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In this work, we have analyzed Bianchi type-I space-time (spatially homogeneous and anisotropic), using an interacting two fluid - dark matter (DM) and Pilgrim dark energy (PDE) in the framework of f(T) gravity by taking into consideration the infrared (IR) cut-off as a candidate of Hubble’s horizon L=1/H. We have also performed the state-finder diagnostics and in addition, energy conditions are discussed to verify accelerating expansion of the universe.

A locally rotationally symmetric Bianchi-I model filled with strange quark matter (SQM) is explored in f(R, Lm) gravity as a non-linear functional of the form f(R, Lm)=R/2 +Lαm, where α is the free model parameter. We considered the special law of variation of Hubble’s parameter proposed by Berman (1983) and also used the power law relation between the scale factors to obtain the exact solution of the field equation, which matches the model of the universe. We also analyze the physical and geometrical aspects of the universe’s kinematic and dynamic behavior. Additionally, we employ equation-of-state (EoS) parameters and statefinder parameters as analytical tools to gain insights into the evolution of the universe. We use the ΛCDM model as a benchmark to validate the results. By placing the deviations of the universe from ΛCDM model and yet making important contributions to the study of the anisotropic nature of f(R, Lm) gravity within the framework of cosmological dynamics, the paper increases our comprehension of our cosmic evolution.

Of many extended theories of gravity, f(R, T) gravity has gained reasonable interest in recent times as it provides interesting results in cosmology. Logarithmic corrections in modified theories of gravity have been studied extensively. In this work, we considered logarithmic correction to the trace term T and took the functional form as f(R, T) = R+16πGαlnT where α is a free parameter. The free parameter is constrained using dark energy density parameter ΩΛ and Hubble parameter H0. The lower bound is found to be α ≥ −9.85×10−29. The cosmological implications are also studied.

In this paper, the investigation explores an anisotropic cosmological model based on Marder’s space-time Tsallis holographic dark energy (THDE) within the framework of f(R, T) theory of gravity, where R represents the Ricci scalar and T signifies the trace of the stress energy-momentum tensor. field equation have solved for class of f(R, T) gravity i.e. f(R, T) = R + f(T). To obtain the precise solution, we employed the density of the THDE model along with the volumetric expansion laws, namely the power law and exponential law. Also explores the physical and geometrical aspects of the model.

This research paper delves into a thorough examination of the behaviour exhibited by higher dimensional Bianchi Type-I universes, incorporating the presence of quark and strange quark matter within the framework of f(R,T) gravity. The solutions derived for the field equations encompass both exponential volumetric expansion and power law scenarios. Under the exponential expansion model, both the pressure (pq) and energy density (pq) associated with quark matter are initially finite at the inception of cosmic time, gradually diminishing to zero as time progresses towards infinity. Conversely, within the power law model, these parameters start off infinitely large at t = 0, subsequently decreasing to zero as time approaches infinity. Furthermore, an exploration of the physical and geometrical attributes of the model is conducted. Notably, in power law expansion models, the behaviour of strange quark matter mirrors that of quark matter concerning pressure (p) and energy density (ρ). But in exponential expansion model quark pressure and strange quark pressure behave differently. The bag constant emerges as a critical factor influencing the universe's expansion, with observations revealing that both pressure and energy density tend towards the bag constant at large time scales (t→∞). Specifically, the pressure p→ -BC and the energy density ρ→ BC as time approach infinity. The negative pressure sign denotes the universe's expansion during later epochs.

Background. The problem of precise and reliable evaluation of the emotional state of operators in spaceflight conditions still remains unresolved, and therefore relevant. This evaluation is especially important for predicting operators` professional activity effectiveness considering the current emotional state which significantly determines the accuracy and rapidity of professional tasks performance. Objectives. Our study is carried out to empirically test the new method and technology for evaluating changes in the emotional state of the 7-day experiment participants measuring facial expression changes in their DPC-video interview recordings. Study Participants. The study involved 10 men aged 25 to 35 years. Volunteers were selected by the Institute of Biomedical Problems of the Russian Academy of Sciences as participants in the research. Methods. DPC video interviews were conducted daily in the morning and in the evening. Facial expression changes evaluation was conducted with the EmoRadar software which detects FACS action units (AUs), seven basic emotions and other patterns of facial activity. Results. The description of facial expression changes in the experiment are given based on the data from two participants. These changes were compared with the emotional experience of the participants and experimental conditions. The necessity of differentiated evaluation of the positive emotion of happiness is shown since its assessments may include not only happiness as a basic emotion, but also two expressions of smiles (social smile or coy smile) similar to it. The effectiveness of the software used and the author's approach to computer analysis of facial activity is clearly shown. Conclusions. With the help of the developed technology based on the implementation of a comprehensive approach to measurement and interpretation of facial expressions, it is possible to provide objective information about characteristic changes in facial expressions as reliable behavioral indicators of a person's emotional state. The data are independent of respondents' self-assessments or expert’s experience. This opens up new methodological possibilities for aerospace psychology to solve the problem of automatic monitoring of the emotional state of operators.

We investigate the cosmological scenario involving spatially homogeneous and anisotropic Bianchi type-V I0 space-time in the context of the Sharma-Mittal holographic dark energy model within the framework of Brans-Dicke’s theory of gravitation. In order to achieve this objective, the Hubble, deceleration, equation-of-state parameters have been discussed. The deceleration parameter (q) is used to measure the pace at which the expansion of the universe is accelerating. The equation-of-state parameter (ωsmhde) characterizes the quintessence and vacuum areas of the universe. All the parameters demonstrate consistent behaviour following the Planck 2018 data. We assess the dynamical stability by defining the squared speed of sound and examining its behaviour. In addition, the energy conditions and the variation of ωsmhde and ω′smhde in the model indicate the present accelerating expansion of the universe.

