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The appearance of blood in the bowel movement is one of the most disturbing and serious symptoms of diseases of the gastrointestinal tract (GIT), especially its lower divisions whistleblower intestinal vascular integrity and mucous membranes. Invaluable in the diagnosis of bleeding from the lower GIT endoscopy is the colon, allowing to establish the source of bleeding in more than 90% of patients. The key to accurate diagnosis and successful treatment in the future is the optimal preparation of the patient for endoscopy. A number of foreign and domestic studies demonstrated high efficacy and safety of use in preparation for endoscopy / X-ray examination of the colon and for surgery on the colon preparation Fleet® Phospho-soda.

Aim. Acute pulmonary embolism (PE) is a common and often fatal disease with the level of mortality in the acute phase from 7 to 11%. In order to develop indications to thrombolytic therapy the short-term results of treatment with the use of combination therapy were studied. This treatment included: thrombolysis and /or anticoagulant therapy, with the usage of new oral anticoagulants and treatment of acute pulmonary hypertension. 231 patients with pulmonary embolism were examined. Methods and results. Angiography, echocardiography, multidetector computed tomography of the chest were used to evaluate the results of treatment. Among those groups prevailed elderly and senile patients with concomitant chronic disorders of the cardiovascular and respiratory systems. This for certain significantly worsens pulmonary embolism. Therefore, thrombolysis was used in cases of massive and submassive pulmonary embolism and as well as prostaglandin E1 drugs were used for the treatment of acute pulmonary hypertension and new oral anticoagulants. It was found that this treatment regimen resulted to a significant clinical improvement, restoration of adequate pulmonary blood flow and pulmonary hypertension rate decrease.

At present time, the death rate from cardiovascular disease occupies leading position in the structure of total mortality worldwide. The opportunity to conduct non-invasive studies of the coronary arteries has appeared through the development and implementation of multislice computed tomography (MSCT) into medical practice, which carry 64 or more sections. Aim. The purpose of this research is the identification of diagnostic capabilities of 64-slice MSCT in the verification of the severity of coronary artery lesions in patients with proven coronary artery disease. Methods and results. The study has been conducted on a 64-slice CT scanner Optima 660 (GE, USA). The degree of stenosis and calcification of the coronary arteries and also central hemodynamics have been studied. The analysis of survey results of 65 patients with coronary heart disease (30.8% of patients had a history of myocardial infarction) has been carried out. The average age of patients in observation group was 60.2 ± 10.56 years. Male patients were dominated (75.4%). According to the 64-slice MSCT it has been found that coronary artery stenosis occurs ≥ 50% in 90.0% of patients with myocardial infarction, and in 32.5% of patients with symptomatic coronary artery disease. Conclusion. Therefore, MSCT has sufficient specificity in the diagnosis of occlusive and stenotic lesions of the coronary arteries, and can be used for screening patients with suspected coronary artery disease.

The application of pulsed electric field (PEF) in electrodialysis has been proven to be efficient for a number of effects: increasing mass transfer rate, mitigation of scaling and fouling, reducing water splitting. Recently, the improvement of the membrane permselectivity for specific counterions was discovered experimentally by the group of Laurent Bazinet (N. Lemay et al. J. Memb. Sci. 604, 117878 (2020)). To better understanding the effect of PEF in electrodialysis, simulations were performed using a non-stationary mathematical model based on the Nernst–Planck and Poisson equations. For the first time, it was not only the condition used when the current density is specified but also the condition when the voltage is set. A membrane and two adjacent diffusion layers are considered. It is shown that when applying the regime used by Lemay et al. (the same current density in conventional continuous current (CC) mode and during the pulses in PEF mode), there is a significant gain in specific permselectivity. It is explained by a reduction in the membrane concentration polarization in PEF mode. In the CC mode of electrodialysis, increasing current density leads to a loss in specific permselectivity: concentration profiles in the diffusion layers and membrane are formed in such a way that ion diffusion reduces the migration flux of the preferentially transferred ion and increases that of the poorly transferred ion. In PEF mode, the concentration profiles are partially restored during the pauses when the current is zero. However, if a different condition is used than the condition applied by Lemay et al., that is, when the same average current density is applied in both the PEF and CC modes, there is no gain in specific permeability. It is shown that within the framework of the applied mathematical model, the specific selectivity depends only on the average current density and does not depend on the mode of its application (CC or PEF mode).

