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Copyright of Chinese Journal of High Pressure Physics is the property of Chinese Journal of High Pressure Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The wound-field doubly salient machine (WFDSM) is a generating system core assembly. Its condition monitoring and early fault diagnosis are key to improving system reliability. This study proposes a fault diagnosis method based on multi-signal mixed domain fusion at the feature level and genetic algorithm improved XGBoost (GA-XGBoost). First, low-pass noise reduction, singular value decomposition noise reduction, and other signal pre-processing are applied to the current and vibration signals of early inter-turn short-circuit faults. Second, the time domain, frequency domain, and entropy features of the current signal, along with the time domain features of the vibration signal, are extracted, together forming a diagnostic feature set. Then, the feature set is put into the GA-XGBoost model. The results show that the proposed method of feature fusion achieves an accuracy of 99.3%. Thus, the multi-signal mixed domain fusion has stronger signal characteristic expression ability. In addition, the GA-XGBoost model achieves better generalizability and higher accuracy in the small-scale samples of WFDSM faults. The experimental results demonstrate that this method can effectively diagnose various conditions and also has strong anti-interference capability under extreme conditions. [ABSTRACT FROM AUTHOR]

The last decades have witnessed the rapid growth of hydrogel bioelectronics. Traditional hydrogels face challenges when working under extreme conditions, causing a loss of stabilities and functionalities. This review provides a systematic overview of hydrogels capable of working under extreme conditions, with a focus on their applications in bioelectronic systems. These hydrogels are summarized into categories of anti‐mechanical damage, anti‐detachment, anti‐swelling, anti‐freezing, and anti‐foreign body response. Strategies including material development and structural design that can endow hydrogels with the above extreme properties are introduced. Finally, current challenges and new opportunities in developing extreme hydrogel bioelectronic devices and systems are discussed. [ABSTRACT FROM AUTHOR]

Extreme conditions, such as the COVID-19 pandemic and the Russian attack on Ukraine, cause major disruptions, with teachers struggling to uphold educational provision. The study presented here aimed to substantiate and experimentally confirm the effectiveness of providing teachers with psychological support in extreme situations in order to optimise the balance of the psychological and pedagogical components in their professional activity. Regular teacher training in Ukraine includes a standard course, "Pedagogy and Psychology", which provides teachers with basic knowledge of pedagogical psychology. Building on this basic course, the authors of this article developed an advanced training course entitled "Psychological support for teachers in extreme conditions". A supplementary course of this kind is especially important in extreme conditions such as a war, as it is designed to clarify the methods of professional activity in practice, based on updated and expanded psychological knowledge. The authors piloted the course with a group of 190 teachers (80% female, 20% male) from a wide range of backgrounds in terms of age, years of experience, subject field, type of institution etc. They compared the effect with a control group of 190 teachers (85% female, 15% male) who had only taken the basic course. Findings of the pilot study suggest that awareness of the importance of psychological knowledge in education increases in proportion to the teacher's experience. A key issue is the teachers' motivation to engage in psychological training: they must clearly understand how and where they can apply the acquired psychological knowledge in their professional activity. Having conducted their pilot study in conditions of martial law in Ukraine, the authors conclude that improving teachers' psychological readiness for extreme conditions not only preserves the quality of the educational process, but also helps to preserve the psyche of students in conditions of war. [ABSTRACT FROM AUTHOR]

The extreme conditions severely constrain the dynamic characteristics of aircraft landing gear retraction mechanism (ALGRM). This paper proposes a dynamic modeling and analysis method for ALGRM considering the coupling effects of extreme conditions such as clearance joints, flexible rods, and salt spray corrosion. Firstly, the mathematical model for clearance joint and flexible rod is established and the dynamic model of ALGRM considering clearance joints and flexible rods is formulated based on Lagrangian equation. Furthermore, the salt spray corrosion model for clearance joint is developed using COMSOL simulation software. Finally, the effects of different temperatures and relative humidities on the corrosion depth of clearance joint and the dynamic characteristics of ALGRM under the coupling effects of extreme conditions are investigated. The results have found that the impact of extreme conditions on dynamics of system cannot be ignored. This study not only provides a theoretical foundation for predicting the dynamic characteristics of ALGRM under extreme conditions but also offers insights for the optimization design and corrosion protection efforts of landing gear. [ABSTRACT FROM AUTHOR]

Sleep and its quality are vital for the normal functioning of the human body. Ship crews are exposed to a range of occupational, social and climatic stressors that adversely affect sleep quality. It is one of the leading indicators of possible health, psychological or emotional problems. The Sleep Quality Questionnaire (PSQI) enables the subject to make a subjective assessment of the factors affecting their sleep and its quality in general. This questionnaire is being applied in Bulgaria for the first time. Volunteers from the ship's crew of the Scientific Research Ship "St. Cyril and Methodius" participating in the first voyage to Antarctica were studied. Unique opportunity to track sleep changes occurring under the influence of extreme conditions. The results obtained show that the questionnaire takes into account the changes that occurred in the crew's sleep quality during the voyage. The data obtained from the pre-departure and post-return questionnaires are compared. Statistical analyses using Wilcoxon's test revealed statistically significant differences between the two groups of data. Statistically significant correlations were observed between the level of anxiety and depression measured by Tsung's test and certain statements from the Sleep Assessment Questionnaire. This provides a rationale for proposing the current instrument for application in the maritime industry. [ABSTRACT FROM AUTHOR]

