unit suggests OM remineralisation and anaerobic oxidation, resulting in authigenic carbonate precipitation during the earliest stages of sediment diagenesis. Other mineralogical features, however, point to high levels of primary production, such as apatite bands that host spheroidal microfossils with highly fluorescent quartz and OM within abiotic concretions. These observations highlight the importance of considering co-occurring biotic and abiotic processes in explaining the formation of diagenetic spheroids in ancient sedimentary environments. From an astrobiology perspective, the interplay of biotic and abiotic processes reflects the complexity of early life systems and the environments that may exist on other terrestrial planets. Understanding the signatures of biotic and abiotic interactions in the Doushantuo Fm. is crucial for identifying potential biosignatures in extraterrestrial materials, thereby enhancing our understanding of life's universality and adaptability in diverse and extreme environments. [ABSTRACT FROM AUTHOR]

The area of permafrost worldwide accounts for approximately 20% to 25% of land area. In cold-climate regions of China, which are garnering international attention, the study of low-temperature and moisture effects on rock mass mechanical properties is of significant importance. China has a wide area of cold regions. This research can provide a foundation for China's exploration activities in such extreme environments. This paper examines the mechanical behavior of rock specimens subjected to various low temperatures and water contents through uniaxial compression tests. The analysis encompasses failure modes, stress–strain relationships, uniaxial compressive strength (UCS), and elastic modulus (EM) of these specimens. Findings reveal that at lower temperatures, the rock specimens' fracture patterns transition from compressive shear failure to cleavage failure, reflecting a shift from a plastic–elastic–plastic to a plastic–elastic response. Specifically, saturated rocks exhibit a 40.8% decrease in UCS and an 11.4% reduction in EM compared to their dry counterparts. Additionally, in cold conditions, an increased water content in rocks primarily leads to vertical cracking. Under such conditions, saturated rocks show a 52.3% decline in UCS and a 15.2% reduction in EM, relative to their dry state. [ABSTRACT FROM AUTHOR]

In fiber-reinforced components, the fiber alignment and orientation have paramount influence on the thermo-mechanical properties of the resulting composite, for both short and continuous fiber. Here we present the case of an ultra-refractory matrix intended for extreme environment applications, ZrB 2 , reinforced with 20 vol% and 50 vol% short carbon fibers. In both cases, fibers tend to align perpendicular to the uniaxial pressure applied during shaping and sintering of a pellet, although the fiber tilt across the pellet thickness is difficult to determine. Moreover, for high volume fractions of reinforcement, the spatial distribution of the fibers is heterogeneous and tends to have domains of preferential orientations. We compare the information on the fiber distribution as collected by scanning electron microscopy images, X-ray computed tomography and synchrotron X-ray refraction radiography (SXRR). The three techniques prove to be complementary. Importantly, we demonstrate that SXRR yields the most statistically significant information due to the largest field of view, yet with a sensitivity down to the nanometer, and that can be successfully applied also to heavy matrix materials, such as zirconium boride. [ABSTRACT FROM AUTHOR]

Studies of needle xylem structure (NXS) are of importance in understanding the survival, and functioning of conifers, particularly in response to environmental stressors. Herein, I review the current state-of-the-art about the NXS of genus Pinus, focusing on the xylem, tracheid, and pit structure. Genus Pinus is one of the most important and widely distributed genera of forest trees in the Northern Hemisphere. Pine species are adapted to different soil types and extreme environments imposed by elevation and latitude. They grow successfully in the boreal forest, the Mediterranean Basin, and in mountains. The importance of NXS for long-distance water transport in trees is discussed and the relationships between xylem structure and function are highlighted. Little is known about the NXS of pines, as such information was available only for 12 pine species. Moreover, current knowledge about the NXS of pines is mostly based on Pinus sylvestris L., especially regarding the effect of environmental conditions on NXS. So far, tracheid pit structure has been investigated in only one study. Although NXS is also significantly influenced by tree age, the position of needles within the crown, as well as the location of the cross-section along the longitudinal axis of the needle, a detailed needle sampling design is often missing. Hence, it is suggested to extend future studies to other pine species to explain their resistance to drought and cold. Additionally, increasing the number of studies on adult trees and distinguishing between the different types of environmental stress that a tree can face during its life cycle would be beneficial. I strongly appeal to precise description of needle sampling, which will allow us both intraspecific and interspecific comparisons. Increasing knowledge about the NXS of pines will help to better explain their resistance to environmental stress and predict their tolerance to future climate change. [ABSTRACT FROM AUTHOR]

