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The hypometabolism induced by fasting has great potential in maintaining health and improving survival in extreme environments, among which thyroid hormone (TH) plays an important role in the adaptation and the formation of new energy metabolism homeostasis during long-term fasting. In the present review, we emphasize the potential of long-term fasting to improve physical health and emergency rescue in extreme environments, introduce the concept and pattern of fasting and its impact on the body’s energy metabolism consumption. Prolonged fasting has more application potential in emergency rescue in special environments. The changes of THs caused by fasting, including serum biochemical characteristics, responsiveness of the peripheral and central hypothalamus-pituitary-thyroid (HPT) axis, and differential changes of TH metabolism, are emphasized in particular. It was proposed that the variability between brain and liver tissues in THs uptake, deiodination activation and inactivation is the key regulatory mechanism for the cause of peripheral THs decline and central homeostasis. While hypothalamic tanycytes play a pivotal role in the fine regulation of the HPT negative feedback regulation during long-term fasting. The study progress of tanycytes on thyrotropin-releasing hormone (TRH) release and deiodination is described in detail. In conclusion, the combination of the decrease of TH metabolism in peripheral tissues and stability in the central HPT axis maintains the basal physiological requirement and new energy metabolism homeostasis to adapt to long-term food scarcity. The molecular mechanisms of this localized and differential regulation will be a key research direction for developing measures for hypometabolic applications in extreme environment. [ABSTRACT FROM AUTHOR]

Flexible pressure sensors with high sensitivity over a broad sensing range are of great value in daily life and highly desired in various extreme environment, from human motion inspection to heavy industrial robots to high energy radiation and extremely cold/high temperature environments. However, it remains a significant challenge for a single pressure sensor to simultaneously possess high sensitivity and broad detection range due to the trade‐off between these two properties. Here, a high‐performance pressure sensor is developed based on flexible modified silicon rubber/functionalized carbon nanotube (MSR/FCNT). The designed nested‐cell architecture and molecular surface modification strategy endow the pressure sensor with high sensitivity (>28 kPa−1) over 10 MPa sensing range, an ultralow detection limit (≈0.94 Pa), an ultrahigh pressure resolution (0.0075%) at a pressure of 3 MPa, and a low fatigue over 10 000 repetitive cycles even at an extremely high pressure of 5 MPa. Furthermore, the resulting sensor presents excellent durability after freezing at extreme cold temperature (−80 °C) as well as resistance to high temperature (200 °C) and high‐energy X‐ray radiation. The proposed nested‐cell architecture is a generic strategy for porous materials to achieve broad range high sensitivity. [ABSTRACT FROM AUTHOR]

Introduction: The accurate estimation of postmortem interval (PMI), the time between death and discovery of the body, is crucial in forensic science investigations as it impacts legal outcomes. PMI estimation in extremely cold environments becomes susceptible to errors and misinterpretations, especially with prolonged PMIs. This study addresses the lack of data on decomposition in extreme cold by providing the first overview of decomposition in such settings. Moreover, it proposes the first postmortem microbiome prediction model for PMI estimation in cold environments, applicable even when the visual decomposition is halted. Methods: The experiment was conducted on animal models in the secondcoldest region in the United States, Grand Forks, North Dakota, and covered 23 weeks, including the winter months with temperatures as low as -39°C. Random Forest analysis models were developed to estimate the PMI based either uniquely on 16s rRNA gene microbial data derived from nasal swabs or based on both microbial data and measurable environmental parameters such as snow depth and outdoor temperatures, on a total of 393 samples. Results: Among the six developed models, the best performing one was the complex model based on both internal and external swabs. It achieved a Mean Absolute Error (MAE) of 1.36 weeks and an R2 value of 0.91. On the other hand, the worst performing model was the minimal one that relied solely on external swabs. It had an MAE of 2.89 weeks and an R2 of 0.73. Furthermore, among the six developed models, the commonly identified predictors across at least five out of six models included the following genera: Psychrobacter (ASV1925 and ASV1929), Carnobacterium (ASV2872) and Pseudomonas (ASV1863). Discussion: The outcome of this research provides the first microbial model able to predict PMI with an accuracy of 9.52 days over a six-month period of extreme winter conditions. [ABSTRACT FROM AUTHOR]

The increased availability of quality genomic data has greatly improved the scope and resolution of our understanding of the recent evolutionary history of wild species adapted to extreme environments and their susceptibility to anthropogenic impacts. The guanaco (Lama guanicoe), the largest wild ungulate in South America, is a good example. The guanaco is well adapted to a wide range of habitats, including the Sechura Desert, the high Andes Mountains to the north, and the extreme temperatures and conditions of Navarino Island to the south. Guanacos also have a long history of overexploitation by humans. To assess the evolutionary impact of these challenging habitats on the genomic diversity, we analyzed 38 genomes (∼10 to 16×) throughout their extensive latitudinal distribution from the Sechura and Atacama Desert to southward into Tierra del Fuego Island. These included analyses of patterns of unique differentiation in the north and geographic region further south with admixture among L. g. cacsilensis and L. g. guanicoe. Our findings provide new insights on the divergence of the subspecies ∼800,000 yr BP and document two divergent demographic trajectories and to the initial expansion of guanaco into the more southern portions of the Atacama Desert. Patagonian guanacos have experienced contemporary reductions in effective population sizes, likely the consequence of anthropogenic impacts. The lowest levels of genetic diversity corresponded to their northern and western limits of distribution and some varying degrees of genetic differentiation. Adaptive genomic diversity was strongly linked with environmental variables and was linked with colonization toward the south followed by adaptation. [ABSTRACT FROM AUTHOR]

Introduction: Group living skills (GLS), that is, being tidy and considerate of others, are an important skillset for teams who live and work together. However, this construct does not have a validated measure to enable an understanding of how group living skills influence team dynamics over time. We developed and validated a short measure of group living skills for teams living in extreme work environments. Methods: We collected data from 83 individuals in 24 teams living and working in space and spaceflight analog environments on missions of 45-240 days. Results: We provide evidence of reliability and validity for the GLS Survey over time and identify a two-factor structure. We also demonstrate its use as a measure of team-level dynamics and its utility as a sociometric measure to identify a person's degree of group living skills. Discussion: We outline recommendations for using this new measure in future research and applied settings to understand this unique aspect of teams living and working together. [ABSTRACT FROM AUTHOR]

