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This paper explores the experiences of six teacher learners and one teacher educator in a graduate course on aesthetic education at a Midwestern university in the U.S. Using collective autoethnography and arts-practice research, the researcher/participants examine how aesthetic experiences were activated in the learning environment and how this activation supported the development of transformational rethinking that led to the changing of formed habits of teaching. Findings reveal how aesthetic teacher education can be therapeutic, aid in building connections between the teacher and students (and among students), inspire wonder and discovery, facilitate the valuing and including of cultural and linguistic backgrounds of students, compel new perspectives, and promote attunement to process.

Single photon emitters (SPEs) in hexagonal boron nitride (hBN) are elementary building blocks for room-temperature on-chip quantum photonic technologies. However, fundamental challenges, such as slow radiative decay and nondeterministic placement of the emitters, limit their full potential. Here, we demonstrate large-area arrays of plasmonic nanoresonators (PNRs) for Purcell-induced room-temperature SPEs by engineering emitter-cavity coupling and enhancing radiative emission. Gold-coated silicon pillars with an alumina spacer enable a 10-fold local-field enhancement in the emission band of native hBN defects. We observe bright SPEs with an average saturated emission rate surpassing 5 million counts per second, an average lifetime of

All-optical tunability of semiconductor metasurfaces offers unique opportunities for novel time-varying effects, including frequency conversion and light trapping. However, the all-optical processes often induce optical absorption that fundamentally limits the possible dynamic increase of their quality factor (Q-boosting). Here, we propose and numerically demonstrate the concept of large Q-boosting in a single-material metasurface by dynamically reducing its structural anisotropy on a femtosecond timescale. This balance is achieved by excitation with a structured pump and takes advantage of the band-filling effect in a GaAs direct-bandgap semiconductor to eliminate the free-carrier-induced loss. We show that this approach allows a dynamic boosting of the resonance quality factor over orders of magnitude, only limited by the free-carrier relaxation processes. The proposed approach offers complete dynamic control over the resonance bandwidth and opens applications in frequency conversion and light trapping.

New Scytinopteridae with elytrized tegmina are described: Ooscyta chertoprudi gen. et sp. n. from the Late Permian of Karaungir, East Kazakhstan and Synelytra tverdokhlebovorum gen. et sp. n. from the Early Triassic of Petropavlovka, Southern Cis-Urals, European Russia. Te fossil insect assemblages of Karaungir and Petropavlovka are briefy characterized. In the Late Olenekian of Petropavlovka, the earliest Ipsviciidae and Curvicubitidae are recorded, as well as the genera and possibly species characteristic of Madygen, which indicates that the Middle Triassic entomofauna began to form towards the end of the Early Triassic. Te evidence supporting the origin of true bugs from scytinopteroids is briefy discussed.

Tick-borne encephalitis is a flavivirus disease, endemic to vast areas of Europe and Asia, caused by the tick-borne encephalitis virus from the genus Orthoflavivirus, transmitted through the bite of a tick. The course of infection is characterized by fever followed by the development of potentially fatal encephalitis. Serological diagnosis of tick-borne encephalitis is complicated by severe cross-reactivity with antibodies to other endemic and imported flavivirus infections. The aim of the study was to obtain a recombinant analogue of domain III of the surface protein E of the tick-borne encephalitis virus (EDIII-TBEV) and assess its ability to detect antibodies to the tick-borne encephalitis virus and differentiate them from antibodies to other flavivirus infections. Materials and methods. A comparative study was performed using panels of sera containing and not containing antibodies to the tick-borne encephalitis virus, and panels of samples with antibodies to yellow fever, dengue, and Zika viruses. The study was conducted using commercial tests and experimental kits based on EDIII-TBEV in the ELISA format and in the dot analysis format. Results and discussion. It has been shown that the use of experimental kits based on EDIII-TBEV makes it possible to effectively detect IgG antibodies to tick-borne encephalitis virus and, in contrast to commercial tests, to differentiate them from antibodies to the pathogens of dengue, yellow and Zika tropical fevers. A recombinant analogue of domain III of the surface protein E in the tick-borne encephalitis virus can be a useful capture reagent when creating diagnostic test systems in the format of enzyme-linked immunosorbent assay and dot-immunoassay for the differentiated detection of IgG antibodies to the tick-borne encephalitis virus.

