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The adhesion of Staphylococcus aureus ATCC® 25923 and the clinical strains of S.aureus, S.epidermidis on monofilament surgical mesh implants - macroporous polyester and microporous polypropylene in combination with biocides was assessed in an in vitro experiment. Staphylococcus cells adhered to the surface of implant fragments without treatment with biocides within a few hours, and there was no significant effect on the adhesion of the structure or chemical composition of the fiber. Short-term exposure of implants to the solutions of amoxiclav (100 μg/ml) and chlorhexidine (0.5%) led to inhibition of bacterial growth and contamination of the surface for at least two days. In the experiment with vancomycin (100 μg/ml), bacterial cells adhered on the surface of the mesh fragments after 24 h, but their amount was significantly lower than in the control group. It was noted that both implants in combination with chlorhexidine were not contaminated with S.aureus bacteria for 2 days under conditions of a high concentration of cells in the suspension. Regulation of bacterial adhesion using biocidal solutions can be a simple and economical strategy to combat the development of infection in the field of surgical intervention.

The thermal regime of underground mines, shaped by air temperature, velocity, and relative humidity, is a crucial factor for production and the health and safety of miners. While many aspects of this thermal regime have been thoroughly studied in the literature, local heat sources from mechanized equipment, such as load–haul–dump machines, conveyors, and auxiliary fans, have received comparatively little attention despite their significant impact on the thermal environment in mining development areas and stopes. This paper presents findings from a comprehensive study of the microclimatic air parameters in several nickel–copper and potash mines. We focus specifically on variations in air temperature in areas where mining equipment is operational. The heat output from different types of equipment, including load–haul–dump units, cutter–loaders, drilling rigs, conveyors, and auxiliary fans, has been quantified. We established empirical relationships for heat emissions from these machines and conducted a comparative analysis of their heat outputs. The main advantage of these relationships is their simplicity and the minimal number of input parameters required, making them practical for use in the field.

Government support measures help companies overcome various restrictions impeding their growth and develop ment, which is of special relevance for small and medium-sized enterprises (SMEs). These measures, therefore, must reach the target companies and ensure efficient allocation of resources. The article reveals key characteristics of SMEs in Russia that increase the probability of them receiving government support. The research methodology is based on public interest theory, public choice theory and the concept of economic freedom. The research method is a two-step regression analysis, in which the binary choice model is first evaluated, and then the LASSO model is used to assess the impact of the textual content of the companies’ websites. The dataset of the study is represented by data on 2,176 Russian metallurgical enterprises for 2020–2023, of which 57% were receiving government support. The results of the first step of evaluation showed that the organization’s age and size meas ured by revenue were the key factors associated with the probability of receiving government support. At the second step, we found that the mention of certain goods or materials on the websites, the enterprise’s location and orientation towards foreign stakeholders were significantly related to the likelihood of getting state support. The study offers tools for analyzing the determi nants of government support for SMEs and highlights the importance of this analysis for more efficient allocation of government resources.

Digital simulation of mine fires and explosions is an important stage in the process of developing technical solutions and measures aimed at improving the safety of personnel involved in underground mining. Correct simulation results determine the effectiveness of decisions in the event of an actual emergency situation. In this regard, due attention should be paid to each stage of the simulation, and especially to the initial stage of model parameterization. This study formulates a general principle for determining the parameters of mine fire and explosion models, in order to assess their development using the AeroNetwork analytical package. Such parameters in the event of a fire are heat and gas (afterdamp) releases. In the event of an explosion, excessive pressure at the shock front in the explosion origin. It has been established that when simulating a fire, it is advisable to use equivalent heat and gas releases determined by the content of combustible components in the combustion origin. In the event of burning mining equipment, these parameters can be calculated on the basis of the technical characteristics of a machine. Furthermore, when simulating an unauthorized explosion of explosives, the excess pressure determined by the dimensionless length of the active combustion area is calculated taking into account the weight and specific heat of an explosive, as well as the geometric parameters of a mine working. When simulating an explosion of a methane-air mixture (firedamp), the excess pressure is calculated taking into account the gas content of rocks in terms of free combustible gases, the length of a blast cut, the size of the area of increased fracturing, and the lower explosive limit of methane. Based on the proposed principle of the parameterization of emergency models, as an example, a model of fire and explosion development in existing extended dead-end workings (more than 1000 m long) passing coaxially to each other at different heights was developed. The numerical simulation of different emergency situations in workings was carried out, taking into account performing mining in difficult mining conditions.