The swimming device of archaea—the archaellum—presents asparagine (N)-linked glycans. While N-glycosylation serves numerous roles in archaea, including enabling their survival in extreme environments, how this post-translational modification contributes to cell motility remains under-explored. Here, we report the cryo-EM structure of archaellum filaments from the haloarchaeon Halobacterium salinarum, where archaellins, the building blocks of the archaellum, are N-glycosylated, and the N-glycosylation pathway is well-resolved. We further determined structures of archaellum filaments from two N-glycosylation mutant strains that generate truncated glycans and analyzed their motility. While cells from the parent strain exhibited unidirectional motility, the N-glycosylation mutant strain cells swam in ever-changing directions within a limited area. Although these mutant strain cells presented archaellum filaments that were highly similar in architecture to those of the parent strain, N-linked glycan truncation greatly affected interactions between archaellum filaments, leading to dramatic clustering of both isolated and cell-attached filaments. We propose that the N-linked tetrasaccharides decorating archaellins act as physical spacers that minimize the archaellum filament aggregation that limits cell motility. The archaellum, or archaeal 'flagellum', includes asparagine-linked glycans that are important for efficient cell motility in archaea through unclear mechanisms. Here, the authors show that glycan truncation leads to clustering of filaments and alterations in cell motility, suggesting that the glycans minimize archaellum filament aggregation that compromises cell motility. [ABSTRACT FROM AUTHOR]

The tailings dump of Barraxiutta (Sardinia, Italy) contains considerable concentrations of heavy metals and, consequently, is scarcely colonized by plants. However, wild populations of the liverwort Lunularia cruciata (L.) Dum. form dense and healthy‐looking carpets on this tailing dump. L. cruciata colonizing the tailing dump was compared with a control population growing in a pristine environment in terms of: (i) pollutant content, (ii) photochemical efficiency, and (iii) volatile secondary metabolites in thalli extracts. L. cruciata maintained optimal photosynthesis despite containing considerable amounts of soil pollutants in its thalli and had higher sesquiterpene content compared to control plants. Sesquiterpenes have a role in plant stress resistance and adaptation to adverse environments. In the present study, we propose enhanced sesquiterpenes featuring Contaminated L. cruciata as a defence strategy implemented in the post‐mining environment. [ABSTRACT FROM AUTHOR]

Limitations on energetic resources create evolutionary trade-offs, prompting us to investigate if investment in claw strength remains consistent across crustaceans living in diverse habitats. Decapod crustaceans living in deep-sea hydrothermal vents are ideal for this study due to their extreme environment. In this study, we investigated whether decapods (blind crab Austinograea sp. and the squat lobster Munidopsis lauensis) living in deep-sea hydrothermal vents prioritize investing in strong claws compared to the carapace, like coastal decapods. We analyzed exoskeleton morphology, mechanical properties, structures, and elemental composition in both the carapace and claws of four Decapoda species (two each from Brachyura and Anomura infraorders) in vent and coastal habitats. Coastal decapods had ∼4–9 times more teeth on their claw cutting edge than the vent species. Further, only the coastal species exhibited higher firmness in their claws than in their carapaces. Each infraorder controlled exoskeletal hardness differently: Brachyura changed the stacking height of the Bouligand structure, while Anomura regulated magnesium content in the exoskeleton. The vent decapods may prioritize strengthening their carapace over developing robust claws, allocating resources to adapt to the harsh conditions of deep-sea hydrothermal vents. This choice might enhance their survival in the extreme environment, where carapace strength is crucial for protecting internal organs from environmental factors, rather than relying on the powerful claws seen in coastal decapods for a competitive advantage. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs) attract attention due to their safety and high specific capacity. However, their practical applications are constrained by Zn anode corrosion, dendritic growth, and poor temperature adaptability induced by a strong hydrogen‐bond network in aqueous electrolytes. Herein, a universal strategy to design strong solvating electrolytes is proposed, in which the hydrogen‐bond network and solvation structures are reconstructed by regulating the dipolar‐dipolar and ion‐dipolar interactions simultaneously. Consequently, the hydrogen‐bond network in free water is largely weakened, and the water content in the Zn2+ solvated sheath is reduced, while the hydrogen‐bond network between solvents is strengthened, which effectively broadens the operating temperature range and suppresses Zn dendrites and corrosion. As a result, Zn anodes exhibit excellent platting/stripping efficiency with an average Coulombic Efficiency up to 99.89% after 2000 cycles at 0.5 mA cm−2, impressive cycling stability (5000 h, 0.5 mA cm−2/0.5 mA h cm−2), and a wide operating temperature range of 140 °C (−50–90 °C). Moreover, the Zn//V2O3 full cells also display enhanced temperature‐resistance, implying that the designed strong solvation electrolyte has practical application potential in extreme environments. This study suggests a promising strategy to design ideal electrolytes for high‐performance AZIBs with safety, ultralong cycling life, and satisfying temperature‐resistance. [ABSTRACT FROM AUTHOR]