Shellfish cultivation is a sustainable method of providing human food and can help remove large amounts of CO2 from the atmosphere. Over the last two decades, longline-based structures have dominated farming systems. So far, the innovative technologies for open-ocean shellfish farming remain stagnant and need to be developed. As such, this paper preliminarily studies the operation and survivability abilities of an innovative shellfish farm under extreme wave conditions. To that end, an efficient numerical scheme with a robust implicit finite element method is established. First, the numerical modeling of a single module of the shellfish farm is conducted and the numerical results are verified against physical model tests. Then, the numerical modeling is implemented in a full-scale shellfish farm containing nine floating rafts with suspended lantern nets in a 3×3 configuration exposed to extreme wave conditions. Different angles of wave attack and shellfish rafts with and without lantern nets are fully considered, allowing an assessment of the operation and survivability abilities of the shellfish farm under extreme wave conditions in various situations. The results highlight that the angle of wave attack significantly affected the energy absorption of the mooring system. Moreover, non-linear instability such as subharmonics, which existed in the motion dynamics, can be manipulated to avoid resonant motions. This study provides insights into the evaluation of the safety design of a shellfish farm at both operational and survivability levels. The numerical method can also model other advanced offshore marine structures with multi-modules, such as floating bridges, airports, and even floating energy islands. [ABSTRACT FROM AUTHOR]

Mechatronic simulators for psychophysical preparation and training of personnel are presented. [ABSTRACT FROM AUTHOR]

This work is aimed at a comprehensive solution to the problem of reliable and safe operation of a transport energy system with a high energy concentration based on a universal energy carrier - cryogenic liquid hydrogen. The article discusses the possibility of using various methods and techniques to assess the reliability of machines and equipment operated in emergency situations and extreme conditions. The obtained results are analyzed. Currently, the oil and gas complex pays great attention to the development of hydrogen technologies, as well as hydrogen energy in connection with the relevance of the Climate Agenda. In this regard, hydrogen energy facilities are of the greatest interest: cryogenic hydrogen reservoirs, cryogenic hydrogen pipelines, cryogenic oxygen reservoirs and cryogenic oxygen pipelines, as well as cryogenic reservoirs and pipelines for storing process nitrogen gas. An important role for global energy exchange is played by LH 2 tankers for transporting cryogenic hydrogen. For example, Australia and Japan built the first LH 2 tanker to transport hydrogen from Australia to Japan. In addition, another 85 LH 2 tankers are expected to be built. After transportation, cryogenic hydrogen is stored in cryogenic hydrogen storages, usually also representing cryogenic hydrogen tanks with piping in the form of cryogenic pipelines, as well as cryogenic nitrogen tanks for storing process nitrogen gas. Further, hydrogen is used in road transport, aviation, ship fleet, industry, and energy. The main elements of mobile, stationary and airborne hydrogen storage systems are under critical loads and are in the area of increased study and attention. In this regard, we considered the functions of changing the main operational characteristics, made proposals on the possibility of predicting the development of accumulated faults and proposals for ensuring safety and extending the life of objects, taking into account the determination of local and integral damage to cryogenic tanks and pipelines. Project for the creation of a main cryogenic hydrogen pipeline from Azerbaijan to Europe across the Adriatic Sea. [Display omitted] [ABSTRACT FROM AUTHOR]

Glass and glass ceramics are very functional materials, albeit their structural complexity. Their relevance ranges from fundamental science problems in the fields of physics, chemistry, and geoscience, to applications in health areas, engineering, or technological matters that require high performance. Enhancing our understanding of these materials' performance and refining sample preparation methods remains paramount in this field. Synchrotron facilities offer a suite of powerful techniques for the detailed characterization of glasses and glass ceramics. These methods provide valuable insights into their atomic and molecular structure, phase transformations, mechanical behavior, and thermal properties, ultimately contributing to the development of improved materials for a wide range of applications. In‐depth investigations conducted under extreme conditions of pressure and temperature have yielded pivotal insights into densification mechanisms, phase transitions, crystallization kinetics, and their consequential macroscopic properties. The emergence of fourth‐generation synchrotrons brings in a wave of novel experimental possibilities that may exert a profound influence on this field in the coming decade. In this study, we unveil a selection of the remarkable capabilities now accessible to researchers at the Brazilian Synchrotron Light Source—Sirius, within the realm of extreme methods of analysis (EMA) beamline for investigating vitreous systems under extreme conditions. [ABSTRACT FROM AUTHOR]

