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The high content and quality of protein in Andean legumes make them valuable for producing protein hydrolysates using proteases from bacteria isolated from extreme environments. This study aimed to carry out a single-step purification of a haloprotease from Micrococcus sp. PC7 isolated from Peru salterns. In addition, characterize and apply the enzyme for the production of bioactive protein hydrolysates from underutilized Andean legumes. The PC7 protease was fully purified using only tangential flow filtration (TFF) and exhibited maximum activity at pH 7.5 and 40 °C. It was characterized as a serine protease with an estimated molecular weight of 130 kDa. PC7 activity was enhanced by Cu2+ (1.7-fold) and remained active in the presence of most surfactants and acetonitrile. Furthermore, it stayed completely active up to 6% NaCl and kept ̴ 60% of its activity up to 8%. The protease maintained over 50% of its activity at 25 °C and 40 °C and over 70% at pH from 6 to 10 for up to 24 h. The determined Km and Vmax were 0.1098 mg mL−1 and 273.7 U mL−1, respectively. PC7 protease hydrolyzed 43%, 22% and 11% of the Lupinus mutabilis, Phaseolus lunatus and Erythrina edulis protein concentrates, respectively. Likewise, the hydrolysates from Lupinus mutabilis and Erythrina edulis presented the maximum antioxidant and antihypertensive activities, respectively. Our results demonstrated the feasibility of a simple purification step for the PC7 protease and its potential to be applied in industrial and biotechnological processes. Bioactive protein hydrolysates produced from Andean legumes may lead to the development of nutraceuticals and functional foods contributing to address some United Nations Sustainable Development Goals (SDGs). [ABSTRACT FROM AUTHOR]

The fabrication of light-weight, highly impact-resistant, and energy-absorbent materials is urgently demanded in many facets of the society from body armor to aerospace engineering, especially under an extreme environment. Carbon nanotubes (CNTs), one of the strongest and toughest materials ever found, also have good conductivity, chemical stability, and thermal stability, etc, making them a competitive candidate as building blocks to help achieve the above goal. In this work, a kind of CNT network was prepared by using chlorosulfonic acid (CSA) to release the internal stress of super-aligned carbon nanotube films (SA-CNTF) and dendritic polyamide amine (PAMAM) to further introduce multiple hydrogen bonds and interlocking structures. The fabricated bioinspired carbon nanotube network films (PAMAM@C-CNTF) have a high toughness of 45.97 MJ/m3, showing an increase of 420% compared to neat SA-CNTF. More importantly, the anti-impact performance of the films (e.g., with a maximum specific energy absorption of 1.40 MJ/kg under 80–100 m/s projectile impact) is superior to that of conventional protective materials from steel and Kevlar fiber, and also exceeds that of any other reported carbon-based materials. The hierarchical energy dissipation mechanism was further revealed through experiment and simulation. Additional functions including intelligent heating/anti-icing, ultraviolet protection, as well as electromagnetic interference shielding properties make these network films have great potential in practical multi-protection applications, especially under an extreme environment. [ABSTRACT FROM AUTHOR]

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]

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 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]

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]

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]

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]

Despite of excellent thermal properties and high sputtering resistance, pure tungsten cannot fully satisfy the requirements for plasma facing materials in future high-duty cycle nuclear fusion reactions due to the coupled extreme environments, including the high thermal loads, plasma exposure, and radiation damage. Here, we demonstrated that tungsten-based composite materials fabricated using spark-plasma sintering (SPS) present promising solutions to these challenges. Through the examination of two model systems, i.e., tungsten-zirconium composite for producing porous tungsten near the surface and dispersoid-strengthened tungsten, we discussed both the strengths and limitations of the SPS-fabricated materials. Our findings point towards the need for future studies aimed at optimizing the SPS process to achieve desired microstructures and effective control of oxygen impurities in the tungsten-based composite materials. [ABSTRACT FROM AUTHOR]

Microbial life is not restricted to any particular setting. Over the past several decades, it has been evident that microbial populations can exist in a wide range of environments, including those with extremes in temperature, pressure, salinity, and pH. Bacteria and Archaea are the two most reported types of microbes that can sustain in extreme environments, such as hot springs, ice caves, acid drainage, and salt marshes. Some can even grow in toxic waste, organic solvents, and heavy metals. These microbes are called extremophiles. There exist certain microorganisms that are found capable of thriving in two or more extreme physiological conditions simultaneously, and are regarded as polyextremophiles. Extremophiles possess several physiological and molecular adaptations including production of extremolytes, ice nucleating proteins, pigments, extremozymes and exopolysaccharides. These metabolites are used in many biotechnological industries for making biofuels, developing new medicines, food additives, cryoprotective agents etc. Further, the study of extremophiles holds great significance in astrobiology. The current review summarizes the diversity of microorganisms inhabiting challenging environments and the biotechnological and therapeutic applications of the active metabolites obtained as a response to stress conditions. Bioprospection of extremophiles provides a progressive direction with significant enhancement in economy. Moreover, the introduction to omics approach including whole genome sequencing, single cell genomics, proteomics, metagenomics etc., has made it possible to find many unique microbial communities that could be otherwise difficult to cultivate using traditional methods. These findings might be capable enough to state that discovery of extremophiles can bring evolution to biotechnology. [ABSTRACT FROM AUTHOR]

Due to the advantage of strength enhancement without increasing the structural weight, stiffeners are commonly used in many engineering structures. However, during their service life, these stiffened structures are usually exposed to an extreme environment, which may cause damage. Most of the researchers have carried out the work to study the unreinforced plate's stability behaviour considering interlaminar skin debonding in the hygrothermal condition. However, in the current investigation, the buckling capacity of stiffened composite plates debonded at the contact of plate and stiffener under non-uniform edge loading in hygrothermal conditions is studied. The study is performed by developing a computationally efficient finite element formulation. In the present research, the plate and the flange of T-stiffener are formulated by adopting a 9-noded heterosis element preventing the shear locking. In contrast, a 3-noded isoparametric beam element is used to formulate the stiffener web by accommodating the torsion correction factor, considerably reducing the computational cost. In the current study, the debond is modelled by creating a dummy node, and further interpenetration of the nodes is prevented by introducing a fictitious spring in the debonded region. Due to the highly uneven stress variation, a dynamic approach is employed to estimate the buckling constant by utilizing two sets of boundary conditions. Three schemes of hygrothermally stable laminates (θ/(90-θ))s, (22.5/− 67.5)s, and (77.5/− 12.5)s are considered to identify the stiffened plate configuration with enhanced buckling capacity when subjected to various non-uniform loading patterns. Further, extensive parametric investigations are conducted on the obtained stiffened plate with improved performance under a hygrothermal environment by considering debond at the skin–stiffener interface. It is found that debonded plate's stability is substantially affected by moisture. On the other hand, depending on the stiffener position and hygrothermal load intensity, the stiffener's depth-to-width ratio substantially affects the debonded plate's stability. Therefore, this investigation can be considered as a benchmark study for the stability performance of the debonded reinforced composite panel, which partially reduces the 2-D problem to 1-D element, thereby improving the computational cost. [ABSTRACT FROM AUTHOR]

