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Dark matter may consist of axion-like particles (ALPs). When polarized electromagnetic radiation passes through the dark-matter media, interaction with background ALPs affects the polarization of photons. The condensate of axionic dark matter experiences periodic oscillations, and the period of the oscillations is of order of years for ultra-light dark matter. This would result in observable periodic changes in the polarization plane, determined by the phases of the ALP field at the Earth and at the source. In this paper, we use recent polarimetric observations of the HL Tauri protoplanetary disk performed in different years to demonstrate the lack of changes of polarization angles, and hence to constrain masses and photon couplings of the hypothetical axion-like ultralight dark matter., Comment: 4 pages, 2 figures, results in sec. III were corrected. Submitted to Phys. Rev. D

Infall of cold dark matter on a galaxy may result in caustic rings where the particle density is enhanced. They may be searched for as features in the galactic rotation curves. Previous studies suggested the evidence for these caustic rings with universal, that is common for different galaxies, parameters. Here we test this hypothesis with a large independent set of rotation curves by means of an improved statistical method. No evidence for universal caustic rings is found in the new analysis., Comment: 9 pages, 4 figures

Infall of cold dark matter on a galaxy may result in caustic rings where the particle density is enhanced. They may be searched for as features in the galactic rotation curves. Previous studies suggested the evidence for these caustic rings with universal, that is common for different galaxies, parameters. Here we test this hypothesis with a large independent set of rotation curves by means of an improved statistical method. No evidence for universal caustic rings is found in the new analysis., Comment: 9 pages, 4 figures. V2: comparison with previous studies extended; version accepted by Phys. Lett. B

The process of an unstable plastic flow associated with the strain rate sensitivity of mechanical properties was studied in porous 316L austenitic steel samples manufactured by laser powder bed fusion (L-PBF). Different micromechanisms of deformation and fracture of porous samples dependent on strain rate were found. It was found that despite the porosity, the specimens showed high strength, which increased with the loading rate. Porosity led to lower ductility of the studied specimens, in comparison with literature data for low porous 316L L-PBF samples and resulted in de-localization of plastic deformation. With an increase in strain rate, nucleation of new pores was less pronounced, so that at the highest strain rate of 8 × 10-3s-1, only pore coalescence was ob-served as the dominating microscopic mechanism of ductile fracture. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

The structure and phase composition of a series of heat-resistant alloys of the Co–Al–Mo–Nb system were studied by methods of differential scanning calorimetry (DSC) and scanning microscopy. The effect of the niobium and molybdenum content on the phase composition of the alloy and the temperature boundaries of the region of existence of the Co3 (Al, Mo, Nb) intermetallic phase are determined., Проведено исследование структуры и фазового состава серии жаропрочных сплавов системы Co–Al–Mo–Nb методами дифференциальной сканирующей калориметрии (ДСК) и растровой микроскопии. Определено влияние содержания ниобия и молибдена на фазовый состав сплава и температурные границы области существования интерметаллидной фазы Co3 (Al, Mo, Nb).

The present article is devoted to a discussion of the crisis of humanism and prospects for a post-anthropocentric society. The evolution of humanism is traced as a broad cultural phenomenon that affects all spheres of society. The author sets out to show that the crisis of humanism is associated not only with philosophical criticism from the perspectives of trans- and post-humanism, but also with the prospects for a society in which humanistic ideas about a person as a bodily- and mentally-autonomous being continue to predominate. In this regard, various ethical and philosophical concepts are considered that seemingly point to the inevitability of going beyond the limits of anthropocentrism. However, one particular problem that emerges is either ignored by many authors or remains to be properly resolved. This problem is associated with the prospect of losing the capability of “metamorphosis” due to the latest human technologies for universal communication (empathy and understanding) along with the destruction of the fragile global “lifeworld”. The destruction of this lifeworld is fraught with alienation and the multiplication of planetary risks. The author proposes that the problem of unpredictability and the danger of manmade interventions in human nature can best be approached by considering the hypothetical posthuman in close relationship with the social whole. This philosophical “optics” can be borrowed from the philosophy of personalism, understood here as the set of philosophical attitudes that affirm the highest value of a personality as a transcending being, involved in a timeless dialogue with other personalities.

Смена уровней фокализации, изображение первичного и вторичного нарраторов, присутствие голоса автора и авторских отступлений в нарративном дискурсе, недигиетическое повествование – все эти стратегии, найденные в творчестве Д. Н. Мамина-Сибиряка и рассмотренные на примере конкретных рассказов, позволяют понять их роль в творчестве уральского писателя-летописца, а также проследить их влияние на русский натурализм., Тhe change of focalization levels, the image of the primary and secondary narrators, the presence of the author's voice and the author's digressions in the narrative discourse, nondigytic narration – all of these strategies found and considered in the works of D.N. Mamina-Sibiryak (using specific stories as an example) makes it possible to understand their influence both on Russian naturalism and on the work of the Ural chronicler-writer.