Background. Polysaccharides are known to possess adjuvant properties, they are biodegradable, safe, and are of low-labor production. In this regard, the development of polysaccharide-based adjuvants is an urgent task.The aim. To develop a method for obtaining mannans from the cell walls of Saccharomyces cerevisiae yeast and to study their adjuvant properties using subunit vaccine model.Materials and methods. The preparation of mannans was obtained from the Saccharomyces cerevisiae yeast by enzymatic and alkaline hydrolysis. Its adjuvant properties were assessed in BALB/c mice immunized with the recombinant receptor-binding domain (RBD) of the SARS-CoV-2 (S) protein (Delta (B.1.617.2)). The titers of specific antibodies in the blood sera were determined by ELISA assays using the recombinant RBD (Wuhan-Hu-1 and Delta), and the recombinant (S) protein (Wuhan-Hu-1, Delta and Omicron) as antigens. The titers of virus-neutralizing antibodies were determined using virus-neutralization tests with the SARS-CoV-2 virus strains Wuhan – hCoV19/Australia/VIC01/2020 (Wuhan-Hu-1), Delta – hCoV-19/Russia/PSK-2804/2021 (Delta (B.1.617.2)), and Omicron 1 – hCoV-19/Russia/Moscow171619-031221/2021 (Omicron (B.1.1.529)).Results. The developed scheme allowed for obtaining up to 200 mg of mannans from 10 g of yeast cell debris. Double, with a two-week interval, immunization with RBD (50 μg) in combination with mannans (40 μg and 10 μg) induced the production of specific antibodies in titers from 1:2477330 to 1:188360. The titer of virus-neutralizing antibodies to the Delta – hCoV-19/Russia/PSK-2804/2021 was 1:485 (40 μg of mannans per mouse).Conclusions. We developed a scheme for obtaining a low-toxic preparation of mannans from the Saccharomyces cerevisiae yeast. The highest adjuvant activity was achieved when using mannans at the dose of 40 µg per mouse. Blood sera obtained from the immunized animals neutralized both homologous and heterologous SARS-CoV-2 strains.

Background and Objectives: Progress in the development of pulsed radiation sources with high energy density makes it possible to study the nonlinear response of condensed matter to the disturbing influence of high-intensity electromagnetic fields. To understand the processes occurring in this case, adequate models are needed that qualitatively and quantitatively reproduce the characteristics of the materials under study. In this area, graphene is considered one of the most promising materials due to the specificity of its band structure. The purpose of the work is to present and test a new model based on the quantum kinetic equation, free from restrictions on such parameters as the frequency and strength of the electric field of the disturbing influence. Materials and Method: The approach used in the work is based on the quantum kinetic equation for the distribution function of charge carriers in the state space. It makes it possible, in the one-electron approximation, to nonperturbatively reproduce the ultrafast dynamics of carriers in an external classical electric field. The system under consideration is specified by the electron dispersion law. The approach was developed and implemented for the pseudo-relativistic approximation of massless fermions, successfully used in describing the features of graphene. However, by its definition, this approximation quite accurately reproduces the real dispersion law only in the low-energy region in the vicinity of the Dirac points. Therefore, the direct use of this version of the model to describe processes in which electronic states with high excitation energies are known to participate raises questions about the accuracy of the results obtained. The problem can be resolved by moving to an exact definition of the dispersion law through the parameters of the tight-binding model of nearest neighbors in the crystal lattice of the graphene. The presented work proposes an implementation option for such a procedure and verifies the results obtained. A generalization of the formalism for a two-level system with a massless Hamiltonian of general form is used, which universally defines the explicit form of the quantum kinetic equation and expressions for macroscopic observable parameters. Results: A computational model based on the exact tight-binding model Hamiltonian has been determined, which strictly takes into account the real law of graphene dispersion in reciprocal space. The new model has been verified. For this purpose, the results of its use are compared with the results of a similar model based on the massless fermion approximation. Under conditions of limiting the parameters of the perturbing influence, ensuring the generation of excited states with only low energies in the immediate vicinity of the Dirac points, an exact coincidence has been demonstrated both at the stage of determining the values of the distribution function and for the observed parameters. It has been shown that going beyond the applicability limits of the massless fermion approximation is accompanied by the appearance of qualitative and quantitative differences in the results obtained. Conclusion: The results of the work provide new opportunities for studying the behavior of graphene under extreme conditions of strong high-frequency fields, modeling and searching for new nonlinear effects, and accurately reproducing the ultrafast quantum dynamics of its electrons for states with high energy values.