This study examines hourly precipitation data from 128 national meteorological observation stations within the Sichuan Basin (SB) spanning 2002 to 2021, focusing on warm-season (May to September) hourly extreme precipitation (HEP) and its events (HEPEs). Significant spatial variability is observed across the SB regarding thresholds, amount, intensity, and frequency of warm-season HEP. HEP predominantly occurs from mid-July to early August, with a higher probability of peak events in the afternoon during these months. HEPEs starting from midnight to early morning tend to have prolonged durations, whereas, in the afternoon, prompt-duration HEPEs lasting within 3 h are more prevalent. Around the basin, the northwest and northeast regions experience HEPEs with higher precipitation amounts but fewer occurrences. The northwestern region encounters shorter-duration HEPEs with greater rainfall intensity, while the northeastern region records a higher frequency of moderate or weak HEPEs lasting ≥ 13 h. Comparatively, the southwestern basin exhibits a higher frequency of nocturnal HEP events characterized by relatively lower rainfall intensity. The eastern Sichuan parallel ridge-valley area in the southeastern basin demonstrates more frequent HEP occurrences with lower rainfall intensities. Additionally, mountainous regions of the southeastern SB and the southern branch of the eastern Sichuan parallel ridge-valley exhibit lower HEPE amounts but greater numbers of events, primarily characterized by prompt-duration events in the afternoon. These findings unveil the diverse spatiotemporal patterns of warm-season HEP and HEPEs within the SB, highlighting the regional variability across different geographical zones. This study provides insights for managing vital resources and timely natural disaster evacuation. [ABSTRACT FROM AUTHOR]

India is dependent on rainfall for agriculture, food security and economic advancements. Spatial and temporal variability of rainfall is well reported, as well as the recent upsurge of extremes due to climate change. In Maharashtra, rainfall intensity varies widely from very high (coasts) to low (west-interior). Extreme value analysis (EVA) of heavy annual rainfall for the various districts of Maharashtra was conducted to ascertain the following for each district: suitable extreme value distribution; extreme (high) annual rainfall; efficacy of gap-filling for missing annual record/s. The suitability of various statistical distributions for representing high annual rainfall values was evaluated using Anderson–Darling test (quantitative), quantile and probability plots (qualitative). The gap-filling exercise resulted in minor variations (<10%) in the estimated extremes, positive as well as negative, for different cases. Therefore, the results of EVA on the actual records are advocated. The suitable distributions for 35 districts are presented in maps and Frechet distribution was adjudged suitable for almost 60% of districts. The estimated extremes for all districts are listed for different return periods for ready reference. These values would be useful for the planning and construction of hydraulic structures, water resources and reservoir management, design and planning of irrigation. Research highlights: Suitable probability distribution functions for modelling the extremes of annual rainfall in each district of Maharashtra have been identified and the parameters have been provided. Extreme values of annual rainfall for each district in Maharashtra for selected return periods have been presented. Evaluation was performed on whether the gaps in the annual rainfall records would affect EVA of the annual rainfall in the districts of Maharashtra. [ABSTRACT FROM AUTHOR]

The plans of international space agencies to return to the Moon and explore deep space, including Mars, highlight the challenges of human adaptation and stress the need for a thorough analysis of the factors that facilitate, limit and modify human performance under extreme environments. This study investigates the influence of partial gravity on behavioural (error rate and reaction time) and neuronal parameters (event-related potentials) through parabolic flights. Brain cortical activity was assessed using EEG from 18 participants who solved a neurocognitive task, consisting of a mental arithmetic task and an auditory oddball paradigm, during Earth (1G), Lunar (0.16G + 0.25G) and Martian gravity (0.38G + 0.5G) for 15 consecutive parabolas. Data shows higher electrocortical activity in Earth gravity compared to Lunar and Martian gravity in the parietal lobe. No differences in participants' performance were found among the gravity levels. Event-related potentials displayed gravity-dependent variations, though limited stimuli recording suggests caution in interpretation. Data suggests a threshold between Earth and Martian gravity within the different gravities responsible for physiological changes, but it seems to vary greatly between individuals. The altered neuronal communication could be explained with a model developed by Kohn and Ritzmann in 2018. The increasing intracranial pressure in weightlessness changes the properties of the cell membrane of neurons and leads to a depolarisation of the resting membrane potential. The findings underscore the individuality of physiological changes in response to gravity alterations, signalling the need for further investigations in future studies. [ABSTRACT FROM AUTHOR]

This study examines the spatial and temporal changes in temperature and precipitation extremes from 1951 to 2020 in the West African transboundary Benue River Basin, which frequently experiences impacts from extreme events. The existing studies in the region have relied on sparse observation data, hindering a comprehensive understanding of the spatial variability of climate extremes. High-resolution gridded climate data can be used to explore how climate extremes vary spatially and temporally across transboundary river basins. This study is the first attempt to employ 0.25° × 0.25° daily ERA5 temperature and precipitation data to comprehensively assess spatiotemporal changes of climatic extremes in a West African transboundary river basin. The study applied the non-parametric Mann-Kendall test and Sen's slope method to analyze temperature and precipitation extremes in the Benue River Basin. Results show a significant increase in mean maximum temperature (Tmax) of approximately ≥ 2 °C, indicating rising mean Tmax. Analysis of temperature indices reveals significant positive trends, with the number of warm days (TX90p) increasing by 8%. In contrast, evaluations of maximum 1-day (RX1day) and 5-day (RX5day) precipitation exhibit widespread reductions of 22.5% and 45%, respectively, indicating decreasing rainfall over most areas. Examinations of consecutive dry days (CDD) display higher mean changes in the northern basin extending to western Chad (70 to ≥ 110 days), revealing a link between lower annual precipitation and increased temperatures. However, we also found a basin-wide decrease in CDD ranging from ≤-2 to ≥-10 days. Overall, this study shows that the maximum temperature increases faster than the minimum temperature in the study area and that extreme temperature changes are more pronounced than extreme precipitation. These findings hold crucial implications for understanding the evolving climate dynamics in this vulnerable basin, emphasizing the urgency for adaptive measures in the face of escalating climate challenges. [ABSTRACT FROM AUTHOR]

Natural environments vary, and organisms cope with this variation in two general ways: local adaptation and phenotypic plasticity, although these strategies often overlap and interact. This study explored how local adaptation, phenotypic plasticity, and their interactions shaped phenotypic variation in populations of Poecilia mexicana, an extremophile fish living in adjacent but ecologically divergent habitats. By comparing populations from the wild with fish raised in a common-garden environment, we evaluated how genetic differentiation between populations and plasticity contributed to the phenotypic variation observed in nature. We quantified variation in the size of six organs (brain, eyes, gills, heart, liver, and gastrointestinal tract), routine metabolic rate, and body shape. We found evidence for genetic differences between populations impacting the expression of the majority of traits, in addition to or in interaction with phenotypic plasticity and other predictor variables. Overall, our results suggest that trait divergence between populations was at least in part driven by evolutionary change and not just merely by plasticity induced by environmental differences between habitats. Future studies will have to rigorously test whether evolutionary divergence was caused by natural selection and what traits represent adaptations to the different ecological conditions. [ABSTRACT FROM AUTHOR]