Highly stretchable and cycle‐stable (high operando dynamic stretchable) zinc‐ion microbatteries that are nonharmful, environmentally friendly, and low cost are developed herein for the first time. Stretchable zinc‐ion microbatteries (SZIMBs) are fabricated by simultaneously incorporating the facile synthesis of conducting polymer‐intercalated vanadium oxide nanofibers as flexible and elastic cathode materials; the construction, design, and assembly of wavy‐type microdevices; and pre‐zincation techniques that break stereotypes. The poly(3,4‐ethylene dioxythiophene) (PEDOT)‐intercalated zinc vanadium oxide nanofiber zinc‐ion microbatteries (E‐ZVONF‐SZIMBs) manufactured by combining these strategies exhibit a maximum specific capacity of 0.16 mAh cm−2, high energy density of 0.112 mWh cm−2, and high power density of 3.5 mW cm−2 and maintain 83.7% of the initial specific capacity after 500 cycles. The E‐ZVONF‐SZIMBs maintain 78.9% of their initial specific capacity even after 7000 mechanical stretching/bending tests, exhibiting excellent operando dynamic stretchability. The stretchable zinc‐ion microbatteries show practical feasibility by maintaining 80% and 90% of the capacity at −20 and 60°C under 200% strain, respectively. These remarkable achievements in the field of stretchable zinc‐ion microbatteries are expected to have significant implications for the development of future device platforms. [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]

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]

To grow in various harsh environments, extremophiles have developed extraordinary strategies such as biofilm formation, which is an extremely complex and progressive process. However, the genetic elements and exact mechanisms underlying extreme biofilm formation remain enigmatic. Here, we characterized the biofilm-forming ability of Deinococcus radiodurans in vitro under extreme environmental conditions and found that extremely high concentrations of NaCl or sorbitol could induce biofilm formation. Meantime, the survival ability of biofilm cells was superior to that of planktonic cells in different extreme conditions, such as hydrogen peroxide stress, sorbitol stress, and high UV radiation. Transcriptome profiles of D. radiodurans in four different biofilm development stages further revealed that only 13 matched genes, which are involved in environmental information processing, carbohydrate metabolism, or stress responses, share sequence homology with genes related to the biofilm formation of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. Overall, 64% of the differentially expressed genes are functionally unknown, indicating the specificity of the regulatory network of D. radiodurans. The mutation of the drRRA gene encoding a response regulator strongly impaired biofilm formation ability, implying that DrRRA is an essential component of the biofilm formation of D. radiodurans. Furthermore, transcripts from both the wild type and the drRRA mutant were compared, showing that the expression of drBON1 (Deinococcus radioduransBON domain-containing protein 1) significantly decreased in the drRRA mutant during biofilm development. Further analysis revealed that the drBON1 mutant lacked the ability to form biofilm and DrRRA, and as a facilitator of biofilm formation, could directly stimulate the transcription of the biofilm-related gene drBON1. Overall, our work highlights a molecular mechanism mediated by the response regulator DrRRA for controlling extreme biofilm formation and thus provides guidance for future studies to investigate novel mechanisms that are used by D. radiodurans to adapt to extreme environments. [ABSTRACT FROM AUTHOR]

Ultra-high temperature ceramics (UHTCs) based on the solid solution Ta x Hf 1-x C have shown great promise as materials for extreme environments (>2500 °C) due to their improved thermo-mechanical properties. However, their dynamic response under high-impact loading remains unknown. In this study, we investigate the dynamic impact behavior and fracturing evolution of Ta x Hf 1-x C samples (with x = 0, 0.2, 0.5, 0.8, and 1) at a strain rate > 103 s-1 using the Split Hopkinson Pressure Bar (SHPB) test. Among the different compositions, Ta 0.5 Hf 0.5 C exhibits the highest compressive strength of 1870 MPa, representing a 36% improvement over TaC and 54% over HfC. High frame rate videos and deformation analysis reveal that Ta 0.5 Hf 0.5 C, characterized by extensive Ta–Hf bonding, significantly reduces the crack propagation rate by approximately 1435% compared to TaC and 4050% compared to HfC. This effect is attributed to the dislocation pile-ups, nano-twin formation, inter grain twisting exhibited mostly along {111} plane as Hf substitutes Ta in Ta x Hf 1-x C samples. Further, the surface energy is least for {111} plane eliciting the higher probability for bypassing crack propagation along this plane in Ta x Hf 1-x C. The exceptional damage tolerance and improved mechanical properties of Ta 0.5 Hf 0.5 C, compared to other solid-solution Ta x Hf 1-x C compositions, make it an extraordinary structural material for hypersonic applications. These findings provide valuable insights into the dynamic behavior of UHTCs and highlight the potential of Ta 0.5 Hf 0.5 C as a superior material for extreme environments requiring high-impact resistance. [ABSTRACT FROM AUTHOR]

The space environment is extreme for plants growth and survival as gravity (gravitropism modification, water distribution), radiations (mutations enhancers), light spectrum regime and temperature are not optimal. Photosynthetic microorganisms are a foreseen solution for supporting plant development, growth, and stress tolerance in closed environments, like those designed for space colonisation. Indeed, photosynthetic microorganisms are known as secondary metabolites producers (exopolysaccharides, indole alkaloids, fertilisers) able to impact plant stimulation. Studying their abilities, application methodologies and best strains for space agriculture may lead to developing a sustainable and efficient approach for food production. Furthermore, as these microorganisms could also be used to produce oxygen and recycle waste materials increasing their interest in closed loop systems is undeniable. In this review we provide an overview of the current state of knowledge about existing biostimulants, their effects and applications, and the potential brought by photosynthetic microorganisms for life in closed environments. Highlights Cyanobacteria's and microalgae's secondary metabolites can act as biostimulants for vascular plants when applied to the roots or the leaves. Production of secondary metabolites in cyanobacteria can be enhanced in stressful environments. Cyanobacteria can survive space-like stress by sur-producing secondary metabolites giving an advantage for space farming as a source of biostimulant compounds. [ABSTRACT FROM AUTHOR]

We report on the fabrication and characterization of a Ga 2 O 3 -based UV-C photodetector using the aerosol deposition (AD) method. By optimizing the size and crystallinity of the Ga 2 O 3 powder, we were able to obtain a uniform thin film with high transmittance (70–80%) without the need for additional heat treatment or high vacuum environments. The resulting Ga 2 O 3 film exhibited a high and selective response to 254 nm wavelength light, even without any treatment, and remained stable when exposed to γ-radiation. The photodetector also performed well in extreme temperatures (−196 °C–150 °C), making it suitable for use in harsh environments, such as the space industry. Our findings demonstrate the potential of the AD method for the fabrication of high-quality Ga 2 O 3 thin films for photodetector applications. [ABSTRACT FROM AUTHOR]

Lead-cooled fast reactors (LFRs) are considered one of the most promising technologies to meet the requirements introduced for advanced nuclear systems. LFRs have higher neutron doses, higher temperatures, higher burnup and an extremely corrosive environment. The failure studies of claddings play a vital role in improving the safety criteria of nuclear reactors and promoting research on advanced nuclear materials. This paper presented a comprehensive review of the extreme environment in LFRs based on the fuel performance analyses and transient analyses of reference LFRs. It provided a clear image of cladding failure, focusing on the underlying mechanisms, such as creep, rupture, fatigue, swelling, corrosion, etc., which are resulted from the motions of defects, the development of microcracks and accumulation of fission products to some extent. Some fundamental parameters and behavior models of Ferritic/Martensitic (F/M) steels and Austenitic stainless (AuS) steels were summarized in this paper. A guideline for cladding failure modelling was also provided to bridge the gap between fundamental material research and realistic demands for the application of LFRs. [ABSTRACT FROM AUTHOR]