In complex environments a single visible image is not good enough to perceive the environment, this paper proposes a novel dual-stream real-time detector designed for target detection in extreme environments such as nighttime and fog, which is able to efficiently utilise both visible and infrared images to achieve Fast All-Weatherenvironment sensing (FAWDet). Firstly, in order to allow the network to process information from different modalities simultaneously, this paper expands the state-of-the-art end-to-end detector YOLOv8, the backbone is expanded in parallel as a dual stream. Then, for purpose of avoid information loss in the process of network deepening, a cross-modal feature enhancement module is designed in this study, which enhances each modal feature by cross-modal attention mechanisms, thus effectively avoiding information loss and improving the detection capability of small targets. In addition, for the significant differences between modal features, this paper proposes a three-stage fusion strategy to optimise the feature integration through the fusion of spatial, channel and overall dimensions. It is worth mentioning that the cross-modal feature fusion module adopts an end-to-end training approach. Extensive experiments on two datasets validate that the proposed method achieves state-of-the-art performance in detecting small targets. The cross-modal real-time detector in this study not only demonstrates excellent stability and robust detection performance, but also provides a new solution for target detection techniques in extreme environments. [ABSTRACT FROM AUTHOR]

In this paper, we aim to honor Dr. Gabriela Castaño-Meneses for her remarkable scientific career, which has served as an enduring wellspring of inspiration for the members of the Laboratory of Arthropod Ecology in Extreme Environments. Throughout her professional journey, Dr. Castaño-Meneses has delved into the exploration of arthropod ecology and taxonomy, distinguishing herself particularly in the study of springtails, mites, and ants. Her research has traversed a broad spectrum of habitats, ranging from soil ecosystems to tree canopies, encompassing cave-dwelling and aquatic environments. Her contributions extend nationally and internationally, enriching our comprehension of ecological processes which can promote efforts in biodiversity conservation amidst the challenges posed by climate change and habitat loss. Beyond her scholarly achievements, Dr. Castaño-Meneses stands out as an emblematic reference in our lives, transcending her profound humanity throughout our tenure in her laboratory. [ABSTRACT FROM AUTHOR]

Since 1980, both the intensity and duration of summer heatwaves in the middle and high latitudes of the Northern Hemisphere have significantly increased, leading this region to become a critical area for a significant increase in the frequency of intense and long-lived extreme heatwaves. We found that stronger and more persistent high-pressure systems and lower soil moisture before the events were the main drivers of intense and long-lived extreme heatwaves in western Europe and the middle and high latitudes of North America. However, in eastern Europe and Siberia, lower cloud cover before events is also a main driver of this type of extreme heatwave, in addition to the above drivers. These factors are coupled with each other and can change heatwave intensity and duration by influencing surface radiation processes during events. Using the self-organizing map classification method, we found that 6 weather patterns with increased frequency, intensity, and duration were the main dynamic reasons leading to the increase in intense and long-lived extreme heatwaves after 1980. In addition, the decrease in summer average soil moisture in most areas of the mid-high latitudes of the Northern Hemisphere and the decrease in average cloud cover in eastern Europe and Siberia are found to be the main thermodynamic reasons leading to the increase in these extreme heatwaves. [ABSTRACT FROM AUTHOR]

C. tetracocca are local characteristic plants with significant medicinal and economic values. However, little is known about the relationship of soil nutrient contents and the accumulation of primary and secondary metabolites from C. tetracocca. The metabolic accumulation of C. tetracocca grown in karst areas and non karst areas have not been compared. In this study, we sampled soil and leaves of C. tetracocca in karst areas and non karst areas to compare the relationship between soil nutrients (soil organic carbon, total nitrogen, total phosphorus, total potassium, calcium, magnesium) and organic components (organic carbon, total nitrogen, total phosphorus, total potassium, calcium, magnesium), free amino acids, functional components (catechin (C), caffeine (CAFF), gallic acid (GA), epicatechin (EC), (-)-epicatechin gallate (ECG), (-)-epigallocatechin (EGC), and epigallocatechin gallate (EGCG)) of C. tetracocca. The results showed that there was a significant positive correlation between K and EC in soil and plants and a significant negative correlation between P and EC. There was a negative correlation between Mg and EGC in soil and plants. Therefore, increasing the content of K and reducing the content of Mg and P can improve the functional components of C. tetracocca. The C. tetracocca in karst areas and non karst areas share excellent quality and have not been severely affected by the harsh environment. Therefore, these findings emphasized the significance of ancient tea trees and laid a solid foundation for the promotion and planting of C. tetracocca. [ABSTRACT FROM AUTHOR]

