N.A. VASILYEV’S HISTORIOGRAPHY IN THE MIRROR OF SOCIAL AND SOCIAL-POLITICAL DOCTRINES OF THE XX CENTURY

Цель. Предметом статьи выступает историко-философская доктрина Н.А.Васильева, изложенная в его диссертационном исследовании. Раскрытие методологической стороны данной доктрины является целью настоящей работы. В качестве примера приведена концепция сравнительного обществознания Васильева.Метод или методология проведения работы. Основу исследования составляет сравнительно-исторический метод, а также общенаучные методы дедукции, индукции и аналогии, метод классификации, применимый как в естествознании, так и в общественных науках.Результаты. Результаты работы заключаются в том, что автором выявлены методологические выводы русского мыслителя Н.А. Васильева, показано место идей творца систем логической неклассичности в методологии гуманитарных наук XX в.Область применения результатов. Итоги исследования могут быть использованы при преподавании общественных дисциплин, в первую очередь истории и социологии, а также в целях определения межпредметных связей между общественными и естественными науками.Purpose. This article covers the historic and philosophic doctrine by Nicolai A. Vasiliev that he included in his thesis research. This article is aimed at exploring the methodological aspect of the above doctrine through the example of the concept of comparative sociology developed by Nicolai A. Vasiliev.Methodology. The core method used in this research is the comparative historical method, though other scientific methods (like deduction, induction, and analogy, a method of classification applicable both in natural sciences and in social sciences) are also used.Results. The results of this study are that its author has identified the methodological conclusions reached by Nicolai A. Vasiliev, the creator of the non-classical logic systems, as well as the place that his ideas hold in the methodology of the humanities in the 20th century.Principal implications. The results of this study can be applied in teaching the social sciences, first and foremost history and sociology, and also in order to determine the intersubject connections between social and natural sciences

Risk modeling in the aviation industry as a factor of sustainable development

Research by leading economists has revealed that risks in the aviation industry affect the forecasting models of regional sustainable development. The current study is devoted to the development of approaches to risk assessment on the example of European airlines. This problem has become very problematic after several recent financial crises, when airlines around the world were going through difficult times, and dozens of them had to go bankrupt, receive financial assistance from governments or find their salvation in mergers or acquisitions with larger players in the market with the support of governments. Since the beginning of the pandemic, airlines around the world have faced many more serious problems that have forced them to stop most of their passenger flights due to restrictions aimed at reducing the incidence. Unlike other financial crises, the pandemic faces the most serious problem of uncertainty, since it is difficult to predict how the virus will behave and when it will stop. This study is aimed at developing approaches that can help identify and predict possible airline risks and establish regulatory values of significant indicators for this industry in Europe

Critical fluctuations in superconductors and the magnetic field penetration depth

The superconducting transition is studied within the one-loop renormalization group in fixed dimension $D=3$ and at the critical point. A tricritical behavior is found, and for $\kappa > \kappa_c$, an attractive charged fixed point, distinct from that of a neutral superfluid. The critical exponents of the continuous transition are evaluated, and it is shown that the anomalous dimension of the gauge field equals unity. This implies the proportionality of the magnetic field penetration depth and the superconducting correlation length below the transition. The penetration depth exponent is nonclassical. We argue that it can not be extracted from the dual theory in a straightforward manner since it is not renormalized by fluctuations of the dual field.Comment: 12 pages, LaTex, two figures available upon reques

Core-shell magnetoactive PHB/gelatin/magnetite composite electrospun scaffolds for biomedical applications

Novel hybrid magnetoactive composite scaffolds based on poly(3-hydroxybutyrate) (PHB), gelatin, and magnetite (Fe3O4) were fabricated by electrospinning. The morphology, structure, phase composition, and magnetic properties of composite scaffolds were studied. Fabrication procedures of PHB/gelatin and PHB/gelatin/Fe3O4 scaffolds resulted in the formation of both core-shell and ribbon-shaped structure of the fibers. In case of hybrid PHB/gelatin/Fe3O4 scaffolds submicron-sized Fe3O4 particles were observed in the surface layers of the fibers. The X-ray photoelectron spectroscopy results allowed the presence of gelatin on the fiber surface (N/C ratio–0.11) to be revealed. Incubation of the composite scaffolds in saline for 3 h decreased the amount of gelatin on the surface by more than ~75%. The differential scanning calorimetry results obtained for pure PHB scaffolds revealed a characteristic melting peak at 177.5 °C. The presence of gelatin in PHB/gelatin and PHB/gelatin/Fe3O4 scaffolds resulted in the decrease in melting temperature to 168–169 °C in comparison with pure PHB scaffolds due to the core-shell structure of the fibers. Hybrid scaffolds also demonstrated a decrease in crystallinity from 52.3% (PHB) to 16.9% (PHB/gelatin) and 9.2% (PHB/gelatin/Fe3O4). All the prepared scaffolds were non-toxic and saturation magnetization of the composite scaffolds with magnetite was 3.27 ± 0.22 emu/g, which makes them prospective candidates for usage in biomedical applications

Electrospun magnetic composite poly-3-hydroxybutyrate/magnetite scaffolds for biomedical applications: composition, structure, magnetic properties, and biological performance