With the global expansion of geothermal energy, accurate prediction of pressure and temperature during drilling has become essential for ensuring the safety and efficiency of geothermal wells. Traditional numerical methods, however, often struggle to handle complex wellbore environments due to their high data demands and limited computational accuracy. To address these challenges, this paper introduces an innovative predictive model based on Physics-Informed Neural Networks (PINNs). By integrating physical laws with deep learning, the model theoretically surpasses the limitations of conventional methods. Trained on pressure and temperature data from a geothermal well in the Xiong'an area, the model demonstrates exceptional accuracy and robustness. Additionally, the model was rigorously tested under extreme wellbore conditions, showcasing its strong generalization capabilities. The findings suggest that PINNs offer a highly advantageous solution for geothermal drilling, with significant potential for practical engineering applications. [ABSTRACT FROM AUTHOR]

We present, in this overview article, the main features of the ID15B beamline on the new ESRF Extremely Bright Source (EBS). The ID15B beamline was fully reconstructed in 2015, considering the new capabilities of the future EBS machine. We will introduce the ID15 project, the ID15B undulator X-ray source, the optical scheme and the experimental hutch. The beamline ID15B is mostly dedicated to the determination of structural properties of solids at high pressure using angle-dispersive diffraction with diamond anvil cells. We present different selected research examples illustrating the capabilities of this instrument. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) often face performance limitations under stringent conditions, such as low temperatures and overcharge/overdischarge scenarios, primarily due to the inadequacies of cathode materials. Nickel hexacyanoferrate (NiHCF) has emerged as a promising candidate due to its zero-strain ion-insertion characteristic and efficient ionic diffusion pathways. However, its practical application is hindered by inadequate ionic and electronic conductivity. In this study, we address these challenges by enhancing the electronic conductivity of NiHCF through the incorporation of multi-walled carbon nanotubes (MWCNTs). This strategic integration not only leverages NiHCF’s zero-strain ion-insertion property but also significantly improves electron and ion transport. As a result, the modified NiHCF/MWCNT composite demonstrates superior electrochemical performance, exhibiting enhanced robustness and efficiency, making it suitable for large-scale energy storage applications. Under a current density of 10 A g−1 at 25℃, the NiHCF/MWCNT composite maintains stable cycling for up to 5000 cycles, with a notable specific capacity of 59.33mAhg−1. Even at −20 ℃, it continues to deliver robust cycling for 5000 cycles at 10 A g−1. Remarkably, after overcharging to 4.25 V and overdischarging to 1.2 V at both 25 ℃ and −20 ℃, the NiHCF/MWCNT electrode still maintains robust cycling performance. This advancement not only addresses the current limitations of electrode materials under extreme conditions but also offers a scalable and practical approach to improving sustainable energy storage technologies.

The wound-field doubly salient machine (WFDSM) is a generating system core assembly. Its condition monitoring and early fault diagnosis are key to improving system reliability. This study proposes a fault diagnosis method based on multi-signal mixed domain fusion at the feature level and genetic algorithm improved XGBoost (GA-XGBoost). First, low-pass noise reduction, singular value decomposition noise reduction, and other signal pre-processing are applied to the current and vibration signals of early inter-turn short-circuit faults. Second, the time domain, frequency domain, and entropy features of the current signal, along with the time domain features of the vibration signal, are extracted, together forming a diagnostic feature set. Then, the feature set is put into the GA-XGBoost model. The results show that the proposed method of feature fusion achieves an accuracy of 99.3%. Thus, the multi-signal mixed domain fusion has stronger signal characteristic expression ability. In addition, the GA-XGBoost model achieves better generalizability and higher accuracy in the small-scale samples of WFDSM faults. The experimental results demonstrate that this method can effectively diagnose various conditions and also has strong anti-interference capability under extreme conditions.

Applied techniques and some results of studies the higher nervous activity (HNA) of the people, their psychophysiological functions (PFF) by Ukrainian scientists and doctors were described, as well as influences of extreme conditions on HNA. Aim. Results of the influence of extreme mountain conditions at high altitudes (hypoxia, etc.) demonstration and further research of changes in the psychophysiological functions of the brain under these conditions; description of the developed methods of professional selection. Methods. Comparative analysis of a large number of the data from experiments and observations. Physical, mathematical, program modeling. Methods of HNA, brain research: electroencephalography, diagnosis of personal neurodynamic features, etc. Three methods of PFF research: parameters of the neurodynamic level, parameters of the neuropsychological level, and personal specifics. The adapted questionnaire scheme (QS) based on Cattell's 16-factor personality tests was applied. Results. The influence of hypoxia and other factors of mountain conditions on HNA were studied deeply. The results were presented. Also, there were presented results of registered changes of EEG in such extreme conditions. The influence of a number of stress factors in extreme conditions (hypoxia, etc.) has been demonstrated. Some basic methods of HNA researches used in such conditions were described as well as results of investigations of individual typological features of the nervous systems were presented. Methods for human psychophysiological functions studying were described. Studies of human personal characteristics were described in details. Data recorded by the PNN-3 device were taken for the diagnosis of personal neurodynamic features. The parameters of the neuropsychological level were determined using the following methods: "triangles" (the level of development of short-term visual memory), "instrument scales" (working memory, attention functions, etc.), and "red and black tables" (allocation and switching of attention). Personality structures, features, and types of behavior of operators in stressful situations were estimated basing on adapted QS by Cattell. Mathematical models of the reliability of human nervous system functioning under extreme conditions were developed. Conclusions. The obtained results were taken as the basis for the developed professional selection methods for special contingents, pilots, operators, etc. Physical, mathematical, and program models of the reliability of the human nervous system functioning in these conditions were proposed.