This study reveals a new acclimation mechanism of the eukaryotic unicellular green alga Chlorella vulgaris in terms of the effect of varying atmospheric pressures on the structure and function of its photosynthetic apparatus using fluorescence induction measurements (JIP-test). The results indicate that low (400 mbar) and extreme low (<10 mbar) atmospheric pressure decreases the density and thus increases the fluidity of the thylakoid membrane, possibly facilitating plastoquinone (PQ) movement within the membrane and resulting in enhanced photosynthetic electron flow and photochemical quenching. Molecular dynamic simulations of different light harvesting complexes within thylakoid membrane models confirm this mechanism and reveal the associated atomic scale details. The exposure of microalga to an extremely low pressure (<10 mbar) in a 100% CO2 atmosphere (simulating the Mars atmosphere), reveals that the impact of extremely low atmospheric pressure on PQ mobility within the photosynthetic membrane, coupled with the low density of an almost 100% CO2 Mars-like atmosphere, results to a similar photosynthetic efficiency to that on Earth. These findings pave the way for the identification of novel functional acclimation mechanisms of microalgae to extreme environments that are vastly distinct from those found on Earth. This study reveals a new acclimation mechanism of microalgae in low atmospheric pressure. Experimental results and molecular dynamic simulations indicate that low atmospheric pressure reduces the density and enhances the fluidity of photosynthetic thylakoid membranes, leading to enhanced photochemical quenching. Particularly, extremely low pressure (<10 mbar) in a 100% CO2 atmosphere (Mars-like atmosphere) yields a photosynthetic efficiency comparable to that of Earth, shedding light on new astrobiological perspectives. [ABSTRACT FROM AUTHOR]

Aramid nanofibers (ANFs) exhibit desirable lightweight and excellent properties, while their strength has to be sacrificed to further improve their electrical insulation and fire resistance so as to meet the special demands of extreme environments. Herein, Zylon nanofibers (ZNFs) with analogous structure compatibility but superior performance are employed to construct an assembled dual‐network structure to improve the overall properties of ANFs. A facile in situ structure restoration (ISSR) strategy is proposed to achieve ZNF aqueous dispersion for the first time by deprotonation of ZNFs, which significantly avoids the corrosive acid system and facilitates the papermaking process. The composite ANF@ZNF nanopaper exhibits incredible tensile strength (233 MPa) and toughness (14.7 MJ m−3), increased by 108% and 584% compared with pure ANF nanopaper due to the dense entangled dual‐network and tremendous hydrogen bonds. Moreover, it presents superior breakdown strength of ≈128 kV mm−1, which is 6 times higher than that of commercial Nomex T410 insulation paper with a thickness of 50 µm. Besides, it exhibits surprising flame resistance (endure 1000 °C burning) ascribed to the excellent thermostability of ZNFs. This work provides promising possibilities for expanding the applications of aramid‐based composites for advanced electrical insulation and thermal protection in extremely harsh conditions. [ABSTRACT FROM AUTHOR]

Faced with the rapid development of large-scale pumped-storage power stations, the trade-off between the strength and toughness of hydropower steels in extreme environments has been limiting their application. The effects of Nb micro-alloying and direct quenching and tempering processes on the strengthening–toughening mechanism of 1000 MPa grade high-strength hydropower steel are studied in this paper, and the precipitation behavior of Nb is discussed. The results showed that only the 0.025Nb steel using the DQT process achieved a cryogenic impact energy of more than 100 J at −60 °C. Under the DQT process, a large number of deformation bands and dislocations were retained, refining the prior austenite grains and providing more nucleation sites for the precipitation of NbC during the cooling process. The DQT process has a more obvious local strain concentration, mainly focusing on the refined lath boundary, which indicates that the refinement of the microstructure also promotes the stacking of dislocations. The improvement in fine grain strengthening and dislocation strengthening by the DQT process jointly led to an increase in strength, resulting in a better combination of strength and toughness. [ABSTRACT FROM AUTHOR]

Most user-collaborative location privacy protection mechanisms assume that collaborative group members are trustworthy and can strictly enforce collaboration rules. Such assumptions do not match reality and reduce the usability of the schemes. In this paper, we propose Invisible Man, a blockchain-enabled framework for peer-to-peer collaborative privacy games for location-based services. The framework enables users to protect their privacy in extreme environments and allows members of a collaborative group without trust to collaborate efficiently. To defend against inference attacks, a user-collaborative privacy game model is constructed, and a dual-verification mechanism with Chainlink and Witnet oracles is developed to provide security guarantees for model generation. Members can conduct cooperative games under the guidance of the model. To realize secure and efficient in-group collaboration, a blockchain-based reward and punishment mechanism for collaboration is designed, integrating token incentives and a blacklisting mechanism to ensure the verifiability and audibility of user behaviors. Security analysis and extensive simulation results demonstrate that the proposed scheme achieves high security and privacy with low costs. [ABSTRACT FROM AUTHOR]

