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Background and Objectives: The development and functioning of all living beings ends with the inevitable aging process, as a result of which the activity of all organs and the body as a whole is suppressed, which leads to imminent death. Protein glycation is considered to be one of the causes of aging. This process takes place throughout life, but it intensifies with age. Protein glycation is a reaction of covalent coupling of free amino groups of proteins and reducing carbohydrates, which proceeds without the participation of enzymes and leads to disruption of protein functions. This process is unregulated, as it occurs without the participation of biological catalysts. As a result of glycation of proteins in humans, inflammatory processes occur in the body and a number of diseases such as heart attack, stroke, atherosclerosis, cataract, glycemia, Alzheimer’s disease, diabetes mellitus, etc. develop. In the tasks of medical diagnostics, methods of monitoring the state of proteins in the human body are necessary. In this regard, the work is devoted to the study of the processes of interaction of human serum albumin globules (HSA) with globules of human glycated serum albumin (gHSA). Materials and Methods: In conducting a study of the spectral-kinetic characteristics of the eosin luminescent probe in solutions of glycated and non-glycated HSA, as well as in a mixture of glycated and non–glycated HSA, an exponential dependence of the second order was used to approximate the dependencies of DF (delayed fluorescence) and PHOS (phosphorescence), and an anisotropy equation was used to assume the formation of the gHSA-HSA complex. Results: It has been found that the intensity and kinetics of quenching of delayed fluorescence and phosphorescence of the eosin fluorescent probe associated with proteins are sensitive to the ratio of glycated and non-glycated proteins in solution. To explain the increase in the intensity and lifetime of eosin phosphorescence during the transition from a solution of HSA to a mixture of HSA and gHSA, it is assumed that the globules of HSA and gHSA form a complex of the composition of gHSA-HSA, as a result of diffusion encounters. The rotational mobility of this complex is much less than the separate globules of HSA and gHSA. The formation of the complex is confirmed by an increase in the anisotropy of delayed fluorescence and phosphorescence of eosin in a mixture of HSA and gHSA. Conclusion: The obtained results of the work can be used to diagnose the presence of a complex of glycated with non-glycated proteins in human blood plasma.

Freezing and thawing processes can change the structure of frozen soil and reduce the mechanical properties, thus affecting the stability of engineering infrastructures built in frozen soil. Due to the different settings of freeze-thaw cycles, a large number of experimental results cannot be effectively compared and analyzed. In addition, estimating the soil mechanical characteristics under freeze-thaw action has also become a research difficulty. In this paper, based on the frozen soil genetic creep theory, a spherical indenter is developed, and a freeze-thaw cycle–physical time analogy method is proposed. Using the number of cycles (numbers of freeze-thaw cycles) and the duration time (physical time–minutes), we can obtain the long-term strength curve family of the frozen soil and mapping the curve family into the same stress space to achieve the normalized strength curve, and thus we can predict the long-term deformation and shear strength. Finally, two soil samples are selected for testing, and the relevant equations for predicting the long-term shear strength are obtained. This method has important theoretical significance for the comparative study on the mechanical behavior of frozen soils under freeze-thaw actions. It also has value for engineering practice and stability analysis of infrastructures built in cold regions.

In 2019, the Institute of Permafrost of the Siberian Branch of the Russian Academy of Sciences and the Northwest Institute of Eco-Environment and Natural Resources of the Chinese Academy of Sciences concluded the agreements on joint research work. They decided to study the evolution of frozen soils at the base of roads and the territory adjacent to them, as well as to justify a set of measures to stabilize the permafrost situation. The works provide the study of the reaction of permafrost along the routes of railway lines in Russia and China. In Russia, the parties are examining in detail individual sections of the Far Eastern and Trans-Baikal railways. We present the results of surveys on one of these sections: a segment of the track dedicated to the Tynda station of the Far Eastern Railway. The object of research is very indicative from the point of the need to assess the dynamics of geocryological conditions in the strip of long-term operated linear structures. Here, the deformations of the roadbed have been manifested almost since the end of its construction (1974). Despite the implementation of several technical solutions in the form of cooling structures aimed at maintaining the soil temperature at the base of the structure in a frozen state, at present, the road is still subject to deformations. According to the current research results, it was revealed that the main reason for their occurrence is the flooding of the territory due to both natural and anthropogenic factors.