The war carried out in extreme conditions requires exceptional training involving a degree of difficulty far above most situations encountered on the battlefield, because, on the one hand, the fighter performs missions in conditions totally different from those of a classic warfare and, on the other on the other hand, he must face special physical and mental demands. In order to be able to meet all the demands imposed by the hardness and complexity of these areas of action, it is necessary for the fighters who act in such environments to have a versatile training. Along with the intellectual, technical, tactical and psychological training, the physical component of the training plays a basic role, which in my opinion constitutes a pivot of all the other components of the training. In the paper, along with the demands and rigors of extreme environments, there are presented a series of benefits of an exceptional physical training which, by ensuring a solid motor capacity, also ensures a part of the mental preparation for the fight, elements that are the basis of the training and consolidation of specific combat aptitudes and skills.

Colorants in molasses wastewater, such as melanoidins and phenols pigment, are rarely degraded through conventional biological processes. Decolorization is the focus of molasses wastewater treatment. Unfortunately, enzymatic decolorization is severely restricted by extreme conditions. In the present study, screened thermo-acidophilic laccase and glucose oxidase were immobilized on a cheap-modified bagasse cellulose carrier. The immobilized dual thermo-acidophilic enzymes exhibited a decolorization yield of 96.81% on untreated molasses wastewater at 80 °C (pH 4.5), which was higher than all other yields reported. The immobilized enzymes eliminated 60.24% of colorants for 7 days when 10% of fresh untreated molasses wastewater was added each day. Glucose oxidase was the most critical enzyme in decolorization, reducing sugar apparently influenced decolorization. The generated hydrogen peroxide oxidized melanoidins and other pigments, leading to decolorization. Accordingly, this study provided new insight into in decolorization of molasses wastewater under extreme conditions and analyzed the underlying mechanism. [ABSTRACT FROM AUTHOR]

Climate change and the variable extreme weather conditions that today's agricultural producers are dealing with represent some of the most important issues in food production. Nowadays, weather patterns are increasingly unpredictable, characterized by frequent fluctuations in temperature, precipitation, and extreme weather events. As a result, there is an increasing demand for scientists to develop more resilient and tolerant crop cultivars. Plant breeders must become creative and utilize all available resources to create modern high-yielding and widely adapted cultivars to help agriculture grow and thrive amidst the emerging changes. Forage legumes, due to their beneficial characteristics, are among the crops that can contribute to mitigating the consequences of climate change. Furthermore, what certainly does not contribute to weather conditions is the erosion of plant genetic material, which has been caused by the modernization of agriculture and the selection of the best cultivars with desirable traits over many years. Crop wild relatives (CWRs) and landraces represent plant genetic materials rich in novel gene variants that contain traits for resistance and tolerance to different climatic conditions. To expand the genetic base of cultivars and mitigate the consequences of climate change, breeders are increasingly utilizing pre-breeding methods. These methods include all the activities connected to the identification of desirable genes and traits from un-adapted materials, such as CWRs, and the transformation of these traits to an intermediate set of materials that can be used for creating new cultivars. This review paper will cover the pre-breeding process, including its components, and the resistance and/or tolerance of the CWRs and landraces of forage legumes to different extreme environmental conditions. [ABSTRACT FROM AUTHOR]

Introduction of Th into synthetic disordered fluorite-type Gd2Zr2O7 induces a transition to an ordered pyrochlore-type phase at a Th concentration of 10 % at the Gd site (Gd1.8Th0.2Zr2O7 composition). The degree of order of the fluorite-type phase reaches 50 % for a Th concentration of 25 % (Gd1.5Th0.5Zr2O7 composition). Upon application of high pressure, the Gd2Zr2O7 phase retains the fluorite-type structure until 33 GPa (K0 = 167(1) GPa), where it undergoes reversible amorphization. The Gd1.7Th0.3Zr2O7 phase was found to be stable up to at least a pressure of 25 GPa (K0 = 169(3) GPa). Upon heating to Tmax of 1135 K, the Gd2Zr2O7 phase retains its disordered fluorite-type structural arrangement (α = 3.03 × 10−5 K−1). The excellent stability of the Gd2−xThxZr2O7 phases under extreme conditions of temperature and pressure makes Gd2Zr2O7 a promising candidate as a host matrix for radioactive elements for safe long-term underground storage of nuclear waste. [ABSTRACT FROM AUTHOR]

The history of tribology research in China is reviewed briefly in this paper. Developmental stages are divided, and some memorable events in tribology research in China are introduced from my personal view. The statistics of the funding from the National Natural Science Foundation of China (NSFC) and of published research papers on tribology in the Web of Science database are analyzed to better understand the state-of-the-art of tribology research in China, including most active research institutions and fields. In addition, major research contents are obtained according to keywords, and main achievements in tribology related to lubrication, lubricating materials, superlubricity, wear, biotribology and bionictribology, nanotribology, surface engineering, tribology in extreme conditions, and machine elements, particularly in recent years, are summarized. This paper shows that tribology is a rapidly developing discipline in China and has been one of the most important contributors to world tribology.

