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The study investigates alterations in the mechanical and thermophysical properties of ceramics composed of xLi2ZrO3–(1−x)Li4SiO4 as radiation damage accumulates, mainly linked to helium agglomeration in the surface layer. This research is motivated by the potential to develop lithium-containing ceramics characterized by exceptional strength properties and a resistance to the accumulation of radiation damage and ensuing deformation distortions in the near-surface layer. The study of the radiation damage accumulation processes in the near-surface layer was conducted through intense irradiation of ceramics using He2+ ions at a temperature of 700 °C, simulating conditions closely resembling operation conditions. Following this, a correlation between the accumulation of structural modifications (value of atomic displacements) and variations in strength and thermophysical characteristics was established. During the research, it was observed that two-component ceramics exhibit significantly greater resistance to external influences and damage accumulation related to radiation exposure compared to their single-component counterparts. Furthermore, the composition that provides the highest resistance to softening in two-component ceramics is an equal ratio of the components of 0.5Li2ZrO3–0.5Li4SiO4 ceramics.

Aim: The ability of synthetic 1,4-naphthoquinones (1,4-NQs) to prevent adenosine triphosphate (ATP)-induced and purinergic P2X7 receptor (P2X7R) mediated inflammation in macrophage and neurodegeneration of neuronal cells in vitro was previously established. The aim of the present study was to investigate analgesic-like and anti-inflammatory activity of 1,4-NQs thioglucoside derivatives, compounds U-286 and U-548, in in vivo experiments. Methods: Spectrofluorimetry approach and YO-PRO-1 fluorescent dye uptake determination were applied to study the effect of 1,4-NQs upon ATP-induced P2X7R mediated macropore formation in mouse neuroblastoma Neuro-2a cells and macrophages RAW 264.7 cells. An acetic acid-induced writhing test, hot plate test, and carrageenan-induced paw edema test were used as an in vivo mouse models to study the ability of 1,4-NQs to inhibit pain and inflammation. In the in vivo experiments, compounds were administered to mice intraperitoneally at dosages of 0.1 mg/kg, 1.0 mg/kg and 10.0 mg/kg. A group of animals that received injections of sterile water was used as a control. Each dosage group and the control group consisted of 6 mice. Results: In the present work the analgesic-like and anti-inflammatory activity of 1,4-NQs, U-286 and U-548, was demonstrated. Compound U-548 showed a significant inhibitory effect in antinociceptive tests reducing the number of mouse writhings and eliminating the latent time of mouse hind paw licking, correspondingly. Selected compounds were able to almost completely reduce the size of carrageenan-induced paw edema 24 h after injection and had a potent anti-inflammatory activity. Observed effects were accompanied with aptitude of studied 1,4-NQs to inhibit the formation of purinergic P2X7R macropore associated with inflammation and nociceptive pain. Conclusions: The results obtained allow to consider compounds U-286 and U-548 and as a pharmacological basis for the development of new analgesic-like and anti-inflammatory drugs.

The paper presents the results of studies of the resistance of lithium ceramics to helium swelling during its accumulation in the structure of the near-surface layer, and the identification of the three types of lithium ceramics most resistant to radiation degradation: Li4SiO4, Li2TiO3, and Li2ZrO3. The simulation of helium swelling under high-dose irradiation was carried out by irradiation with He2+ ions with fluences of 1 × 1016 ion/cm2–5 × 1017 ion/cm2, which allows for simulating the implanted helium accumulation with a high concentration in the damaged surface layer (about 500 nm thick). The samples were irradiated at a temperature of 1000 K, the choice of which was determined by the possibility of simulating radiation damage as close as possible to real operating conditions. Such accumulation can result in the formation of gas-filled bubbles. Through the application of X-ray phase analysis, indentation testing, and thermophysical parameter assessments, it was ascertained that among the three ceramic types, Li4SiO4 ceramics exhibit the highest resistance to helium-induced swelling. These ceramics experienced less significant alterations in their properties compared to the other two types. An analysis of the correlation between the structural and strength parameters of lithium-containing ceramics revealed that the most significant changes occur when the volumetric swelling of the crystal lattice becomes the dominant factor in structural alterations. This phenomenon is manifested as an accelerated degradation of strength characteristics, exceeding 10%. At the same time, analysis of these alterations in the stability of thermophysical parameters to the accumulation of structural distortions revealed that, regardless of the type of ceramics, the degradation of thermophysical properties is most pronounced under high-dose irradiation (above 1017 ion/cm2).