We consider a tubular membrane whose mechanical behavior is defined by a strain energy density function that combines the neo-Hookean model with the Demiray model. Both, the neo-Hookean and the Demiray models are isotropic material models, which found their application in the modeling of the mechanical behavior of biological soft tissue. This tubular membrane is subjected to an inner pressure, an axial stretch, and a change in the material volume due to swelling or deswelling. The interplay between the cylinder geometry and the loading conditions and different instability modes, namely, bulging bifurcation, bending bifurcation, and prismatic bifurcation, are studied. It is shown that a change in the material volume has a strong effect on the occurrence of these bifurcation modes because a change in the material volume may stabilize the cylinder against a particular bifurcation mode and may trigger another bifurcation mode at the same time. Despite the restriction to isotropic material behavior, this article shows that the material response to pressure, axial stretch, and material volume change is quite complex. [ABSTRACT FROM AUTHOR]

Permafrost, known for its high sensitivity to climate change and human activities, plays a crucial role in comprehending the environmental sustainability of Arctic cities. Yakutsk, being the largest city situated in continuous permafrost, has suffered irreversible damage to surface buildings due to the widespread permafrost thaw. Therefore, it is imperative to conduct detailed monitoring and assessment of surface deformation to ensure the stable operation of building facilities and to plan urban development situated above the permafrost. This study utilized 138 scenes of Sentinel‐1B images captured between 2017 and 2021 to process the surface deformation variations of Yakutsk using the Persistent Scatterer Interferometric Synthetic Aperture Radar (PS‐InSAR) method. The surface deformation rate map reflects that the study area is undergoing extensive surface subsidence. The cumulative deformation time series maps effectively trace the temporal and spatial evolution of surface deformation, with the highest surface subsidence rates exceeding 40 mm/year and maximum cumulative subsidence exceeding 250 mm. In‐depth analysis of the obtained results indicated that the permafrost in Yakutsk is undergoing degradation, and the primary reason for surface subsidence is the thawing of foundation soils and the degradation of ice‐bearing permafrost. This study provides basic data for the investigation of geohazards caused by surface subsidence in Yakutsk. [ABSTRACT FROM AUTHOR]

This research aimed to investigate the morphological changes of sandy soils with a varying number of freeze-thaw cycles (FTCs). The primary objective was to characterize the changes in particle morphology and establish the relationship between the number of FTCs and these changes. Two variables, namely the amount of variation and the coefficient of variation, were introduced as parameters to characterize the morphological changes of sandy soils. Statistical analysis was performed using the PIP9.1 particle dynamic image analyzer to quantify the morphological characteristics of sandy soil particles. The results showed that the five morphological characteristic parameters of sandy soil particles conformed to a normal distribution. The particle shape was primarily blocky, and sandy soil particles appeared more broken and regular in shape with an increase in the number of FTCs. The coefficients of variation of particle filling exhibit "conjugate" changes with other indicators, and the coefficients of variation of each indicator decrease gradually with an increase in the number of FTCs. Principal component analysis was employed to integrate information on sandy soil particle shape, resulting in a new index that established the relationship between the index and the number of FTCs. The findings of this study provide a better understanding of the morphological changes in sandy soils under freeze-thaw conditions and offer insight into the stability of sandy soils under these conditions. [ABSTRACT FROM AUTHOR]