The space race is entering a new era of exploration, in which the number of robotic and human missions to various places in our solar system is rapidly increasing. Despite the recent advances in propulsion and life support technologies, there is a growing need to perform analytical measurements and laboratory experiments across diverse domains of science, while keeping low payload requirements. In this context, lab-on-a-chip nanobiosensors appear to be an emerging technology capable of revolutionizing space exploration, given their low footprint, high accuracy, and low payload requirements. To date, only some approaches for monitoring astronaut health in spacecraft environments have been reported. Although non-invasive molecular diagnostics, like lab-on-a-chip technology, are expected to improve the quality of long-term space missions, their application to monitor microbiological and environmental variables is rarely reported, even for analogous extreme environments on Earth. The possibility of evaluating the occurrence of unknown or unexpected species, identifying redox gradients relevant to microbial metabolism, or testing for specific possible biosignatures, will play a key role in the future of space microbiology. In this review, we will examine the current and potential roles of lab-on-a-chip technology in space exploration and in extreme environment investigation, reporting what has been tested so far, and clarifying the direction toward which the newly developed technologies of portable lab-on-a-chip sensors are heading for exploration in extreme environments and in space. [ABSTRACT FROM AUTHOR]

The great majority of microorganisms are as-yet-uncultivated, mostly found in extreme environments. High-throughput sequencing provides data-rich genomes from single-cell and metagenomic techniques, which has enabled researchers to obtain a glimpse of the unexpected genetic diversity of "microbial dark matter." However, cultivating microorganisms from extreme environments remains essential for dissecting and utilizing the functions of extremophiles. Here, we provide a straightforward protocol for efficiently isolating prokaryotic microorganisms from different extreme habitats (thermal, xeric, saline, alkaline, acidic, and cryogenic environments), which was established through previous successful work and our long-term experience in extremophile resource mining. We propose common processes for extremophile isolation at first and then summarize multiple cultivation strategies for recovering prokaryotic microorganisms from extreme environments and meanwhile provide specific isolation tips that are always overlooked but important. Furthermore, we propose the use of multi-omics-guided microbial cultivation approaches for culturing these as-yet-uncultivated microorganisms and two examples are provided to introduce how these approaches work. In summary, the protocol allows researchers to significantly improve the isolation efficiency of pure cultures and novel taxa, which therefore paves the way for the protection and utilization of microbial resources from extreme environments. [ABSTRACT FROM AUTHOR]

The paper explores the potential of the biomorphic approach to context-based design with a focus on special-purpose mobility in the Arctic. The study seeks to contribute to the analytical and conceptual basis for developing the transport component of the Arctic life-support system, i.e., a set of objects and technologies, and knowledge and skills for handling them, allowing a person to survive and comfortably exist in severe environmental conditions. The central argument is that the system should incorporate structural components that possess not only technical but also artistic and emotional characteristics that align with the geographic (environmental and climatic), socio-cultural, and psychological peculiarities of use. This can be achieved by drawing inspiration from local nature. We probe the visual image of "soft military presence" using two case studies in different parts of the Russian Arctic: the Yamal and Chukchi peninsulas. [ABSTRACT FROM AUTHOR]

This article reports a novel lightweight integrated multifunctional composite (LIMC) with good thermal ablative and insulating properties for high temperature extreme environment. LIMC, which is an integrated woven carbon fiber preform reinforced phenolic aerogel composites, was prepared using vacuum impregnation and ambient pressure drying. The as‐prepared LIMC consisted of a dense surface layer exposed to environment, and a lightweight insulation zone to manage the heat load. The influences of weaving parameter and resin structure of LIMC on thermal protection and insulting performance were investigated. The results demonstrated that LIMC exhibited excellent ablation and insulation properties, and the weaving parameter and resin structure can affect integrated thermal protection and insulating performance. The 3D orthogonal recession layer with dense aerogels can improve the ablation resistance, while the 2.5D layer‐layer angle‐interlock with light aerogels can increase the insulation behavior of LIMC. The novel LIMC presents wide application prospects in the field of thermal protection and heat insulation. [ABSTRACT FROM AUTHOR]

Biocatalysts such as enzymes are environmentally friendly and have substrate specificity, which are preferred in the production of various industrial products. However, the strict reaction conditions in industry including high temperature, organic solvents, strong acids and bases and other harsh environments often destabilize enzymes, and thus substantially compromise their catalytic functions, and greatly restrict their applications in food, pharmaceutical, textile, bio-refining and feed industries. Therefore, developing industrial enzymes with high thermostability becomes very important in industry as thermozymes have more advantages under high temperature. Discovering new thermostable enzymes using genome sequencing, metagenomics and sample isolation from extreme environments, or performing molecular modification of the existing enzymes with poor thermostability using emerging protein engineering technology have become an effective means of obtaining thermozymes. Based on the thermozymes as biocatalytic chips in industry, this review systematically analyzes the ways to discover thermostable enzymes from extreme environment, clarifies various interaction forces that will affect thermal stability of enzymes, and proposes different strategies to improve enzymes' thermostability. Furthermore, latest development in the thermal stability modification of industrial enzymes through rational design strategies is comprehensively introduced from structure-activity relationship point of view. Challenges and future research perspectives are put forward as well. [ABSTRACT FROM AUTHOR]

Commercial mountaineering has gained widespread popularity in recent decades. Global mountaineering challenges - e.g., the Seven Summits challenge to climb the highest summit of each continent - amplify this process, and also raise the profile of individual destinations. The highest volcano on the Earth, the Ojos del Salado in the Dry Andes (Chile/Argentina) is featured in two of the major challenges (Seven Second Summits, Volcanic Seven Summits). Thus, it is a prime extreme outdoor tourism destination. The relative ease of access and the non-technical nature of the ascent have also contributed to the increasing volume of tourism. However, our observations about commercial mountaineering practices reveal surprisingly low success rates on the summit. Based on data from our decade-long environmental monitoring programme and our field experiences, we attribute this to the extreme environment and landscape of the mountain (e.g., cold and dry climate, strong winds, topographical situation, loose surface material), scarce mountaineering facilities, and potential misjudgements by inexperienced climbers. [ABSTRACT FROM AUTHOR]