Satellite-based precipitation estimates are a critical source of information for understanding and predicting hydrological processes at regional or global scales. Given the potential variability in the accuracy and reliability of these estimates, comprehensive performance assessments are essential before their application in specific hydrological contexts. In this study, six satellite-based precipitation products (SPPs), namely, CHIRPS, CMORPH, GSMaP, IMERG, MSWEP, and PERSIANN, were evaluated for their utility in hydrological modeling, specifically in simulating streamflow using the Variable Infiltration Capacity (VIC) model. The performance of the VIC model under varying flow conditions and timescales was assessed using statistical indicators, viz., R2, KGE, PBias, RMSE, and RSR. The findings of the study demonstrate the effectiveness of VIC model in simulating hydrological components and its applicability in evaluating the accuracy and reliability of SPPs. The SPPs were shown to be valuable for streamflow simulation at monthly and daily timescales, as confirmed by various performance measures. Moreover, the performance of SPPs for simulating extreme flow events (streamflow above 75%, 90%, and 95%) using the VIC model was assessed and a significant decrease in the performance was observed for high-flow events. Comparative analysis revealed the superiority of IMERG and CMORPH for streamflow simulation at daily timescale and high-flow conditions. In contrast, the performances of CHIRPS and PERSIANN were found to be poor. This study highlights the importance of thoroughly assessing the SPPs in modeling diverse flow conditions. [ABSTRACT FROM AUTHOR]

Galdieria sulphuraria is a thermo-acidophilic microalga belonging to the Cyanidiophyceae (Rhodophyta) class. It thrives in extreme environments, such as geothermal sulphuric springs, with low pH, high temperatures, and high salinity. This microalga utilises various growth modes, including autotrophic, heterotrophic, and mixotrophic, enabling it to exploit diverse organic carbon sources. Remarkably, G. sulphuraria survives and produces a range of bioactive compounds in these harsh conditions. Moreover, it plays a significant role in environmental remediation by removing nutrients, pathogens, and heavy metals from various wastewater sources. It can also recover rare earth elements from mining wastewater and electronic waste. This review article explores the diverse applications and significant contributions of G. sulphuraria. [ABSTRACT FROM AUTHOR]

The sea bottom acts as a key natural archive where the memory of long-term timescale environmental changes is recorded. This study discusses some ecological and chemical features of fjord sediments that were explored during the AREX cruise carried out in the Svalbard archipelago in the summer of 2021. The activity rates of the enzymes leucine aminopeptidase (LAP), beta-glucosidase (GLU), and alkaline phosphatase (AP) and community-level physiological profiles (CLPPs) were studied with the aim of determining the functional diversity of the benthic microbial community, while bacterial isolates were screened for their susceptibility to antibiotics in order to explore the role of these extreme environments as potential reservoirs of antibiotic resistance. Enzyme activity rates were obtained using fluorogenic substrates, and CLPPs were obtained using Biolog Ecoplates; antibiotic susceptibility assays were performed through the standard disk diffusion method. Spatial trends observed in the functional profiles of the microbial community suggested variability in the microbial community's composition, presumably related to the patchy distribution of organic substrates. Complex carbon sources, carbohydrates, and amino acids were the organic polymers preferentially metabolized by the microbial community. Multi-resistance to enrofloxacin and tetracycline was detected in all of the examined samples, stressing the role of sediments as a potential reservoir of chemical wastes ascribable to antibiotic residuals. This study provides new insights on the health status of fjord sediments of West Spitsbergen, applying a dual ecological and biochemical approach. Microbial communities in the fjord sediments showed globally a good functional diversity, suggesting their versatility to rapidly react to changing conditions. The lack of significant diversification among the three studied areas suggests that microbial variables alone cannot be suitable descriptors of sediment health, and that additional measures (i.e., physical–chemical characteristics) should be taken to better define environmental status. [ABSTRACT FROM AUTHOR]

Extreme precipitation events in small alpine catchments trigger hazardous hydro‐geomorphic processes that cause considerable damage to settlements and infrastructure. In summer 2011 and 2017, two flood events mobilizing large amounts of sediments struck the town of Oberwölz (Styria, Austria) located at the outlet of the Schöttlbach catchment. We used data from local weather stations and precipitation radar to analyse the meteorological settings that caused the flooding. We compiled a consistent sediment budget for the 2017 event by combining geomorphic mapping, connectivity analysis, high‐resolution airborne LiDAR (ALS) and uncrewed aerial vehicle (UAV)‐borne LiDAR (ULS), data from other authors for the 2011 event and external information (e.g., event analysis and excavation data). The 2017 event mobilized higher sediment volumes than the 2011 event (131 000 m3 vs 90 000 m3) even though 24‐h precipitation and peak discharges were lower in 2017. First assumptions that the larger sediment output was caused by the reworking of the 2011 flood deposits proved to be incorrect. The impacts of the 2011 event affected the resilience of the geomorphic system resulting in a significantly higher hillslope sediment supply. We conclude that sediment transport in alpine catchments can increase disproportionately when recurrence intervals fall below a critical level. [ABSTRACT FROM AUTHOR]