The Vendée Globe is a non-stop, unassisted, single-handed round the world sailing race. It is regarded as the toughest sailing race, requiring high cognitive functioning and constant alertness. Little is known about the amount of sleep restriction and nutritional deficit experienced at sea and effects that fatigue have on sailors' performance. This report aimed to investigate these aspects by monitoring one of the female participants of the latest Vendée Globe. Sleep, food intake and stress were self-reported daily using specific app. Cognitive assessments were digitally completed. Heart rate and activity intensity were measured using a wrist-worn wearable device. Mean self-report sleep duration per 24 h was 3 hours 40 minutes. By the end of the 95 race days, the sailor reached a caloric deficit of 27,900 kcal. On average, the sailor spent 50 minutes per day in moderate-to-vigorous activity. Cognitive assessments did not show any effect of fatigue or stress on completion time or performance. Recent technological and communication advancement for offshore sailors, enabled continuous data to be monitored in near real time, even from the Southern Ocean. Moving forward this will enable greater understanding of when sailors will be at risk of poor decision making, illness or injury. [ABSTRACT FROM AUTHOR]

The increasing worldwide demand for antimicrobial agents has significantly contributed to the alarming rise of antimicrobial resistance, posing a grave threat to human life. Consequently, there is a pressing need to explore uncharted environments, seeking out novel antimicrobial compounds that display exceptionally efficient capabilities. Hot springs harbor microorganisms possessing remarkable properties, rendering them an invaluable resource for uncovering groundbreaking antimicrobial compounds. In this study, thermophilic bacteria were isolated from Mahallat Hot Spring, Iran. Out of the 30 isolates examined, 3 strains exhibited the most significant antibacterial activities against Escherichia coli and Staphylococcus aureus. Furthermore, the supernatants of the isolated strains exhibited remarkable antibacterial activity, displaying notable resistance to temperatures as high as 75 °C for 30 min. It was determined that the two strains showed high similarity to the Bacillus genus, while strain Kh3 was classified as Saccharomonospora azurea. All three strains exhibited tolerance to NaCl. Bacillus strains demonstrated optimal growth at pH 5 and 40 °C, whereas S. azurea exhibited optimal growth at pH 9 and 45 °C. Accordingly, hot springs present promising natural reservoirs for the isolation of resilient strains possessing antibacterial properties, which can be utilized in disease treatment or within the food industry. [ABSTRACT FROM AUTHOR]

Copyright of Logos: A Journal, of Religion, Philosophy Comparative Cultural Studies & Art (08687692) is the property of Logos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Contacting bodies in extreme environments are prone to severe wear and failure due to friction and seizure, which are associated with significant thermal and mechanical loads. This phenomenon greatly impacts the economy since most essential components encounter these challenges during machining, an unavoidable step in most manufacturing processes. In machining, stress can reach 4 GPa, and temperatures can exceed 1000 °C at the cutting zone. Severe seizure and friction are the primary causes of tool and workpiece failures. Liquid lubricants are popular in machining for combatting heat and friction; however, concerns about their environmental impact are growing, as two-thirds of the 40 million tons used annually are discarded and they produce other environmental and safety issues. Despite their overall efficacy, these lubricants also have limitations, including ineffectiveness in reducing seizure at the tool/chip interface and susceptibility to degradation at high temperatures. There is therefore a push towards solid lubricants, which promise a reduced environmental footprint, better friction management, and improved machining outcomes but also face challenges under extreme machining conditions. This review aims to provide a thorough insight into solid lubricant use in machining, discussing their mechanisms, effectiveness, constraints, and potential to boost productivity and environmental sustainability. [ABSTRACT FROM AUTHOR]

The unique diffraction geometry of ESRF beamline ID06-LVP offers continuous static 2D or azimuthally resolving data collections over all accessible solid angles available to the tooling geometry. The system is built around a rotating custom-built Pilatus3 CdTe 900k-W detector from Dectris, in a configuration equivalent to three butted 300k devices. As a non-standard geometry, here the method of alignment, correction and subsequent integration for any data collected over all solid angles accessible, or over any azimuthal range contained therein, are provided and illustrated by parameterizing and extending existing pyFAI routines. At 1° integrated intervals, and typical distances (2.0 m), the system covers an area of near 2.5 m2 (100 Mpx square equivalent), to 0.65 Å resolution, at 53 keV from a total dataset of some 312 Mpx. Standard FWHMs of SRM660a LaB6 vary from 0.005° to 0.01°, depending on beam size, energy and sample dimensions, and are sampled at an elevated rate. The azimuthal range per static frame ranges from