Biodegradable polymers, specifically polylactide, are an important part of food packaging and medical devices. Microbiological synthesis uses cheap renewable raw materials and industrial waste to produce a high yield of lactic acid, the monomer of polylactide. This method needs new effective lactic acid producing strains, e.g., thermophilic bacteria. The research involved thermophilic bacterial strains isolated from soil and compost samples. Their ability to produce organic acids and extracellular enzymes was tested using the method of high-performance liquid chromatography (HPLC) and microbiological tests respectively. The real-time polymerase chain reaction method (PCR) detected L-lactate dehydrogenase structural genes of L-lactate dehydrogenase of Bacillaceae. Strain T7.1 was fermented using glucose and yeast extract as carbon and nitrogen sources, respectively. The optical purity of lactic acid was evaluated using quantitative gas chromatography on a chiral column to separate lactate isomers. The molecular genetic analysis of the 16S rRNA gene sequence was applied to identify strain T7.1. The chromatographic analysis proved that 10 out of 13 isolated thermophilic strains were effective lactic acid producers. They demonstrated proteolytic, amylolytic, or cellulase activities. During the fermentation, strain T7.1 produced 81 g/L of lactic acid with a peak productivity at 1.58 g/(L·h). The optical purity of the product exceeded 99.9% L-lactate. The genetic analysis identified strain T7.1 as Weizmannia coagulans (Bacillus coagulans). The research revealed a promising thermophilic producer of optically pure L-lactic acid. Further research is needed to optimize the cultivation conditions, design an effective and cheap nutrient medium, and develop engineering and technological solutions to increase the yield.

Interest in composite ceramics based on oxide and nitride compounds is due to the combination of their structural, strength and thermophysical parameters. Moreover, in the case of composites based on xSi3N4 – (1-x)ZrO2, the strength parameters, as well as resistance to thermal expansion, are determined by the characteristics of zirconium dioxide, while the thermophysical parameters are determined by silicon nitride, for which the thermal conductivity values are almost an order of magnitude higher than for zirconium dioxide. The main method for production of composite xSi3N4 – (1-x)ZrO2 ceramics was the mechanochemical solid-phase synthesis method using high-speed grinding and thermal annealing, used to stabilize structural deformations caused by mechanical action. During the research, it was determined that a change in the ratio of ceramic components due to an increase in the contribution of Si3N4 in the composition leads to an increase in thermophysical parameters, the change of which is due to the higher thermal conductivity of silicon nitride. In turn, a change in thermophysical parameters, and as a consequence, an alteration in the rate of heat transfer due to phonon mechanisms, causes an elevation in resistance to external influences during thermal shocks. Experiments to determine resistance to thermal influences have shown that the presence of a high density of dislocations in the near-surface layer of ceramics contributes to a rise in resistance to temperature changes, alongside external mechanical influences, which is expressed in less pronounced trends in decreasing hardness indicators during heat resistance tests.

The study examines the influence of variations in the compositions of components for the production of lithium-containing ceramics based on lithium metazirconate obtained by the method of mechanochemical grinding and subsequent thermal sintering. For component variation, two compositions were used, consisting of zirconium dioxide (ZrO2) and two distinct types of lithium-containing materials: lithium perchlorate (LiClO4·3H2O) and lithium carbonate (Li2CO3). Adjusting the concentration of these components allowed for the production of two-phase ceramics with varying levels of impurity phases. Using X-ray phase analysis methods, it was determined that the use of LiClO4·3H2O results in the formation of a monoclinic phase, Li2ZrO3, with impurity inclusions in the orthorhombic phase, LiO2. On the other hand, when Li2CO3 is used, the resulting ceramics comprise a mixture of two phases, Li2ZrO3 and Li6Zr2O7. During the studies, it was established that the formation of impurity inclusions in the composition of ceramics leads to an increase in the stability of strength properties with varying mechanical test conditions, as well as stabilization of thermophysical parameters and a decrease in thermal expansion during long-term high-temperature tests. It has been established that in the case of two-phase ceramics Li2ZrO3/Li6Zr2O7 in which the dominance of the Li6Zr2O7 phase is observed during high-temperature mechanical tests, a more pronounced decrease in resistance to cracking is observed, due to thermal expansion of the crystal lattice.