Operating Offshore Floating Vertical Axis Wind Turbines (OF-VAWT) have the potential to perform well in the deep-sea area. Some researchers gave performance prediction by developing simplified computing models. However, these models have imperfections in considering load and motion nonlinearity, especially in extreme environments. In this work, a numerical model is developed composed of Computational Fluid Dynamics (CFD) and Dynamic Fluid Body Interaction (DFBI) to acquire the aero-hydrodynamic load and performance of OF-VAWT in general and extreme environments. Unsteady Reynolds-Averaged Navier-Stokes (URANS), SST k-ω and Eulerian Multi-Phase (EMP) models are combined to generate a gas-liquid two-phase flow field; the Volume of Fluid (VOF) model is employed to capture free-surface and make numerical wind-wave. DFBI superposition motion technology is proposed for local motion definition and motion solution, and overset with sliding meshes is introduced to achieve the grid motion. The numerical approach is verified by the tunnel and tank experimental data from the available literature. Simulation results of general cases, such as variable wind speed, wave height and wave length, are compared to discuss the effect of environmental parameters on load and performance. Comparison shows that this straight-bladed OF-VAWT is more susceptible to wind speed. Furthermore, the aerodynamic load generated by the shut-down rotor is still significant in extreme environment, which has implications for the development of OF-VAWT controller. [ABSTRACT FROM AUTHOR]

The Antarctic is an extreme environment for plants. Several invasive plant species, however, have invaded the sub-Antarctic Southern Ocean islands and increasingly threaten the vulnerability of maritime and continental Antarctica, particularly with changes in climate. We provide an overview of issues to consider with regard to the impact, ecology and management of non-native plants in the Antarctic, focusing on knowledge gained and recent research results from the sub-Antarctic with possible application to Antarctica. We provide a brief review of literature and bring together experience and previously unpublished research with Poa annua and Stellaria media on Macquarie Island. While no one set of biological characteristics predicts plant invasiveness in the sub-Antarctic, all are adapted to survive extreme cold conditions and persistence is enabled through large and long-lived soil seed banks. Ecological drivers for invasion include accidental human introductions and continuing movement, along with animal and other disturbance to soil. The invasive cold-tolerant plant species now prevalent on sub-Antarctic islands also pose a threat to Antarctica due to a warming climate and so efforts should continue to prevent further spread, while developing effective, low-impact control and eradication options to protect these high-value extreme ecosystems. [ABSTRACT FROM AUTHOR]

Ti6Al4V and Al6061 are aerospace alloys used in lunar structural components and rovers owing to their high specific strength. However, they deteriorate rapidly when subjected to demanding conditions of the lunar environment, such as extreme thermal cycles, solar particle radiation, and abrasive regolith. Cryo-milled powders were employed to deposit hBN-reinforced protective titanium coatings through plasma spray (atmospheric-APS and vacuum-VPS) with 2 and 10 vol% of hBN on Ti6Al4V and Al6061 substrates. These coatings were evaluated for durability under extreme lunar-like conditions, including thermal cycling, electron radiation, and synergistic (electron radiation-thermal cycle) exposure. The coatings exhibited radiation-induced hardening, resulting in a substantial increase in their microhardness ~20–40 % compared to virgin condition. Bright-field transmission electron microscopy (TEM) analysis reveals the presence of high dislocation densities, black dot defects, and dislocation clusters, providing evidence of the severe impact of synergistic environmental stresses. Ball-on-disk tribological tests were conducted in the presence of JSC-1 A lunar regolith simulant to evaluate the wear performance of coatings. Compared to conventional Ti6Al4V substrate, 50 %, 90 %, and 70 % reductions in wear volume were observed in the Ti/2 vol% hBN coatings in thermal-only, radiation-only, and synergistic environments. Neutron shielding tests indicate that the synergistic coatings offer higher neutron shielding performance by up to 28 % compared to virgin coatings, attributed to improved neutron capture by 10B isotopes. Upon a comprehensive assessment and ranking of multiple coatings under varying conditions, the VPS Ti/2 vol% hBN coating emerges as the top choice for protection against extreme radiation and thermal cycles for future lunar explorations. • Novel Ti-hBN coatings for lunar structures tested for durability under extreme conditions. • Wear and neutron shielding response of coatings for lunar environments was probed. • Evidence of dislocation clusters was obtained after radiation exposure. • Ranking identifies VPS Ti/2 vol% hBN as the best coating for lunar conditions. [ABSTRACT FROM AUTHOR]

Rock varnish, a dark-coloured natural feature rich in manganese (Mn), iron (Fe), and clay minerals that forms on rock surfaces and subsurface rock fractures in extremely dry and cold environments, is believed to provide nutritional support to microbiota. Because varnish supports an extensive microbial community, this rock coating is considered a substrate for potential microbial life to thrive in extreme environments on Earth. Although research in the past decades have advanced understanding of the varnish microbiome, little is known about this microbial community in settings that are high altitude (lower oxygen), dry, and cold. We present here new morphological, chemical, and rock magnetic results of rock varnish from this environmental setting, the Ladakh, a potential analogue site for life in extreme environments. Our results include the presence of putative magnetofossils-in the form of nanochains present in the rock varnish layer. Further, the higher concentrations of oxidised Mn4+ and carboxylic acid functionality on the varnish surface revealed organic signatures. These collective results point towards the enriched concentration of magnetic minerals on the varnish layer that are possibly sourced through biotic forms. Consequently, the rock varnish can serve as an archive of ancient environmental records, as well as a potential geomaterial for astrobiological studies from the Martian analogue field location of Ladakh, which needs to be explored further for extensive biogeochemical studies. • Ladakh's rock varnish as a potential geomaterial for Mars analogue studies in extreme settings. • Presence of putative magnetofossil-like entities in the varnish layer reported for the first time. • Higher levels of oxidized Mn4+ and carboxylic acids on the varnish surface revealed organic signatures through XPS analysis. • Comprehensive magnetic characterisation of rock varnish unveils magnetite as the dominant magnetic mineral. [ABSTRACT FROM AUTHOR]

The novel concept of the review is a focus on the organisms living in the sea ice and what mechanisms they have developed for their existence. The review describes the physical environment of the sea ice and the microorganisms living there as microalgae, bacteria, virus, fungi, meio- and macrofauna where they inhabit the brine channels and exposed to low temperatures as down to −25 °C and high salinities—up to 300. Nutrients, O2, CO2, pH, light, and UV are also identified as stressors regarding the metabolism of the microorganisms. It is argued that sea ice must be recognized as an extreme environment as based on records of very high or very low concentrations or intensities of the stressors that living organisms in the ice are exposed to and able to endure. Each taxonomic group of organisms in the sea ice are dealt with in detail in terms of the explicit stressors the group is exposed to, and specifically what known mechanisms that the organisms have amended to secure existence and life. These mechanisms are known for some group of organisms as autotrophs, bacteria, meio- and macrofauna but less so for virus and fungi. The review concludes that sea ice is an extreme environment where the stressors vary significantly in both space and time, both in consort and solitary, classifying organisms living there as polyextremophiles and extremophiles. The review relates further to extraterrestrial moons covered with sea ice and these habitats and points toward sea ice on Earth for prospective studies until further technological advances. [ABSTRACT FROM AUTHOR]