We conducted this study to investigate the relationship between environmental stressors and mesozooplankton fluxes in inner Kongsfjorden, Svalbard. The ongoing Arctic amplification, characterized by phenomena such as increased temperatures, glacial and watershed runoff, and diminishing ice cover, poses significant challenges to marine ecosystems. Our multi-year time-series analysis (2010–2018) of mesozooplankton, collected from a moored automatic sediment trap at approximately 87 m depth, aims to elucidate seasonal and interannual variations in fluxes within this Arctic fjord. We integrate meteorological, hydrological, and chemical datasets to assess their influence on zooplankton populations. Principal component analysis reveals the impact of seawater characteristics on mesozooplankton fluxes and composition, while two-way ANOVA highlights the role of seasonality in driving variations in our dataset. We observe a decrease in swimmer fluxes following the maxima mass flux event (from 2013 onwards), coupled with an increase in community diversity, possibly attributed to copepod decline and functional diversity. Notably, sub-Arctic boreal species such as Limacina retroversa have been detected in the sediment trap since 2016. Our continuous multi-year dataset captures the physical, chemical, and biological dynamics in this extreme environment. With Arctic amplification in Kongsfjorden and increasing submarine and watershed runoff, we anticipate significant shifts in mesozooplankton communities in the medium to long-term. This underscores the urgency for further research on their adaptation to changing environmental conditions and the potential introduction of alien species. [ABSTRACT FROM AUTHOR]

Variable temperature regimes that expose corals to sublethal heat stress have been recognized as a mechanism to increase coral thermal tolerance and lessen coral bleaching. However, there is a need to better understand which thermal regimes maximize coral stress hardening. Here, standardized thermal stress assays were used to determine the relative thermal tolerance of three divergent genera of corals (Acropora, Pocillopora, Porites) originating from six reef sites representing an increasing gradient of annual mean diel temperature fluctuations of 1–3 °C day−1. Bleaching severity and dark-acclimated photochemical yield (i.e., Fv/Fm) were quantified following exposure to five temperature treatments ranging from 23.0 to 36.3 °C. The greatest thermal tolerance (i.e., Fv/Fm effective dose 50) was found at the site with intermediate mean diel temperature variability (2.2 °C day−1), suggesting there is an optimal priming exposure that leads to maximal thermal tolerance. Interestingly, Acropora and Pocillopora originating from the least thermally variable regimes (< 1.3 °C day−1) had lower thermal tolerance than corals from the most variable sites (> 2.8 °C day−1), whereas the opposite was true for Porites, suggesting divergent responses across taxa. Remarkably, comparisons across global studies revealed that the range in coral thermal tolerance uncovered in this study across a single reef (< 5 km) were as large as differences observed across vast latitudinal gradients (300–900 km). This finding indicates that local gene flow could improve thermal tolerance between habitats. However, as climate change continues, exposure to intensifying marine heatwaves is already compromising thermal priming as a mechanism to enhance coral thermal tolerance and bleaching resistance. [ABSTRACT FROM AUTHOR]

Highlights: The SiO2 nanofiber membranes and MXene@c-MWCNT6:4 as one unit layer (SMC1) were bonded together with 5 wt% PVA solution. When the structural unit is increased to three layers, the resulting SMC3 has an average electromagnetic interference SET of 55.4 dB and a low thermal conductivity of 0.062 W m−1 K−1. SMCx exhibit stable electromagnetic interference shielding and excellent thermal insulation even in extreme heat and cold environment. A lightweight flexible thermally stable composite is fabricated by combining silica nanofiber membranes (SNM) with MXene@c-MWCNT hybrid film. The flexible SNM with outstanding thermal insulation are prepared from tetraethyl orthosilicate hydrolysis and condensation by electrospinning and high-temperature calcination; the MXene@c-MWCNTx:y films are prepared by vacuum filtration technology. In particular, the SNM and MXene@c-MWCNT6:4 as one unit layer (SMC1) are bonded together with 5 wt% polyvinyl alcohol (PVA) solution, which exhibits low thermal conductivity (0.066 W m−1 K−1) and good electromagnetic interference (EMI) shielding performance (average EMI SET, 37.8 dB). With the increase in functional unit layer, the overall thermal insulation performance of the whole composite film (SMCx) remains stable, and EMI shielding performance is greatly improved, especially for SMC3 with three unit layers, the average EMI SET is as high as 55.4 dB. In addition, the organic combination of rigid SNM and tough MXene@c-MWCNT6:4 makes SMCx exhibit good mechanical tensile strength. Importantly, SMCx exhibit stable EMI shielding and excellent thermal insulation even in extreme heat and cold environment. Therefore, this work provides a novel design idea and important reference value for EMI shielding and thermal insulation components used in extreme environmental protection equipment in the future. [ABSTRACT FROM AUTHOR]

Gauge-measured precipitation (Pm) is prone to negative bias; therefore, using corrected gauge-measured precipitation (Pc) is critical in climate and hydrology studies, although it is utilized insufficiently in existing research. This study uses Pm and Pc to establish extreme precipitation indices (EPIs) and compares the differences in their evolution characteristics and their responses to large-scale circulation indices (LSCIs). Theil's slope and the modified Mann–Kendall test are used to identify the evolution characteristics of EPIs. Probabilistic condition selection and momentary conditional independence and the Liang-Kleeman information flow are adopted to evaluate the causal relationship between the EPIs and LSCIs. The main results are as follows: (1) The magnitude, intensity, and frequency of the Pc-based EPIs are higher than those of the Pm-based EPIs in China, except for the consecutive dry days (CDD). This result suggests that previous estimates of Pm-based EPIs underestimated the magnitude, intensity, and frequency at most stations, especially in the Southwestern River where droughts and flood areas may have been underestimated. Thus, the frequency of Southwestern River droughts and floods and their sudden transitions may be higher. (2) The slope increases in the Pc-based EPIs (except for the Southwestern River), and their significance levels are lower than those of the Pm-based EPIs. Conversely, the slope decreases in the Pc-based EPIs (except for the Southwestern River), and their significance levels (except for the Songliao River) are higher than those of the Pm-based EPIs. The internal variability of the climate system and the external forcing in some basins are the reasons for the significantly increasing slopes of very wet days (R95p), simple daily intensity index (SDII), and extremely wet days (R99p). However, the significant decreasing slopes are attributed to internal climate variability. (3) Unlike the Pm-based EPIs, the Pc-based EPIs did not alter the causal relationship with LSCIs, indicating that Pc did not change the causal relationship with LSCIs. The trend, magnitude, intensity, and frequency differ for Pc and Pm. Therefore, Pc and Pm data should be used cautiously in meteorological, hydrological, ecological, environmental, and agricultural simulations in future research. [ABSTRACT FROM AUTHOR]