This work examines the effects of the formation of impurity inclusions in the structure of NiAl2O4 ceramics when aluminum nitride is added to them and the occurrence of a reinforcement effect that prevents hydrogenation processes and the subsequent destruction of conductive and thermophysical characteristics. The appeal of ceramics possessing a spinel crystal structure lies in their potential use as ceramic fuel cells for both hydrogen generation and storage. Simultaneously, addressing the challenges related to ceramic degradation during hydrogenation, a critical aspect of hydrogen production, can enhance the efficiency of these ceramics while lowering electricity production costs. The selection of aluminum nitride as an additive for ceramic modification is based on its remarkable resistance to structural damage accumulation, its potential to enhance resistance to high-temperature degradation, and its ability to bolster strength properties. Moreover, an examination of the alterations in the strength characteristics of the examined samples subjected to hydrogenation reveals that the stability of two-phase ceramics is enhanced by more than three to five times compared to the initial ceramics (those without the addition of AlN). Additionally, it was noted that the most significant alterations in both structure and strength become apparent at irradiation fluences exceeding 1014 proton/cm2, where atomic displacements in the damaged ceramic layer reach over 5 dpa. During the evaluation of thermophysical properties, it was discerned that ceramics featuring an impurity phase in their composition exhibit the highest stability. These ceramics demonstrated a reduction in the thermal conductivity coefficient of less than 1% at the peak irradiation fluence.

The aim of this study is to determine the effect of changes in the phase composition of Al2O3–Si3N4 ceramics that were obtained using the method of mechanochemical solid-phase grinding on their resistance to the process of long-term thermal exposure, accompanied by the processes of oxidation and softening. The relevance of this research consists of determining the influence of the phase composition of ceramics on the change in their strength and thermophysical parameters, on the basis of which, we can draw a conclusion about the optimal composition of composite ceramics that have great prospects in the field of fire-resistant, heat-resistant, or radiation-resistant structural materials. During this study, the dynamics of the changes in the phase transformations of the xAl2O3–(1−x)Si3N4 ceramics, with variations in the ratio of the components, initiated by the thermal annealing of the samples, was established. According to the assessment of the phase transformations with variations in the ratio of the components, it was found that thermal annealing in an air environment at an Al2O3 concentration in the order of 0.3–0.5 M leads to the formation of an orthorhombic Al2(SiO4)O phase and an elevation in its contribution at concentrations above 0.5 M, which causes a rise in the thermophysical parameters and resistance to high-temperature degradation. During the heat resistance tests, it was found that the formation of the composite ceramics with the Si3N4(SiO2)/Al2(SiO4)O/Al2O3 phase composition results in an increase in the stability of their strength properties when exposed to thermally induced oxidation, which has a negative impact on their resistance to softening and a decrease in hardness. Moreover, the presence of the Al2(SiO4)O phase in the composition of the ceramics causes a slowdown in the processes of thermal oxidation of the Si3N4 phase under prolonged temperature exposure, alongside an increase in the degradation resistance of strength properties by more than 4–7 times, in comparison with the softening data established for single-component ceramics.

To protect the antenna systems of modern aircraft, radio-transparent dielectric fairings are widely used. At low flight speeds, when designing and evaluating the characteristics of the fairing-antenna, it is assumed that the dielectric constant is a constant value and does not depend on the aircraft's flight speed. As the flight speed increases, as a result of aerodynamic heating of the fairing, its dielectric permeability changes, which leads to errors in the processing of received signals. Currently, to take into account the effect of dielectric coatings heating when designing antenna systems, the temperature of the fairing wall is averaged over its thickness. This method during maneuvering and at high flight speeds leads to large errors in determining the characteristics of the fairing antenna since the nature of the temperature distribution along the thickness of the fairing wall is not taken into account. A new approach to the analysis of dielectric layers with their uneven heating along the thickness is proposed. The obtained results make it possible to adjust the signal processing algorithms with analog and digital matrices, as a result of taking into account the emerging heat flows affecting the fairing of the aviation antenna, which leads to the improvement of the characteristics of the antenna systems.

This paper presents the results of the influence of variation of the synthesis conditions of CuBi/CuBi2O4 films with a change in the applied potential difference, as well as a change in electrolyte solutions (in the case of adding cobalt or nickel sulfates to the electrolyte solution) on changes in the phase composition, structural parameters and strength characteristics of films obtained using the electrochemical deposition method. During the experiments, it was found that, in the case of the addition of cobalt or nickel to the electrolyte solutions, the formation of films with a spinel-type tetragonal CuBi2O4 phase is observed. In this case, a growth in the applied potential difference leads to the substitution of copper with cobalt (nickel), which in turn leads to an increase in the structural ordering degree. It should be noted that, during the formation of CuBi/CuBi2O4 films from solution–electrolyte №1, the formation of the CuBi2O4 phase is observed only with an applied potential difference of 4.0 V, while the addition of cobalt or nickel sulfates to the electrolyte solution results in the formation of the tetragonal CuBi2O4 phase over the entire range of the applied potential difference (from 2.0 to 4.0 V). Studies have been carried out on the strength and tribological characteristics of synthesized films depending on the conditions of their production. It has been established that the addition of cobalt or nickel sulfates to electrolyte solutions leads to an increase in the strength of the resulting films from 20 to 80%, depending on the production conditions (with variations in the applied potential difference). During the studies, it was established that substitution of copper with cobalt or nickel in the composition of CuBi2O4 films results in a rise in the shielding efficiency of low-energy gamma radiation by 3.0–4.0 times in comparison with copper films, and 1.5–2.0 times for high-energy gamma rays, in which case the decrease in efficiency is due to differences in the mechanisms of interaction of gamma quanta, as well as the occurrence of secondary radiation as a result of the formation of electron–positron pairs and the Compton effect.