Determining the sources of hazardous and toxic substances released into mine air, their gas composition, as well as providing each such source of pollution with the required amount of fresh air are important issues in terms of ensuring normal healthy and safe working conditions for miners. This paper studies blasting as one of the most dangerous sources of mine air pollution. The study was carried out for a long dead-end exploration working, and a development (preparatory) working of a copper-nickel mine. In accordance with the federal rules and regulations (FNiP), a number of requirements, including monitoring of gas hazard at a face, is applied to blasting operations. The study examined the behavior of gas-air mixture in dead-end mine workings after blasting. The findings are based on the experimental data obtained in the conditions of two dead-end workings at an operating coppernickel mine. A technique for the experimental studies of gas release after blasting in a dead-end working was developed. The main technical characteristics of the instruments involved in the in-situ measurements are given. Time dependences of the concentrations of toxic gases after blasting at the blasted working mouth, at the return ventilation current, and near a booster were established. In order to assess the reliability of the data obtained, the volume of released carbon oxides was calculated based on the data of gas analyzers and chemical reactions of explosives decomposition during detonation, depending on the types and weights of the explosives. A model of gas-air mixture transfer was described, constructed, and calibrated allowing for longitudinal dispersion. The Voronin model was used to simulate the gradual removal of toxic gases from the working face and solving the problem of boundary conditions. Based on experimental data, the coefficients of longitudinal dispersion, ventilation efficiency, and volume concentration of the considered gas admixture in the mixing zone at initial time were determined for a long dead-end mine working. The constructed gas-dynamic model and longitudinal dispersion coefficients obtained as a result of the analysis enabled the time required for long dead-end mine workings ventilation to be analysed and estimated. Based on the model, the algorithm for calculating the velocity of spreading the combustion products in a mine ventilation network in emergency situations is being improved. The value of longitudinal dispersion coefficient for different operating conditions is also being refined. Based on the gas distribution simulation within the interval of 1,500 m from a working face, the time required for the ventilation of a dead-end mine working was determined.

One of the urgent problems of modern health care is the growing resistance of microorganisms to antibiotics, including carbapenems, which until recently were considered as the drugs of choice in the treatment of life-threatening infections. Enzymatic inactivation of antibiotics, including through the production of carbapenemase, is the main mechanism of resistance in Gram-negative bacteria. The treatment of these infections presents significant difficulties due to the extremely limited arsenal of effective drugs. Aztreonam is currently the first and only monocyclic beta-lactam antibiotic, monobactam, which is used in clinical practice for the treatment of infections caused by gram-negative bacteria. The data obtained in vitro and clinical observations are presented. These results justify the use of the drug in infections caused by a number of "problem" Gram-negative pathogens, including those resistant to carbapenems. Aztreonam has a high potential and should be used to treat patients with nosocomial infections – the focus of its use is Gram-negative bacteria-producers of metallo-beta-lactamases.

This article examines whether the online context affects tournament theory incentive mechanisms. It investigates the impact of prize structure on player performance in eSports under online and offline conditions. Using a quasi-experimental approach with data from the Counter-Strike Global Offensive eSports scene, the study finds that high prize distributions increase individual output in both settings, but the incentive effect is weaker in online events. [ABSTRACT FROM AUTHOR]

This paper focuses on the aspects of intersection between the COVID-19 pandemic, Google search queries, and cultural dimensions of countries. Google Trend indices of 138 countries were collected for the topic "coronavirus" and analyzed to identify the determinants of abnormal health search intensity. Registered cases of COVID-19 in a country did not predict search patterns, yet deaths registered within a country did increase health search intensity. Abnormal health search behaviours were best explained using Hofstede's cultural dimensions of power distance, masculinity, and long-term orientation. [ABSTRACT FROM AUTHOR]

The thermal regime of underground mines, shaped by air temperature, velocity, and relative humidity, is a crucial factor for production and the health and safety of miners. While many aspects of this thermal regime have been thoroughly studied in the literature, local heat sources from mechanized equipment, such as load–haul–dump machines, conveyors, and auxiliary fans, have received comparatively little attention despite their significant impact on the thermal environment in mining development areas and stopes. This paper presents findings from a comprehensive study of the microclimatic air parameters in several nickel–copper and potash mines. We focus specifically on variations in air temperature in areas where mining equipment is operational. The heat output from different types of equipment, including load–haul–dump units, cutter–loaders, drilling rigs, conveyors, and auxiliary fans, has been quantified. We established empirical relationships for heat emissions from these machines and conducted a comparative analysis of their heat outputs. The main advantage of these relationships is their simplicity and the minimal number of input parameters required, making them practical for use in the field. [ABSTRACT FROM AUTHOR]