There is a high risk of dam breakage in tailing reservoirs under extreme conditions. Once a dam breaks, it causes serious pollution to the surrounding ecological environment. To explore the effects of a tailings dam break under extreme conditions (flood conditions, drainage failure, flood discharge failure, and dam saturation), the mechanism underlying an overtopping dam break must be accurately understood. In this study, fine-grained tailings and perlite were selected to create composite model sand, and a prototype tailing reservoir was restored at a scale of 1:200. Furthermore, the dam-break process and results were analyzed and summarized by performing an overtopping dam-break test on the tailing reservoir under extreme conditions. The results show that the tailing discharge process has a high sand content, strong sand-carrying capacity, and high speed. The amount of model sand discharge accounted for 15.13% of the total storage capacity, and the amount of tailings deposition in the downstream area accounted for 95.21% of the discharge, which were both greater than the results of similar physical model tests and actual tailings dam failure accidents. An overtopping dam break in a tailing pond is a progressively destructive process. The dam break mechanism can be divided into two stages: prior breach penetration and subsequent breach horizontal expansion. In the process of a tailings dam break, the motion state of the tailings particles is transformed between the bed-load and suspended-load movement states. These results can provide important reference for the reinforcement of mine management and the formulation of preventive measures, which are essential to improving the safety of tailings reservoirs and protecting the ecological environment. [ABSTRACT FROM AUTHOR]

The investigation of the features of laser control over the state of nanoscale objects in solid materials is an urgent task of condensed matter physics. We experimentally established the potential for the simultaneous enhancement of hardness and resistance to surface cracking in a titanium alloy due to selective laser irradiation. The regularities of selective heating near nanopores and the influence of the nanopore system on the features of isotherm propagation have been revealed. A physical model is proposed for the healing of nanopores situated in the surface layer of the sample. According to this model and as a result of laser irradiation and laser plasma, a brief transition of the material surface to extreme conditions is initiated. [ABSTRACT FROM AUTHOR]

Effective thermal superinsulation in extremely high temperatures (EHT) is crucial for aerospace, industrial, and civilization activities. However, current strategies relying on ceramic materials face limitations due to their high thermal conductivity and brittleness in specific conditions. In this study, a feasible and scalable method for synthesizing a flexible, lightweight, and transformable fire‐reborn silica‐alumina hybrid ceramic aerogel (FR‐SACA) is presented, which is achieved by rearranging silica aerogel microparticles and Al2O3 ceramic fibers using a self‐sacrifice polymer, resulting in a bio‐inspired bird nest structured FR‐SACA. The SACA exhibits exceptional properties, including an ultra‐low density of 0.01 g cm−3, a low thermal conductivity of 0.029 W m−1 K−1, and a reversible compression of up to 80%. Notably, a 20 mm‐thick FR‐SACA demonstrates a remarkable temperature reduction of 1179.6 °C when exposed directly to a 1300 °C flame, suggesting its potential as a thermal superinsulation material in EHT environments. Furthermore, the transformability of SACA enables in situ fabrication on surfaces with diverse heteromorphic structures, such as flat, bent, and angled shapes, thereby providing thermal superinsulation for various constructions. The Phoenix Nirvana process opens up new possibilities for synthesizing ceramic aerogels with desirable flexibility and adaptive properties, facilitating effective thermal management under extreme conditions. [ABSTRACT FROM AUTHOR]

The magnetic structure of chromium arsenide CrAs is studied with neutron powder diffraction at ambient pressure in the temperature range 1.5–300 K as well as with neutron single‐crystal diffraction at 2 K and 0.12 GPa. The material undergoes an anti‐isostructural phase transition at TN = 267 K and atmospheric conditions, in which both orthorhombic phases have the same space‐group symmetry (Pnma, Z = 4) but different distortions of the parent hexagonal structure of the NiAs type (P63/mmc, Z = 2). The magnetic structure below TN is incommensurate with the propagation vector k = (0, 0, kc). At ambient pressure, the component kc decreases from kc = 0.3807 (7) at 260 K to kc = 0.3531 (6) at 50 K. Below this temperature, it is basically constant. With increasing pressure at 2 K, kc is also constant within standard uncertainties [kc = 0.353 (2)]. For the analysis of the magnetic structure, a group‐theoretical approach based on the space group of the nuclear structure and its subgroups is used. To avoid falling into false minima in the refinements, a random search for magnetic moments in the models is implemented. In the literature, the magnetic structure has been determined on the basis of powder diffraction data as a double helix propagating along the c axis. Although this double‐helical model leads to satisfactory agreement factors for our powder data, it does not reproduce the intensities of the magnetic satellite reflections measured on single‐crystal data in a satisfactory way and can therefore be discarded. Instead, several other models are found that lead to better agreement. Each of them is spiral‐like with directional components in all three directions and with no spin‐density wave character that would cause a non‐constant magnetic moment. In all these models, the ordering of the spins is neither a pure helix nor a pure cycloid. Instead, the unit vectors of the spin rotation planes make an angle α, 0° < α < 90°, with respect to the c* direction. The model in superspace group P21.1′(α0γ)0s yields the best agreement factors in the refinements of the neutron single‐crystal and powder diffraction data. This model is unique as it is the only one in which all the magnetic moments rotate with the same chirality. [ABSTRACT FROM AUTHOR]