Despite an extensive body of research the issues of teachers' continuous professional development are of particular importance for modern pedagogical theory and practice. The article outlines the features of public school teachers' professional development in Australia. The study employed a range of theoretical and applied research methods, namely comparative and historical, induction and deduction, logical, analytical, descriptive and statistical as well as questionnaires and interviews. The article specifies the functions of teacher professional development, its elements and components. It analyses the legislative basis and the genesis of Australian teachers' professional development standards. The article identifies the specificities of teacher professional development implementation in Australia. The results show that teacher professional development is a continuous process of deepening knowledge, improving skills and competencies, forming values and attitudes. The methods helped in revealing the interconnection between continuous professional development and educational reforms, the forms, models and methods of CPD of Australian and Ukrainian teachers. The results of the survey showed the potential for the system of Ukrainian continuous teacher education development and the possibilities of Australian experience adaptation taking into account our rich educational traditions.

The aim of this work is to study the mechanisms of polymorphic transformations in ZrO2 ceramics doped with MgO with different concentrations during thermal isochronous annealing, as well as the effect of the phase composition of ceramics on the change in strength properties and resistance to mechanical stress. Solving the problem of polymorphic transformations in zirconium dioxide by doping them with MgO will increase the resistance of ceramics to external influences, as well as increase the mechanical strength of ceramics. According to the data of X-ray phase analysis, it was found that the addition of the MgO dopant to the composition of ceramics at the chosen thermal annealing temperature leads to the initialization of polymorphic transformation processes, while changing the dopant concentration leads to significant differences in the types of polymorphic transformations. In the case of an undoped ZrO2 ceramic sample, thermal annealing at a temperature of 1500 °C leads to structural ordering due to the partial removal of deformation distortions of the crystal lattice caused by mechanochemical grinding. During the study of the effect of MgO doping and polymorphic transformations in ZrO2 ceramics on the strength properties, it was found that the main hardening effect is due to a change in the dislocation density during the formation of a ZrO2/MgO type structure. At the same time, polymorphic transformations of the m—ZrO2 → t—ZrO2 type have a greater effect on hardening at low dopant concentrations than t—ZrO2 → c—ZrO2 type transformations.

The phase formation processes in 0.25ZnO–0.25Al2O3–0.25WO3–0.25Bi2O3 ceramics with variation in the thermal annealing temperature were evaluated in this study. According to the obtained data on the phase composition dependent on the annealing temperature, the phase transformation dynamics, which can be written in the form of ZnO/Bi2O3/WO3/Al2O3 → ZnBi38O60/ZnO/Bi2WO6/WO3 → Bi2Al4O9/ZnBi38O60/Bi2WO6/ZnO/WO3 → ZnWO4/Bi2WO6/ZnAl2O4/ZnO → ZnWO4/Bi2WO6/ZnAl2O4 → Bi2WO6/ZnWO4/ZnAl2O4 → ZnAl2O4/Bi2WO6/Bi2W2O9, were established. It has been found that the formation of phases of complex oxides of the ZnWO4, Bi2WO6 and Bi2W2O9 types in the composition of ceramics leads to an increase in the density of ceramics up to 8.05–8.10 g/cm3, which positively affects the shielding efficiency and strength characteristics. According to the data on the change in strength characteristics, it was found that a change in the density of ceramics from 6.3 to 8.05–8.10 g/cm3 leads to strengthening and an increase in the crack resistance of ceramics by 75–80%, which indicates a high strength of ceramics and their increased resistance to external influences. As shown by the evaluation of the shielding characteristics, an increase in the density of ceramics due to a phase composition change leads to an increase in the shielding efficiency and a decrease in gamma intensity by a factor of 3–3.5. At the same time, on the base of the data presented, it can be concluded that ceramics obtained in the range of 900–1100 °C have both high shielding characteristics and high strength and resistance to external influences.