Spray drying is regarded as one of the most economical methods utilized in the production of liposome powder in industry. However, the poor reconstruction of the powder following rehydration imposes constraints on its potential utilization. In this study, three membrane stabilizers, Poloxamer 188 (P188), trehalose (Tre), and Tween 80 (T80) were selected due to their distinct localization behaviors, and their impact on the reconstruction of rehydrated liposomes was discussed. The mannitol-based spray-dried liposome powder with excellent reconstruction was successfully developed. After rehydrating the powder, the particle size (Dh) and polydispersion index (PDI) of mannitol-encapsulated liposome powder (Bla) significantly increase. Although adding leucine improved the dispersion of the powder (Bla/Leu), the increase in Dh and PDI after rehydration was more significant, changed from 172.79 nm and 0.075 for Bla to 459.97 nm and 0.291 for Bla/Leu, the micropolarity and hydrophobicity of membrane also increased, indicating a poorer reconstruction. The addition of extra membrane stabilizers enhanced the stability of the liposomes after rehydration. Specifically, the addition of T80 reduced the changes in Dh and PDI caused by leucine to 118.39 nm and 0.015, while the changes of ANS fluorescence intensity and I1/I3 to 178.66 a.u and 0.02. Raman spectroscopy revealed that the addition of membrane stabilizer greatly reduced the disorder of the acyl chain, especially the T80. It could be the embedding mode of T80 on liposomes and its excellent solubilization played the best role. It also showed the best stability in extreme environments such as acidity and ionic strength. [ABSTRACT FROM AUTHOR]

Anthropogenic CO 2 emissions are expected to significantly impact climate patterns, including extreme heat events. The influence of plants on land-atmosphere water and energy exchanges plays a crucial role in shaping these heat extremes. The response of vegetation growth and physiology to elevated CO 2 , both directly and indirectly, will determine their contribution to future heat extremes. In this study, we employed a suite of CMIP6 earth system models (ESMs) to differentiate between the effects of radiative forcing and vegetation forcing under elevated CO 2 background on extreme heat and precipitation events in China. The CO 2 vegetation forcing may reduce transpiration and weak vegetation cooling impact, leading to a decrease in clouds and precipitation under 2 × CO 2 and 4 × CO 2 scenarios. Our findings indicate that CO 2 -driven vegetation forcing (VEG) decreases extreme precipitation and increases dry days numbers in most humid regions of China, despite the increase in transpiration resulting from the saving of soil moisture and aboveground biomass enhancement due to CO 2 fertilization. Additionally, VEG intensifies the frequency and intensity of future heatwaves over most of China. Both radiative forcing and vegetation forcing have a stronger impact on humid area than dry area. The findings indicate that solely considering the radiative impacts of CO 2 is insufficient to explain the projected variations in extreme precipitation and heat changes. It suggests that CO 2 physiological forcing might play a role in influencing the differences in projected water and energy characteristics among different climate models. [ABSTRACT FROM AUTHOR]

The aim of this investigation is to identify a representative set of climate model projections for the Awash Basin using accessible general circulation model (GCM) predictors from the Coupled Model Intercomparison Project Phase 5 (CMIP5) archive. Various approaches were employed to systematically shortlist and select suitable climate models under two representative concentration pathways (RCPs). For RCP4.5, 105 GCMs were used and for RCP8.5, 78 GCMs were used to select the best performance models for a climate change impact study in this basin. These approaches are combined in the current study to create a three-step sequential procedure for choosing climate models: (1) initial selection of climate models based on the range of projected changes in climatic means, (2) refined selection based on the range of projected changes in climatic extremes, and (3) final selection based on the ability of the climate models to simulate historical climate changes between 1971–2000 and 2071–2100 were analyzed. Five corners of possible extreme future scenarios (wet-warm, wet-cold, dry-warm, dry-cold, and the 50th percentile of the temperatures) were used. A total of 25 GCMs were selected for RCP4.5 and RCP8.5 based on the range of expected mean temperature and rainfall change. Based on the range of extreme changes, 10 GCMs were chosen. Five GCMs were ultimately selected for each RCP4.5 and RCP8.5 by merging all three stages. The findings of this study will contribute valuable insights to better understand and adapt to the impacts of climate change in the Awash River Basin and similar regions. [ABSTRACT FROM AUTHOR]

Cyanobacteria inhabiting extreme environments constitute a promising source for natural products with biotechnological applications. However, they have not been studied in-depth for this purpose due to the difficulties in their isolation and mass culturing. The Atacama Desert suffers one of the highest solar irradiances that limits the presence of life on its hyperarid core to endolithic microbial communities supported by cyanobacteria as primary producers. Some of these cyanobacteria are known to produce scytonemin, a UV-screening liposoluble pigment with varied biotechnological applications in cosmetics and other industries. In this work we carried out a strain selection based on growth performance among 8 endolithic cyanobacteria of the genera Chroococcidiopsis, Gloeocapsa and Gloeocapsopsis isolated from non-saline rocks of the Atacama Desert. Then we investigated the influence of NaCl exposure on scytonemin production yield. Results in the selected strain (Chroococcidiopsis sp. UAM571) showed that rising concentrations of NaCl lead to a growth decrease while triggering a remarkable increase in the scytonemin content, reaching maximum values at 20 g L−1 of NaCl over 50-fold higher scytonemin contents than those obtained without NaCl. Altogether, these findings point out to cyanobacteria from the Atacama Desert as potentially suitable candidates for pilot-scale cultivation with biotechnological purposes, particularly to obtain scytonemin. [ABSTRACT FROM AUTHOR]

The Arabian Peninsula accounts for approximately 6% of the world's coral reefs. Some thrive in extreme environments of temperature and salinity. Using 51 Autonomous Reef Monitoring Structure (ARMS), a standardized non-destructive monitoring device, we investigated the spatial patterns of coral reef cryptobenthic diversity in four ecoregions around the Arabian Peninsula and analyzed how geographical and/or environmental drivers shape those patterns. The mitochondrial cytochrome c oxidase subunit I (COI) gene was used to identify Amplicon Sequence Variants and assign taxonomy of the cryptobenthic organisms collected from the sessile and mobile fractions of each ARMS. Cryptobenthic communities sampled from the two ecoregions in the Red Sea showed to be more diverse than those inhabiting the Arabian (Persian) Gulf and the Gulf of Oman. Geographic distance revealed a stronger relationship with beta diversity in the Mantel partial correlation than environmental distance. However, the two mobile fractions (106–500 µm and 500–2000 µm) also had a significant correlation between environmental distance and beta diversity. In our study, dispersal limitations explained the beta diversity patterns in the selected reefs, supporting the neutral theory of ecology. Still, increasing differences in environmental variables (environmental filtering) also had an effect on the distribution patterns of assemblages inhabiting reefs within short geographic distances. The influence of geographical distance in the cryptofauna assemblages makes these relevant, yet usually ignored, communities in reef functioning vulnerable to large scale coastal development and should be considered in ecosystem management of such projects. [ABSTRACT FROM AUTHOR]