The objective of the present study is to find the characteristics of evolution of a homogeneous and isotropic universe in the framework of Brans-Dicke (BD) theory of gravity. FLRW space-time, with zero spatial curvature, has been used to obtain BD field equations. Scale factor and Hubble parameter have been obtained from an ansatz for the deceleration parameter, assumed on the basis of its property of signature flip indicating a change of phase from deceleration to acceleration. Validation of the model has been achieved by a suitable parametrization of that ansatz. Expressions for energy density, pressure, equation of state (EoS) parameter, cosmological constant, gravitational constant have been derived and depicted graphically. The gravitational constant is found to decrease with time at a gradually decreasing rate. The Hubble parameter, deceleration parameter and energy density decrease with time, which is in agreement with many other studies. The value of the EoS parameter at the present epoch is negative, and it becomes more negative with time. The cosmological constant increases very rapidly in the early universe from negative to smaller negative values, becoming positive finally, with a much slower change thereafter. A cosmographic and a geometrical analysis have been carried out. It is observed that a gradual transition takes place from a regime of quintessence to phantom dark energy. An important finding of this study is that the signature flip of the deceleration parameter takes place almost simultaneously with the signature flip of the cosmological constant, implying a connection between accelerated expansion and dark energy, which is represented here by the cosmological constant. Unlike the common practice of using arbitrary units, proper SI units for all measurable quantities have been used. This theoretical investigation provides the reader with a simple method to formulate models in the framework of BD theory.

In this paper, we study spatially homogeneous and anisotropic Bianchi type-I space-time filled with perfect fluid within the framework of f(R,T) theory of gravity for the functional form f(R,T)=R+2f(T) with f(T)=αT+βT2, where α and β are constants. Exact solutions of the gravitational field equations are obtained by assuming the average scale factor to obey a hybrid expansion law and some cosmological parameters of the model are derived. Two special cases, leading to the power-law expansion and the exponential expansion, are also considered. We investigate the physical and geometrical properties of the models by studying the evolution graphs of some relevant cosmological parameters such as the Hubble parameter (H), the deceleration parameter ( q) etc.

In the present study, a homogeneous and anisotropic LRS Bianchi type-I universe model is considered with an interacting dark matter and Renyi holographic dark energy model (RHDE) in f(R) gravity. The deceleration parameter (DP) shows a signature flipping for a universe which was decelerating in past and accelerating at present epoch. Therefore, the DP is a most physically justified parameter to analyze the solution of cosmological model. In order to find an exact solution of the field equations of the model, the shear scalar is considered to be proportional to the expansion scalar. We have considered f(R) = b Rn, the depiction model of f(R) which is the function of Ricci scalar R. The physical and geometrical characteristics of the universe model have been studied.

In this paper, we analysed the five-dimensional plane-symmetric cosmological model containing perfect fluid in the context of f(R, T) gravity. Field equations have solved for two class of f(R, T) gravity i.e., f(R, T) = R + f(T) and f(R, T) = f1(R)f2(T) with the inclusion of cosmological constant Λ and quadratic equation of state parameters in the form p = αρ2 − ρ, where α is a constant and strictly α≠ 0. In order to derive the exact solutions, we utilize volumetric power law and exponential law of expansion. The physical and geometrical aspects of model have discussed.

In the context of current scenario, it is crucial to look beyond Einstein’s theory, which opens the door to certain modified theories of gravity. So, present study is devoted to investigate the various energy conditions, particularly, strong energy condition (SEC), weak energy condition (WEC), null energy condition (NEC) and dominant energy condition (DEC) corresponding to different functional forms of f(R) gravity. We have studied for flat, isotropic and homogeneous FLRW cosmological model filled with interacting field i.e., perfect fluid is coupled with mass less scalar field for different models of modified f(R) gravity in which R is the Ricci scalar. We have observed, the accelerated expansion of the Universe which exact match with recent observational evidences.

In this article, we examine the LRS Bianchi type-I cosmological model in the framework of f(R, T) gravity, where R is the Ricci scalar and T is the stress energy momentum tensor in the presence of Domain wall. we used the special law of variation of Hubble’s parameter proposed by Berman (1983) to obtained the exact solution of field equation, corresponds to the model of the universe. The Energy conditions and physical behaviour of the universe has been obtained and their evolution has been discussed using some physical parameter and by means of their graphs. Also, we can use the Statefinder parameter for testing the validity of the model.

Purpose. To determine a reasonable place for installing the equipment unit for the fire-rescue motorcycle, which allows maintaining the stability of the motorcycle when driving at a speed of v ≤ 70 km/h. Methods. To calculate the motorcycle motion model Matlab was used. Findings. The methods have been developed for determining the coordinates of the center of gravity of a multifunctional fire and rescue motorcycle equipped with an equipment unit. The effect of motorcycle speed on its stability when turning around was researched. Application field of research. The results of the work can be used in recommendations for motorcycles exploitation in case of moving to the fire place.

Article analyzes scientific achievements and heritage of Elena Grigor’evna Minina – famous Russian scientist, biologist, plant physiologist (24.04.1903 – 01.04.1989). Being an outstanding researcher in many fields of reproductive biology and plant physiology, E. G. Minina created the doctrine of sex determination and sexual reproduction in plants and the influence of phytohormones on the processes of sexualization. She considered the course of the processes of sexualization as a complex chain of chemical transformations, primarily the redox system and hormonal regulation. Elena Grigor’evna determined the directions of the studies under environmental stress, laid the foundations for studying the patterns of morphogenesis, sexual transformations in woody plants. She was the first to describe sexual transformations in the Siberian stone pine (Pinus sibirica Du Tour) trees with acceleration of the reproductive cycle. These forms show signs of apomixis, characteristic of thriving angiosperms. Much attention in Elena Grigor’evna’s research was paid to elucidating the role of gravity in the processes of growth, formation and seed-bearing in coniferous plants. The criterion of the initial stage of atmospheric pollution, in her opinion, may be the direction of growth of lateral shoots. She is particularly interested in the problems of evolutionary physiology and reproductive biology of plants, provides schemes of phylogenetic relationships in the evolutionary development of angiosperms and gymnosperms. The level of evolutionary advancement of taxa and individuals within the species, in her opinion, is manifested in the intensity of photosynthesis, carbohydrate-nitrogen metabolism, biosynthesis of gibberellins and growth processes. According to Elena Grigor’evna’s teaching, a biotechnology of somatic embryogenesis of coniferous species is being developed, in which somatic cells in in vitro culture switch to the path of embryonic development, forming numerous embryos and plants with selectively significant traits. The list of the main scientific publications and the list of dissertations defended under his supervision is given.