The broad possibilities of electrochemical impedance spectroscopy for assessing the capacitance of interphase boundaries; the resistance and thickness of the foulant layer were shown by the example of AMX-Sb membrane contacted with red wine from one side and 0.02 M sodium chloride solution from the other side. This enabled us to determine to what extent foulants affect the electrical resistance of ion-exchange membranes, the ohmic resistance and the thickness of diffusion layers, the intensity of water splitting, and the electroconvection in under- and over-limiting current modes. It was established that short-term (10 h) contact of the AMX-Sb membrane with wine reduces the water-splitting due to the screening of fixed groups on the membrane surface by wine components. On the contrary, biofouling, which develops upon a longer membrane operation, enhances water splitting, due to the formation of a bipolar structure on the AMX-Sb surface. This bipolar structure is composed of a positively charged surface of anion-exchange membrane and negatively charged outer membranes of microorganisms. Using optical microscopy and microbiological analysis, it was found that more intense biofouling is observed on the AMX-Sb surface, that has not been in contacted with wine.

The aim of the investigation is to show the possibility of updating of the training program of the discipline «Chemistry» intended for training of engineers of chemical specialties of higher educational institutions on the basis of results of the last researches in the field of nanochemistry. The article is addressed to the scientists and teachers developing the specific fields of science, to students and graduate students who have decided to devote themselves to new perspective science of the 21st century.Methods. The analysis of the works concerning the combinational scattering method (Raman spectroscopy) is made. Exposure to the combinational scattering method and the method of infrared spectroscopy is necessary for the undergraduates who are engaged in synthesis of new nanomaterials on the basis of carbon while deciding of the obtained experimental data. The physical and chemical analysis was used in the research to study the properties and structure of shungite of the Zazhoginsky field – the unique natural mineral containing nanoparticles and the effective sorbent applied to purification of drinking water (emission spectral analysis with inductively coupled plasma, Raman spectroscopy and Infrared spectroscopy).Results and scientific novelty. When processing shungite with toluene, ochroleucous resinous substance was educed; this is an organic substance according to data of IR-spectroscopy. On the basis of the analysis of data of Ramanspectroscopy, the line about 2700 cm–1 is offered to consider as the indicator of crystallinity. A variety of physical and chemical and structural properties in connection on the basis of shungite allows us to speak about chemistry of fullerenes and nanochemistry as the new perspective direction of chemistry.Practical significance. Described data on Raman-spectroscopy will help undergraduates, young scientists and researchers to identify various modifications of carbon in the nanomaterials synthesized by them on the basis of carbon. The data received during the research can be used for laboratory work «Determination of shungit nanocomponents through modern physical and chemical methods», having included it in the subject «Carbon» of the program of discipline «Chemistry». The materials of the article can also serve as a starting point for creation of a special short-term course on studying of materials of group of carbon in the system of advanced training for employees of the entities who are engaged in shungite processing.

Abstract. The aim of the investigation is to select how the thermal decomposition of crystallohydrate magnesium nitrates to capture the nitrogen compounds that are harmful to the environment; for the return of nitric acid to the initial stage of the process. Methods. The methods involve physical and chemical analysis (IR spectroscopy, rentgennofazovy analysis), thermolysis and thermal hydrolysis of magnesium nitrate. Results. Magnitudes of thermal effects are determined; mechanisms of thermal decomposition of magnesium nitrate in air and overheated water vapor are posed. Thermohydrolysis renders possible to produce undiluted magnesium oxide and regenerate nitric acid. Scientific novelty. Undiluted magnesium oxide was produced by the method that requires less energy consumption. Practical significance. The research results on regeneration of nitric acid and its reuse in the raw material processing containing magnesium open new prospects for production and can be applied as course materials for a practical training in organic chemistry in postgraduate study on chemical specialties.