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The design of a river-basin-specific flood hydrograph generator based on gauge records enables the generation of synthetic flood hydrographs for the dimensioning of hydraulic structures. Based on selected flow time series, flood waves can be described using four parameters based on flood characteristic simulations, as described by Leichtfuss and Lohr (1999). After successfully adapting suitable distribution functions, dependencies in the load structure are quantified in the next step using copula functions. This newly developed approach builds on the procedure proposed by Bender and Jensen (2012), which assumes hydrological independence. Using copula functions results in increased accuracy in the extended flood characteristic simulation. Moreover, considerable enhancements are achieved through the utilization of genetic algorithms, wherein the descending branch of the flood hydrograph is adjusted by employing an additional variable factor. Subsequently, any number of synthetic flood hydrographs can be generated by combining these parameters. In keeping with the principle of Monte Carlo simulation, a sufficiently high number of synthetic events results in extreme conditions with a low probability of occurrence being reliably represented. Hence, this endeavor has the potential to enhance result reproducibility and prediction quality. As a result, this expanded approach can be employed to provide dependable assessments regarding inflows aimed at optimizing reservoir capacity, for instance. [ABSTRACT FROM AUTHOR]

This study aimed to explore the influence of extreme factors on the body's adaptive capabilities and neurodynamic functions in military personnel. The research involved 26 cadets with an average age of 19.7 years; the study was conducted at an altitude of 1100 m above sea level. The cadets engaged in a 5-kilometer forced march at an air temperature of -15°C, with data measured using a Garmin Fenix 6S Pro watch. The adaptive capabilities of the functional state were assessed using the "MPFI rhythmograph-1" system and EasyHRV software, while sensorimotor functions were evaluated using the "DIAGNOST-1" computer system. Statistical analysis, employing non-parametric methods, was applied to the collected data. The results indicate that extreme factors significantly influenced the adaptation capabilities of the cadets. According to the median, the time of passing the distance was 29 min 23 s with an average heart rate of 159.5 bpm and an energy expenditure of 333.5 kcal. Duration of high-intensity activity was 12.28 min in the heart rate zone of 162-181 bpm-1, and zero time was spent in the maximum heart rate zone. The latter may be related to the impact of temperature conditions on the intensity of physical exertion. Indicators of heart rate variability (HRV) showed a statistically significant increase after the 5-kilometer run (p<0.01). Parametric pulse amplitude and normalization index also increased after running (p<0.01) indicating increased cardiovascular function. We found a decrease in the overall HRV at the median from 1313.5 to 1038.5 ms² after the forced march, however this change was not statistically significant (p=0.06). A decrease in HRV was observed in the low-frequency and high-frequency ranges. There was also an increase in the dominance of low-frequency HRV at the median from 0.63 to 0.78 (p=0.02) and a decrease in the high-frequency range at the median from 0.37 to 0.22 (p=0.02). The analysis of the sensorimotor functions showed an improvement in the accuracy of the sensorimotor reaction after running (p=0.02). The number of anticipations decreased significantly indicating a decrease in the number of false responses to a moving object (p=0.02). The number of delays increased (p=0.04) after physical exertion which may be related to fatigue. Conclusions. The results are important as they provided additional data on the functional state of the body after specific physical exertion. Monitoring HRV and sensorimotor functions can be a useful tool for assessing the body's recovery after physical exertion, determining optimal physical exertion, and identifying possible disruptions in the body's adaptive capabilities. [ABSTRACT FROM AUTHOR]

The unique diffraction geometry of ESRF beamline ID06-LVP offers continuous static 2D or azimuthally resolving data collections over all accessible solid angles available to the tooling geometry. The system is built around a rotating custom-built Pilatus3 CdTe 900k-W detector from Dectris, in a configuration equivalent to three butted 300k devices. As a non-standard geometry, here the method of alignment, correction and subsequent integration for any data collected over all solid angles accessible, or over any azimuthal range contained therein, are provided and illustrated by parameterizing and extending existing pyFAI routines. At 1° integrated intervals, and typical distances (2.0 m), the system covers an area of near 2.5 m2 (100 Mpx square equivalent), to 0.65 Å resolution, at 53 keV from a total dataset of some 312 Mpx. Standard FWHMs of SRM660a LaB6 vary from 0.005° to 0.01°, depending on beam size, energy and sample dimensions, and are sampled at an elevated rate. The azimuthal range per static frame ranges from <20° to ~1° over the full range of the detector surface. A full 2θ--intensity data collection at static azimuth takes 1-3 s typically, and can be reduced to ms-1 rates for measurements requiring time-rate determination. A full solid-angle collection can be completed in a minute. Sample detector distances are accessible from 1.6 m to 4.0 m. [ABSTRACT FROM AUTHOR]