Available observational data regarding current cosmological characteristics suggest that the universe is, to a large extent, both isotropic and homogeneous on a large scale. In this study, our objective is to analyze the Friedmann-Lemaitre-Robertson-Walker (FLRW) space-time using a perfect fluid distribution. We specifically investigate the framework of f(R, Lm) gravity within certain constraints. To accomplish this, we concentrate on a specific nonlinear f(R, Lm) model, represented by f(R, Lm) = R/2 + Lαm. The field equations are solved using the equation of state parameter of the form of the Chevallier-Polarski-Linder (CPL) parameterization. The deceleration parameter study finds an accelerating universe at late times. The transition redshift is found to be ztr = 0.89 ± 0.25. Also, we discussed the physical and geometrical properties of the model.

In this paper, we aim to describe the cosmic late-time acceleration of the Universe in f(R,Lm) gravity framework proposed by Harko (2010) with the help of an equation of state for strange quark matter. To achieve this, we adopt a specific form of f(R,Lm) gravity as f(R,Lm) =R/2}+ Lnm, where n is arbitrary constants. Here we utilize a hybrid scale factor to resolve the modified field equations in the context of f(R,Lm) gravity for an isotropic and homogeneous Friedmann–Lemaître–Robertson–Walker (FLRW) metric in presence of strange quark matter (SQM). Also, we analyze the dynamics of energy density, pressure and the state finder parameters and explained the distinctions between our model and the current dark energy models in the presence of SQM. We observed a transition from an accelerating to a decelerating phase in the Universe, followed by a return to an accelerating phase at late times. Also, we analyzed the state finder diagnostic as well equation of state parameter and found that the model exhibited quintessence-like behavior. The conclusion drawn from our investigation was that the proposed f(R, Lm) cosmological model aligns well with recent observational studies and effectively describes the cosmic acceleration observed during late times.

In recent years, modified theories of gravity have been extensively studied because of the discovery and confirmation of the current phase of accelerated expansion of the universe. The f(R,T) theory of gravity is one such theory, proposed by Harko et al. in 2011, in which R is the Ricci scalar and T is the trace of the stress-energy tensor. In this paper, we study Bianchi type V universe in f(R,T) theory of gravity with time varying cosmological constant and a quadratic equation of state p=αρ2-ρ, where α≠0 is a constant. We obtain exact solutions of the field equations for two cases: one with a volumetric expansion law and the other with an exponential expansion law. The physical features of the two models are discussed by examining the behaviour of some important cosmological parameters such as the Hubble parameter, the deceleration parameter etc. We find that the models have initial singularity and the physical parameters diverge at the initial epoch. The model 1, corresponding to the volumetric expansion law does not resemble ΛCDM model while the model 2, corresponding to the exponential expansion law, resembles ΛCDM model. The energy conditions of the models are also examined and found to be consistent with recent cosmological observations.

Problem. The determination of the stages of stability for vehicles as technical systems when moving uphill on an inclined section of the road and their possible longitudinal roll back is considered. The considered stages ensure the safe operation of vehicles in various conditions and with various combinations of the values of the parameters that are included in the proposed equations characterizing the stability of the vehicle. Goal. The purpose of the paper is to improve the method of researching the physical foundations of the stability of vehicles when moving uphill on an inclined plane, the formation of mathematical models, which allows to significantly improve the mathematical support of the methods of calculating the stability of two-axle vehicles (cars, trucks, tractors, special and specialized vehicles, etc.) Methodology. The approaches adopted in the work to achieve the set goal are based on the classical laws of the mechanics of free-standing or moving objects, namely: the principle of possible movements, where calculated dynamic and mathematical models with their solutions are able to preserve the given conditions and parameters, and characterize the state of stability of the vehicle in case of its longitudinal roll back. Results. It was established and confirmed by a numerical examples that the longitudinal stability of a vehicle moving uphill depends on the longitudinal road slope, the vehicle design, the elasticity of the road surface, the critical overturning angle of the vehicle and its weight parameters. Originality. The proposed mathematical model of the longitudinal stability of the vehicle when moving uphill showed that its solution significantly depends on the values of the geometric parameters of the uphill and the vehicle, and also depends on the position of the center of gravity of the vehicle relative to the surface of the road surface. Practical value. The obtained equations for determining the values of the stability parameters of the vehicle when moving uphill on an inclined road section make it possible to specify the parameters for ensuring the logistics of vehicles in the conditions of their operation on uphill.

An algorithm and a program for transformation of gravity anomalies for large territories are presented. The spherical shape of Earth is taken into account and the geodetic coordinates of measuring points are used. The calculations use the «quasi-ellipsoidal» model of V.V. Kavraisky, which allows the transition from geodesic to spherical coordinate system with increased accuracy. The algorithm is based on a source-like approximation of the field values, located in the nodes of a regular network, with the depths of the equivalent sources, depending on the latitude. To determine the source masses, the system of linear algebraic equations is solved by the fastest gradient descent method with an accelerated step calculation. The results of transformation of the gravity field in the Bouguer reduction for the Kuril island arc, the adjacent water areas and parts of land, located within 40°–54° N, 142°–162° E are presented with a total area of about 2.4 million km2. A slight difference between the recalculation results of gravity anomalies into the upper half-space using the «spherical» and «quasi-ellipsoidal» models of the Earth was experimentally established.

