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The rapid rate of acquisition and spread of resistance to antibiotics by microorganisms leads to the search and investigation of new ways of combating infectious agents. Being a modern, minimally invasive method with an almost complete absence of side effects, the use of low-intensity laser radiation can be considered as one of the alternatives to traditional antibiotic therapy. At the same time, the search for new chemical compounds with pronounced antimicrobial activity is also promising. The impact of low-intensity laser of the red spectrum (λ = 660 nm) on the sensitivity of a clinical isolate of Staphylococcus aureus to newly synthesized halogen- and chalcogen-halogen-containing derivatives of the quinazoline and benzothiazole series was studied using the serial microdilutions method with the determination of minimal inhibitory and minimal bactericidal concentrations. To evaluate the antimicrobial properties of the investigated substances in dynamic, we investigated their activity two months after the synthesis with subsequent comparison to freshly synthesized compounds. The research results indicate that the most pronounced antimicrobial effect was shown by trichlorotelluromethylthiazoloquinazolinium chloride and propargylthiobenzothiazolium hexachlorotellurate. Evaluating the dynamics of the activity of the studied compounds, it was noted that the absolute majority of substances retained their properties, which indicates their stability. When evaluating the effect of irradiation of microbial inoculum with low-intensity laser radiation on the susceptibility to chemical compounds, an increase in the sensitivity of irradiated microorganisms to some investigated chemicals was noted compared to similar non-irradiated microbial suspensions. In the case of 2 out of 9 studied chemical compounds we noted a 2- to 4-fold decrease in the minimal inhibitory concentration for irradiated microbial suspensions. A decrease in the minimal bactericidal concentration after irradiation was noted for one of the substances. In the cases of butynylthiobenzothiazolium hexabromotellurate, and tribromotelluromethylthiazoloquinazolinium bromide, decrease of both minimal inhibitory and minimal bactericidal concentrations in the irradiated inoculum was observed. The above shows that low-intensity laser radiation under certain parameters increases the susceptibility of microorganisms to antimicrobial agents.

Abstract The regulation of repair processes including base excision repair (BER) in the presence of DNA damage is implemented by a cellular signal: poly(ADP-ribosyl)ation (PARylation), which is catalysed by PARP1 and PARP2. Despite ample studies, it is far from clear how BER is regulated by PARPs and how the roles are distributed between the PARPs. Here, we investigated the effects of PARP1, PARP2 and PARylation on activities of the main BER enzymes (APE1, DNA polymerase β [Polβ] and DNA ligase IIIα [LigIIIα]) in combination with BER scaffold protein XRCC1 in the nucleosomal context. We constructed nucleosome core particles with midward- or outward-oriented damage. It was concluded that in most cases, the presence of PARP1 leads to the suppression of the activities of APE1, Polβ and to a lesser extent LigIIIα. PARylation by PARP1 attenuated this effect to various degrees depending on the enzyme. PARP2 had an influence predominantly on the last stage of BER: DNA sealing. Nonetheless, PARylation by PARP2 led to Polβ inhibition and to significant stimulation of LigIIIα activities in a NAD+-dependent manner. On the basis of the obtained and literature data, we suggest a hypothetical model of the contribution of PARP1 and PARP2 to BER.

Introduction. In-line analysis of ethanol content in gasoline blends is currently one of the urgent needs of fuel industry. Developing safe and secure approaches is critical for real applications. A phononic crystal sensor have been introduced as an innovative approach to high performance gasoline sensing. Distinguishing feature of proposed sensor is the absence of any electrical contact with analysed gasoline blend, which allows the use of sensors directly in pipelines without the risk of explosion in an emergency.Aim. Investigation of the possibilities of using phononic sensor structures to determine the ethanol content in liquid hydrocarbons.Materials and methods. A theoretical analysis of sensor structure was carried out on the basis of numerical simulation using COMSOL Multiphysics software. For measurement, substances of ordinary gasoline and gasoline 63–80 with ethanol concentrations in the range of 1–10 % by volume in increments of 2 % were prepared. The phononic crystal sensor was designed as a stainless steel plate with cylindrical holes and a resonant cavity, formed as a running across the wave propagation path slit between two lattices.Results. In-line analysis of measuring the concentration of ethanol in alcohol-containing fuels on a phononic crystal structure with a resonant cavity was carried out. Using the Agilent4395A admittance meter, the transmission spectra of longitudinal acoustic waves through the gasoline-filled sensor structure with were obtained. The non-linear correlation between the composition and the speed of sound of the blend is presented in the article is due to the ability to reduce the speed of sound of the mixture with an increase in ethanol concentration in the range of 0–10 % by volume.Conclusion. A measurement structure on the basis of phononic crystal was created. The measurements of various gasoline-ethanol mixtures show that the sensor has significant sensitivity (0.91 kHz/ms−1 ) with quality factor of 200) to distinguish between regular fuels, gasoline based blends and the presence of additives in standard fuels. The sensor has prospects for in-line analyzes the composition of liquid hydrocarbons.

Introduction: competitions occupy a large share in the future activities of modern bachelors in physical culture. To organize and conduct competitions at various levels, it is necessary to acquire additional competence - the ability to organize and conduct competitions, to judge the basic sports and the chosen sport. The relevance of the study lies in the need to develop a course that provides professional training for bachelors of pedagogical education (“Physical culture” profile) for organizing and conducting competitions at various levels.Materials and methods: we used the following research methods: theoretical - analysis, synthesis, modeling, comparison; empirical - questioning, observation and testing. We conducted a survey in order to identify the relevance of the developed author's course of additional professional training “Organizing and conducting sporting events” and introducing it into the system of continuous training for bachelors in physical culture.Results: in order to master students' competence related to the organization and holding of sporting events at various levels, an additional educational program “Organizing and conducting sporting events” was developed and implemented. The purpose of the developed course is the formation of additional professional competencies that ensure the ability and readiness of students to conduct various kinds of competitions; formation of the ability to use a variety of physical culture to maintain health.Discussion and Conclusions: the results of the study revealed the urgent need to expand the professional field of the future graduate in physical culture. A survey among the future bachelors in physical culture showed the need for the implementation of an additional course “Organization and holding of sport events”. To ensure the formation of additional professional competencies of graduates and future professionals in the field of competition to a new level, it is necessary to introduce into the educational process the author's course “Organization and holding of sport events”.