This work is concerned with polyethylene terephthalate (PET) saponification by different potassium compounds in various polyols as well as biodiesel’s main by-product, crude glycerol. It was established that reaction conditions (initial PET/K+ molar ratio, reaction time, etc.) could control the molecular weight of obtained oligomeric products. In ethylene glycol, depolymerization proceeds rapidly, and already at 10–30 min, PET is completely dissolved in the reaction mixture with the formation of liquid oligomers. Then, these oligomers react with potassium compounds, and after 200 min of the process, there are only solid, low-molecular-weight products (dipotassium terephthalate, monomers, and dimers). At the same time, PET saponification in pure glycerol is less effective, and solid polyether flakes could not fully decompose even after 200 min of the process. Crude glycerol takes the middle position between pure polyols. Based on the obtained data, an improved kinetic model was developed, and rate constants were estimated. This model takes into account PET saponification by potassium salts as well as direct PET glycolysis. Ethylene glycol is formed in situ by transesterification between fatty acid ethylene glycol esters and glycerol in the case of pure and crude glycerol.

The aim of this work was to study the mechanisms of polymorphic transformations in ZrO2 ceramics under irradiation with heavy ions, as well as to determine the nature of structural distortions in the case of t-ZrO2 → c-ZrO2 type transformations and associated anisotropic deformations. The samples of ZrO2 ceramics were irradiated with Kr15+ heavy ions with an energy of 150 MeV and fluences of 1011–1016 ion/cm2. During evaluation of the structural changes depending on the irradiation fluence, it was found that at low irradiation fluences (1011–1012 ion/cm2), the main role is played by deformation distortions of the crystal lattice, which have a pronounced anisotropic character. Meanwhile, at fluences above 1013 ion/cm2, the main role is played by polymorphic transformations of the t-ZrO2 → c-ZrO2 type, followed by amorphization of the damaged layer at fluences above 1015 ion/cm2. It was established that the anisotropic distortion of the crystal lattice is more pronounced along the crystallographic a axis, as well as the (011) texture orientation, which is characteristic of t-ZrO2. The polymorphic transformation processes of the t-ZrO2 → c-ZrO2 type occur at irradiation fluences of 1013–1014 ions/cm2, which are characterized by the formation of an overlap of local areas of defects that appear along the trajectory of ions in the material. The dependences of changes in the strength and thermophysical properties of ZrO2 ceramics on the irradiation fluence were obtained. The mechanisms of influence of the structural disorder and polymorphic transformations on the decrease in strength and crack resistance were established.

The article outlines findings from a comparative analysis of the effectiveness of doping CeO2 ceramics with a stabilizing additive Y2O3 on alterations in the strength and thermophysical parameters of ceramics under high-temperature irradiation with heavy ions comparable in energy to fission fragments of nuclear fuel, which allows, during high-temperature irradiation, to simulate radiation damage that is as similar as possible to the fission processes of nuclear fuel. During the studies, it was found that the addition of a stabilizing additive Y2O3 to the composition of CeO2 ceramics in the case of high-temperature irradiation causes an increase in stability to swelling and softening because of a decrease in the thermal expansion of the crystal lattice by 3–8 times in comparison with unstabilized CeO2 ceramics. It has been determined that the addition of a stabilizing additive Y2O3 leads not only to a rise in the resistance of the crystal structure to deformation distortions and swelling, but also to a decrease in the effect of thermal expansion of the crystal structure, which has an adverse effect on the structural ordering of CeO2 ceramics exposed to irradiation at high temperatures.

Ceramics based on zirconium dioxide are very important compounds for dental, implant, and structural material applications. Despite the fact that tetragonally stabilized YSZ has been well studied, the search for new compositions of zirconia-based ceramics is still in progress. The ZrO2-CeO2 system is one of the alternatives for YSZ materials, but there is conflicting experimental data on its phase composition and mechanical properties depending on the ratio of components. In this study, we investigated the phase composition, and microstructural, mechanical, and physical properties of (1 − x)∙ZrO2-x∙CeO2 (step of x = 0.05) ceramics obtained by the solid-state sintering process from micron-sized powders. For the characterization of samples, XRD, Raman spectroscopy, SEM, the Vickers Microhardness Test, and dielectric spectroscopy were implemented. The results showed that by varying the CeO2 concentration, it is possible to synthesize stable tetragonal ZrO2 at room temperature with a high microhardness HV0.05 value of ~1500, low porosity (~2.5%), and a high dielectric constant of 36. The pronounced combined effect of tetragonal phase formation, densification, and grain size reduction on the mechanical and dielectric properties of the experimental samples was investigated. Refined experimental data make it possible to synthesize high-quality zirconia–ceria ceramics for use as refractories, dispersed nuclear fuel, or solid oxide fuel cells.