The relevance of the research is caused by the necessity to acquire new knowledge about the enrichment of gold-bearing ores and the need to develop the resource base of the Russian Federation, namely involve subsoil use objects in economic circulation. The purpose of the study is to study the processing of low-sulfide gold-quartz ore using an integrated technology for the enrichment of mineral raw materials. Object: gold ore raw materials with an average gold grade of 11,88 g/t. The silver content is negligible – 2,43 g/t. The main ore minerals in the sample are pyrite and pyrrhotite. The average content of these minerals in the ore, according to mineralogical and X-ray diffraction analysis, was about 6 % (in total). The main rock-forming minerals of the original ore are: quartz – 60,1 %; quartz-chlorite-mica aggregates – 3,8 %; carbonates – 7,1 %. Methods. The research methodology was based on the theoretical foundations of mineral processing. The study of the material composition of the ore, and enrichment products, was carried out using chemical, assay, thermal, spectrometric methods, as well as atomic emission spectrometry and other methods. The study of washability was carried out by the methods of gravity and flotation enrichment, namely: GRG test, stage test of the Institute TOMS (Russia) (determination of the optimal size of ore grinding and the number of enrichment stages), modeling of gold extraction in the grinding cycle, determination of the optimal degree of grinding, study of the choice of flotation reagents, study of the kinetics of the process and the implementation of a complex of technological studies. Results. It was found that the gold recovery when performing the GRG test was 72,75 % with a total concentrate yield of 1,34 % and a content of Au 664,78 g/t. At the same time, the gold content in the tailings was 3,29 g/t. A stage test showed that for ore processing only by gravity technology, it is advisable to use a two-stage scheme. The first stage is in the grinding cycle with the ore size of 60–70 % and the second stage – with the final size of the discharge of the classification 90 % size of –0,071 mm. Centrifugal separation, as a free gold recovery operation in a grinding cycle, works efficiently. A concentrate with a gold content of 2426 g/t was obtained with an output of 0,31 % and an extraction of 63,74 %. The enrichment of the first stage tailings crushed to 90 % size of –0,071 mm at the KC-CVD concentrator (modeling) made it possible to extract gold into a total gravity concentrate (KC-MD+KC-CVD) of 87,25 % with a concentrate yield of 22,63 %. The gold content in the tailings was 1,97 g/t. The results of gravity and flotation concentration of the original ore indicate the feasibility of using a combined gravity-flotation technological scheme. In a closed experiment of the initial ore beneficiation according to the gravity-flotation scheme at a natural pH of the pulp (without adding acid), the following products were obtained: gravity concentrate with a gold content of 2426 g/t at a yield of 0,31 % and an extraction of 64,06 %; flotation concentrate (after the II cleaning) with a gold content of 122 g/t with a yield of 2,90 % and recovery of 33,01 %; the total gold recovery in the gravity-flotation concentrate was 94,07 % with a yield of 3,21 % and Au content of 345,87 g/t, the gold content in the flotation tailings was 0,72 g/t.

Aerodynamic design analysis was conducted for the stability of a lightweight solar aircraft weighing 3 kg and a wingspan of 3.2 m. Airfoil analysis was conducted on four selected airfoils. The following factors were considered: good aerodynamic characteristics, low Reynolds number, high lift, low drag, high lift-to-drag ratio, quiet moment coefficient, moderate thickness, and camber curvature. WE-3.55.93 airfoil was selected as best and used to design the wing, and NACA 0008 was used to develop the empennage. The fuselage was designed with two compartments 1.9 m long, and the second compartment is made of aluminium or carbon fibre to reduce weight. The first compartment was 0.95 m long and 0.4 m in diameter. The centre of gravity was determined for the importance of the various aircraft components to ensure aerodynamic stability and balance. The complete assembly was designed using XFLR5 v6 software.

purpose: to experimentally substantiate the improvement of the physical preparedness of breakdancers at the age of 13-15 years using the functional simulator «Alpha Gravity». Material & Methods: theoretical analysis and generalization of scientific and methodological literature, pedagogical observation, pedagogical testing, pedagogical experiment, methods of mathematical statistics. The study involved 22 breakdancers aged 13-15 years, from the reserve of the national team of Ukraine. Two groups were formed from the study participants: the control group (CG) - 11 athletes and the main group (MG) – 11 athletes, in the educational process of which the means of the functional simulator «Alpha Gravity» were included. results: a positive effect of the application of a set of exercises using the «Alpha Gravity» functional simulator in the training process of breakdancers aged 13-15 years was revealed. The greatest increase in indicators of physical fitness of the athletes of the main group was found in the tests: T1 «Bend forward from a sitting position, legs together (cm)»; Т2 «Push-ups» (number of times min-1)”; T5 «Holding the torso in the prone position, (s)»; T6 «Plank, (s)». In other tests, there is also a positive trend in the growth of indicators. conclusions: statistically significant positive changes in the level of physical preparedness of breakdancers at the age of 13-15 years of the main group (MG, n=11) were established under the influence of the developed training methodology using the means of the functional simulator "Alpha Gravity".

According to Whitehead, nature is disclosed to mind by an ensemble of events characterized by unobservable hidden intrinsic factors (e.g., mass, gravitation) and observable extrinsic factors (e.g., motion, density). Mass is not the substratum of dynamics. It implies spatial extension and temporal duration, which are both necessary conditions of observable natural phenomena. Therefore, an instant, deprived of duration, is immeasurable. Whitehead’s claims on mass, space, and time corroborate Verlinde’s alternative conception of quantum gravitation. Within the de Sitter space-time, this conception starts from the competition of the short distance degrees of freedom of the Ryn-Takanayagi tensor with long-distance thermalized excitations. This enables the creation of a baryonic mass and a decrease in de Sitter entropy. The memory effect of the original baryon creation leads to gravitation and the production of extensive thermodynamic entropy. However, the baryon production shrinks, and the dissipating space-time transforms into a space-timeless cold sink with an accompanying strong contracting memory effect. This is equivalent to the alternate motion of a giant Carnot engine, where the heat source and sink energy exchange produce the eternal periodic dynamics of the Universe. This suggests that the Universe did not start from Big Bang but oscillated eternally as a Big Bounce Universe.

The article presents the research materials and results on artificial gravity for humans in space. We analyse several important and interrelated aspects of the development and application of artificial gravity in manned spaceflights and providing permanent safe, dignified human life in outer space from an interdisciplinary perspective and in the context of theory and practice. The article introduces philosophical foundations of artificial gravity from the perspective of praxeology and space biospheres environment management to ensure human life, safety, and development in space. A brief description of the conceptual model of outer space applications of artificial gravity for humans is made. The definitions are given. The main methods of creation and influence and modes of artificial gravity application for humans in outer space are systematized. This article reviews the global evolution of ideas, technologies, and artificial gravity projects in the 19th-21th centuries; it presents periodization, general classification and important examples. The article studies advances, issues, limits and perspectives of the research and application of artificial gravity for space exploration. The key conclusions are formulated.