This themed issue explores the different length scales and timescales that determine the physics and chemistry of a variety of key materials, explored from the perspective of a wide range of disciplines, including physics, chemistry, materials science, Earth science and biochemistry. The topics discussed include catalysis, chemistry under extreme conditions, energy materials, amorphous and liquid structure, hybrid organic materials and biological materials. The issue is in two parts, with the present part exploring glassy and amorphous systems and materials at high pressure. This article is part of the theme issue 'Exploring the length scales, timescales and chemistry of challenging materials (Part 1)'. [ABSTRACT FROM AUTHOR]

The results of karyological and cytogenetic studies of populations of conifer species from the families Pinaceae and Cupressaceae growing under extreme conditions have been summarized. A chromosomal variability has been revealed in coniferous plants growing at the southern and northern borders of their natural habitats, at ecological limits of distribution, in anthropogenically disturbed ecosystems, and under introduction conditions. A high frequency of changes in the number of chromosomes (mixoploidy, aneuploidy, and polyploidy) and their morphology has been observed. Different types of chromosomal anomalies (ring and polycentric chromosomes, chromosome fragments, and multiple chromosomal abnormalities), chromosome agglutination, mitotic and meiotic abnormalities, and the appearance of B chromosomes have been revealed. Using classical methods and fluorescent in situ hybridization (FISH), a polymorphism of nucleolar-forming regions of chromosomes has been studied and features of the 5S and 45S ribosomal DNA loci have been revealed. [ABSTRACT FROM AUTHOR]

The scientific work is aimed at finding ways to improve the components of the psychophysical readiness of police officers to use service firearms. In order to solve the research tasks, an analysis of the sources of international and domestic law regulating the use of force, special means, and firearms by the police has been carried out, including the UN Code of Conduct for Law Enforcement Officials, the Declaration on the Police, Basic Principles of the Use of Force and Firearms by Officials on maintaining law and order, the Constitution of Ukraine, the Criminal Code of Ukraine, the Law of Ukraine “On the National Police”, Regulations on the organization of official training of employees of the National Police of Ukraine, Instructions on safety measures when handling weapons, Regulations on the organization of initial professional training of police officers who are first accepted on police service. The algorithm for applying coercive police measures proposed by the UN hs been considered, that is communication – persuasion – physical force – special means – firearms. A comparative characterization of the indicators of firearm owners per 100,000 population abroad with a similar indicator in Ukraine has been carried out. The peculiarities of the legal regulation of the use of coercive police measures in Ukraine under martial law conditions have been determined. The legal, social, domestic and psychophysiological factors that affect the decision-making by police officers on the possibility of using a registered firearm have been given. Based on the conducted research, the study of special literature, and the analysis of the activities of practical police officers who have at least 5 years of service, it has been established that the components of psychophysical readiness for the use of service firearms are physical, psychological, fire (shooting) and tactical-special training. Ways of a complex combination of the specified areas of psychophysical readiness for the use of service firearms have been proposed.

SiC ceramics are attractive electromagnetic (EM) absorption materials for the application in harsh environment because of their low density, good dielectric tunable performance, and chemical stability. However, the performance of current SiC-based materials to absorb EM wave is generally unsatisfactory due to poor impedance matching. Herein, we report ultralight SiC/Si3N4 composite aerogels (~15 mg·cm−3) consisting of numerous interweaving SiC nanowires and Si3N4 nanoribbons. Aerogels were prepared via siloxane pyrolysis and chemical vapor reaction through the template method. The optimal aerogel exhibits excellent EM wave absorption properties with a strong reflection loss (RL, −48.6 dB) and a wide effective absorption band (EAB, 7.4 GHz) at a thickness of 2 mm, attributed to good impedance matching and multi attenuation mechanisms of waves within the unique network structure. In addition, the aerogel exhibits high thermal stability in air until 1000 ℃ and excellent thermal insulation performance (0.030 W·m−1·K−1). These superior performances make the SiC/Si3N4 composite aerogel promising to become a new generation of absorption material served under extreme conditions.

Modern view on extreme and terminal conditions with special emphasis on etiology, pathogenesis and approaches to treatment are described.

In order to evaluate the overall safety performance of jacket platform under extreme storm conditions, a finite element model of the platform was established based on ABAQUS finite element software. The static analysis of the platform was carried out under the extreme average wind condition, and the dynamic analysis of the platform was carried out under extreme fluctuating wind condition. The stress, displacement, velocity and acceleration responses of the platform under three extreme storm conditions were mainly discussed. The results show that the platform is prone to stress concentration at the connection between pile leg and pile foundation, the displacement and stress response of the platform under extreme storm conditions meet the design requirements, the natural frequency of the strong axis of the platform is greater than the weak axis of that, and the natural vibration period is much less than the wave period, so it will not resonate. Meanwhile, the extreme values of displacement, velocity and acceleration response of the platform under extreme storm conditions can provide a basis for the setting of early warning threshold of structural vibration monitoring system. [ABSTRACT FROM AUTHOR]