In modern materials science, a considerable amount of research is focused on obtaining new ceramic materials to create efficient functional elements. Acquiring highly efficient and stable ceramic catalysts for alternative energy is an important task that demands an urgent solution. Solving this problem as fast as possible is essential, as it will facilitate the development of new technologies that can prevent future energy crises. Nickel oxide (NiO) and spinel with the composition NiAl _2 O _4 are excellent candidates as high temperature catalysts used in alternative energy applications. This paper studies the synthesis of NiO/NiAl _2 O _4 composite ceramics and the effect of high-temperature aging on their phase composition, crystalline properties, and dielectric characteristics. The study found that the phase composition and microstructure of the ceramics remain unchanged after several thermal aging cycles at 700 °C. However, the crystalline parameters and low-frequency dielectric characteristics may fluctuate significantly depending on the duration of aging. The observed variations were predominantly influenced by the microstructural features of the composite ceramics. As the average grain size increased and the phase transformations were completed, the crystalline parameters and low-frequency dielectric characteristics reached a stable state without further alteration. For NiO/NiAl _2 O _4 ceramics with a sintering temperature of 1500 °C, the highest shrinkage, low dielectric loss values and acceptable hardness were observed, indicating that the fabricated ceramics are suitable for mechanical processing. In general, the obtained composite ceramics show high temperature stability and are well-suited for use as functional elements in hydrogen energy applications.

The article presents the comprehensive analysis results of the connection between structural changes caused by the effects of deformation swelling and softening effects during high-dose irradiation with He ^2+ ions, alongside determines the kinetics of changes in structural and strength parameters contingent upon irradiation conditions (in the case of irradiation temperature variations). The interest in such studies is due to the need to study the influence of temperature factors on the diffusion mechanisms of implanted He ^2+ into the damaged layer of a high-entropy TiTaNbV alloy in the case of high-dose irradiation. At the same time, the study of such mechanisms makes it possible to determine not only the radiation resistance of TiTaNbV alloys, but also to expand the general understanding of the influence of the structural features of high-entropy alloys associated with deformation distortion of the crystal structure, which prevents diffusion and migration mechanisms of defect propagation in the damaged layer. During determination of changes in strength properties depending on irradiation conditions, it was found that irradiation temperature growth leads to both a rise in the degree of softening under high-dose irradiation and an increase in the thickness of the softened layer under high-dose irradiation. These changes indicate that at high temperatures, the diffusion of implanted ions is not restrained by structural distortions, which results in their migration to a greater depth exceeding the ion travel depth, which should be considered when designing the use of these alloys in the case of their operation in extreme conditions.

The MTS cell viability test was used to screen a mini library of natural and synthetic 1,4-naphthoquinone derivatives (1,4-NQs) from marine sources. This screening identified two highly effective compounds, U-443 and U-573, which showed potential in protecting Neuro-2a neuroblastoma cells from the toxic effects of rotenone in an in vitro model of neurotoxicity. The selected 1,4-NQs demonstrated the capability to reduce oxidative stress by decreasing the levels of reactive oxygen species (ROS) and nitric oxide (NO) in Neuro-2a neuroblastoma cells and RAW 264.7 macrophage cells and displayed significant antioxidant properties in mouse brain homogenate. Normal mitochondrial function was restored and the mitochondrial membrane potential was also regained by 1,4-NQs after exposure to neurotoxins. Furthermore, at low concentrations, these compounds were found to significantly reduce levels of proinflammatory cytokines TNF and IL-1β and notably inhibit the activity of cyclooxygenase-2 (COX-2) in RAW 264.7 macrophages. The results of docking studies showed that the 1,4-NQs were bound to the active site of COX-2, analogically to a known inhibitor of this enzyme, SC-558. Both substances significantly improved the behavioral changes in female CD1 mice with rotenone-induced early stage of Parkinson’s disease (PD) in vivo. It is proposed that the 1,4-NQs, U-443 and U-573, can protect neurons and microglia through their potent anti-ROS and anti-inflammatory activities.