The authors revealed an effect of gravitational field variations for the principal lunar wave O1, which preceded nearby earthquakes, using for the first time the approach based on the method of calculating tidal parameters in a sliding window with various window width (from 30 to 120 days). Since the observed data were free from the oceanic load, this effect is assumed to be associated with a local restructuring of the density medium in the solid Earth. A seasonal cyclycity was revealed for the K1 wave. Such cyclycity was not taken into account when compiling a solid Earth model PREM (preliminary reference Earth model).

The article comprehensively reveals the concept of an autonomous space island constellation to be deployed in orbits in the solar system. This project will make the Earth a green and blue oasis without harmful production and give humanity a chance to survive in any cataclysm on Earth. The authors propose an original idea and calculations regarding the simulation of Earth’s magnetic field and the system of magnetic simulators of artificial gravity. The concepts of an electric power supply system, the ozone layer, greening, water exchange and waste disposal are proposed. The article suggests that the construction of a space island constellation should be an international project of public organizations and private companies.

In the current article there is observed a serious problem of the development of preeclampsia (PE) at a level of severity among women in Ukraine. It is disassembled in the description of the main theories of the development of PE: allergic, hormonal and renal. So that it can be instilled in some types of diseases and the theory of cortical-visceral ailments, which is leading on the pink modern data.The study of cephalic changes to the pathogenesis of PE made it possible to see and describe the peculiarities of the structure of the placenta’s vessels with this pathology with an eye on the development of endothelial dysfunction; hormone-stimulating activity in the mother - placenta - fetus system. Statistically, persons are indicated in a hematoencephalic institution, they are seen in the organisms of fetuses from mothers from the stage of severity. All the above specialties are seen as far as the degree of severity of the PE. It has been shown that in fetuses from mothers and PEs in the later ontogeny, there may be a breakdown of the implementation and the main stages in the development of cells, uterus and uterine tubes. Moreover, there is a trend towards the development of the pathology of the organs of the statutory system in case of women, women of all types of mothers from the moderate and severe stage, as well as a great number of changes in the development of PE at a given birth.

The dynamic analysis and motion control of a spinning tether system for an interplanetary mission to Mars is considered. The space system consists of two spacecraft connected by a tether with thrusts to control its movement. The movements of the tether system in the sphere of action of the Earth, on the interplanetary trajectory and in the sphere of action of Mars are consistently analyzed. In near-Earth orbit, the transfer of the system into rotation with the help of jet engines installed on the end spacecrafts is considered. The spin of the system is used to create artificial gravity during the interplanetary flight. The tether system spins in the plane perpendicular to the plane of the orbital motion of the center of mass of the system. To describe spatial motion of the system, a mathematical model is used, in which the tether is represented as a set of material points with viscoelastic unilateral mechanical connections. When calculating the movement of the system, an approach based on the method of spheres of action is used. Spacecrafts are considered as material points. The level of gravity and spin of tether system is controlled by thrusters. The structure of the controller for controlling the angular speed of rotation of the tether system is proposed. The simulation results are presented to confirm the effectiveness of the proposed control algorithm, which provides a given level of artificial gravity for th e interplanetary mission under consideration.

Copyright of German International Journal of Modern Science / Deutsche Internationale Zeitschrift für Zeitgenössische Wissenschaft is the property of Artmedia24 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.)

Copyright of German International Journal of Modern Science / Deutsche Internationale Zeitschrift für Zeitgenössische Wissenschaft is the property of Artmedia24 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.)

Since Einstein’s failure to define a Grand Unified Theory, physicists have pursued a comprehensive theory explaining nature, a Theory of Everything. But because General Relativity, Quantum Field Theory, and Cosmology have little in common, defining one theory is an imposing task, having eluded the best scientists for ninety years. So are we close to defining a Theory of Everything? This analysis, after defining requirements (which must include initial conditions), identifies four possible options for a Theory of Everything. Quotes from prominent physicists express divergent views on each alternative.The leading proposal for a Theory of Everything is String Theory, which has possible issues. It requires supersymmetry, has extra compacted dimensions, and is background-dependent. A second less comprehensive theory is Loop Quantum Gravity, which emphases background-independence based on discrete quantum space. Explaining how theories define relationships between spacetime, quantum space, quantum time, and quantum gravity, positions the role of background-independence in proposed theories. If supersymmetry and extra dimensions are discovered, String Theory or a modified String Theory integrated with Loop Quantum Gravity, may be the option. Or, possibly a radically new theory might be developed. Or, as the last option considers, the answer to the question — Does a Theory of Everything exist? — may be no; if so, nature will always be a mystery.

Kant’s ‘Newtonianism’ has been rightly highlighted by figures like Friedman. The follow-up debates led to a more adequate view on Kant’s natural philosophy and in particular his relation towards Newton. But the discussion that evolved did not point to the asynchronicity that takes place in Kant’s struggle with the central Newtonian concepts. Newtonian space and gravity, in revised form, are of central concern to Kant’s critical philosophy. But Kant adapted and re-evaluated these two concepts in an asynchronous way. While Kant tries to integrate a notion of gravity into his theory of matter in his very first published writing, he has at this stage no adequate notion of space. At this time, as in regard to space, he can neither be called a Newtonian nor a proper Leibnizian and misconceives the necessity of an independent space for the foundations of physics. This perspective changes under the influence of Euler at the end of the fifties of the eighteenth century and finally leads to his writing of 1768 and the adoption of transcendental idealism in 1770. In the following, I depict this asynchronicity by taking central pre-critical writings into account while discussing Kant’s concept of space and gravity. This sharpens the picture of Kant’s work and the different stages his philosophy of nature went through. Further, it helps to understand the influence of Euler on Kant’s development in natural philosophy and his critical philosophy in general, as Kant under the influence of Euler formed deeper-going reflections on Newton’s theory of space and these mark turning points of his development.