Elucidating the mechanism of soil erosion caused by extreme rainstorms could improve agroecosystems' resilience to the extreme climate. However, less attention has been paid to the regional difference of soil erosion during extreme rainstorms through multiple field investigations. Using six field surveys of extreme rainstorms, soil erosion and its driving mechanism were investigated on farmland in the Loess area and the Rocky mountain area. Conclusions are as follows: (1) Farmland was severely eroded in comparison with abandoned land and forest–grass land. The erosion modulus of farmland in the Loess area (51 606.51 t/km2) was greater than that in the Rocky mountain area (2582.75 t/km2). (2) In both the Loess area and the Rocky mountain area, the main erosion types on sloped cropland and terraced land were rills/gullies and embankment failure, respectively. Terracing is an appropriate measure that can effectively control farmland erosion in rainstorm events. (3) Concentrated flow is a major driver of soil erosion, with nearly all rills/gullies occurring in the flow paths. Drainage measures can prevent the formation of concentrated flow, weakening rills/gullies erosion in farmland. (4) Building bio‐embankment, planting high‐coverage crops, and implementing local protection measures could reduce the farmland erosion influenced by extremely heavy rainfall. Combining drainage and agronomic measures is the common strategy to combat extreme rainstorm events for reducing farmland erosion in the two regions. These results can be applied to improve the ability of agricultural systems to cope with extreme rainstorms. [ABSTRACT FROM AUTHOR]

The extreme environment of winter sports significantly impacts the performance of athletes, leading to a need for clothing that meets composite functional requirements such as warmth, comfort, and protection to improve competition performance. Knitted fabrics for ice and snow sports with excellent heat and moisture performance were inspired by the water collection and transmission system used by the Moloch horridus. A bionic design model of multi-state fabric morphology was developed by using a topological derivation method and three-dimensional parametric surface modeling technology. The experimental results showed that the four single-sided three-dimensional fabrics have better moisture management characteristics and it is possible to achieve an excellent thermal insulation performance. The textile design application models based on this new design method can provide a feasible solution for developing high-performance textiles for winter sports. [ABSTRACT FROM AUTHOR]

Accurate estimation of extreme discharges in rivers, such as the Meuse, is crucial for effective flood risk assessment. However, hydrological models that estimate such discharges often lack transparency regarding the uncertainty in their predictions. This was evidenced by the devastating flood that occurred in July 2021, which was not captured by the existing model for estimating design discharges. This article proposes an approach to obtain uncertainty estimates for extremes with structured expert judgment using the classical model (CM). A simple statistical model was developed for the river basin, consisting of correlated generalized extreme value (GEV) distributions for discharges from upstream tributaries. The model was fitted to seven experts' estimates and historical measurements using Bayesian inference. Results were fitted only to the measurements were solely informative for more frequent events, while fitting only to the expert estimates reduced uncertainty solely for extremes. Combining both historical observations and estimates of extremes provided the most plausible results. The classical model reduced the uncertainty by appointing the most weight to the two most accurate experts, based on their estimates of less extreme discharges. The study demonstrates that with the presented Bayesian approach that combines historical data and expert-informed priors, a group of hydrological experts can provide plausible estimates for discharges and potentially also other (hydrological) extremes with relatively manageable effort. [ABSTRACT FROM AUTHOR]

Six distinct COI mitochondrial Haplotype Groups (HG) are morphologically, ecologically, and genetically characterized from the aquatic nematode family Tobrilidae. Collection locations included the extreme habitats of the Alkaline Lakes in the western Nebraska Sandhills and the contaminated stream, Johnson Creek, bordering the AltEn 2021 catastrophic pesticide release near the village of Mead in eastern Nebraska. Maximum likelihood and genetic distance metrics supported the genetic integrity of the haplotype groups. Discriminant function analysis of COI haplotype group datasets of combined morphological characters and soil chemistry attributes for both male and female Tobrilidae were classified correctly in all but one case. Scanning electron microscopy revealed new details about amphid apertures, male supplements, and spicules. Partial 18S gene phylogeny suggests that the genus Semitobrilus may not be a member of the subfamily Neotobrilinae, and three specimens in the 226 tobrilid dataset provide evidence of incongruence between COI and 18S derived phylogenies. Given the strong signal provided by the environmental chemistry data, tobrilid mitochondrial haplotypes may well have value as environmental indicators.

Carabid beetles are one of the several taxa useful as model organisms to study and monitor current ecosystems features, as well as environmental changes caused by global changes. Open data about these organisms are scarcely available. To fill this gap, a data table (Darwin Core formatted) was uploaded in GBIF database (https://doi.org/10.15468/rzmp6n). The dataset is the result of a pitfall trapping survey of carabid beetles living along an altitudinal bioclimatic gradient, in the Dolomites mountains within the protected area of the Regional Park "Paneveggio e Pale di S. Martino" (Trento, Italy). Investigated environments ranged from spruce forests to the extreme environments of high altitude, so to collect a dataset as complete as possible on carabid beetles harboured in this area.The dataset included here is part of an initiative aimed at promoting the adoption of a formal structure for datasets on carabid beetles acquired by field surveys and to give open access to these data. This dataset gives the opportunity to test the effects of global change affecting the same area, within long-term surveys on carabid beetles. Furthermore, the availability of open data is intended to promote an ethical approach to ecological research under a social and scientific point of view, the first because it will avoid wasting public funds on repeating the same researches and the second because it will avoid recapturing new organisms in the same (or similar) environments by other researchers.