The impact of the new coronavirus COVID-19 infection on the course of pregnancy, maternal and child health is largely unclear and controversial. The presented literature review analyzes changes in the immune, cardiovascular, and endocrine systems in women in physiological pregnancy. The peculiarities of the course of infection caused by SARS-CoV-2 virus in pregnancy, depending on the virus variant, are presented, the issues of infection pathways into immune and non-immune cells, including placental cells, as well as the issues of transplacental transfer of the virus – the key moment of infection of the embryo or fetus, on which the outcome of pregnancy also largely depends, are considered. Promising approaches to COVID-19 therapy are presented: use of inhibitors of transmembrane serine protease 2 (TMPRSS2), furin, angiotensin-converting enzyme (ACE2) and RNA-dependent RNA polymerase, amnion epithelial cells and their exosomes. At the same time, the potential use of mesenchymal stem cells in patients with severe COVID-19 pneumonia is reviewed. Difficulties and questions regarding the use of the above therapeutic methods in pregnant women are highlighted. Aspects of the use of surfactant preparations in newborns at risk of new coronavirus infection are considered.

Purpose: identification of opportunities and potential risks in the implementation of artificial intelligence technologies on the basis of the dominant trends analyzing in the current high-tech sector development of the global economy.Methods: the paper uses the system approach, the method of classification and systematization, the method of estimations and scientific abstractions, the methods of information analysis and synthesis, the method of data visualization.Results: the article considers economic and technical-technological aspects of building intelligent systems, establishes trends of their development in the direction of multitasking and autonomy of performed functions, identifies opportunities and threats arising from the development of this direction of scientific and technological progress. The study reveals the dual nature of further improvement of artificial intelligence systems, which offers broad prospects of application in various spheres of human activity, but can simultaneously generate risks due to the uncontrolled introduction of these technologies into the public space.Conclusions and Relevance:the development of intellectual technologies in the current period has a steady tendency towards increasing complexity of the tasks to be solved and increasing autonomy of artificial intelligence, provided by increasing its computational capabilities, which in a number of parameters (image classification, text content) exceed the capabilities of the human mind. At the same time, there is an aspiration of developers to gradually transfer to machines the key competences in the field of decision-making, which until now have remained in the exclusive competence of humans. This trend opens up broad prospects for the application of "smart" machines in public life, but at the same time generates a set of real and hypothetical risks, the dominant of which is the loss of human subjectivity in relation to the surrounding processes. The emerging dichotomy of technological development requires a serious rethinking of the existing approach to the creation and implementation of artificial intelligence systems in order to minimize the emergence of ethical risks and threats to human life.