Characterisation of genomic variation among corals can help uncover variants underlying trait differences and contribute towards genotype prioritisation in coastal restoration projects. For example, there is growing interest in identifying resilient genotypes for transplantation, and to better understand the genetic processes that allow some individuals to survive in specific conditions better than others. The coral species Pocillopora acuta is known to survive in a wide range of habitats, from reefs artificial coastal defences, suggesting its potential use as a starter species for ecological engineering efforts involving coral transplantation onto intertidal seawalls. However, the intertidal section of coastal armour is a challenging environment for corals, with conditions during periods of emersion being particularly stressful. Here, we scanned the entire genome of P. acuta corals to identify the regions harbouring single nucleotide polymorphisms (SNPs) and copy number variations (CNVs) that separate intertidal colonies (n = 18) from those found in subtidal areas (n = 21). Findings revealed 74,391 high quality SNPs distributed across 386 regions of the P. acuta genome. While the majority of the detected SNPs were in non-coding regions, 12% were identified in exons (i.e. coding regions). Functional SNPs that were significantly associated with intertidal colonies were found in overrepresented genomic regions linked to cellular homeostasis, metabolism, and signalling processes, which may represent local environmental adaptation in the intertidal. Interestingly, regions that exhibited CNVs were also associated with metabolic and signalling processes, suggesting P. acuta corals living in the intertidal have a high capacity to perform biological functions critical for survival in extreme environments. [ABSTRACT FROM AUTHOR]

Maintaining sufficient cerebral oxygen metabolism is crucial for human survival, especially in challenging conditions such as high-altitudes. Human cognitive neural activity is sensitive to fluctuations in oxygen levels. However, there is a lack of publicly available datasets on human behavioural responses and cerebral dynamics assessments during the execution of conflicting tasks in natural hypoxic environments. We recruited 80 healthy new immigrant volunteers (males, aged 20 ± 2 years) and employed the Stroop cognitive conflict paradigm. After a two-week exposure to both high and low-altitudes, the behavioural performance, prefrontal oxygen levels, and electroencephalography (EEG) signals were recorded. Comparative analyses were conducted on the behavioural reaction times and accuracy during Stroop tasks, and statistical analyses of participants' prefrontal oxygen levels and EEG signals were performed. We anticipate that our open-access dataset will contribute to the development of monitoring devices and algorithms, designed specifically for measuring cerebral oxygen and EEG dynamics in populations exposed to extreme environments, particularly among individuals suffering from oxygen deficiency. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the independent and combined effects of hypoxia (FiO2 = 13.5%) and cold (− 20 °C) on physiological and perceptual responses to endurance exercise. Methods: 14 trained male subjects ( V. O2max: 64 ± 5 mL/kg/min) randomly performed a discontinuous maximal incremental test to exhaustion on a motorized treadmill under four environmental conditions: Normothermic-Normoxia (N), Normothermic-Hypoxia (H), Cold-Normoxia (C) and Cold-Hypoxia (CH). Performance and physiological and perceptual responses throughout exercise were evaluated. Results: Maximal WorkLoad (WL) and WL at lactate threshold (LT) were reduced in C (− 2.3% and − 3.5%) and H (− 18.0% and − 21.7%) compared to N, with no interactive (p = 0.25 and 0.81) but additive effect in CH (− 21.5% and − 24.6%). Similarly, HRmax and Vemax were reduced in C (− 3.2% and − 14.6%) and H (− 5.0% and − 7%), showing additive effects in CH (− 7.7% and − 16.6%). At LT, additive effect of C (− 2.8%) and H (− 3.8%) on HR reduction in CH (− 5.7%) was maintained, whereas an interactive effect (p = 0.007) of the two stressors combined was noted on Ve (C: − 3.1%, H: + 5.5%, CH: − 10.9%). [La] curve shifted on the left in CH, displaying an interaction effect between the 2 stressors on this parameter. Finally, RPE at LT was exclusively reduced by hypoxia (p < 0.001), whereas TSmax is synergistically reduced by cold and hypoxia (interaction p = 0.047). Conclusion: If compared to single stress exposure, exercise performance and physiological and perceptual variables undergo additive or synergistic effects when cold and hypoxia are combined. These results provide new insight into human physiological responses to extreme environments. [ABSTRACT FROM AUTHOR]

In drylands, where resources are scarce, wild edible plant (WEP) knowledge is crucial to overcome food scarcity. Understanding the distribution pattern of local ecological knowledge (LEK) about WEP and identifying knowledge holders are key steps to assessing the resilience and vulnerability of knowledge systems. However, little is known about how WEP knowledge is distributed across life stages and gender of people living in arid regions. Here, we study the distribution of WEP knowledge within a small-scale society from southwestern Madagascar, a region known for its dry climate and related food crises. We worked with Tanalana male and female children and adults using semi-structured interviews and free listings. Tanalana people display a sophisticated LEK adapted to the extreme environment in which they live, with a distinct distribution pattern regarding theoretical and practical knowledge across life stages and gender. While women and men cited similar WEP, children and adults cited different sets of WEP, suggesting they hold differentiated bodies of theoretical knowledge, however our results suggest similarity in practical knowledge across life-stage and gender. We argue that resource limitation and food scarcity might be so pervasive in the area that extensive sharing of knowledge on WEP could be an adaptation to the extremely dry environment. [ABSTRACT FROM AUTHOR]

Background: X-ray imaging addresses many challenges with visible light imaging in extreme environments, where optical diagnostics such as digital image correlation (DIC) and particle image velocimetry (PIV) suffer biases from index of refraction changes and/or cannot penetrate visibly occluded objects. However, conservation of intensity—the fundamental principle of optical image correlation algorithms—may be violated if ancillary components in the X-ray path besides the surface or fluid of interest move during the test. Objective: The test series treated in this work sought to characterize the safe use of fiber-epoxy composites in aerospace and aviation industries during fire accident scenarios. Stereo X-ray DIC was employed to measure test unit deformation in an extreme thermal environment involving a visibly occluded test unit, incident surface heating to temperatures above 600oC, and flames and soot from combusting epoxy decomposition gasses. The objective of the current work is to evaluate two solutions to resolve the violation of conservation of intensity that resulted from both the test unit and the thermal chamber deforming during the test. Methods: The first solution recovered conservation of intensity by pre-processing the path-integrated X-ray images to isolate the DIC pattern of the test unit from the thermal chamber components. These images were then correlated with standard, optical DIC software. The second solution, called Path-Integrated Digital Image Correlation (PI-DIC), modified the fundamental matching criterion of DIC to account for multiple, independently-moving components contributing to the final image intensity. The PI-DIC algorithm was extended from a 2D framework to a stereo framework and implemented in a custom DIC software. Results: Both solutions accurately measured the cylindrical shape of the undeformed test unit, recovering radii values of R = 76.20 ± 0.12 mm compared to the theoretical radius of R theor = 76.20 mm. During the test, the test unit bulged asymmetrically as decomposition gasses pressurized the interior and eventually burned in a localized jet. Both solutions measured the heterogeneous radius of this bulge, which reached a maximum of approximately R = 91 mm, with a discrepancy of 2–3% between the two solutions. Conclusions: Two solutions that resolve the violation of conservation of intensity for path-integrated X-ray images were developed. Both were successfully employed in a stereo X-ray DIC configuration to measure deformation of an aluminum-skinned, fiber-epoxy composite test unit in a fire accident scenario. [ABSTRACT FROM AUTHOR]