In this article, the Gauss-Bonnet model of gravity is investigated, the action of which includes the Gauss-Bonnet invariant, the Maxwell term FμνFμν and the scalar field. The model is considered in a flat, isotropic and homogeneous Friedman-Robertson-Walker universe in four dimensions at the late stages of the Universe evolution. The Minkowski metric is used. For the researched model, a system of equations of motion and a solution with a scale factor with a power and modified power dependence on time are found. To find a solution, the method of variation was used. Similar solutions are obtained using the Euler-Poisson equation and the method of lowering the order of the derivative, followed by the usage of the Euler-Lagrange equation. The values of φ(t), energy density and isotropic pressure are obtained, the graphs of which correspond to modern cosmological data. In the course of the research, it turned out that for a scale factor with a power-law dependence on time within the framework of the researched model, the parameter of the equation of state is equal to the value obtained when solving a model with a modified power-law scale factor. The deceleration parameter is negative, which confirms the realism of the proposed model within the framework of an accelerated expanding universe. When considering the energy conditions, it turned out that the conditions are fulfilled in both models, but the SEC is not fulfilled. A comparison of the values of the energy conditions of the two models is shown. [ABSTRACT FROM AUTHOR]

This paper deals with the measurement of spectral moments of Serbian fricatives. The four spectral moments: centre of gravity, spectral variance, skewness, and kurtosis were measured at the onset of the fricative, on the stable-state part and at the fricative offset. The results show that the highest values for the centre of gravity can be found in non-sibilants, except for the sound [v]. The measurements were taken in both Hertz and Bark scales, and the results show that the Bark scale serves better in distinguishing fricative types. The energy which is generated during the fricatives' production is not evenly allocated in the time-course of the fricative length. Voiced and voiceless fricatives differ in force of articulation within the fricative duration. The greatest factor effects were found to be the place of articulation and phonological voicing. The vowel that follows does not statistically influence the spectral moments’ values, except for the difference in fricative [x] which surfaces as an acoustically different segment before the vowels [i] and [u].

This research is aimed at production and investigation of the potentials of blending mango gum with cashew gum on its binding properties as a substitute for gum Arabic. The high demand for adhesives has led to the search for other alternatives to Arabic and cashew gum due to their high cost and non-availability. Thus, the need to investigate the potentials of mango gum as well as the possibility of replacing mango gum with cashew gum to be employed as an adhesive. The raw gum was extracted from the mango tree, dried, sorted, underwent size reduction of the gum exudates, sieved into different mesh sizes, dissolved in distilled water and centrifuged to remove impurities and other polysaccharides. The binding properties of the extracted mango gum was monitored in terms of physicochemical properties such as viscosity, pH and specific gravity of the gum using capillary viscometer, pH meter and density bottle respectively. The variation of the agitation speed between 250, 500 and 750 rpm, particle size of the raw MG between 75 µm, 212 µm and 300 µm and the replacement of MG with CG from 0-50% at interval of 10% respectively. The effect of agitation speed, particle size of the raw MG and the replacement of MG with CG were investigated in terms of the viscosity, pH and specific gravity of the gum and found that the best quality gum was obtained at particle size of 75 µm, pH of 4.7, agitation speed of 500 rpm and specific gravity of 1.06 respectively. Results indicated that the use of additives such as glycerine, starch and zinc oxide enhanced the binding properties of the gum and MG as well as gums blended with CG were found to fall within the limits to be considered to possess good binding properties. An increase in MG replacement with CG up to 50 %, resulted in a decrease in viscosity and specific gravity of the blended gum by 21.32 % and 3.77 % respectively while pH experienced an increase from 4.4-5.7 i.e. more alkaline in nature.

The paper discusses the research results on the influence of forest types on the wood specific gravity of Scots pine as an integral indicator of wood quality. For the study, pine stands were selected in the forest conditions of the Precarpathian region (Ukraine). In the forest type of wet pine broadleaves biotope, wood density at the moisture content of 8% varied in the range from 356 to 735 kg∙m-3 with an average value of 511 kg∙m-3 and exceeded the similar indicator in fresh pine broadleaves biotope by 11%. A linear relationship between the wood specific gravity and the number of annual tree rings in 1 cm was established, which was described by the equation of the first level. A multiple comparison of the obtained research results allowed to distinguish four groups of wood samples in relation to wood density and the number of growth rings in 1 cm. The average value of the wood density for the first group of samples with the number of annual rings less than 5 pcs.∙cm-1 is equal to 385 kg∙m-3, and for the fourth with the number of annual rings more than 16 pcs.∙cm-1 - 601 kg∙m-3. The last one was characterized by the largest range of changes of the wood density, which varied from 445 to 735 kg∙m-3. The obtained results are of practical importance for the selection of stemwood for its desired purpose.

Purpose. To evaluate the functional adaptation of the visual system in the conditions of experimental modes of artificial gravity created on a short-radius centrifuge.Materials and methods. The study involved 9 healthy volunteers (9 eyes) aged 31.2±6 years. Each test person has passed 3 rotations on the short-radius centrifuge. The current factor in the tests was the overloads in the direction of ≪head-pelvis≫. Rotations were carried out in three modes, further conditionally designated ≪Mode 1≫, ≪Mode 2≫, ≪Mode 3≫ (maximum value of overloads at feet level up to 2.0; 2.4 and 2.9 G, respectively). Before and after each rotation the subjects underwent refractometry, determined pupil diameter, intraocular pressure and hydrodynamic parameters of the eye, evaluated hemodynamics in the vessels of the eye, orbit and i nternal carotid artery.Results. Intraocular pressure after the rotation in the modes 1 and 2 did not change, in the mode 3 – decreased by 1.0 mmHg according to tonometry (p=0.024), according to tonography by 2.8 mmHg (p=0.007) which correlated with a decrease in the rate of intraocular fluid production by 0.67 mm3 (p=0.046). After rotation in the mode 1 the blood flow rate in the internal carotid artery and the ophthalmic artery did not change, in the mode 2 the final diastolic blood flow rate in the internal carotid artery decreased by 2.6 cm/s (p=0.011), in the ophthalmic artery did not change, in the mode 3 the blood flow rate in the internal carotid artery did not change, in the ophthalmic artery – increased by 9.5 cm/s (p=0.015).Conclusions. Changes hemo- and ophthalmo-hydrodynamics in healthy subjects are within normal limits, which suggest that the visual system has wide possibilities of functional adaptation to the conditions of experimental modes of artificial gravity.