Over the past decades, altruistic cyber activities of online education volunteers who share useful knowledge with other Internet users have become widespread in the Internet space. Personal and group features of such prosocial behavior, which is strongly influenced by the realization of values, have not been sufficiently studied by psychological science so far. This study continues the psychological analysis of the value-orientation sphere of online educators, focusing on competent education volunteers who deal with the Internet encyclopedia “Wikipedia” (N = 92) and the question-answer (QA) online project “Otvety” (N = 113). The following tools were used in the work: the revised Portrait Value Questionnaire (PVQ-R2R) by Sh. Schwartz adapted by T.P. Butenko, D.S. Sedova and A.S. Lipatova and the Value Orientations Techniques developed by O.I. Motkov and T.A. Ogneva (version 2). The results of the analysis provide sufficient grounds to characterize the members of both groups as indivi- duals who are productively oriented towards informational and pro-social Internet activities that are not identical in format from the perspective of transfinite altruism, for the implementation of which optimal non-hierarchical-parity conditions have been created in their reference online communities, stimulating liberty in the process of individual self-realization. It is shown that, with a high homogeneity of the value profiles of the Wikipedia authors and QA “Otvety” service experts, the internal value-related self-determination (procedural in nature) has a basal meaning for them, since the external one, set in a heteronomous position, only weakly corresponds to their freedom-seeking way of life. It is concluded that the series of theoretical and empirical psychological studies of the diverse teams of online education volunteers will make it possible, by understanding their personal and group specifics, to lay a solid foundation, which can potentially lead to global unity of people with the prospect of large-scale amplification of knowledge as one of the highest human values.

The development of the Internet contributes to the activity of education volunteers who disseminate a variety of information on the Web. This study is limited to virtual volunteers who share useful knowledge in cyberspace. Although the issues of volunteering are covered quite widely in psychological science, the volitional mechanisms that encourage online educational activities have been poorly studied. The leading role in the deployment of such prosocial behavior is played by a specific value-orientation system. The purpose of this research is to identify and describe the systems of values and value orientations of online educators, namely representatives of the expert core of the online encyclopedia “Wikipedia” (N = 96) and the question-answer (QA) online project “Otvety” (N = 47). The study is based on the value-specific (SVS, PVQ) methodology developed by Sh. Schwartz and adapted by V.N. Karandashev; the participants belong to the abovementioned expert core groups of online education volunteers. The results reveal their relatively homogeneous set of values, which is developing into an altruistic meta-orientation towards autonomously given and situationally different dissemination of knowledge aimed at providing information (as a public utility) and regulated by self-transcendence and openness to changes. Intersubjective (in terms of normative ideals and individual priorities) and intergroup (in terms of communities) value-related comparison of the study participants - Wikipedia authors and QA “Otvety” service experts - optionally show that the Wikipedians are more inclined to avoid saturated social relationships (being socially inert), however, are much more hedonistic about life than the QA-experts. At the same time, both groups are brought together as close as possible by the radical condemnation of any factors that interfere with social harmony and limit the freedom to manifest oneself as a person. Based on the obtained results, it can be concluded that further understanding of the personal and group characteristics of education volunteers can expand the scope of education; therefore, in subsequent studies, it is proposed to use successive psychodiagnostic methods that measure value specificity in a psychosocial context.

This publication continues the experience of covering the work of the Scientific and Meth­odological Council under the Prosecutor of the Omsk Region, among the main tasks of which remains the development and discussion, together with representatives of legal science, of sound recommenda­tions on problematic issues of prosecutorial supervision, legislation and law enforcement practice, legal advisory opinions on issues arising in prosecutorial practice. In this regard, the article proposes to dis­cuss certain topical problems of law enforcement practice raised at one of the last meetings of the Scien­tific and Methodological Council under the Prosecutor of the Omsk Region. Thus, based on a systematic analysis of errors in the implementation of the institution of a judicial fine, it is proposed to provide prosecutors with systematic supervision over compliance with the requirements of the law when it is ap­plied, which requires a more thorough study of criminal cases, as well as a proper initiative to establish the circumstances associated with the application of a judicial fine, and timely challenging unfounded court decisions. In addition, the practice of law enforcement highlights the fundamental problem of a unified interpretation of the grounds for terminating a criminal case (criminal prosecution) against a person who has committed an act prohibited by criminal law in a state of insanity. Based on the analy­sis of legal situations and various approaches to their resolution, the article argues for the need to make a decision on the studied criminal cases on the grounds of paragraph 4 of part 1 of Art. 24 of the Criminal Procedure Code of the Russian Federation in connection with the death of a person involved in criminal proceedings. In other similar situations, but related to the criminal prosecution of these persons, the deci­sion must be made taking into account the specific circumstances of the criminal case.