The shallow hydrothermal vents (HVs) of Kueishan Island are considered as a template for studying the extremes of sulfide-polluted and acidified water. The present study examined the biological and spatiotemporal aspects of mesozooplankton mortality in waters around this extreme HV environment. Zooplankton sample collection was carried out in three monsoonal periods and the results revealed that there was a significant decrease in the mortality of total mesozooplankton with increasing distance from the HVs. The overall mortality of mesozooplankton showed a significant negative correlation with sea surface temperature and pH. Particularly, mortality of copepods showed a significant negative correlation with pH, whereas it was significantly positive correlated with sea surface temperature in the southwest monsoon prevailing period. Overall, the results may imply a situation that zooplankton will encounter in the more acidified environment of a future ocean. • Hydrothermal vents exert different mortalities on different mesozooplankton taxa. • Low pH significantly increases mesozooplankton mortality. • Lethal mesozooplankton effects decrease with increasing distance from hydrothermal vents. • Mesozooplankton mortalities differ with monsoonal periods. [ABSTRACT FROM AUTHOR]

In the exploration of the moon and outer space, our preliminary mission lies in the construction of lunar base. To make lunar concrete with local materials on the moon becomes the key technology to promote the construction of lunar bases. In order to further study the feasibility of using lunar in-situ resources to prepare concrete and build a lunar base, the environment and resources on the lunar surface are analyzed, and the severe challenges brought by extreme environment to concrete preparation and the prerequisites of in-situ resources are clarified. In this paper, the research progress of lunar concrete is summarized from the aspects of raw material acquisition, concrete preparation methods and performance, and the comparative analysis of cement concrete, sulfur concrete, geopolymer concrete and polymer concrete is carried out. Existing studies have shown that in the acquisition of raw materials, sulfur concrete has more advantages, cement concrete and geopolymer concrete are also feasible, but polymer, as a scarce resource on the moon, is difficult to obtain. In terms of preparation methods, cement concrete and geopolymer concrete are more suitable for the production of prefabricated components in artificial environment due to the limitation of external environment and the demand of water circulation, while the in-situ preparation methods represented by sulfur concrete and polymer concrete can be used for the connection and node reinforcement of prefabricated components on the moon. In terms of performance, the mechanical properties of the four kinds of concrete all meet the basic requirements, but the service performance in the harsh environment of the moon needs to be further studied. Meanwhile, the key location characteristics for lunar base construction in different regions are analyzed in terms of topography, environment and in-situ resources. Finally, the future exploration direction of the construction of the lunar bases is proposed. • Comparative study on lunar concretes: cement, sulfur, geopolymer, and polymer. • Sulfur concrete's raw material acquisition advantage; polymer's scarcity on moon. • Prefabrication versus in-situ production methods for lunar habitat construction. [ABSTRACT FROM AUTHOR]

Viruses are key players in the environment, and recent metagenomic studies have revealed their diversity and genetic complexity. Despite progress in understanding the ecology of viruses in extreme environments, viruses' dynamics and functional roles in dryland ecosystems, which cover about 45% of the Earth's land surfaces, remain largely unexplored. This study characterizes virus sequences in the metagenomes of endolithic (within rock) microbial communities ubiquitously found in hyper-arid deserts. Taxonomic classification and network construction revealed the presence of novel and diverse viruses in communities inhabiting calcite, gypsum, and ignimbrite rocks. Viral genome maps show a high level of protein diversity within and across endolithic communities and the presence of virus-encoded auxiliary metabolic genes. Phage-host relationships were predicted by matching tRNA, CRISPR spacer, and protein sequences in the viral and microbial metagenomes. Primary producers and heterotrophic bacteria were found to be putative hosts to some viruses. Intriguingly, viral diversity was not correlated with microbial diversity across rock substrates. [ABSTRACT FROM AUTHOR]

Given the unprecedented environment of long duration space exploration (LDSE), success simply cannot occur without the coordinated efforts of multiple teams, both in flight and on the ground. These multiteam systems (MTSs) are needed to achieve the complex and dynamic tasks of spaceflight missions that will be longer and more uncertain than any previously experienced. Accordingly, research is limited in terms of how to best coordinate these teams and their dynamics--and in particular, how to best prepare LDSE teams to work across time and space effectively. To begin to address these critical questions systematically, qualitative data was extracted from a series of ten interviews with experts in spaceflight and long duration analog environments. Using thematic analysis techniques, we identified several consistent themes for affective, behavioral, and cognitive elements of teamwork occurring within and between teams. We examine each of these in detail, to identify the dynamics of what is currently known and where research needs to go to provide guidance for spaceflight organizations as well as others attempting to successfully implement MTSs in novel, complex environments. [ABSTRACT FROM AUTHOR]

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The stoichiometric characteristics of plant nitrogen (N) and phosphorus (P) and their correlations with soil properties are regarded as key for exploring plant physiological and ecological processes and predicting ecosystem functions. However, quantitative studies on the relative contributions of water–salt gradients and nutrient gradients to plant stoichiometry are limited. In addition, previous studies have been conducted at the plant species and individual levels, meaning that how community-scale stoichiometry responds to soil properties is still unclear. Therefore, we selected typical sample strips from 13 sampling sites in arid regions to assess the leaf N and P levels of 23 species of desert plants and measure the corresponding soil water content, total salt content, total nitrogen content, and total phosphorus content. The aim was to elucidate the main soil properties that influence the stoichiometric characteristics of desert plants and compare the individual and community responses to those soil properties. Our results indicated that the growth of desert plants is mainly limited by nitrogen, with individual plant leaf nitrogen and phosphorus concentrations ranging from 4.08 to 31.39 mg g−1 and 0.48 to 3.78 mg g−1, respectively. Community stoichiometry was significantly lower than that of individual plants. A significant correlation was observed between the mean N concentration, P concentration, and N:P ratio of plant leaves. At the individual plant scale, aridity significantly reduced leaf N and P concentrations, while high salt content significantly increased leaf N concentrations. At the community scale, aridity had no significant effects on leaf nitrogen or phosphorus stoichiometry, while high salinity significantly increased the leaf N:P ratio and there were no significant interactions between the aridity and salinity conditions. No significant effects of soil nutrient gradients were observed on plant N and P stoichiometric characteristics at the individual or community levels. These results suggest that individual desert plants have lower leaf N and P concentrations to adapt to extreme drought and only adapt to salt stress through higher leaf N concentrations. The N and P stoichiometric characteristics of desert plant communities are not sensitive to variations in aridity and salinity in this extreme habitat. The results of this study could enhance our perceptions of plant adaptation mechanisms to extreme habitats within terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