To increase the effectiveness and immunogenicity of modern vaccines, especially subunit ones, it is required to use adjuvants. Polysaccharides, due to their safety and biocompatibility, are desirable candidates for the creation of vaccine adjuvants. The aim of our study was to develop a method for obtaining beta-Glucans from the yeast Saccharomyces cerevisiae cell wall, and evaluate their adjuvant properties. The high purity and non-toxicity of the resulting preparation was achieved by using enzyme complexes of cellulase and protease in combination with ultrasound (22 kHz) at the purification stage. The developed scheme allows for the yield of beta-Glucans up to 2 g from 100 g of the biomass of wet cells. The adjuvant properties of beta-Glucans were studied in 50 male BALB/c mice, weighing 16–18 g. Immunization was performed twice, with a 14-day interval, intramuscularly, 200 μl per animal. The recombinant receptor-binding domain (RBD) of the surface S protein of the SARS-CoV-2 virus (Wuhan-Hu-1 and B.1.617.2 (Delta)) was used as an antigen, at a dose of 50 μg per animal. A positive control group was administered with the antigen combined with aluminum hydroxide. As a negative control, mice injected with the saline solution were used. The titers of specific antibodies in the blood sera were determined by ELISA assays. RBD (Wuhan-Hu-1 and Delta), and S protein (Wuhan-Hu-1, Delta and Omicron) were used as antigens. The titers of virus-neutralizing antibodies were measured in neutralization tests using SARS-CoV-2 virus strains Wuhan-Hu-1, Delta (B.1.617.2) and Omicron (B.1.1.529). The results of the study have shown that beta-Glucans have the ability to enhance the production of specific and virus-neutralizing antibodies in mice immunized with RBD. The titers of specific and virus neutralizing antibodies are comparable to their levels in the group immunized with RBD and Al(OH)₃. It has been found in the experiments in white outbred ICR mice that the preparation belongs to practically non-toxic substances. Therefore, it can be concluded that the use of beta-Glucans could become a preferable alternative to the conventional adjuvants based on aluminum salts, being biocompatible, biodegradable and non-toxic substances of low labor-intensive production.

Nanophotonic structures have shown promising routes to controlling and enhancing nonlinear optical processes at the nanoscale. However, most nonlinear nanostructures require a handling substrate, reducing their application scope. Due to the underwhelming heat dissipation, it has been a challenge to evaluate the nonlinear optical properties of free-standing nanostructures. Here, we overcome this challenge by performing shot-controlled fifth harmonic generation (FHG) measurements on a SiC meta-membrane – a free-standing transmission metasurface with pronounced optical resonances in the mid-infrared (λ res ≈ 4,000 nm). Back focal plane imaging of the FHG diffraction orders and rigorous finite-difference time-domain simulations reveal at least two orders of magnitude enhancement of the FHG from the meta-membrane, compared to the unstructured SiC film of the same thickness. Single-shot measurements of the meta-membrane with varying resonance positions reveal an unusual spectral behavior that we explain with Kerr-driven intensity-dependent resonance dynamics. This work paves the way for novel substrate-less nanophotonic architectures.

Background. Cattle hypodermosis is a chronic parasitic disease (entomosis) that occurs as a result of parasitizing the larvae of warble flies in the body of animals. Disease is common in more than 55 countries of the world, causing great economic damage. It is considered as a parasitic disease with a certain zoonotic potential. Purpose. To conduct research on biological and ecological features of the warble flies that determines certain epidemiological traits of the caused pathology in Tavush Region of Armenia. Materials and methods. The observations were carried out in Tavush Region, and the experiments were carried out at the Research Center for Veterinary Medicine and Veterinary Sanitary Expertise at the Armenian National Agrarian University. The warble flies marked with stain, were released at a distance of 0.5 to 1.5 km from livestock farms with subsequent search and trapping of insects, located on pastures and on the skin of animals. Generally, 275 warble flies were released. Warble fly activity was evaluated visually counting the comparative number of flying insects at the fixed point per minute at different times of the day, as well as animal anxiety state caused by warble flies was identified. Statistical processing of experimental data was performed by means of “Vassart.net” online calculator. Results. Female warble flies Hypoderma bovis flew up to 12.1 km, while female warble flies H. lineatum did it up to 8.6 km. Females of H. bovis and H. lineatum demonstrated various spatial and circadian flying activity that depends on season, and altitude above the sea level. Spring generation of warble flies is more resistant to low air temperatures compared to the summer generation. Mild and humid summers, as well as an increase in the number of animals, contribute to an increase in the population of warble flies, while high temperature and high soil moisture contribute to the mass death of warble fly pupae developing in the ground. Conclusion. The research data cited in the article, detect the presence of a wide range of biocenotic factors that determine the epidemiology of cattle hypodermosis in the Tavush region of the Republic of Armenia. Cattle hypodermosis control plan was designed based on the results of the research, as well as natural and climatic conditions of Tavush region. Pasture prevention activities and periodic treatment of the cattle with insecticides were emphasized.