In the cold period of the year, to ensure the required thermal regime in underground mine workings, the air supplied to the mine is heated using air handling systems. In future, the thermodynamic state of the prepared air flow when it is lowered along the mine shaft changes due to the influence of a number of factors. At the same time, the processes of heat and mass exchange between the incoming air and its environment are of particular interest. These processes directly depend on the initial parameters of the heated air, the downcast shaft depth and the presence of water flows into the mine shaft. Based on the obtained experimental data and theoretical studies, the analysis of the influence of various heat and mass transfer factors on the formation of microclimatic parameters of air in the downcast shafts of the Norilsk industrial district mines is carried out. It is shown that in the presence of external water flows from the flooded rocks behind the shaft lining, the microclimatic parameters of the air in the shaft are determined by the heat transfer from the incoming air flow to the underground water flowing down the downcast shaft lining. The research results made it possible to describe and explain the effect of lowering the air temperature entering the underground workings of deep mines

Research has suggested many ways in which professional football players can increase their penalty shooting success rate. We set up a field experiment testing these recommendations. We perform the experiment with one of the most successful youth academies in the world. All players are highly skilled, including prospective and current Brazilian youth national players. The players either decide themselves where to shoot or the coach tells them where to shoot. The coach does not reveal if the decision is based on a random allocation or his own choice. The algorithm randomly selects where players must shoot. The results from the experiment show that the best outcome is when players choose where they want to shoot. Coaches and random algorithm have a lower success rate, although following research‐based recommendations. The findings are important as they show that researchers should test their recommendations in the field as they do not necessarily translate into real‐life settings. [ABSTRACT FROM AUTHOR]

The relevance of the study is caused by the lack of regulatory documents for the control of the rock mass in the conditions of its artificial freezing, unified requirements for organization and monitoring of the frozen wall formation. The main aim of the work is to substantiate the optimal technological parameters of the thermal control of the frozen wall. Objects of the research are the rock mass under the conditions of artificial freezing and the freezing system. Methods: experimental study of the temperature dynamics of the frozen rocks, statistical processing and analysis of experimental data; simulation of thermodynamic processes occurring in artificially frozen rock mass. Results. The paper presents the experimental measurements of temperature distribution in control wells in artificially frozen rock mass. The artificial freezing is considered in relation to the problem of mine shaft sinking in flooded rocks. Processing and analysis of experimental data shown the influence of the artificial freezing on local sections of the rock mass. A study was made of the influence of the control well location on the accuracy of the solution of the inverse Stefan problem. It makes possible to adjust the thermophysical properties of the rock mass model and calculate the temperature field in the entire volume of the frozen rock mass. It was determined that the control well should be placed straight between the adjacent freezing wells. The analysis of the emergency failures of the freezing wells showed that the required number of control wells should be at least 30 % of the total number of freezing wells. Performed thermal monitoring allows the substantiation of optimal locations and number of control wells with the necessary spatial resolution of temperature measurements of rock mass in depth. According to the results of the work, a methodology for selecting technological parameters of the method of frozen wall thermal control were proposed.

In the course of the research, the scientific literature was analyzed in terms of historical aspects of audit development. The analysis of scientific papers shows that there is no unified approach to audit periodization; this situation has developed due to a combination of objective reasons: the theory underlying the research, the object of research, methods and objectives of the research. Our research was based on the study of historical aspects of business audit in the following order: the origins of audit as an institution of financial control; the formation and evolution of audit in Ukraine (as part of the Russian Empire and the Soviet Union); the emergence of audit and the development of audit in its modern sense; modern trends in audit in the world. During the study it was found that the modern state of audit as an independent financial control and as commercial activity is determined by the external environment of the following aspects: the specific socio-economic relations from the position of the subject of the audit as a tool for independent financial control, specific development management science from the position of introduction of auditing as a tool of the relationship between the management units, development of audit as consulting from a position of auditing as a business. The article investigates institutional support (a set of state, professional and public institutions whose main functions are the regulation of audit and auditing activities) of audit framework of Western European countries.

Objective. To evaluate effect of «Haemoblock»TM preparation on in vitro bacterial colonization. Materials and Methods. Activity of «Haemoblock»ТМ product on the growth and colonization of S. aureus АТСС 25923, S. epidermidis ATCC 28922, E. coli АТСС 25922, P. aeruginosa АТСС 27853 cells in the suspension and on the surface of monofilament macroporous polyester mesh was evaluated. Results. This product at concentration of 0.062% and above inhibited bacterial growth and reduced biofilm mass and bacterial cell viability. In addition, the short-term exposure of the mesh implant to the tested product resulted in inhibition of the abiotic surface contamination. Conclusions. «Haemoblock»TM product allows not only to ensure hemostasis in open and laparoscopic surgery, but also to reduce the bacterial cell count in the surrounding tissues in the intra- and post-operative periods.