312 research outputs found
Hydrothermal synthesis of zeolites from coal fly ash
The fly ash, from the combustion of coal to produce energy and heat, is an industrial waste, in which large accumulations represent a serious environmental threat. To reduce the environmental burden and improve the economic benefits of energy production, the science and industry focus on the transformation of coal combustion byproducts into new functional materials. The fly ash was studied by modern analytical methods. As a result of the hydrothermal reaction, several types of zeolites were synthesised from the fly ash: analcime, faujasite (zeolite X) and gismondine (zeolite P). It was shown that the experimental conditions (temperature, reaction time and alkali concentration) have a significant influence on the type of zeolite and its content in the reaction products. The series of experiments resulted in building approximate crystallisation field of zeolites and other phases as the first stage of the formation of ceramic membrane and other materials
Nanoindentation of human donor cornea for detecting the effectiveness of laser-induced collagen crosslinking
Regional climate modeling activities in relation to the CLAVIER project
Observational records show that the global climate is changing and these changes are visible in the Central and Eastern European Countries (CEEC). Certainly negative impacts of climate change will involve significant economic losses in several regions of Europe, while others may bring health or welfare problems somewhere else. Within the EU funded project CLAVIER (Climate ChAnge and Variability: Impact on Central and Eastern EURope) three representative CEEC are Studied in detail: Hungary, Romania, and Bulgaria. Researchers from 6 countries and different disciplines identify linkages between climate change and its impact on weather patterns with consequences oil air Pollution, extreme events, and water resources. Furthermore, an evaluation of the economic impact on agriculture, tourism, energy supply, and public sector will be conducted, CLAVIER focuses oil ongoing and future climate changes in CEEC using measurements and existing regional scenarios to determine possible developments of the climate and to address related uncertainties. Three regional climate models are used to simulate the climate evolution in CEEC for the period 1951 to 2050, the future regional climate projection being the first half of the 21st century. The issue of climate change uncertainties is addressed through the multi-model and multi-scenario ensemble approach. As a result, CLAVIER establishes a large data base, tools, and methodologies, which contribute to reasonable planning for a successful development of society and economy in CEEC under climate change conditions. Current regional climate projections show a strong warming and drying during the summer months, which seems partly due to a systematic error in model simulations. Detailed validation of the CLAVIER simulations, which goes much beyond this paper, is needed, and the results have to be related to possible climate changes projected for the region in future simulations
The effect of the laser-induced structures’ surface morphology on the luminescence of thermostable polybenzimidazoles
This study was performed in the framework of the RFBR grant Mol_а 18-33-00645
Metallurgists of the Mining university and development of monetary industry. 245 years of history
Monetary industry combines several stages of metallurgical processes, which are continuously improved with the development of technology and the level of knowledge in the field of non-ferrous metals. The graduates of the Mining Institute, metallurgists of several generations, took part in establishment the Mint and development of technology to produce coins. Since January 24, 1718, when Peter the Great signed the decree «on production of small and large coins ...», the history of the monetary system of Russia and the coining of the first silver rubles began, which subsequently formed the basis of money relations. Twenty-four graduates of the mining and metallurgical departments of the Mining University worked as heads and münzmeister of the Mint. Silver rubles and work of Russian münzmeisters provided financial stability in Tsarist Russia from 1718 to 1917 and laid the foundation for further development of the monetary industry, taking into account new knowledge in the field of enrichment, preparation of polymetallic ores and their melting, and also stamping and processing of precious metals. This is the history of Russia and St. Petersburg, it combined the history of the Mining University, which this year will be 245 years old. It is of scientific interest to restore historical justice and update the methodological knowledge in the field of technology of monetary industry and metallurgical processes
Genetic diversity of hepatitis C virus in Nanaian region, Khabarovsk territory