Linear engineering facilities, such as gas transportation systems, extend from 30 to 500 metres in width and several hundred kilometres in length. Such routes pass through areas characterized by sufficiently diverse engineering, geological, geocryological and seismotectonic conditions. The safe and reliable functioning of gas transportation systems is ensured by their regular monitoring to prevent the development of hazardous exogenous geological processes. In particular, when monitoring ice formation, the greatest efficiency can be achieved by using unmanned aerial vehicles for low-altitude aerial surveys. In this research, remote sensing methods based on unmanned technologies were applied to assess the aufeis hazard in a section of the Power of Siberia gas pipeline in South Yakutia. The authors’ successful experience of using unmanned systems during an aeromagnetic exploration of iron ore deposits in South Yakutia was also considered. A series of studies, including georadar and electrical exploration profiling, as well as thermal imaging and high-resolution aerial photography by an aerial complex, was conducted to assess the dynamics of ice development over time in the area under study and to establish the signs of a developing hazardous process.

We demonstrate that strong elastic pump wave pulses soften sandstone more in humidified conditions than they do in dry conditions and that this effect is repeatable and reversible. We assess these changes via the non-linear interactions of a strong pump wave with a weaker probe wave. We find that there is an exponential time constant (τ ≈ 13 days) associated with this process that is independent of the amplitudes of the pump and the probe, the phase delay between the two waves (the time between transmission of the pump and probe waves), the sampling rate, and whether the sample is being dried or humidified. We demonstrate that the humidity-dependent differences in the amount of softening are induced by only a very small amount of absorbed water vapor and argue that this water is intercalated within clay particles. We also show that our pump–probe experiments detect these humidity-dependent differences in the amount of softening easily and repeatably using an experimental design that does not rely on resonance conditions. This means that, in principle, our experiments could be more easily generalized to other experimental geometries to investigate non-linear elastic properties in complex or irregular sample geometries. Our method and findings have potential relevance in oil and gas exploration, civil engineering, and understanding of the mechanism of earthquakes. [ABSTRACT FROM AUTHOR]

Residual stress may have an important influence on the mechanical response of residually stressed materials. This paper is concerned with the effects of residual stress on the stability of inflated, axially extended, residually stressed circular cylindrical tube. To this end, the theory of small incremental deformations superimposed on a large underlying finite deformation is used. Asymmetric and axisymmetric types of bifurcation are considered. It is found that for residual stress parameter γ of the same sign the effect of the residual stress is different depending on the type of bifurcation. For example, for asymmetric bifurcations with mode number m = 1 and with positive γ inclusion of residual stress makes the tube more stable, on the other hand, for axisymmetric bifurcations inclusion of residual stress, corresponding to positive residual stress parameter γ, leads to increase of instabilities. In all cases, residual stress with positive and negative residual stress parameter γ leads to a symmetric character of bifurcation curves. [ABSTRACT FROM AUTHOR]

This paper is devoted to the evaluation of the hardware resources of computer systems for solving a computationally expensive problem such as the calculation of the probability distributions of statistics by the second multiplicity method based on Δ -exact approximations of samples with a size of 320–1280 characters and an alphabet power of 128–256 characters. The accuracy is Δ = 10 − 5 and the total solution time should not exceed 30 days or 2.592 × 10 6 seconds for 24/7 computing. Owing to the use of the properties of the second multiplicity method, the computational complexity of the calculations can be brought within the range of 9.68 × 10 22 − 1.60 × 10 52 operations with the number of tested vectors at 6.50 × 10 23 − 1.39 × 10 50 . The solution of this problem for the specified parameters of samples during the given time requires hardware resources which cannot be provided by modern computer technology such as processors, graphics accelerators and programmable logic integrated circuits. Therefore, in this paper, we analyze the possibilities of promising quantum and photon technologies for solving the problem with the given parameters. The main advantage of quantum computer systems is the high speed of calculations for all possible parameter values. However, quantum acceleration will not be achieved to calculate the probability distributions of statistics due to the need to check all the obtained solutions. Here, the number of obtained solutions corresponds to the dimension of the problem. In addition, due to the current development level of quantum hardware components, it is impossible to create and use 120 qubit quantum computers for the solution of the considered problem. Photon computers can provide high computation speeds at low power consumptions and require the smallest number of nodes to solve the considered problem. However, unsolved problems with the physical implementation of efficient memory elements and the lack of available hardware components make the use of photon computer technologies impossible for calculating the probability distributions of statistics in the near future (5–7 years). Therefore, it is most reasonable to use hybrid computer systems containing nodes of different architectures. To solve the problem on various hardware platforms (general purpose processors, GPUs and FPGAs) and configurations of hybrid computer systems, we suggest to use the architecture-independent high-level programming language SET@L. The language combines the representation of calculations as sets and collections (based on the alternative set theory of P. Vopenka), the absolutely parallel form of the problem represented as an information graph and the paradigm of aspect-oriented programming. [ABSTRACT FROM AUTHOR]