The structure and residual elastic stresses in 3D printed (Selective laser melting) Ti-6A1-4V samples after the low-frequency vibration processing were investigated. The studied samples were manufactured horizontally in respect to the building platform. Different vibration oscillations modes (vertical, horizontal, and elliptical) were chosen for study. The oscillations were done with frequency of 16 Hz, and a processing time was 20 minutes. Studies shown that 3D printed samples had a high level of residual elastic stresses, which were changed after vibration treatment. The influence of the low-frequency processing on the phase composition of the alloy was found. © Published under licence by IOP Publishing Ltd.

This article analyzes the main priorities of the strategy of Russia's state policy in the tourist industry, considers the possibility of diversifying the project activities. The study was given a primary qualitative assessment of the socio-cultural potential of urbanized areas, the importance of including Russian cities in the agenda of strategic development was identified., В данной статье анализируются основные приоритеты стратегии государственной политики России в туристской отрасли, рассматривается возможность диверсификации проектной деятельности. В рамках исследования была дана первичная квалиметрическая оценка социокультурного потенциала урбанизированных территорий, была обозначена важность включения городов России в повестку стратегического развития.

Morphology of the g′-precipitations in the Co–7.9Al–6.8W (ат. %) alloy in depending on heat treatments is investigated. Annealing at temperature just higher than the g′-solvus one allowed us to conserve the supersaturated g‑phase. The size and morphology of the hardening phase particles depends on the aging temperature., Проведено исследование влияния термообработки на структуру и фазовый состав сплава Co–7,9Al–6,8W (ат. %). Отжиг выше температуры γ′-сольвуса с последующей закалкой приводит к образованию пересыщенного твердого раствора кобальта. Температура старения оказывает сильное влияние на размер и морфологию частиц упрочняющей γ-фазы.

The problem which is considered in this article is the influence of terrorism on the development of North Caucasian Federal district touristic sphere. The author gives an accent on the negative tendencies of the region, urgency of the problem in the context of the world, necessity of a thorough analysis of the problem on the level of state. The methodology of this research includes system approach and structural analysis. There is a special attention to the statistics and social researches, normative documents, mass media materials, scientific articles of the other authors. The results of the following research make to possible to come to conclusion that this problem should be explored more thoroughly., В данной статье рассматривается проблема влияния терроризма на развитие туристского сектора Северо-Кавказского федерального округа. Автор акцентирует внимание на современных негативных тенденциях в регионе, актуальности проблемы в мировом контексте, необходимости более тщательного анализа проблемы на государственном уровне. Методология исследования включает в себя системный подход и структурный анализ. Большое внимание уделяется статистическим данным и социологическим исследованиям, нормативным документам, материалам СМИ, научным статьям других авторов. Результаты исследования позволили сделать вывод о том, что проблема в дальнейшем должна быть изучена более тщательным образом.

The influence of the irradiation with neutrons, Kr+ (245 MeV) and Bi+ (710 MeV) ions on the optical and electrical properties of high-resistivity, high-purity 4H-SiC epitaxial layers grown by chemical vapor deposition was investigated using photoluminescence and deep-level transient spectroscopy. Electrical characteristics were studied using Al and Cr Schottky barriers as well as p(+)-n-n(+) diodes fabricated by Al ion implantation on this epitaxial layers. It was found that both "light" neutrons and high energy heavy ions introduced identical defect centers in 4H-SiC. So, even at extremely high density of the ionization energy of 34 keV/mn, typical for Bi+ ion bombardment, damage structure formation in SiC single crystal is governed by energy loss in elastic collisions., QC 20111012

The radiation-induced defect formation in high purity 4H-SiC CVD epitaxial layers and changes in the electrical properties of diode structures based on its after irradiation with different fluences I MeV neutrons were investigated at temperatures as high as 700 K. The Z(1), deep center, typical for 4H-SiC, was observed both in the initial and irradiated samples. The presence and number of different deep levels increased with the neutron fluence. The rectifying properties of the diode structures disappeared after neutron irradiation with fluence of 6.2x10(14) cm(-2). However, the diode structures that had been degraded after irradiation with fast neutrons, recovered their properties at the temperature of 700 K., QC 20141208