The wide distribution and diverse varieties of chickens make them important models for studying genetic adaptation. The aim of this study was to identify genes that alter heat adaptation in commercial chicken breeds by comparing genetic differences between tropical and cold-resistant chickens. We analyzed whole-genome resequencing data of 186 chickens across various regions in Asia, including the following breeds: Bian chickens (B), Dagu chickens (DG), Beijing-You chickens (BY), and Gallus gallus jabouillei from China; Gallus gallus murghi from India; Vietnam native chickens (VN); Thailand native chickens (TN) and Gallus gallus spadiceus from Thailand; and Indonesia native chickens (IN), Gallus gallus gallus , and Gallus gallus bankiva from Indonesia. In total, 5,454,765 SNPs were identified for further analyses. Population genetic structure analysis revealed that each local chicken breed had undergone independent evolution. Additionally, when K = 5, B, BY, and DG chickens shared a common ancestor and exhibited high levels of inbreeding, suggesting that northern cold-resistant chickens are likely the result of artificial selection. In contrast, the runs of homozygosity (ROH) and the ROH-based genomic inbreeding coefficient (FROH) results for IN, TN, and VN chickens showed low levels of inbreeding. Low population differentiation index values indicated low differentiation levels, suggesting low genetic diversity in tropical chickens, implying increased vulnerability to environmental changes, decreased adaptability, and disease resistance. Whole-genome selection sweep analysis revealed 69 candidate genes, including LGR4, G6PC , and NBR1 , between tropical and cold-resistant chickens. The genes were further subjected to GO and KEGG enrichment analyses, revealing that most of the genes were primarily enriched in biological synthesis processes, metabolic processes, central nervous system development, ion transmembrane transport, and the Wnt signaling pathway. Our study identified heat adaptation genes and their functions in chickens that primarily affect chickens in high-temperature environments through metabolic pathways. These heat-resistance genes provide a theoretical basis for improving the heat-adaptation capacity of commercial chicken breeds. [ABSTRACT FROM AUTHOR]

In recent years, there has been significant interest in the application of two-dimensional materials in extreme environments like high/low-temperature conditions, strong acid/alkaline mediums, intense radiation, and high voltage/current systems. Among the various two-dimensional materials, hexagonal boron nitride (h-BN) has gained great attention due to its exceptional properties such as chemical inertness, high-temperature resistance, insulation capabilities, and strong adsorption of cosmic radiation. However, despite these attractive properties, h-BN has not been widely adopted in scale production due to the high cost and complexity associated with its current synthesis methods. Furthermore, the modification of h-BN is necessary to further study its potential. To comprehensively understand and utilize h-BN in extreme environments, this review provides a summary of its basic structure and properties, focusing on the different compositions and structures of h-BN. Then, modification methods like controlling thickness, creating defects, and introducing functional groups are included in part of the synthesis and properties influencing factors. Through this, the application of h-BN in extreme environments is put forward. Moreover, the development of current h-BN utilization in extreme environments is illustrated and future application and research direction are also emphasized. [Display omitted] • The advantages of boron nitride for extreme environments are illustrated. • Factors that influence h-BN's properties in extreme environments are discussed. • h-BN's application in different extreme environments is summarized. • Perspective of future h-BN's application in extreme environments is proposed. [ABSTRACT FROM AUTHOR]

Members of coccoid green algae have been documented in various extreme environments. In this article, a unicellular green alga was found to slowly grow in high concentration (3.6 g/L) and pure calcium chloride solution in the laboratory. It was successfully cultured and a taxonomic study combined approaches of morphological and molecular methods was conducted to determine its classification attribution, which was followed by a preliminary physiology research to explore its unique tolerance characteristics against calcium chloride stress. The strain was identified as Parachlorella kessleri by very similar morphology and the same phylogenetic position. The morphological differences among the three species in genus Parachlorella were then discussed and the characteristic traits of absent or thin mucilaginous envelop and mantel‐shaped chloroplast for P. kessleri were supported. In addition, the almost strictly spherical shape of adult cells could further distinguish the P. kessleri from the other two species. The tolerant characteristics to CaCl2 stress for this strain were confirmed and the limit concentration was revealed as between 2000 and 4000 times than the standard BG11 culture concentration. Therefore, this P. kessleri strain is expected to be a good material to explore the mechanism of resistance to calcium ions stress for eukaryotic microbiology. [ABSTRACT FROM AUTHOR]

It has been proposed that an effective approach for predicting whether and how reef-forming corals persist under future climate change is to examine populations thriving in present day extreme environments, such as mangrove lagoons, where water temperatures can exceed those of reef environments by more than 3°C, pH levels are more acidic (pH < 7.9, often below 7.6) and O2 concentrations are regularly considered hypoxic (<2 mg/L). Defining the physiological features of these "extreme" corals, as well as their relationships with the, often symbiotic, organisms within their microbiome, could increase our understanding of how corals will persist into the future. To better understand coral-microbe relationships that potentially underpin coral persistence within extreme mangrove environments, we therefore conducted a 9-month reciprocal transplant experiment, whereby specimens of the coral Pocillopora acuta were transplanted between adjacent mangrove and reef sites on the northern Great Barrier Reef. Bacterial communities associated with P. acuta specimens native to the reef environment were dominated by Endozoicomonas , while Symbiodiniaceae communities were dominated by members of the Cladocopium genus. In contrast, P. acuta colonies native to the mangrove site exhibited highly diverse bacterial communities with no dominating members, and Symbiodiniaceae communities dominated by Durusdinium. All corals survived for 9 months after being transplanted from reef-to-mangrove, mangrove-to-reef environments (as well as control within environment transplants), and during this time there were significant changes in the bacterial communities, but not in the Symbiodiniaceae communities or their photo-physiological functioning. In reef-to-mangrove transplanted corals, there were varied, but sometimes rapid shifts in the associated bacterial communities, including a loss of "core" bacterial members after 9 months where coral bacterial communities began to resemble those of the native mangrove corals. Bacterial communities associated with mangrove-to-reef P. acuta colonies also changed from their original composition, but remained different to the native reef corals. Our data demonstrates that P. acuta associated bacterial communities are strongly influenced by changes in environmental conditions, whereas Symbiodiniaceae associated communities remain highly stable. [ABSTRACT FROM AUTHOR]

Aramid fibers are widely used in many cutting‐edge fields, including space, aviation, military, and electronics. However, their poor UV resistance and surface inertness seriously hinder their utilization, especially in harsh environments. Here, a dual‐layer ultrathin Al2O3–TiO2 coating with a thickness of 70–180 nm is fabricated on aramid fibers by a modified atomic layer deposition (ALD) method. The tenacity of ALD‐coated aramid fibers decreases only by ≈0.85% after exposure to intense UV light (4260 W m−2) under high temperature (>200 ℃) for 90 min, which equals to continuous exposure to sunlight for about 17 500 days. The as‐prepared aramid fibers also show excellent laundering durability, thermal and chemical stabilities. This work presents a green and damage‐free approach to achieve the highly anti‐UV aramid fibers without sacrificing their outstanding performance, which is expected to guide material design for future innovations in functional fibers and devices. [ABSTRACT FROM AUTHOR]