Endocrine disruption compounds can be found in various daily products, like pesticides, along with cosmetic and pharmaceutical commodities. Moreover, occurrence of EDCs in the wastewater alarms the urgency for their removal before discharge owing to the harmful effect for the environment and human health. Compared to implementation of physical and chemical strategies, cultivation of photosynthetic microorganisms has been acknowledged for their high efficiency and eco-friendly process in EDCs removal along with accumulation of valuable byproducts. During the process, photosynthetic microorganisms remove EDCs via photodegradation, bio-adsorption, -accumulation, and -degradation. Regarding their high tolerance in extreme environment, photosynthetic microorganisms have high feasibility for implementation in wastewater treatment plant. However, several considerations are critical for their scaling up process. This review discussed the potency of EDCs removal by photosynthetic microorganisms and focused on the efficiency, mechanism, challenge, along with the prospect. Details on the mechanism's pathway, accumulation of valuable byproducts, and recent progress in scaling up and application in real wastewater were also projected in this review. [ABSTRACT FROM AUTHOR]

Assessment of climate reanalysis data for land (ECMWF Re-Analysis v5; ERA5-Land) covering the last seven decades reveals regions where extreme daily mean temperatures are rising faster than the average rate of temperature rise of the 6 months of highest background warmth. However, such extreme temperature acceleration is very heterogeneous, occurring only in some places including regions of Europe, the western part of North America, parts of southeast Asia and much of South America. An ensemble average of Earth System Models (ESMs) over the same period also shows acceleration across land areas, but this enhancement is much more spatially uniform in the models than it is for ERA5-Land. Examination of projections from now to the end of the 21st Century, with ESMs driven by the highest emissions Shared Socio-economic Pathway scenario (SSP585) of future changes to atmospheric greenhouse gases, also reveals larger warming during extreme days for most land areas. The increase in high-temperature extremes is driven by different processes depending on location. In northern mid-latitudes, a key driver is often a decrease in the evaporative fraction of the available energy, consistent with soil drying. By contrast, the acceleration of high-temperature extremes in tropical Africa is primarily due to increased available energy. These two drivers combine via the surface energy balance to equal the sensible heat flux, which we find is often strongly correlated with the areas where the acceleration of high-temperature extremes is largest. [ABSTRACT FROM AUTHOR]

The Canary Islands are one of the main destinations for mass tourism in the European context, characterized by the absence of seasonality in tourist activity. Moreover, the level of activity increases during the winters, coinciding with a greater probability of extreme rainfall events, whose danger seems to be increasing as a result of climate change. Owing to its pronounced orography, the southern coast of the island of Gran Canaria houses several tourist settlements built along ravines and steeply sloping terrain. This scenario presents considerable risk because of spatial probability of landslide occurrence. The case of San Agustín, especially, serves to test the model of tourist urbanization along the hillside, demonstrating its high fragility in the face of extreme rainfall events. Especially owing to its importance in providing assistance in emergency situations, its vulnerability has been analyzed with regard to accessibility, which is entirely dependent on road mobility. The growth model of San Agustín serves as an example of mass tourism in small islands, allowing urban planners and designers to assess corrective measures based on managing its existing road infrastructure and open spaces right from the planning stage. [ABSTRACT FROM AUTHOR]

Hadal trenches are extreme environments situated over 6000 m below sea surface, where enormous hydrostatic pressure affects the biochemical cycling of elements. Recent studies have indicated that hadal trenches may represent a previously overlooked source of fixed nitrogen loss; however, the mechanisms and role of hydrostatic pressure in this process are still being debated. To this end, we investigate the effects of hydrostatic pressure (0.1 to 115 MPa) on the chemical profile, microbial community structure and functions of surface sediments from the Mariana Trench using a Deep Ocean Experimental Simulator supplied with nitrate and oxygen. We observe enhanced denitrification activity at high hydrostatic pressure under oxic conditions, while the anaerobic ammonium oxidation – a previously recognized dominant nitrogen loss pathway – is not detected. Additionally, we further confirm the simultaneous occurrence of nitrate reduction and aerobic respiration using a metatranscriptomic dataset from in situ RNA-fixed sediments in the Mariana Trench. Taken together, our findings demonstrate that hydrostatic pressure can influence microbial contributions to nitrogen cycling and that the hadal trenches are a potential nitrogen loss hotspot. Knowledge of the influence of hydrostatic pressure on anaerobic processes in oxygenated surface sediments can greatly broaden our understanding of element cycling in hadal trenches. Hadal trenches are the deepest oceanic ecosystems, with water depth over 6000 m, and are among the least explored habitats on Earth. This research demonstrates that high hydrostatic pressure enhances denitrification activity under oxic conditions, potentially making hadal trenches fixed nitrogen loss hotpots. [ABSTRACT FROM AUTHOR]

Marine sponges host diverse microbial communities. Although we know many of its ecological patterns, a deeper understanding of the polar sponge holobiont is still needed. We combine high-throughput sequencing of ribosomal genes, including the largest taxonomic repertoire of Antarctic sponge species analyzed to date, functional metagenomics, and metagenome-assembled genomes (MAGs). Our findings show that sponges harbor more exclusive bacterial and archaeal communities than seawater, while microbial eukaryotes are mostly shared. Furthermore, bacteria in Antarctic sponge holobionts establish more cooperative interactions than in sponge holobionts from other environments. The bacterial classes that established more positive relations were Bacteroidia, Gamma- and Alphaproteobacteria. Antarctic sponge microbiomes contain microbial guilds that encompass ammonia-oxidizing archaea, ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, and sulfur-oxidizing bacteria. The retrieved MAGs showed a high level of novelty and streamlining signals and belong to the most abundant members of the main microbial guilds in the Antarctic sponge holobiont. Moreover, the genomes of these symbiotic bacteria contain highly abundant functions related to their adaptation to the cold environment, vitamin production, and symbiotic lifestyle, helping the holobiont survive in this extreme environment. [ABSTRACT FROM AUTHOR]

The changes of soil moisture, salinity, and nutrients by halophyte colonization in high-salinity environment profoundly affect the assembly and structure of microbial communities. However, salt marshes in arid region have received little attention. This study was conducted in Lianhuachi Lake, a typical inland salt marsh wetland in China, to determine the physicochemical characteristics of salt crusts in [Kalidium cuspidatum (Ung.-Sternb.) Grub.] colonization areas and bulk soil, respectively, and to analyze the microbial community structure of salt crusts by high-throughput sequencing. Kalidium cuspidatum colonization significantly decreased total salinity, soil water content, and water-soluble ions of salt crusts and increased total carbon, total nitrogen, and total phosphorus content. At the same time, changes in physicochemical properties caused by Kalidium cuspidatum colonization affect the ecological processes of bacterial, fungal, and archaeal community assemblies in salt crusts. In addition, cross-kingdom network analysis showed that Kalidium cuspidatum colonization increased the complexity and stability of microbial networks in salt crust soils. Functional projections further showed that bacterial diversity had a potential driving effect on the nitrogen cycle function of salt crust. Our study further demonstrated the different ecological strategies of microorganisms for halophyte colonization in extreme environments and contributed to the understanding of restoration and management of salt marsh wetlands in arid region. [ABSTRACT FROM AUTHOR]