Examining hepatitis C virus (HCV) genetic diversity is of great practical value in molecular-epidemiological research, development of specific prevention tools and outlining therapeutic strategy.Aim of study is to conduct analysis assessing HCV genetic diversity circulating in the Nanaisky Region population of the Khabarovsk Krai.Materials and methods. Molecular and genetic analysis of 124 blood plasma samples collected from patients with chronic hepatitis C and residing in the Nanaisky Region was conducted.Results. HCV RNA was detected in 84 (67.7±4.2%) plasma samples. HCV genotyping was performed by using AmpliSens — 1/2/3 kit (Central Research Institute of Epidemiology, Moscow, Russian Federation) showing that genotype 3 dominated reaching up to 47.6±5.4% (n = 40). Genotype 1 was detected in 30 patients (35.7±5.2%). In thirteen cases (15.5±3.9%) genotype 2 was identified, whereas in one case (1.2±1.2%) virus genotype was unidentified. Phylogenetic analysis of the nucleotide sequences in HCV NS5B region was performed for 60 HCV RNA-positive samples showing subtype ratio as follows: 1a — 2 (3.3±2.3%), 1b — 23 (38.3±6.3%), 2а — 6 (10.0±3.9%), 2с — 2 (3.3±2.3%), 3а — 27 (45.0±6.4%). Three samples of RF2k/1b recombinant virus were found. A full NS2 gene nucleotide sequence was cloned in order to confirm the recombination event. The results of the study evidence about a need to conduct multi-layered examination of patients with chronic hepatitis C by using current molecular and biologic methods for assigning proper therapy coupled to characteristics of the isolated strains. The data regarding hepatitis C virus molecular and genetic parameters circulating in the Far Eastern Federal District, Russia, are rather limited. Hence, our study would contribute to current understanding of HCV genovariants circulating in territories of the Russian Federation
Apolipoprotein A-I increases the activity of lysosomal glycosidases in the liver of mice with BCG-induced tuberculosis inflammation
This work shows the ability of apolipoprotein A-I to influence the activity of lysosomal glycosidases in the liver of mice in a model of BCG-induced tuberculous inflammation. The aim of the investigation was to study the activity of lysosomal glycosidases in the liver of mice using a model of BCG-induced tuberculous inflammation after intravenous administration of apolipoprotein A-I. Material and methods. The studies were performed on male CBA mice weighing 20-22 g. Disseminated tuberculous inflammation was modeled by a single intraperitoneal injection of 0.5 mg of BCG vaccine. The activity of lysosomal glycosidases was assessed spectrofluorimetrically by the content of hydrolysis products of the corresponding fluorogenic substrates. Results. Tuberculous inflammation led to a pronounced decrease in the activity of lysosomal glycosidases in the liver. Thus, β-galactosidase was decreased 2.3 times, β-glucosidase – 2.8 times, β-glucuronidase – 2.5 times compared with healthy animals. Intravenous injection of apolipoprotein A-I to animals against the background of BCG infection prevented a significant decrease in the enzymatic activity of glycosidases and these values practically did not differ from the control values. Conclusions. Enzymatic activity of lysosomal glycosidases in the group of mice with intravenous administration of apolipoprotein A-I against the background of BCG infection was 1.5–2 times higher than the corresponding indicators in the group of animals with BCG-infection without administration of apolipoprotein A-I, i.e. without treatment
Infective endocarditis and COVID-19: the impact of SARS-CoV-2 infection on diagnostics, course, and prognosis
Aim. To study the impact of coronavirus disease 2019 (COVID-19) pandemic on hospitalization rates, diagnosis, and outcomes of infective endocarditis (IE) with a subanalysis of IE course in combination with COVID-19.Material and methods. This prospective cohort study included 168 patients with definite or probable IE (DUKE 2015) hospitalized in the V.V. Vinogradov City Clinical Hospital from July 2017 to July 2022. All patients underwent a conventional examination in accordance with current clinical guidelines. We studied clinical, paraclinical and etiological parameters, as well as outcomes.Two clinical observations of the combination of IE and COVID-19 are presented.Results. When assessing the local registry of patients with IE, a trend towards an increase in hospitalizations rate of IE in 2021-2022 was shown, with a decrease during the period of long-term lockdowns in Moscow and a subsequent surge after their cancellation. Patients with IE during the COVID-19 pandemic had a more favorable clinical profile, a 2-fold increase in IE diagnosis (due to late hospitalization), frequent detection of Staphylococcus aureus MSSA (32,6%), and frequent surgical treatment (up to 87,6% with a combination of IE and COVID-19), as well as high in-hospital mortality, but without a tendency to increase (30,4%). Clinical observations of IE and COVID-19 combination are presented, which demonstrates the contribution of COVID-19 as the only risk factor for native tricuspid valve IE in a patient without predisposing causes, as well as a factor in the unfavorable prognosis for native aortic valve IE after the addition of COVID-19, which led to lethal outcome.Conclusion. The present study demonstrates the profile of patients with IE and COVID-19 depending on the epidemiological situation of COVID-19 and the association with SARS-CoV-2 infection. The data obtained make it possible to discuss the potential relationship between COVID-19 and IE. The "endocarditis team" determines the timely implementation of surgery and the absence of an increase in inhospital mortality, regardless of the epidemiological situation
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