Commercial saturation divers are exposed to unique environmental conditions and are required to conduct work activity underwater. Consequently, divers' physiological status is shown to be perturbed and therefore, appropriate strategies and guidance are required to manage the stress and adaptive response. This study aimed to evaluate the daily energy expenditure (DEE) of commercial saturation divers during a 21-day diving operation in the North Sea. Ten saturation divers were recruited during a diving operation with a living depth of 72 metres seawater (msw) and a maximum working dive depth of 81 msw. Doubly labelled water (DLW) was used to calculate DEE during a 10-day measurement period. Energy intake was also recorded during this period by maintaining a dietary log. The mean DEE calculated was 3030.9 ± 513.0 kcal/day, which was significantly greater than the mean energy intake (1875.3 ± 487.4 kcal; p = 0.005). There was also a strong positive correction correlation between DEE and total time spent performing underwater work (r = 0.7, p = 0.026). The results suggested saturation divers were in a negative energy balance during the measurement period with an intraindividual variability in the energy cost present that may be influenced by time spent underwater. [ABSTRACT FROM AUTHOR]

It is established that green algae and land plants progressively colonized freshwater and terrestrial habitats throughout the Paleozoic Era, but little is known about the ecology of Paleozoic saline lakes. Here, we report lipid biomarker and petrographic evidence for the occurrence of a green alga as a major primary producer in a late Paleozoic alkaline lake (Fengcheng Formation; 309–292 Ma). A persistently saline and alkaline lacustrine setting is supported by mineralogical and lipid biomarker evidence alongside extremely enriched δ15Nbulk values (+16 to +24‰) for the lake depocenter. The prominence of C28 and C29 steroids, co‐occurring with abundant carotene‐derived accessory pigment markers in these ancient rocks, is suggestive of prolific primary production and elevated source inputs from haloalkaliphilic green algae. The high C28/C29‐sterane ratios (0.78–1.29) are significantly higher than the typical marine value reported for late Paleozoic rocks (<0.5) and thus are associated with certain groups of chlorophytes. Adaptation to such extreme lacustrine environments, aided by enhanced biosynthesis of certain cell membrane lipids, likely played an important role in the evolution and physiological development of ancient green algae. [ABSTRACT FROM AUTHOR]

Although persistent efforts have identified and characterized a few candidate genes and related biological processes with potential functions in the adaptation of many species to extreme environments, few works have been conducted to determine the genomic basis of adaptation in endangered livestock breeds that have been living in extreme conditions for more than thousands of years. To fill this gap, we sequenced the whole genomes of nine individuals from three Chinese native endangered cattle breeds that are living in high‐altitude or arid environments. Phylogenetic and evolutionary history analyses of these three and other six breeds showed that the genetic structure of the cattle populations is primarily related to geographic location. Interestingly, we identified pervasive introgression from the yak to Zhangmu cattle (ZMC) that cover several genes (e.g., NOS2, EGLN1 and EPAS1) involved in the hypoxia response and previously identified as positive selection genes in other species, which suggested that the adaptive introgression from yak may have contributed to the adaptation of ZMC to high‐altitude environments. In addition, by contrasting the breeds in opposite living conditions, we revealed a set of candidate genes with various functions from hypoxia response, water metabolism, immune response and body shape change to embryo development and skeletal system development, etc., that may be related to high‐altitude or arid adaptation. Our research provides new insights into the recovery and adaptation of endangered native cattle and other species in extreme environments and valuable resources for future research on animal husbandry to cope with climate change. [ABSTRACT FROM AUTHOR]

Human adaptation to extreme environments has been explored for over a century to understand human psychology, integrated physiology, comparative pathologies, and exploratory potential. It has been demonstrated that these environments can provide multiple external stimuli and stressors, which are sufficient to disrupt internal homeostasis and induce adaptation processes. Multiday hyperbaric and/or saturated (HBS) environments represent the most understudied of environmental extremes due to inherent experimental, analytical, technical, temporal, and safety limitations. National Aeronautic Space Agency (NASA) Extreme Environment Mission Operation (NEEMO) is a space-flight analog mission conducted within Florida International University's Aquarius Undersea Research Laboratory (AURL), the only existing operational and habitable undersea saturated environment. To investigate human objective and subjective adaptations to multiday HBS, we evaluated aquanauts living at saturation for 9–10 days via NASA NEEMO 22 and 23, across psychologic, cardiac, respiratory, autonomic, thermic, hemodynamic, sleep, and body composition parameters. We found that aquanauts exposed to saturation over 9–10 days experienced intrapersonal physical and mental burden, sustained good mood and work satisfaction, decreased heart and respiratory rates, increased parasympathetic and reduced sympathetic modulation, lower cerebral blood flow velocity, intact cerebral autoregulation and maintenance of baroreflex functionality, as well as losses in systemic bodyweight and adipose tissue. Together, these findings illustrate novel insights into human adaptation across multiple body systems in response to multiday hyperbaric saturation. [ABSTRACT FROM AUTHOR]

In extreme environments, the relationships between species are often exclusive and based on complex mechanisms. This review aims to give an overview of the microbial ecology of saline soils, but in particular of what is known about the interaction between plants and their soil microbiome, and the mechanisms linked to higher resistance of some plants to harsh saline soil conditions. Agricultural soils affected by salinity is a matter of concern in many countries. Soil salinization is caused by readily soluble salts containing anions like chloride, sulphate and nitrate, as well as sodium and potassium cations. Salinity harms plants because it affects their photosynthesis, respiration, distribution of assimilates and causes wilting, drying, and death of entire organs. Despite these life-unfavorable conditions, saline soils are unique ecological niches inhabited by extremophilic microorganisms that have specific adaptation strategies. Important traits related to the resistance to salinity are also associated with the rhizosphere-microbiota and the endophytic compartments of plants. For some years now, there have been studies dedicated to the isolation and characterization of species of plants' endophytes living in extreme environments. The metabolic and biotechnological potential of some of these microorganisms is promising. However, the selection of microorganisms capable of living in association with host plants and promoting their survival under stressful conditions is only just beginning. Understanding the mechanisms of these processes and the specificity of such interactions will allow us to focus our efforts on species that can potentially be used as beneficial bioinoculants for crops. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to explore the extent to which teamwork (developed either during an initial training phase or during a subsequent deployment phase) is influenced by the nature of the team's environment (extreme vs non-extreme) and the extent to which teamwork is one of the explaining mechanisms for team performance. Design/methodology/approach: Data was collected from 60 teams at 2 time-points: training phase in The Netherlands or Germany and deployment phase (in locations such as Afghanistan and Bosnia-Herzegovina). Findings: This study's results indicate that when teams consider working in extreme environments, they develop higher levels of teamwork as compared to teams expecting to work in non-extreme environments. These differences remain stable also during the deployment phase, such that teams operating in extreme environments will continue to have higher levels of teamwork as compared to teams operating in non-extreme environments. Originality/value: With this study, the authors contribute to the teamwork quality research stream by empirically studying how teamwork quality develops in unique military contexts such as extreme environments. Studies in such contexts are relatively rare. [ABSTRACT FROM AUTHOR]