As an important parameter in permafrost research, the annual ground surface freezing/thawing index is widely used in the variation of permafrost. In addition, it is also an important indicator in climatology, providing a large amount of theoretical basis for the assessment of climate change. Based on the ground surface temperature data recorded at 707 meteorological stations from 1960 to 2020, the ground surface freezing/thawing index in China were calculated. The results showed that over the past six decades, the thawing index has shown an upward trend, whereas the freezing index has shown a downward trend, and the trend is stronger around 2000. The results of the R/S-based analysis indicate that the freezing/thawing index will remain on a decreasing/increasing trend for some time to come. Based on the five warming scenarios published by Coupled Model Intercomparison Project Phase 6 (CMIP6), the spatial–temporal variation characteristics of the ground surface freezing/thawing index in China during 2020–2100 was simulated. It was found that under SSP3-7.0 and SSP5-8.5 scenarios, the freezing/thawing index may be 0 °C-days in 2080 and 2070, respectively, which may imply that the ground surface freezing process in some regions of China may disappear. [ABSTRACT FROM AUTHOR]

The conditions for bifurcation of a circular cylindrical tube of elastic material subjected to combined axial loading and internal pressure are well known and are frequently used as a reference in related works. The present paper takes the theory further by considering a residually stressed circular cylindrical dielectric tube subjected to a combination of internal or external pressure, axial load and radial electric field. We examine axisymmetric incremental deformations and increments in the electric displacement superimposed on a known finitely deformed and residually stressed configuration in the presence of an electric field. The governing equations and boundary conditions are first obtained in general form and then specialized for the neo-Hookean and Ogden electroelastic models. The system of equations is solved numerically for different values of charge density and radial and circumferential residual stresses, and the results are compared with the purely elastic case. The bifurcation curves are presented as the azimuthal stretch on the inner surface versus the axial stretch together with the corresponding zero pressure curves. This article is part of the theme issue 'The Ogden model of rubber mechanics: Fifty years of impact on nonlinear elasticity'. [ABSTRACT FROM AUTHOR]

Since the Quaternary, the alternate climate of dry and wet, cold and warm, and the emergence of glacial and interglacial periods have led to great changes in the global environment and climate. As an event closely related to cold climate, cryogenic soil has important reference significance for the study of climate change in a certain region and time period. The research on cryogenic soils mainly focuses on the following three aspects: particle size composition, surface morphology and mineral composition. Through the study of the relevant literature, we find that the correlation coefficient of particle size composition before and after freeze-thaw is used to determine the cause of cryogenic weathering. Due to the singleness of judgment conditions, the result is difficult to be convincing; It is difficult to prove the microscopic morphology of the cause of cryogenic weathering from a single mineral of quartz. Therefore, it is necessary to start with more types of primary minerals, and analyze the differences in the particle shape and microscopic surface morphology of different types of primary minerals during the cryogenic weathering process. And on this basis, the typical mineral morphology of the cause of cryogenic weathering is comprehensively judged; Freeze-thaw has little effect on the mineral composition of the soil, but has a greater impact on the size of the mineral particles, and this size change corresponds to the phenomenon of particles silt-fication. The mineral composition also controls the geochemical composition, and the insignificance of the mineral-chemical composition in the process of cryogenic silt-fication increases the difficulty of judging the cause of cryogenic weathering. [ABSTRACT FROM AUTHOR]