The aim of this work is to study the hydrogenation processes in lithium-containing ceramics under high-temperature irradiation. Irradiation was carried out with protons with an energy of 1 MeV and fluences of 1015–1017 ion/cm2 at irradiation temperatures of 300–1000 K. The choice of irradiation conditions is due to the possibility of simulation of the radiation damage accumulation processes in the near-surface layer of Li2TiO3 ceramics, as well as establishing the dependences of changes in structural parameters during temperature heating of samples during irradiation. It has been established that at irradiation fluences of 1015–1016 ion/cm2, the formation of dislocation defects is observed, the density of which has a pronounced dependence on the irradiation temperature. At irradiation fluence above 5 × 1016 ion/cm2, an increase in the crystal structure deformation is observed, due to swelling processes as a result of implanted hydrogen accumulation in the near-surface layer structure. At the same time, an increase in the irradiation temperature leads to a decrease in the swelling value, which is due to the accelerated migration of implanted hydrogen in the near-surface layer and its release through the existing pores. Results of mechanical tests showed that the swelling of the crystal structure and its deformation leads to embrittlement and a partial decrease in the strength of the near-surface layer. The obtained research results will further allow us to evaluate the resistance of lithium ceramics to the processes of hydrogenation and destruction as a result of the formation of gas-filled cavities in the structure of the near-surface layer.

Interest in the modification of zirconium-containing ceramics is rooted in their great prospects for application as materials for creating inert matrices of dispersed nuclear fuel, which can replace traditional fuel containing uranium dioxide, as well as increase the degree of its burnup. Moreover, among the variety of different types of ceramics offered, zirconium dioxide is the most promising, since it has higher thermal conductivity values compared to other types of ceramics, as well as low volumetric thermal expansion. Moreover, the key limitations in the application of these types of ceramics as materials for creating inert matrices are polymorphic transformations, which have a negative impact on changes in the properties of ceramics under external influences. The evaluation results of the impact of change in the ZrO2 ceramics’ phase composition on the radiation damage resistance when subjected to irradiation with heavy ions, comparable in energy to fission fragments, are presented. The objects of study were samples of ZrO2 ceramics doped with MgO, the variation in the concentration of which leads to an acceleration of the processes of polymorphic transformations during thermal sintering, as well as the formation of a ZrO2/MgO-type structure with inclusions in the form of MgO grains. The results of the irradiation effect on the stability of the crystal structure of ceramics to deformation swelling due to the accumulation of deformation inclusions showed that ceramics with a monoclinic structure type are the least stable, for which, in the case of high irradiation fluences, the accumulation of deformation distortions leads to polymorphic transformations of the m—ZrO2 → t—ZrO2 type. During the evaluation of the irradiation effect on the change in mechanical properties and the softening degree, it was found that phase transformations of the m—ZrO2 → t—ZrO2 and t—ZrO2 → c—ZrO2 types lead to an increase in crack resistance by 1.5–2.0 times. Meanwhile, the formation of a structure of the ZrO2/MgO type with inclusions in the form of MgO grains in the interboundary space results in a softening resistance growth by over 7-fold. During tests for determining thermophysical parameters, as well as maintaining stability to crystal structure thermal expansion during prolonged thermal exposure, it was found that phase transformations associated with polymorphic transformations of the t—ZrO2 → c—ZrO2 type led to the preservation of the stability of thermophysical properties, even in the case of high irradiation fluences.

Conducting high-temperature tests on ceramics-containing lithium, which are employed as tritium breeding materials, plays a crucial role in comprehending their ability to withstand degradation and maintain their strength properties throughout operation. From the standpoint of fusion research, it is imperative to grasp these phenomena in order to guarantee the safety and effectiveness of reactors. Additionally, these factors could impact the choice of particular materials and designs for blanket materials. The primary objective of this research is to evaluate alterations in the strength characteristics of ceramics-containing lithium when subjected to high-temperature thermal stability tests, while also preserving the hardness stability and resistance to cracking in ceramics subjected to cyclic tests. Lithium-containing ceramics based on lithium titanate (Li2TiO3), lithium orthosilicate (Li4SiO4), and lithium methacyrconate (Li2ZrO3), having a high structural ordering degree and good strength properties, were chosen as objects for assessing resistance to high-temperature degradation. During the studies, it was discovered that the presence of interphase boundaries in the composition of ceramics linked to the development of impurity phases results in crack resistance growth during long-term high-temperature tests simulating the stress effect on the material. At the same time, an assessment of high-temperature aging as a result of modeling destruction processes showed that ceramics based on lithium metazirconate are the most resistant to degradation of strength properties. By simulating high-temperature aging processes, it became feasible to establish connections between structural alterations resulting from the thermal expansion of the crystal lattice and oxygen migration phenomena occurring at elevated temperatures. These factors collectively contribute to a detrimental reduction in the strength properties of ceramics-containing lithium.