Photoluminescence and deep-level transient spectroscopy are used to study the effect of irradiation with fast neutrons and high-energy Kr (235 MeV) and Bi (710 MeV) ions on the optical and electrical properties of high-resistivity high-purity n-type 4H-SiC epitaxial layers grown by chemical vapor deposition. Electrical characteristics were studied using the barrier structures based on these epitaxial layers: Schottky barriers with Al and Cr contacts and p(+)-n-n(+) diodes fabricated by Al ion implantation. According to the experimental data obtained, neutrons and high-energy ions give rise to the same defect-related centers. The results show that, even for the extremely high ionization density (34 keV/nm) characteristic of Bi ions, the formation of the defect structure in SiC single crystals is governed by energy losses of particles due to elastic collisions., QC 20100525 QC 20111102

The effect of irradiation with 1-MeV neutrons on electrical properties of Al-based Schottky barriers and p(+)-n-n(+) diodes doped by ion-implantation with Al was studied; the devices were formed on the basis of high-resistivity, pure 4H-SiC epitaxial layers possessing n-type conductivity and grown by vapor-transport epitaxy. The use of such structures made it possible to study the radiation defects in the epitaxial layer at temperatures as high as 700 K. Rectifying properties of the diode structures were no longer observed after irradiation of the samples with neutrons with a dose of 6 x 10(14) cm(-2); this effect is caused by high (up to 50 GOmega) resistance of the layer damaged by neutron radiation. However, the diode characteristics of irradiated p(+)-n-n(+) structures were partially recovered after an annealing at 650 K., QC 20100525

The characteristics of boron incorporation and the resultant electrical behaviour have been studied for sublimation grown epilayers. Some factors which influence are the purity of the source material, growth temperature and growth time. The electrical activity of the shallow and deep level of boron has been investigated in relation to growth parameters and from the results the nature of the deep boron complex is discussed. The use of TaC coated graphite crucibles resulted in a decrease of the Z(1,2) concentration to less than low E13 cm(-3) which is the concentration obtained using graphite crucibles.

Results of complex studies of structural, optical, and electrical characteristics of 4H-SiC n-type low-doped epitaxial layers grown by the chemical vapor deposition (CVD) method are presented. Characteristics of CVD layers grown on commercial wafers with and without a thin (<0.1 mum) buffer layer grown by liquid phase epitaxy (LPE) between the commercial wafer and CVD epitaxial layer were compared. It has been shown that the LPE filling process caused a significant improvement in the structural quality of CVD layers. Cathodoluminescence (CL) data and electrical characteristics of Schottky barriers (SB) revealed that the LPE layer also made the concentration profiles of the uncompensated donors and recombination centers for holes as well as the hole diffusion lengths more uniform over the CVD layer. According to CL and secondary ion mass-spectroscopy measurements the presence of aluminum as an impurity was detected in initial commercial wafers, as well as having LPE and CVD epitaxial layers. Forward current-voltage characteristics of SBs formed on CVD layers with and without a LPE buffer layer followed an exponential relationship with an ideality factor of 1.04-1.06 over six to seven orders of magnitude in current density. A noticeable increase of the breakdown voltage was also observed in samples with a LPE layer., QC 20100525

A major challenge presently is not only to identify the genetic polymorphisms increasing risk to diseases, but to also find out factors and mechanisms, which can counteract a risk genotype by developing a resilient phenotype. The objective of this study was to examine acquired and innate vagal mechanisms that protect against physical challenges and haemorrhages in 19 athletes and 61 non-athletes. These include examining change in heart rate variability (HF-HRV; an indicator of vagus activity) in response to orthostatic challenge, platelet count (PLT), mean platelet volume (MPV), and single-nucleotide polymorphisms in genes that encode several coagulation factors, PAI-1, and MTHFR. Individual differences in PLT and MPV were significant predictors, with opposite effects, of the profiles of the HF-HRV changes in response to orthostasis. Regular physical training of athletes indirectly (through MPV) modifies the genetic predisposing effects of some haemostatic factors (PAI-1 and MTHFR) on vagal tone and reactivity. Individual differences in vagal tone were also associated with relationships between Factor 12 C46T and Factor 11 C22771T genes polymorphisms. This study showed that genetic predispositions for coagulation are modifiable. Its potential significance is promoting advanced protection against haemorrhages in a variety of traumas and injuries, especially in individuals with coagulation deficits.

A mathematical model of the dynamic behavior of phosphorylase kinase was devised. Based on the results obtained, the function of this protein is discussed. It is suggested that phosphorylase kinase doses in a cAMP-dependent manner additional portions of glucoso-l-phosphate, which the muscle cell receives in response to contraction.