Extremotolerant and extremophilic fungi are an important part of microbial communities that thrive in extreme environments. Among them, the black yeasts are particularly adaptable. They use their melanized cell walls and versatile morphology, as well as a complex set of molecular adaptations, to survive in conditions that are lethal to most other species. In contrast to extremophilic bacteria and archaea, these fungi are typically extremotolerant rather than extremophilic and exhibit an unusually wide ecological amplitude. Some extremely halotolerant black yeasts can grow in near-saturated NaCl solutions, but can also grow on normal mycological media. They adapt to the low water activity caused by high salt concentrations by sensing their environment, balancing osmotic pressure by accumulating compatible solutes, removing toxic salt ions from the cell using membrane transporters, altering membrane composition and remodelling the highly melanized cell wall. As protection against extreme conditions, halotolerant black yeasts also develop different morphologies, from yeast-like to meristematic. Genomic studies of black yeasts have revealed a variety of reproductive strategies, from clonality to intense recombination and the formation of stable hybrids. Although a comprehensive understanding of the ecological role and molecular adaptations of halotolerant black yeasts remains elusive and the application of many experimental methods is challenging due to their slow growth and recalcitrant cell walls, much progress has been made in deciphering their halotolerance. Advances in molecular tools and genomics are once again accelerating the research of black yeasts, promising further insights into their survival strategies and the molecular basis of their adaptations. Key points: • Black yeasts show remarkable adaptability to environmental stress • Black yeasts are part of microbial communities in hypersaline environments • Halotolerant black yeasts utilise various molecular and morphological adaptations [ABSTRACT FROM AUTHOR]

Anthropogenic activities generate increasing disturbance in wildlife especially in extreme environments where species have to cope with rapid environmental changes. In Antarctica, while studies on human disturbance have mostly focused on stress response through physiological and behavioral changes, local variability in population dynamics has been addressed more scarcely. In addition, the mechanisms by which breeding communities are affected around research stations remain unclear. Our study aims at pointing out the fine-scale impact of human infrastructures on the spatial variability in Adélie penguin (Pygoscelis adeliae) colonies dynamics. Taking 24 years of population monitoring, we modeled colony breeding success and growth rate in response to both anthropic and land-based environmental variables. Building density around colonies was the second most important variable explaining spatial variability in breeding success after distance from skua nests, the main predators of penguins on land. Building density was positively associated with penguins breeding success. We discuss how buildings may protect penguins from avian predation and environmental conditions. The drivers of colony growth rate included topographical variables and the distance to human infrastructures. A strong correlation between 1-year lagged growth rate and colony breeding success was coherent with the use of public information by penguins to select their initial breeding site. Overall, our study brings new insights about the relative contribution and ecological implications of human presence on the local population dynamics of a sentinel species in Antarctica. [ABSTRACT FROM AUTHOR]

Extreme weather events and frequent meteorological disasters pose significant threats to vegetation growth in the context of climate change. However, information regarding the impact of extreme climate events on vegetation in the ecologically fragile Karst area has been lacking. This study aims to fill this knowledge gap by quantifying changes in extreme temperature and the normalized difference vegetation index (NDVI) while exploring the relationship between extreme temperature and NDVI in Guangxi's Karst area, China. Our analysis reveals a pronounced trend toward extreme warming in the study region from 2000 to 2019. Warm days TX90d, TX95d, and TX99d (count of days where daily maximum temperature TX > 90th, 95th, and 99th percentile) significantly (P < 0.05) increased 7.1, 5.5, and 2.0 days per decade. Warm nights TN90d, TN95d, and TN98d (count of nights where daily minimum temperature TN > 90th, 95th, and 98th percentile) significantly (P < 0.05) increased 9.7, 6.8, and 4.2 days per decade, with the increase rate greater than warm days. Annual days for daily maximum temperature higher than 35 °C also increased 3.4 days per decade. The annual NDVI increased 0.04 per decade. We have identified a negative linear relationship between the trends of very cold and very warm days (i.e., very cold days TX01d and hot days TX99d) and NDVI. In contrast, the annual NDVI demonstrates a positive correlation with the annual days for daily maximum temperature higher than 35 °C. The results suggested that climate warming might to some extent benefit the vegetation growth. Nevertheless, it is imperative to enhance vegetation protection efforts, particularly in regions experiencing extreme warm and cold. [ABSTRACT FROM AUTHOR]

The classes Dothideomycetes and Eurotiomycetes include constitutively melanized fungi adapted to extreme conditions and they are widely distributed in diverse hostile habitats worldwide. Yet, despite the growing interest in these fungi, there is a considerable gap of knowledge on their functionality. Their genomic analysis is still in its infancy and the possibility to understand their adaptive strategies and exploit their potentialities in bioremediation is very limited. Here, we supply a genome catalog of 118 black fungi, encompassing different ecologies, phylogenies and lifestyles, as a first example of a comparative genomic study at high level of diversity. Results indicate that, as a rule, Dothideomycetes show more variable genome size and that larger genomes are associated with harshest conditions; low temperature tolerance and DNA repair capacity are overrepresented in their genomes. In Eurotiomycetes high temperature tolerance and capacity to metabolize hydrocarbons are more frequently present and these abilities are positively correlated with the human presence. The genomic features are consistent with the prevalent ecologies in the two classes. Indeed, Dothideomycetes are more common in cold and dry environments with high capacity for DNA repair being consistent with the normally highly UV-impacted conditions in their habitats; in contrast, Eurotiomycetes spread mainly in hot human-impacted sites with industrial pollution. Mean annual temperature and isothermality are positively correlated with tolerance to high temperatures in Dothideomycetes, suggesting that, despite their preference for the cold, they are potentially equipped to survive even when temperatures rise due to the global warming. [ABSTRACT FROM AUTHOR]

Microbial communities in the active layer play a crucial role in the biogeochemical cycles of Antarctic pristine ecosystems. Here, 16S rRNA gene sequencing was used to investigate bacterial communities in active layer of five different geological sites related to the compositional variation of the geological bedrock, including Neogene volcanic or Cretaceous rocks and or marine sediments areas of distinct elevation. Local variations in the thickness of the active layer (50–80 cm) were observed on the Ulu Peninsula, James Ross Island, and the southwest coast of Vega Island, Antarctica during sampling in 2019. High bacterial diversity was detected in all sampling sites. Significant site effects on bacterial composition with increased Chloroflexota and decreased Flavobacteriaceae were only observed between the highest elevation Johnson Mesa 2 plateau and coastal areas. The overall effect of the depth was reflected by the increased of e.g., Cyanobacteria, Propionibacterium, Staphylococcus in the upper surface and Chloroflexota, Acidobacteriota, Actinomycetota at depths below 30 cm. The huge number of unassigned bacteria indicated a potential source of new bacterial species and their ecological role in this extreme environment. For the first time, we showed that the effect of depth on bacterial composition was more significant than the effect of geological bedrock from these previously unexplored regions. [ABSTRACT FROM AUTHOR]