The article presents the research results of the influence of structural changes of the xylem of silver fir on wood density which has been reflected in the grouping of the number of annual rings in 1 cm and in the differences in the volumetric swelling of wood. For the study, wood samples in the fir stands of Transcarpathia (Ukraine) at the altitude of 800 m asl were selected. Silver fir wood was classified into four groups according to the number of annual rings in 1 cm and to wood density. The first group is represented by juvenile wood with the number of annual rings less than 2 pcs.∙cm-1. The highest density of wood with a moisture content of 10% was typical for the wood group with annual rings more than 13 pcs.∙cm-1, where wood density varied from 500 to 582 kg∙m-3 with a mean value of 533 kg∙m-3. Mean values of wood swelling indicate a significant difference between juvenile wood and mature wood with the number of annual rings of more than 13 pcs.∙cm-1. There was also a difference for the radial swelling of wood in the lower and upper ranges of the 95% confidence interval for the mean value. The relationship between volumetric swelling and wood density was described by an equation with the power function.

The application of a conservative numerical method of fluxes is examined for studying the vortex structures in the massive, fast-turned compact astrophysical objects, which are in self-gravity conditions. The simulation is accomplished for the objects with different mass and rotational speed. The pictures of the vortex structure of objects are visualized. In the calculations the gas-dynamic model is used, in which gas is accepted perfected and nonviscous. Numerical procedure is based on the finite-difference approximation of the conservation laws of the additive characteristics of medium for the finite volume. The "upwind" approximations of the densities of distribution of mass, components of momentum and total energy are applied. For the simulation of the objects, which possess fast-spin motion, the control of conservation for the component of moment of momentun is carried out during calculation. Evolutionary calculation is carried out on the basis of the parallel algorithms, realized on the computer complex of cluster architecture. Algorithms are based on the standardized system of message transfer Message Passing Interface (MPI). The blocking procedures of exchange and non-blocking procedures of exchange with control of the completion of operation are used. The parallelization on the space in two or three directions is carried out depending on the size of integration area and parameters of computational grid. For each subarea the parallelization based on the physical factors is carried out also: the calculations of gas dynamics part and gravitational forces are realized on the different processors, that allows to raise the efficiency of algorithms. The real possibility of the direct calculation of gravitational forces by means of the summation of interaction between all finite volumes in the integration area is shown. For the finite volume methods this approach seems to more consecutive than the solution of Poissons equation for the gravitational potential. Numerical calculations were carried out on the computer complex of cluster architecture with the peak productivity 523 TFlops. In the calculations up to thousand processors was used.

Multiverses are predictions based on theories. Focusing on each theory’s assumptions is key to evaluating a proposed multiverse. Although accepted theories of particle physics and cosmology contain non-intuitive features, multiverse theories entertain a host of “strange” assumptions classified as metaphysical (outside objective experience, concerned with fundamental nature of reality, ideas that cannot be proven right or wrong) topics such as: infinity, duplicate yous, hypothetical fields, more than three space dimensions, Hilbert space, advanced civilizations, and reality established by mathematical relationships. It is easy to confuse multiverse proposals because many divergent models exist. This overview defines the characteristics of eleven popular multiverse proposals. The characteristics compared are: initial conditions, values of constants, laws of nature, number of space dimensions, number of universes, and fine tuning explanations. Future scientific experiments may validate selected assumptions; but until they do, proposals by philosophers may be as valid as theoretical scientific theories.

Accuracy in determination of coordinates for image having simple shapes is considered as one of important and significant parameters in metrological optoelectronic systems such as autocollimators, stellar sensors, Shack-Hartmann sensors, schemes for geometric calibration of digital cameras for aerial and space imagery, various tracking systems. The paper describes a mathematical model for a measuring stand based on a collimator which projects a test-object onto a photodetector of an optoelectronic device. The mathematical model takes into account characteristic noises for photodetectors: a shot noise of the desired signal (photon) and a shot noise of a dark signal, readout and spatial heterogeneity of CCD (charge-coupled device) matrix elements. In order to reduce noise effect it is proposed to apply the Wiener filter for smoothing an image and its unambiguous identification and also enter a threshold according to brightness level. The paper contains a comparison of two algorithms for determination of coordinates in accordance with energy gravity center and contour. Sobel, Pruitt, Roberts, Laplacian Gaussian, Canni detectors have been used for determination of the test-object contour. The essence of the algorithm for determination of coordinates lies in search for an image contour in the form of a circle with its subsequent approximation and determination of the image center. An error calculation has been made while determining coordinates of a gravity center for test-objects of various diameters: 5, 10, 20, 30, 40, 50 pixels of a photodetector and also signalto-noise ratio values: 200, 100, 70, 20, 10. Signal-to-noise ratio has been calculated as a difference between maximum image intensity of the test-object and the background which is divided by mean-square deviation of the background. The accuracy for determination of coordinates has been improved by 0.5-1 order in case when there was an increase in a signal-to-noise ratio. Accuracy improvement due to increase of a diameter in a test-object is typical for large signal-to-noise ratios: 70 or more. The conducted investigations have made it possible to establish that the algorithm for determination of coordinates of the energy gravity center is more accurate in comparison with contour methods and requires less computing power (for the MatLab software package), which is related to discreteness while determining a contour.