A systemic study of the mechanisms of motor activity of paramecium was carried out. The movements of paramecium responding to various influences were photographed. The analysis of the data revealed the time dependences of the rate of movement, rate of rotation, and the radius and the pitch of the helix trajectory. Mathematical models of the membrane and a unit that transforms the calcium signal to programs of regulating the effectors were constructed. A system of equations for constructing the trajectory of movement was proposed. It is concluded that the biomolecular system that involves calmodulin, calmodulin-dependent ionic channels, adenylate cyclase, guanylate cyclase, phosphodiesterases, Ca(2+)-calmodulin, cAMP, cGMP-dependent protein kinases, and phosphoprotein phosphatases is capable of regulating motor reactions necessary for complex maneuvering of paramecium under various conditions.

A mathematical model of the dynamic behavior of phosphorylase kinase was devised. Based on the results obtained, the function of this protein is discussed. It is suggested that phosphorylase kinase doses in a cAMP-dependent manner additional portions of glucoso-1-phosphate, which the muscle cell receives in response to contraction.

A systemic study of the mechanisms of motor activity of paramecium was carried out. The movements of paramecium responding to various influences were photographed. The analysis of the data revealed the time dependences of the rate of movement, rate of rotation, and the radius and the pitch of the helix trajectory. Mathematical models of the membrane and a unit that transforms the calcium signal to programs of regulating the effectors were constructed. A system of equations for constructing the trajectory of movement was proposed. It is concluded that the biomolecular system that involves calmodulin, calmodulin-dependent ionic channels, adenylate cyclase, guanylate cyclase, phosphodiesterases, Ca2+-calmodulin, cAMP, cGMP-dependent protein kinases, and phosphoprotein phosphatases is capable of regulating motor reactions necessary for complex maneuvering of paramecium under various conditions.

A major challenge presently is not only to identify the genetic polymorphisms increasing risk to diseases, but to also find out factors and mechanisms, which can counteract a risk genotype by developing a resilient phenotype. The objective of this study was to examine acquired and innate vagal mechanisms that protect against physical challenges and haemorrhages in 19 athletes and 61 non-athletes. These include examining change in heart rate variability (HF-HRV; an indicator of vagus activity) in response to orthostatic challenge, platelet count (PLT), mean platelet volume (MPV), and single-nucleotide polymorphisms in genes that encode several coagulation factors, PAI-1, and MTHFR. Individual differences in PLT and MPV were significant predictors, with opposite effects, of the profiles of the HF-HRV changes in response to orthostasis. Regular physical training of athletes indirectly (through MPV) modifies the genetic predisposing effects of some haemostatic factors (PAI-1 and MTHFR) on vagal tone and reactivity. Individual differences in vagal tone were also associated with relationships between Factor 12 C46T and Factor 11 C22771T genes polymorphisms. This study showed that genetic predispositions for coagulation are modifiable. Its potential significance is promoting advanced protection against haemorrhages in a variety of traumas and injuries, especially in individuals with coagulation deficits.

A mathematical model of the dynamic behavior of phosphorylase kinase was devised. Based on the results obtained, the function of this protein is discussed. It is suggested that phosphorylase kinase doses in a cAMP-dependent manner additional portions of glucoso-1-phosphate, which the muscle cell receives in response to contraction.

A systemic study of the mechanisms of motor activity of paramecium was carried out. The movements of paramecium responding to various influences were photographed. The analysis of the data revealed the time dependences of the rate of movement, rate of rotation, and the radius and the pitch of the helix trajectory. Mathematical models of the membrane and a unit that transforms the calcium signal to programs of regulating the effectors were constructed. A system of equations for constructing the trajectory of movement was proposed. It is concluded that the biomolecular system that involves calmodulin, calmodulin-dependent ionic channels, adenylate cyclase, guanylate cyclase, phosphodiesterases, Ca2+-calmodulin, cAMP, cGMP-dependent protein kinases, and phosphoprotein phosphatases is capable of regulating motor reactions necessary for complex maneuvering of paramecium under various conditions.

A systemic study of the mechanisms of motor activity of paramecium was carried out. The movements of paramecium responding to various influences were photographed. The analysis of the data revealed the time dependences of the rate of movement, rate of rotation, and the radius and the pitch of the helix trajectory. Mathematical models of the membrane and a unit that transforms the calcium signal to programs of regulating the effectors were constructed. A system of equations for constructing the trajectory of movement was proposed. It is concluded that the biomolecular system that involves calmodulin, calmodulin-dependent ionic channels, adenylate cyclase, guanylate cyclase, phosphodiesterases, Ca(2+)-calmodulin, cAMP, cGMP-dependent protein kinases, and phosphoprotein phosphatases is capable of regulating motor reactions necessary for complex maneuvering of paramecium under various conditions.

A mathematical model of the dynamic behavior of phosphorylase kinase was devised. Based on the results obtained, the function of this protein is discussed. It is suggested that phosphorylase kinase doses in a cAMP-dependent manner additional portions of glucoso-l-phosphate, which the muscle cell receives in response to contraction.