Розвиток критичного мислення учнів початкових класів на уроках математики

The article deals with the development of technology for the development of critical thinking in the process of teaching mathematics in primary school.У статті розглядається питання розроблення технології розвитку критичного мислення в процесі викладання математики в початковій школі

THE PERSPECTIVE OF N-CHLOROTAURINE INFLUENCE ON MULTI-DRUF RESISTANT MICROORGANISMS ASSOCIATED WITH DENTAL IMPLANTATION FAILURE

Introduction: Microorganisms colonizing the surface of dental implants can form biofilms that protect their microcolonies from mechanical impact, antimicrobial compounds, and immune factors. Prophylactic use of antibiotics during dental implantation can exert selective pressure on the development of antimicrobial resistance. In this context, N-chlorotaurine (NCT) is a promising compound to combat resistant agents. The aim is to investigate the efficacy of NCT against pathogens associated with dental implant complications. Materials and methods. A buffered 1% NCT solution adjusted to pH 7.1 was used for the study. Multidrug-resistant cultures (MDR) were identified. Determination of NCT activity was carried out by the agar and suspension method. The results. After standard antibiotic susceptibility testing, cultures classified as MDR were selected. 12 cultures were included in the MDR group, including seven S. aureus, three K. pneumoniae and three A. baumannii. MDR cultures of S. aureus had MRSA profile. Production of carbapenemases was confirmed in all MDR K. pneumoniae isolates, 2 of them showed production of metallo-β-lactamases. MDR isolates A. baumannii were also producers of metallo-β-lactamases. All 12 investigated MDR cultures were sensitive to NCT, the diameter of the zones of growth retardation was at least 15 mm. No significant difference was found between the effectiveness of 1% NCT solution against microorganisms with different mechanisms of drug resistance (t-test, p>0.05). When conducting studies in a liquid environment, a 1% NCT solution showed similar results, all MDR cultures were sensitive and showed a decrease in the microbial load (CFU/ml) by at least 2 log10 steps already 15 minutes after the start of the study. Notably, there was no significant difference in the efficacy of NCT against conditionally susceptible and MDR agents. Conclusions. Reducing the threat and burden of MDR pathogens is one of the goals announced by WHO and the Centres for Disease Control. Our study clearly confirms that various antibiotic resistance mechanisms do not affect the bactericidal activity of NCT, making it promising for the treatment of resistant infections

Economic Monitoring of Transformation Processes: National Realities and Foreign

The research is devoted to the theoretical and applied   organizational bases to held of the comparative analysis of the economic development of the regions of the Black Sea region. The main purpose of the article is the process of comparative analysis of economic development of the Black Sea region. The article tests the authors' hypothesis about the adequacy of the indicators defined for evaluation through the proposed number of relative indicators, which in the complex will characterize the achievements of the region in ensuring the economic stability of the regional system, quality of transformation processes and indirectly the conditions created by public authorities for economic development. There is confirmed the dependence of the use of the proposed methodological approaches and the constructed comparative profile of the regions of the region, which can be useful for identifying the strengths and weaknesses of the region, outlining key issues and developing regional development plans and programs. It is determined that the largest vector length in the Mykolaivska region, which indicates that in the region on a number of economic indicators achieved higher results than in other regions of the Black Sea region and on average in other regions of Ukraine during the study period

Comparative Analysis of Exo- and Endonuclease Activities of APE1-like Enzymes

Apurinic/apyrimidinic (AP)-endonucleases are multifunctional enzymes that are required for cell viability. AP-endonucleases incise DNA 5′ to an AP-site; can recognize and process some damaged nucleosides; and possess 3′-phosphodiesterase, 3′-phosphatase, and endoribonuclease activities. To elucidate the mechanism of substrate cleavage in detail, we analyzed the effect of mono- and divalent metal ions on the exo- and endonuclease activities of four homologous APE1-like endonucleases (from an insect (Rrp1), amphibian (xAPE1), fish (zAPE1), and from humans (hAPE1)). It was found that the enzymes had similar patterns of dependence on metal ions’ concentrations in terms of AP-endonuclease activity, suggesting that the main biological function (AP-site cleavage) was highly conserved among evolutionarily distant species. The efficiency of the 3′-5′ exonuclease activity was the highest in hAPE1 among these enzymes. In contrast, the endoribonuclease activity of the enzymes could be ranked as hAPE1 ≈ zAPE1 ≤ xAPE1 ≤ Rrp1. Taken together, the results revealed that the tested enzymes differed significantly in their capacity for substrate cleavage, even though the most important catalytic and substrate-binding amino acid residues were conserved. It can be concluded that substrate specificity and cleavage efficiency were controlled by factors external to the catalytic site, e.g., the N-terminal domain of these enzymes

Structural basis for selectivity and diversity in angiotensin II receptors

The angiotensin II receptors AT1R and AT2R serve as key components of the renin–angiotensin–aldosterone system. AT1R has a central role in the regulation of blood pressure, but the function of AT2R is unclear and it has a variety of reported effects. To identify the mechanisms that underlie the differences in function and ligand selectivity between these receptors, here we report crystal structures of human AT2R bound to an AT2R-selective ligand and to an AT1R/AT2R dual ligand, capturing the receptor in an active-like conformation. Unexpectedly, helix VIII was found in a non-canonical position, stabilizing the active-like state, but at the same time preventing the recruitment of G proteins or β-arrestins, in agreement with the lack of signalling responses in standard cellular assays. Structure–activity relationship, docking and mutagenesis studies revealed the crucial interactions for ligand binding and selectivity. Our results thus provide insights into the structural basis of the distinct functions of the angiotensin receptors, and may guide the design of newselective ligands