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The article presents data on the effects of cold stress on changes in the concentrations of endogenous ethanol (EE) and acetaldehyde (EA), and the activities of the key enzymes involved in their metabolism—alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (AHD) in laboratory animals. Mature male Wistar rats were used in the experiment. Animals in the vivarium were kept in cages at a temperature of 20%-22°C, without limitation of mobility, with free access to water with an adjustable light schedule (12 hours - light, 12 hours - darkness). Simulation of cold stressing was carried out for 7 weeks at a temperature of 1-2°C, starting from 0.5 hour to 6 hours per day by the fourth week of the experiment. The concentration of EE and EA was determined by gas chromatography-mass spectrometry (GC-MS). The analysis of the activity of the ADH and AHD enzymes was performed by standard spectrophotometric methods. The experiment showed that during cold stresses, the survival rate in rats strongly correlates with the EE content in the blood (r=0.757÷0.923). This fact suggests that when adapting cold-adapted animals to the effects of low temperatures, it is important to increase the EE concentration in the body, and the consumption of EE compensates for the increased need of the body in cold conditions for this metabolite. Based on the data obtained, a probable mechanism of the participation of EE in the processes of adaptation of higher vertebrates to cold is presented, which includes specific adaptive changes in the activities of the ADH and AHD enzymes.

Background: The fungus Candida albicans is one of the most common fungal human pathogens, causing numerous mucocutaneous infections. About 80% of the world population is colonized with this pathogen, and in many cases, it does not reveal its pathogenic properties. However in the events when the suppression of normal bacterial flora occurs, e.g. as a consequence of chemotherapy or antibiotics treatment, multi-resistant strains of Candida albicans can rapidly colonize the host organism and prevent the normal flora recovery, which in turn can trigger many other diseases especially in the case of immunocompromised patients. Methods: We used an integrated structural biology approach based on the single-particle cryo-EM reconstruction and macromolecule X-ray crystallography. Results: One of the most promising targets for antibiotic action is a protein synthesis apparatus and ribosomes in the cell. In this study, we characterized structurally the protein synthesis machinery of Candida albicans using the state-of-the-art techniques of single-particle Cryo-electron microscopy and macromolecular X-ray crystallography. Conclusion: We obtained the 2.4 Å resolution structure of the 80S ribosome from Candida albicans and the 4.2 Å resolution structure of the vacant C. albicans ribosome by X-ray crystallography. We believe that this study will shed light on mechanisms of antimicrobial resistance in C. albicans and improve candidiasis treatment in the future.

The purpose of the study is to analyze the effectiveness of the formation of culture-general competencies of economics students in the context of the blended learning environment. The following results have been obtained. A blended learning system to teach Econometrics has been introduced at two Russian universities and one Kazakh university. A questionnaire has been developed, and a sociological survey of economics students of the three universities has been conducted to assess the effectiveness of the formation of culture-general competencies in the context of blended learning of Econometrics. The analysis of the research results confirmed a number of hypotheses: H1 "Blended learning contributes to the formation of professional identity", H2 "Blended learning contributes to the formation of communication skills", H3 "Blended learning contributes to the formation of self-organization and self-education skills", H4 "Blended learning does not lead to a decrease in academic performance". The practical significance of the results obtained involves the fact that they make it possible to effectively implement blended learning technologies for the development of the competencies of economics students.