The paper analyzes the utopian science fiction novel Red Star by A. Bogdanov (1908). The study focuses on the description of a fictional interplanetary travel analyzed in the context of scientific knowledge in the field of theoretical physics and astrophysics in the beginning of the twentieth century, and compares it with modern scientific concepts. A comparison of Bogdanov's technological imagery with the existing technologies of space travel is also presented. The study considers such concepts as antigravity, the theory of matter and 'minus-matter', ideas related to radioactivity and the possibilities of its use, the characteristics of the fictional interplanetary spacecraft etheroneph, the idea of the parameters of an interplanetary flight, including a description of weightlessness and its effects on a human body, space flight trajectory, the importance of using computer technologies, presented in the novel. While certain concepts had obviously been borrowed from the already existing sci-fi narrative, other details in the Red Star can be regarded as a novelty and original solutions predicting the later technological advances. They reveal the breadth of Bogdanov's background, almost unique in science fiction writers of the beginning of the twentieth century. [ABSTRACT FROM AUTHOR]

Recently growing number of low quality wood in Ukraine, damaged by fungal sap color, stem rot leads to finding ways to use it. Today this wood is used mainly for the manufacture of wood-fuels facility in industrial and municipal energy. A possible way to use it is making insulation material from wood wool. The existing prototype of such material - fibrolite contains woody wool of healthy wood but during burning emits toxic chemicals. The construction of wooden wall panels, which include a frame of lumber and thermal insulation material of wood wool, made of low quality pine wood and binder. The binder used were inorganic (liquid glass) and organic-mineral (PVA) dispersion with the addition of flame retardant. Investigation of fire resistance, acoustic and thermal insulation of material from low quality pine wood have proved that it meets the regulatory requirements and can be used in building structures. To develop technological requirements for the manufacture of wall panels using low-quality pine wood, it is necessary to determine their density, sorption capacity and bio-stability. For this purpose, samples of thermal insulation material with different content of mass parts of wood wool and binder were made. The density of specimens of insulating material (145‒250 kg/m3), which is close to the popular hard thermal insulation materials, has been determined. Experimental studies of moisture absorption, sorption capacity and swelling values indicated that the effect of moisture on the properties of insulating material and its shape resistance are within the permissible values of regulatory documents for construction products. Wood treated with binders found to be used for the manufacture of insulation material has been found to have high biological resistance, which is more than 5-6 times the bio-resistance of untreated wood. [ABSTRACT FROM AUTHOR]

The article deals with overall sustainability of stiffening diaphragm of support structures in engi- neering construction in the context of structural elements collaboration as a system «high rise construc- tion- foundation (base)- ground base». Calculations were made in the program complex LIRA-CAD. It was found out that the general stability of the bearing systems, which are paired diaphragms of rigidity in the form of support structures of a large-span structure with a highly located center of gravity, depends on their location on the base plate.

To analyze the characteristics of population settlement of certain areas different methodological approaches and techniques are used, among which сentrographic method occupies a special place. Centrographic method allows to determine the center of population gravity, the degree of its concentration around the central points of the territory, to identify the space-time changes in their placement, to compare the centers of population areas (democenters) with the gravity centers of the other geographical phenomena, which are obtained by similar formulas. By сentrographic methods using the geographic coordinates and location of the geographical center of Volyn region and the center of gravity of all urban and rural population of the region according to Census of 1979, 1989, 2001 are specified. The dynamics and trajectory of weight shift in population over the investigated period are analyzed, the values of discentrіsitets in the distribution of centers of gravity of all are determined, the urban and the rural population regarding the geographical center of the region. The basic causes of demographic displacement centers are established. On the basis of calculation of standard deviation centers the degree of concentration of all urban and rural population around their centers is revealed, and also the decrease of regional system of population settlement. The causes of spatial asymmetry in the distribution of population in the region are set, including important activation of suburbanizational processes in Luts ktown agglomeration and around urban settlements of the area. The parameters of standard deviation and scattering ellipse are calculated taking into account the ellipticity of the region territory, show that urban population of the region has a higher degree of concentration around its center of gravity than the rural population, because of the small number of urban areas on the periphery of the region and in its border areas.

Increasing the duration of orbital space flights up to 6–12 months and planning interplanetary missions actualizes the need for a better understanding of the mechanisms of osteopenia caused by microgravity. Investigation of mesenchymal stem cells (MSCs) that support the tissue homeostasis under microgravity conditions allows a deeper insight into the processes underlying bone loss. The purpose of this study was to investigate the osteogenic potential of MSCs under prolonged simulated microgravity by clinorotation. Using the method of mineralized matrix detection, it has been found that MSCs osteogenic potential decreased after long-term clinorotation. The investigation of major osteogenic gene expression has showed decreased trans­criptional activity in RUNX2, ALPL-1, Col-1, but increased expression of PPARγ. One of the reasons for the decreased osteogenic potential of MSCs may be an increased level of reactive oxygen species (ROS) after 30 days of clinorotation. ROS may affect cellular signaling cascades, such as Wnt, Hedgehog and FOXO pathways, thereby leading to a shift of the differentiation potential to adipogenesis.

A possible extension of the Newton's law applicability is discussed. A dependence of the gravitational constant on body density is considered.

In the bronchial asthma structure the mild form of the disease takes the leading place: from 50 to 75% of patients suffer from mild asthma. Modern diagnostics of disease in these patients and adequate therapy allow preventing the disease progress. This article discusses issues of determination of the bronchial asthma gravity, incidence rate, disease burden and standard approaches to therapy of the mild bronchial asthma. Particular attention is given to a new possibility of therapy of mild asthma in adult patients with the help of the combined drug Salbutamol/Beclomethazone represented in the form of an aerosol inhaler and intended for arrest of symptoms and permanent therapy of bronchial asthma and chronic obstructive pulmonary disease in adults from the age of 18. Use of fixed combination Salbutamol/Beclomethazone in the regime “on demand” in adult patients with mild bronchial asthma leads to increase of the time to the first exacerbation and reduction of the disease exacerbations, at the same time it is accompanied by the minimum cumulative dosage of the inhalation corticosteroid and allows overcoming the low commitment of patients to therapy by inhalation corticosteroids.

Reexamining the assumptions underlying the General Theory of Relativity and calling an object's gravitational field its inertia, and acceleration simply resistance to that inertia, yields a simple field model where the potential (kinetic) energy of a particle at rest is its capacity to move itself when its inertial field becomes imbalanced. The model then attributes electromagnetic and strong forces to the effects of changes in basic particle shape. Following up on the model's assumption that the relative intensity of a particle's gravitational field is always inversely related to its perceived volume and assuming that all black holes spin, may create the possibility of a cosmic rebound where a final spinning black hole ends with a new Big Bang.