The emerging class of multi-principal element alloy (MPEA) processes superior mechanical properties and has great potential for applications in extreme environments. In this work, the synergic effect of the Cr content and crystallographic orientation on the deformation behaviors of single-crystal CrCoFeNi MPEAs has been investigated by atomistic simulations. We have found distinct differences in dislocation activities, deformation microstructures, and mechanical behaviors in the model MPEAs, which depend on crystallographic orientations, Cr concentration, and the number of activated slip systems. When multiple slip systems are triggered along [100] and [111] orientations, Shockley partial activation and their interaction are predominant, leading to the formation of sessile dislocations and a dense dislocation network. When only two slip systems of Shockley partials are favored along the [110] direction, the influence of Cr concentration and planner defect energies emerges. At low Cr concentration, the double planar slip of Shockley partials results in deformation-induced nanotwins. At high Cr concentration, the partial dislocations of a single slip plane become dominant, attaining the highest volume fraction of deformation-induced phase transformation. The results provide a fundamental understanding of deformation mechanisms in MPEAs, elucidating the synergic effect of crystal orientation and composition on tunning the mechanical behaviors. [ABSTRACT FROM AUTHOR]

Data-driven machine learning techniques can be useful for the rapid evaluation of material properties in extreme environments, particularly in cases where direct access to the materials is not possible. Such problems occur in high-throughput material screening and material design approaches where many candidates may not be amenable to direct experimental examination. In this paper, we perform an exhaustive examination of the applicability of machine learning for the estimation of isothermal shock compression properties, specifically the shock Hugoniot, for diverse material systems. A comprehensive analysis is conducted where effects of scarce data, variances in source data, feature choices, and model choices are systematically explored. New modeling strategies are introduced based on feature engineering, including a feature augmentation approach, to mitigate the effects of scarce data. The findings show significant promise of machine learning techniques for design and discovery of materials suited for shock compression applications. [ABSTRACT FROM AUTHOR]

Aerospace vehicles that undergo atmospheric re-entry require thermal protection systems (TPS) to protect them from the extreme environment. Currently, TPS production relies on hand layup techniques which are time-, cost-, and energy-intensive. A method to produce composite TPS via additive manufacturing (AM) is demonstrated, which uses a customdesigned formulation. Thermal characterization of the composite system showed that char yield values were comparable to ablative systems presently used in TPS. Printability was demonstrated by in situ deposition onto a rotating/tilting aluminum substrate. A five-axis printer system was developed/adapted to accommodate the contours of TPS substrates and to enable the extrudate to completely cover leading edges of vehicle control surfaces. [ABSTRACT FROM AUTHOR]

Layered MAX phases possess distinctive chemical, physical, electrical, and mechanical properties due to their amalgamation of metallic and ceramic characteristics. Understanding the corrosion mechanisms of MAX phases in various extreme environments is crucial. This paper commenced by scrutinizing synthesis techniques for MAX phase powders, thin films, and bulk materials, with a focus on fabrication processes and formation mechanisms. Subsequently, it delved into corrosion & oxidation mechanisms in diverse environments, emphasized their unique self-healing properties, and outlined future research directions. This comprehensive and systematic review aims to furnish researchers with effective guidance for selecting MAX phases based on different application environments. [ABSTRACT FROM AUTHOR]

A two-dimensional porous g-C 3 N 4 /MXene heterostructure (CN-MX) with intrinsic defects was designed as the desolvation promoter to accelerate the dissociation of solvated Li+ and propel the sulfur redox conversion. The Li-S cells with g-C 3 N 4 /MXene heterostructure demonstrated satisfactory areal capacity (5.5 mAh cm−2 at 0.2 C) and impressive low-temperature performance at 0 °C (91.6% capacity retention after 100 cycles at 0.5 C). [Display omitted] Lithium-sulfur (Li-S) batteries exhibit superior theoretical capacity and energy density but are still hindered by the sluggish redox conversion kinetic of lithium polysulfides arising from the significant desolvation barrier, especially under high current density or low-temperature environments. Herein, a two-dimensional (2D) porous graphitic phase carbon nitride/MXene (CN-MX) heterostructure with intrinsic defects was designed via electrostatic adherence and in-situ thermal polycondensation. In the design, the defect-rich CN with abundant catalytic activity and porous structure could efficiently facilitate the lithium polysulfides capture, the dissociation of solvated lithium-ion (Li+), and fast Li+ diffusion. Concurrently, 2D MXene nanosheets with high electronic conductivity could act as charge transport channels and provide electrochemical active sites for sulfur redox reactions. The Li-S cells with CN-MX heterostructure modified separator demonstrated uncommon rate performance (945 mAh/g at 4.0 C) and satisfactory areal capacity (5.5 mAh cm−2 at 0.2 C). Most remarkably, even at 0 °C, the assembled Li-S batteries performed favorable cycle stability (91.6% capacity retention after 100 cycles at 0.5 C) and outstanding rate performance (695 mAh/g at 2.0 C), and superior high loading performance (5.1 mAh cm−2 at 0.1 C). This work offers exciting new insights to enable Li-S batteries to operate in extreme environments. [ABSTRACT FROM AUTHOR]