Magnetically responsive composite polymer scaffolds have good potential for a variety of biomedical applications. In this work, electrospun composite scaffolds made of polyhydroxybutyrate (PHB) and magnetite (Fe3O4) particles (MPs) were studied before and after degradation in either PBS or a lipase solution. MPs of different sizes with high saturation magnetization were synthesized by the coprecipitation method followed by coating with citric acid (CA). Nanosized MPs were prone to magnetite-maghemite phase transformation during scaffold fabrication, as revealed by Raman spectroscopy; however, for CA-functionalized nanoparticles, the main phase was found to be magnetite, with some traces of maghemite. Submicron MPs were resistant to the magnetite-maghemite phase transformation. MPs did not significantly affect the morphology and diameter of PHB fibers. The scaffolds containing CA-coated MPs lost 0.3 or 0.2% of mass in the lipase solution and PBS, respectively, whereas scaffolds doped with unmodified MPs showed no mass changes after 1 month of incubation in either medium. In all electrospun scaffolds, no alterations of the fiber morphology were observed. Possible mechanisms of the crystalline-lamellar-structure changes in hybrid PHB/Fe3O4 scaffolds during hydrolytic and enzymatic degradation are proposed. It was revealed that particle size and particle surface functionalization affect the mechanical properties of the hybrid scaffolds. The addition of unmodified MPs increased scaffolds' ultimate strength but reduced elongation at break after the biodegradation, whereas simultaneous increases in both parameters were observed for composite scaffolds doped with CA-coated MPs. The highest saturation magnetization-higher than that published in the literature-was registered for composite PHB scaffolds doped with submicron MPs. All PHB scaffolds proved to be biocompatible, and the ones doped with nanosized MPs yielded faster proliferation of rat mesenchymal stem cells. In addition, all electrospun scaffolds were able to support angiogenesis in vivo at 30 days after implantation in Wistar rats

Suppressing quantum errors by scaling a surface code logical qubit

Practical quantum computing will require error rates that are well below what is achievable with physical qubits. Quantum error correction offers a path to algorithmically-relevant error rates by encoding logical qubits within many physical qubits, where increasing the number of physical qubits enhances protection against physical errors. However, introducing more qubits also increases the number of error sources, so the density of errors must be sufficiently low in order for logical performance to improve with increasing code size. Here, we report the measurement of logical qubit performance scaling across multiple code sizes, and demonstrate that our system of superconducting qubits has sufficient performance to overcome the additional errors from increasing qubit number. We find our distance-5 surface code logical qubit modestly outperforms an ensemble of distance-3 logical qubits on average, both in terms of logical error probability over 25 cycles and logical error per cycle ($2.914\%\pm 0.016\%$ compared to $3.028\%\pm 0.023\%$). To investigate damaging, low-probability error sources, we run a distance-25 repetition code and observe a $1.7\times10^{-6}$ logical error per round floor set by a single high-energy event ($1.6\times10^{-7}$ when excluding this event). We are able to accurately model our experiment, and from this model we can extract error budgets that highlight the biggest challenges for future systems. These results mark the first experimental demonstration where quantum error correction begins to improve performance with increasing qubit number, illuminating the path to reaching the logical error rates required for computation.Comment: Main text: 6 pages, 4 figures. v2: Update author list, references, Fig. S12, Table I

Non-Abelian braiding of graph vertices in a superconducting processor

Indistinguishability of particles is a fundamental principle of quantum mechanics. For all elementary and quasiparticles observed to date - including fermions, bosons, and Abelian anyons - this principle guarantees that the braiding of identical particles leaves the system unchanged. However, in two spatial dimensions, an intriguing possibility exists: braiding of non-Abelian anyons causes rotations in a space of topologically degenerate wavefunctions. Hence, it can change the observables of the system without violating the principle of indistinguishability. Despite the well developed mathematical description of non-Abelian anyons and numerous theoretical proposals, the experimental observation of their exchange statistics has remained elusive for decades. Controllable many-body quantum states generated on quantum processors offer another path for exploring these fundamental phenomena. While efforts on conventional solid-state platforms typically involve Hamiltonian dynamics of quasi-particles, superconducting quantum processors allow for directly manipulating the many-body wavefunction via unitary gates. Building on predictions that stabilizer codes can host projective non-Abelian Ising anyons, we implement a generalized stabilizer code and unitary protocol to create and braid them. This allows us to experimentally verify the fusion rules of the anyons and braid them to realize their statistics. We then study the prospect of employing the anyons for quantum computation and utilize braiding to create an entangled state of anyons encoding three logical qubits. Our work provides new insights about non-Abelian braiding and - through the future inclusion of error correction to achieve topological protection - could open a path toward fault-tolerant quantum computing

Urban nature protection measures evaluated by opinion poll respondents

The article addresses the findings of the poll, conducted by lecturers and students of the National Research Moscow State University of Civil Engineering. The poll objective was to identify the level of ecological culture demonstrated by the residents of Moscow, the Russian capital and a megacity. Residents of its old and new administrative districts were among the respondents. The author verifies the scope and extension of such concepts as ecological culture and environmental safety, sheds light on the structure of environmental safety. The responses, given by the respondents, are used in the rating of environmental hazards of which air pollution is a number one threat. Moreover, the poll addressed such problems as domestic waste removal, pollution of Moscow rivers, lakes, ponds and other water bodies with waste water. Besides the polling method, employed by the author, he used the retrospective analysis of news items. Moreover, environmental monitoring results and opinions, expressed by the authors of research articles, were analyzed; methods of deduction, induction, classification and split of concepts were also used by the author

The quality of environmental planning in the assessment of residents of Moscow

The paper analyzes the results of a sociological survey conducted in February-March 2020 by teachers and students of NRU MSUCE on the topic “Urboecological planning and design in the assessment of the young generation of townspeople.” The survey was conducted among young people permanently residing in the metropolitan area, including in the territory of New Moscow. The study identified the main challenges and problems facing city authorities and civil society in the in the metropolitan area and Moscow region. Some measures of urban ecological planning and design are considered. The author analyzes the components of the ecological culture of the townspeople, in the structure of which he distinguishes ecological education, ecological upbringing and ecological behavior. The results of the study can be used in planning and conducting environmental protection measures both in large metropolitan areas, in particular in Moscow, and in medium-sized settlements