The cone-cylindrical pile foundation is a kind of shallow buried foundation, which needs to be open excavated and backfilled during construction. The density of the backfill is closely related to the refreezing process of the backfill. However, there is still a lack of relevant research on the relationship between backfill density and the refreezing process of backfill. The method of model experiment is selected to study the refreezing process of backfill under three backfill soil densities. The controlled density of backfill is 1.83, 1.62 and 1.36 g/cm3, and the times of freeze–thaw cycle is 14, 22 and 39, respectively. The main research findings are as follows: First, the effect of the initial temperature of the backfill on the refreezing is mainly reflected in the first three freeze–thaw cycles; the second is that the higher the density of the backfill, the faster the backfill responds to changes in outside air temperature, and the shorter the freezing time; third, the pile foundation is a good conductor of heat, which will cause the soil temperature change on the pile side to be significantly greater than that of the natural soil, and the temperature change of the pile foundation surface is greater than that of the backfill. The research results can provide a reference for the backfill construction of pile foundations in cold regions and the selection of boundary conditions for related numerical simulations. [ABSTRACT FROM AUTHOR]

Background: The bulk of relevant studies compare individual or very few sports and on small samples of athletes. This requires extensive analysing postural stability in various sports.Research Question: The main objective of our study was to identify the features of postural stability in a normal vertical stance in athletes of various kinds.Methods: This study compares postural stability in a normal bipedal stance with eyes open (EO) and eyes closed (EC) conditions among athletes (n = 936, age: 6-47 years) from different sports and performance level. Postural stability was measured through the center of pressure (COP) sway area (AS) and velocity (VCP) while standing quietly in a normal bipedal position with EO and EC on a stabiloplatform (50 Hz).Results: The order of VCP-EO increase in athletes compared to Control was as follows: Shooting (-11.3 %, p < .0001) < Football (-10.4 %, p < .0001) < Boxing (-8.7 %, p < .0001) < Cross-Country Skiing (-7.2 %, p < .0001) < Gymnastics (-7.0 %, p < .0001) < Running (-6.9 %, p < .0001) < Team Games Played with Hands (-6.8 %, p < .0001) < Wrestling (-6.3 %, p < .0001) < Tennis (-5.5 %, p = .0004) < Alpine Skiing (-5.4 %, p = .002) < Rowing (-5.0 %, p = .194) < Speed Skating (-4.7 %, p = .004) < Figure Skating (-3.6 %, p = .034) < Control.Significance: Practicing any kind of sport was associated with increased postural stability in normal bipedal stance. This is the first study that provides reference values of COP sway and velocity with and without visual control on a stable force platform for different sport groups. [ABSTRACT FROM AUTHOR]

The article is devoted to the study of cognitive mental states and personality properties relationship during educational activities. In practical terms, the most important task in the field of educational psychology is to develop methods for updating and regulation of cognitive states. The study of cognitive states carried out in various forms of educational activity: in an ordinary situation (a lecture) and in a tense situation of training (an exam). N = 90, 1-st year students at the Kazan Federal University. During the research used different questionnaires to diagnose the personality traits and the intensity of students' cognitive states, such as interest, reflection, concentration, mental stress etc. The data analysis included frequency analysis, the polar group method and the MANOVA method. Revealed that in an everyday situation of educational activity (lecture) the most often experienced states are thoughtfulness, interest and concentration, while in a tense situation of an exam - mental stress, doubt and concentration. In everyday situations, a state of thoughtfulness is observed in individuals with high Conscientiousness, and prevails in friendly, open-minded and emotionally stable students with a focus on the task. During the exam students with high activity, extraversion, and focus on the task experience the state of mental stress. Results of this research will find application in educational systems increasing the effectiveness of educational, scientific and creative activities, through the updating of students' positive cognitive states. Cognitive states stimulate and regulate cognitive activity, performing the function of development of cognitive processes and intellectual abilities. The influence of personality properties on cognitive states is mediated by both the intensity of educational activity and the interaction of the personality traits. [ABSTRACT FROM AUTHOR]