Mobile genetic elements, including plasmids, drive the evolution of prokaryotic genomes through the horizontal transfer of genes allowing genetic exchange between bacteria. Moreover, plasmids carry accessory genes, which encode functions that may offer an advantage to the host. Thus, it is expected that in a certain ecological niche, plasmids are enriched in accessory functions, which are important for their hosts to proliferate in that niche. Puquio de Campo Naranja is a high-altitude lake from the Andean Puna exposed to multiple extreme conditions, including high UV radiation, alkalinity, high concentrations of arsenic, heavy metals, dissolved salts, high thermal amplitude and low O2 pressure. Microorganisms living in this lake need to develop efficient mechanisms and strategies to cope under these conditions. The aim of this study was to characterize the plasmidome of microbialites from Puquio de Campo Naranja, and identify potential hosts and encoded functions using a deep-sequencing approach. The potential ecological impact of the plasmidome, including plasmids from cultivable and non-cultivable microorganisms, is described for the first time in a lake representing an extreme environment of the Puna. This study showed that the recovered genetic information for the plasmidome was novel in comparison to the metagenome derived from the same environment. The study of the total plasmid population allowed the identification of genetic features typically encoded by plasmids, such as resistance and virulence factors. The resistance genes comprised resistances to heavy metals, antibiotics and stress factors. These results highlight the key role of plasmids for their hosts and impact of extrachromosomal elements to thrive in a certain ecological niche. [ABSTRACT FROM AUTHOR]

Microalgae are photosynthetic microorganisms that use sunlight as an energy source, and convert water, carbon dioxide, and inorganic salts into algal biomass. The isolation and selection of microalgae, which allow one to obtain large amounts of biomass and valuable compounds, is a prerequisite for their successful industrial production. This work provides an overview of extremophile algae, where their ability to grow under harsh conditions and the corresponding accumulation of metabolites are addressed. Emphasis is placed on the high‐value products of some prominent algae. Moreover, the most recent applications of these microorganisms and their potential exploitation in the context of astrobiology are taken into account. [ABSTRACT FROM AUTHOR]

This is a review of microbes which live in extreme environments. We focused on natural hot springs with high temperatures and/or acidic environments. Rod shaped bacterium, Bacillus acidocaldarius with spores from Kuroyu, Akita Prefecture were cultured at 55°C under acidic conditions. Sulfur-oxidizing bacteria were cultured from Yunohanazawa, Kanagawa Prefecture. These bacteria were associated with the quality of sulfur in the springs' flow. Irregularly formed archaea were cultured at 70°C under acidic condition from a hot spring pool in the Hakone-Oowakudani geothermal area. The strain was a new species, which was then named Metallosphaera hakonensis. Then, bacterial and archaeal community structures in Japanese hot springs were revealed by 16 rRNA clone library analyses. It has been noted that only a small fraction (<1%) of the microorganisms found in nature can be cultured using traditional cultivation methods. Therefore, a culture independent method, 16S clone library analysis is useful method to reveal the bacterial and archaeal communities. For example, Satoh et al analyzed and compared the 16S rRNA gene compositions and environmental factors of four distinct solfataric acidic hot springs in Kirishima, Japan. As a result, species compositions and biodiversity were clearly different between the ponds showing different temperatures and dissolved elemental concentrations. Moreover, hot spring microalgae such as cyanobacteria, green algae, diatoms and red algae were examined. They live in about 20°C to 80°C, and in acid (pH2-3), neutral (pH6-7), and week alkaline (pH8-9) conditions. Unicellular red algae Cyanidium caldarium, Galdieria sulphuraria, and diatom Pinnularia sp. live in acid hot springs such as Noboribetsu hot springs, Hokkaido and Kusatsu hot springs, Gunma prefecture. Cyanobacteria Mastigocladus sp., Phormidium sp., and Oscillatoria sp. live in neutral and weak alkaline hot springs such as Shima hot springs, Gunma prefecture, Tsurunoyu hot springs, Akita prefecture, and Atagawa hot springs, Shizuoka prefecture. Micro algae capable of photosynthesis form the hot spring ecosystem among bacteria, protozoa and other microorganisms. [ABSTRACT FROM AUTHOR]

Despite increasing environmental variability within marine ecosystems, little is known about how coral reef fish species will cope with future climate scenarios. The Arabian/Persian Gulf is an extreme environment, providing an opportunity to study fish behaviour on reefs with seasonal temperature ranges which include both values above the mortality threshold of Indo-Pacific reef fish, and values below the optimum temperature for growth. Summer temperatures in the Gulf are comparable to those predicted for the tropical ocean by 2090–2099. Using field observations in winter, spring and summer, and laboratory experiments, we examined the foraging activity, distance from refugia and resting time of Pomacentrus trichrourus (pale-tail damselfish). Observations of fish behaviour in natural conditions showed that individuals substantially reduced distance from refugia and feeding rate and increased resting time at sub-optimal environmental temperatures in winter (average SST = 21 °C) and summer (average SST = 34 °C), while showing high movement and feeding activity in spring (average SST = 27 °C). Diet was dominated by plankton in winter and spring, while fish used both plankton and benthic trophic resources in summer. These findings were corroborated under laboratory conditions: in a replicated aquarium experiment, time away from refugia and activity were significantly higher at 28 °C (i.e. spring temperature conditions) compared to 21 °C (i.e. winter temperature conditions). Our findings suggest that P. trichrourus may have adapted to the Arabian/Persian Gulf environment by downregulating costly activity during winter and summer and upregulating activity and increasing energy stores in spring. Such adaptive behavioural plasticity may be an important factor in the persistence of populations within increasing environmentally variable coral reef ecosystems. [ABSTRACT FROM AUTHOR]

Fishes exhibit greater species diversity than any other group of vertebrates. They are found in most bodies of water, including those that pose extreme challenges, such as sulfide springs, rivers contaminated with heavy metals and organic pollutants, and caves without light. Adaptation to these extreme environments usually occurs rapidly, which has stimulated much interest in uncovering the genetic basis of such rapid adaptation. Since the sequencing of the zebrafish genome in 2001, rapid development of high-throughput sequencing technology has facilitated the additional sequencing of ~ 210 ray-finned fish genomes to date. As a result of this wealth of resources, much attention has been focused on the genetic basis of adaptation in fishes, particularly in extreme environments. The goal of this review is to summarize recent advances in fish genomics, with a specific focus on the use of genomic data to understand the genetic basis of adaptation to extreme environments in fishes. The results highlight that fishes often adapt to extreme environments through phenotypic and physiological changes that have a confirmed or inferred genetic basis. Moreover, such changes are usually rapid and repeated when parallel adaptation to similar extreme environments occurs. Specifically, parallel genetic changes are usually observed at both the intra- and interspecific level. The advances in fish genomics provide the opportunity to understand how evolutionary changes feed back into ecosystems that are facing extreme environmental changes, as well as to advance our understanding of the repeatability and predictability of evolutionary response (of fishes) to extreme environmental changes. [ABSTRACT FROM AUTHOR]