The first Arctic explorers underwent no formal selection procedure, and their personality traits were not diagnosed. Today, select in and select out procedures in systematic screening activities are common, although each country manages a polar station recruits according to its standards. The main goal of this article is to present the results of personality tests of work candidates at the Polish Polar Station Hornsund in Spitsbergen in 2019–2023. The applicants’ personality was diagnosed with the NEO Five-Factor Inventory examining the Big Five personality traits. Results indicated that candidates for work in the polar station were significantly lower in neuroticism, slightly lower in openness to experience and higher in conscientiousness than the general Polish population. Moreover, there was a significant discrepancy in neuroticism between winterers and those not selected for wintering. This result was not observed in the female group. Potential reasons for study outcomes will be discussed in the article.

Archaea possess characteristic membrane-spanning lipids that are thought to contribute to the adaptation to extreme environments. However, the biosynthesis of these lipids is poorly understood. Here, we identify a radical S-adenosyl-L-methionine (SAM) enzyme that synthesizes glycerol monoalkyl glycerol tetraethers (GMGTs). The enzyme, which we name GMGT synthase (Gms), catalyzes the formation of a C(sp3)–C(sp3) linkage between the two isoprenoid chains of glycerol dialkyl glycerol tetraethers (GDGTs). This conclusion is supported by heterologous expression of gene gms from a GMGT-producing species in a methanogen, as well as demonstration of in vitro activity using purified Gms enzyme. Additionally, we show that genes encoding putative Gms homologs are present in obligate anaerobic archaea and in metagenomes obtained from oxygen-deficient environments, and appear to be absent in metagenomes from oxic settings. The biosynthesis of membrane-spanning lipids in archaea is poorly understood. Here, Li et al. identify an archaeal enzyme that forms a C(sp3)–C(sp3) linkage between isoprenoid chains for the synthesis of membrane-spanning GMGT lipids, and show that the corresponding gene is exclusively found in obligate anaerobic archaea and in metagenomes from oxygen-deficient environments. [ABSTRACT FROM AUTHOR]

Developmental plasticity evolves in heterogeneous environmental conditions as long as individuals can accurately perceive them. A paradigmatic example of developmental plasticity is the ability of amphibian larvae to alter growth and development in response to the risk of pond drying. Such responses are often found in amphibian species breeding in highly dynamic water bodies with high desiccation risk. The inselbergs of the Guianan Shield are rocky outcrops with extremely high and fluctuating temperatures and a marked seasonality in precipitation. During the rainy season, eroded depressions form precipitation-dependent pools with a high and variable risk of desiccation within the timeframe of a few days. The frog Leptodactylus lithonaetes specializes in breeding in this extreme environment, and its tadpoles are thus forced to cope with desiccation risk by adjusting their developmental trajectories and physiological performance. We experimentally assessed the effect of different levels of desiccation risk, under controlled temperature conditions, on developmental rate, growth, and temperature-dependent locomotor performance in tadpoles of Leptodactylus lithonaetes. We did not find an effect of desiccation risk on developmental rate, but under simulated drying conditions, tadpoles showed larger body size, greater body mass, and enhanced locomotor performance compared to constant (high or low) water levels. These results suggest that drying pools offer cues that trigger developmental and behavioral changes in these tadpoles, enabling them to enhance growth over a short time span without accelerating development. We discuss the potential compensatory mechanisms behind these responses and highlight the need for further investigations in species with semiterrestrial life histories in extreme environments. [ABSTRACT FROM AUTHOR]

Nature exhibits an enormous diversity of organisms that thrive in extreme environments. From snow algae that reproduce at sub-zero temperatures to radiotrophic fungi that thrive in nuclear radiation at Chernobyl, extreme organisms raise many questions about the limits of life. Is there any environment where life could not "find a way"? Although many individual extremophilic organisms have been identified and studied, there remain outstanding questions about the limits of life and the extent to which extreme properties can be enhanced, combined or transferred to new organisms. In this review, we compile the current knowledge on the bioengineering of extremophile microbes. We summarize what is known about the basic mechanisms of extreme adaptations, compile synthetic biology's efforts to engineer extremophile organisms beyond what is found in nature, and highlight which adaptations can be combined. The basic science of extremophiles can be applied to engineered organisms tailored to specific biomanufacturing needs, such as growth in high temperatures or in the presence of unusual solvents. [ABSTRACT FROM AUTHOR]