A global study of extreme value (1 in 100-year return period) tropical cyclone generated waves is conducted across all tropical cyclone basins. The study uses a 1000 year tropical cyclone synthetic track database to force a validated parametric wave model. The resulting distributions of extreme significant wave height show that values in the North Atlantic and Western Pacific basins are the largest globally. This is partly due to the relative intensities and frequencies of occurrence of storms in these basins but also because the typical velocities of forward movement of storms are larger and hence can sustain the generation of larger waves. These larger values of velocity of forward movement tend to occur at higher latitudes. As a result, in both of these basins the largest extreme waves occur at higher latitudes than the maximum tropical cyclone winds. In all other tropical cyclone basins, storms tend to propagate more east–west and hence the maximum values of extreme significant wave height and wind speed occur at comparable latitudes. [ABSTRACT FROM AUTHOR]

With global warming, extreme weather frequently and severely appears globally. Extreme precipitation is one of the extreme weather events that can cause many natural disasters, such as floods and waterlogging. In this study, Global Precipitation Climatology Project (GPCP) daily precipitation data were used to investigate extreme precipitation and its contribution to annual precipitation in different global climate regions and typical river basins. The climate types included equatorial climates (EC), arid climates (AC), warm temperate climates (WTC), snowy climates (SC) and polar climates (PC). R99p, Rx5day, CWD and R20 was selected as extreme precipitation indices in this study; extreme precipitation days were defined by CWD and R20. The results showed that EC and WTC had higher extreme precipitation level; SC and PC had lower extreme precipitation amounts and days than AC. R99p, Rx5day and CWD monitored higher extreme precipitation contribution degrees in AC; however, R20 monitored higher contribution degrees in EC and WTC. R99p, Rx5day and CWD showed higher extreme precipitation contribution degrees in North Africa, the Middle East, Australia and northwestern China; R20 showed higher contribution degrees in South America, the southeastern United States and South Asia. Based on historical observational data, Heilongjiang Basin (HB), Yellow River Basin (YERB), Yangtze River Basin (YARB), Ganges River Basin (GRB), Danube River Basin (DRB) and Mekong River Basin (MERB) had high-frequency extreme precipitation in summer. The research results are helpful for understanding the characteristics of extreme precipitation and provide a reference for flood control and disaster reduction in different climatic regions and main river basins. [ABSTRACT FROM AUTHOR]

Radiation and corrosion can be coupled to each other in non-trivial ways and such coupling is of critical importance for the performance of materials in extreme environments. However, it has been rarely studied in ceramics and therefore it is not well understood to what extent these two phenomena are coupled and by what mechanisms. Here, we discover that radiation-induced chemical changes at grain boundaries of ceramics can have a significant (and positive) impact on the corrosion resistance of these materials. Specifically, we demonstrate using a combination of experimental and simulation studies that segregation of C to grain boundaries of silicon carbide leads to improved corrosion resistance. Our results imply that tunning of stoichiometry at grain boundaries either through the sample preparation process or via radiation-induced segregation can provide an effective method for suppressing surface corrosion. [ABSTRACT FROM AUTHOR]

Cladonia borealis is a lichen that inhabits Antarctica's harsh environment. We sequenced the whole genome of a C. borealis culture isolated from a specimen collected in Antarctica using long-read sequencing technology to identify specific genetic elements related to its potential environmental adaptation. The final genome assembly produced 48 scaffolds, the longest being 2.2 Mbp, a 1.6 Mbp N50 contig length, and a 36 Mbp total length. A total of 10,749 protein-coding genes were annotated, containing 33 biosynthetic gene clusters and 102 carbohydrate-active enzymes. A comparative genomics analysis was conducted on six Cladonia species, and the genome of C. borealis exhibited 45 expanded and 50 contracted gene families. We identified that C. borealis has more Copia transposable elements and expanded transporters (ABC transporters and magnesium transporters) compared to other Cladonia species. Our results suggest that these differences contribute to C. borealis' remarkable adaptability in the Antarctic environment. This study also provides a useful resource for the genomic analysis of lichens and genetic insights into the survival of species isolated from Antarctica. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "The role and risks of selective adaptation in extreme coral habitats" published in Nature Communications. The correction addresses errors in the calculation of the density of reef corals, which affected the density values shown in Figure 3e and the statistical results reported in the legend for Figure 3 and in the Results section. The corrected version of Figure 3 and the corrected statistical values have been updated in both the HTML and PDF versions of the article. Supplementary information and updated source data are also provided. [Extracted from the article]

Extreme rainfall prior to a flood event is often a necessary condition for its occurrence; however, rainfall alone is not always an indicator of flood severity. Antecedent wetness condition of a catchment is another important factor which strongly influences the flood magnitudes. The key role of soil moisture in driving floods is widely recognized; however, antecedent conditions of deeper saturated zone may contribute to river floods. Here, we assess how closely the flood magnitudes are associated to extreme rainfall, soil moisture and baseflow in 70 catchments of Peninsular India for the period 1979–2018. Annual flood magnitudes have declined across most of the catchments. Effect of flow regulations is also assessed to understand the impact of human interventions on flood characteristics. Reservoir regulation has positive effect by reducing the flood peak and volume, whereas the duration of flood events has increased after the construction of dams. Baseflow exhibits similar patterns of trends as floods, whereas trends in rainfall and soil moisture extremes are weakly correlated with trends in flood magnitudes. Baseflow is found to be more strongly influencing the flood magnitudes than soil moisture at various time lags. Further analysis with event coincidence analysis confirms that baseflow has stronger triggering effect on river floods in Peninsular India. [ABSTRACT FROM AUTHOR]

The potential consequences for mankind could be disastrous due to global warming, which arises from an increase in the average temperature on Earth. The elevation in temperature primarily stems from the escalation in the concentration of greenhouse gases (GHG) such as CO2, CH4, and N2O within the atmosphere. Among these gases, methane (CH4) is particularly significant in driving alterations to the worldwide climate. Methanotrophic bacteria possess the distinctive ability to employ methane as both as source of carbon and energy. These bacteria show great potential as exceptional biocatalysts in advancing C1 bioconversion technology. The present review describes recent findings in methanotrophs including aerobic and anaerobic methanotroph bacteria, phenotypic characteristics, biotechnological potential, their physiology, ecology, and native multi-carbon utilizing pathways, and their molecular biology. The existing understanding of methanogenesis and methanotrophy in soil, as well as anaerobic methane oxidation and methanotrophy in temperate and extreme environments, is also covered in this discussion. New types of methanogens and communities of methanotrophic bacteria have been identified from various ecosystems and thoroughly examined for a range of biotechnological uses. Grasping the processes of methanogenesis and methanotrophy holds significant importance in the development of innovative agricultural techniques and industrial procedures that contribute to a more favorable equilibrium of GHG. This current review centers on the diversity of emerging methanogen and methanotroph species and their effects on the environment. By amalgamating advanced genetic analysis with ecological insights, this study pioneers a holistic approach to unraveling the biopotential of methanotrophs, offering unprecedented avenues for biotechnological applications. Key points: • The physiology of methanotrophic bacteria is fundamentally determined. • Native multi-carbon utilizing pathways in methanotrophic bacteria are summarized. • The genes responsible for encoding methane monooxygenase are discussed. [ABSTRACT FROM AUTHOR]