This paper considers the application of the triple Langmuir probe method to investigate the local plasma parameters of the radio frequency (RF) discharge that is placed in the applied magnetostatic field. The main criteria applicability for such a method for experimental diagnostics of RF plasma parameters is presented. As an example, this paper presents experimental results that were obtained using the proposed method on local plasma parameters in one of the cross sections of the discharge chamber of the RF ion source with an applied magnetostatic field. The influence of the magnetostatic field on the radial distributions of charged particle density and electron temperature is shown. [ABSTRACT FROM AUTHOR]

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Background: Human heredity is known to determine about 50% of heart rate variability (HRV) based on a twin study; however, genetic polymorphisms causing increased HRV in athletes are not known. Objectives: This article is aimed at studying the associations of uncoupling protein 2 (UCP2) Ala55Val (rs660339) and UCP3-55C/T (rs1800849) polymorphisms with heart rate variability (HRV) in trained oarsmen. Methods: HRVindices (standard deviations of NNintervals (SDNN), rootmeansquare of successive differences (RMSSD), HF, LF, VLF), stroke index and cardiac index of the young oarsmen (age 17.6 ± 1.6 years old, n = 23) were determined by impedance cardiography method in the supine and standing positions. Themaximumoxygen consumption (VO2max) was examined with a rower ergometer by means of a gas analyzer. Polymorphisms of the UCP2 Ala55Val and the UCP3-55T/C were genotyped by polymerase chain reaction (PCR) method and length analysis of restriction products. Results: It was found that both polymorphisms were not associated with VO2max. The UCP2 Val/Val genotype compared to the combined variant (Ala/Ala + Ala/Val) containing the 55 Ala allele, as well as the UCP3 T/T genotype compared to the combined variant (C/T + C/C) containing the -55C allele were associated with low HR and increased HRV: SDNN, RMSSD and HF vagal indices in the supine position. Moreover, the athletes with the UCP3-55T/T genotype had a pronounced increase in heart rate (ANOVA, P < 0.001) and a decrease in stroke index (ANOVA, P = 0.005) in response to active orthostasis compared to C/T and C/C genotypes. Conclusions: The UCP2 Val/Val and the UCP3 T/T genotypes may be genetic markers of increased HRV in the highly trained athletes, suggesting an influence of these UCP2/UCP3 polymorphisms on autonomic cardiovascular regulation. [ABSTRACT FROM AUTHOR]

To study Korteweg-de Vries (KdV) equation, whose solution is based on the evolution of the Sturm-Liouville (SL) operator, we have recently developed scattering theory of the SL operator for an arbitrary analytic potential on the line. Here, we create a basis for solutions of the KdV of a different class, considering continuously differentiable potentials using the Gelfand-Levitan theory on the half line. The solution of the spectral problem for this operator is achieved by constructing a special object, invented by Livšic in the late 1970s, and called vessel. The central object of a vessel is a compact perturbation of a self-adjoint operator for whichwedevelop a canonical form. Evolving the constructed vessel, we solve the KdV equation on the half line, coinciding with the given potential for t = 0. It is also shown that the initial value on the t-axis, or equivalently for x = 0, is prescribed by the choice of the spectral parameters, but can be perturbed using an "orthogonal" to the problem measure. The results, presented in this work, are following: (1) We address the KdV equation with initial values, satisfying Gelfand-Levitan theory assumptions, providing a detailed formula of the initial conditions for the x = 0, (2) we show that Nonlinear Shrodinger, canonical systems, and many more equations can be solved using theory of vessels, analogously to the Zacharov-Shabbath scheme, (3) we present a generalized inverse scattering theory on a line for potentials with singularities using prevessels, and (4) we present the tau function and its role in the solution of the problem. [ABSTRACT FROM AUTHOR]