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The nature of carbon, initial components, molecules of homochiral abiogenic synthesis and their preservation from decay and racemization for more than 4.5 billion years in carbonaceous chondrites has not been established. In the oxygen-free atmospheres of the nebula and early Earth, hydrogen and hydrogen-containing gases were oxidized with carbon monoxide and carbon dioxide to form carbon and water, as well as the intermediates of these reactions, formaldehyde and methane acid. Together with ammonia, they were the initial components of organic synthesis. According to the Rebinder rule, carbon adsorbs hydrogen well, including in organic molecules. In this connection, experiments with the assumed conditions of the early Earth were carried out by adsorption on carbon to obtain R-(rectus, Latin) ribose from formaldehyde, and S-(sinister) serine from formaldehyde, methane acid and ammonia. For other S-amino acids, a stereo chemical justification of their formation based on S-serine is given. For carbonaceous chondrites, the results of the above experiments were confirmed by the correlation of an increase in homochiral excess with an increase in the amount of hydrogen in aldonic acids and lactic acid with a coefficient of 0.94 and 0.85 in amino acids. The justification of the homochiral process will reduce the costs of searching for life on planets, for scientific research, for the production of medicines, perfumes, food, and so on. Doubts about the extraterrestrial origin of homochiral enantiomers in carbonaceous chondrites arise most often due to a lack of understanding of the reasons for their appearance. This work will significantly reduce such skepticism.

The aim of this literature review was to demonstrate the pluses and minuses of each kind of biopsy, which can be helpful for preparing an algorithm and determining the indications and contraindications for each prostate biopsy (PB). Prostate biopsy is the main method of diagnosing prostate cancer (PC), and it remains relevant even in spite of the appearance of a number of new diagnostic tests and methods. Transrectal 12-core biopsy without pre-biopsy mpMRI remains a routine sampling of prostate material. But with the appearance of a great variety of PB and their introduction into practice, there arises the need to compare these methods with each other. At present, all available studies dealing with the informativity of some biopsy method or another, were conducted in different time periods and cannot reliably reflect their informativity for making a comparison. In our opinion, further research into this problem is required and research works should study the informativity of various kinds of biopsy depending on visualization of a pathological site for suspected prostate cancer, in TRUS and its location coincidence in mpMRI, in Pi-RADSv2.1 classification. Key words: prostate biopsy, prostate cancer, transrectal ultrasound

To study the survival rate of patients without biochemical recurrence according to the Stuttgart and Phoenix criteria in terms of their correlation with four different PSA nadir values as predictors of clinical recurrence in patients with localized prostate cancer who underwent total HIFU prostate ablation.The object of the study was patients with morphologically proven localized RP by biopsy results, who were treated with prostate cancer by HIFU ablation on the Ablatherm Integrated Imaging apparatus (EDAP TMS, France). The study included 658 patients in whom HIFU ablation was used as primary treatment of localized prostate cancer (stages T1 - T2) without previous use of other methods (hormonal, radiation therapy) For the analysis, a continuous sample of patients was selected, which were divided into four groups depending on the PSA nadir level: less or equal 0.2 ng / ml (1 group), 0.21-0.5 ng / ml (group 2), 0.51-1 ng / ml (group 3) and1 ng / ml (group 4). sensitivity, specificity, predictive value, and 5-year biochemical relapse-free survival according to the Stuttgart definition and the Phoenix definition in the PSA nadir groups.The median (range) of the observation period for the patients was 5.3 (3-7) years, the mean time to reaching PSA nadir was 14.5+/-2.6 weeks. PSA nadirs less or equal 0.2, 0.21-0.5, 0.51-1.0 and1 ng/ml were achieved in 231 (35.1%), 132 (20.0%), 105 (15, 9%) and 190 (28.8%) patients, respectively. Survival without biochemical relapse in accordance with the Stuttgart definition in the four groups allocated for the PSA nadir was 82, 65, 43 and 32%, respectively (p0.001), according to the Phoenix definition - 94, 74, 66 and 47% (p0.001) respectively. According to the results of the control biopsy, 601 (91.3%) patients in the 1st and 2nd groups had a negative oncological status (approximately 85%).This study confirms that PSA nadir after HIFU ablation predicts biochemical recurrence-free survival and is a reliable marker that is easy to integrate into routine clinical practice.

The topic of renal cystic lesions is described in the article. The localization and structure of solitary, parapelvic and multiple sinus cysts are discussed. The Bosniak classification (1986) is presented, as well as the updated Bosniak classification, in which a number of modifications in 2019 were made. The contemporary diagnostic methods are mentioned, as well as factors that allow to select patient for active surveillance. Current surgical procedures are presented.

The presented nonisothermal technique for investigation of membrane gas separation (using MDK-1 membrane as an example) demonstrates possibilities of rapid assessment of the separation power of commercial membranes for both individual components and various mixtures in the temperature range of‒20 to +40°C. The efficiency of the membrane process under these conditions (cross-flow membrane module model) for separation of propane–methane mixtures has been evaluated. It has been shown that the permeability of methane decreases with a decrease in temperature in the Arrhenius coordinates and the propane permeability increases. The separation selectivity in the mixture decreases by more than twofold in comparison with the ideal selectivity. Nevertheless, a significant improvement of separation has been observed at lower temperatures, with the recovery of the desired product and its purity being variable in a wide range depending on the practical goal. The nonisothermal technique is supposed to be useful for rapid selection of conditions (temperature, pressure, components to be separated) for efficient application of polymeric membranes for separation of hydrocarbon-containing mixtures that are close in composition to real gas sources.

The features of the carbon dioxide reforming of ethanol and an ethanol-glycerol mixture to synthesis gas in the presence of porous membrane catalyst systems have been studied. It has been shown that the CO2 reforming of alcohols in open pores of ceramic membranes modified with nanosized active palladiumcontaining components proceeds at a higher rate as compared to that in a conventional fixed-bed flow reactor charged with a catalyst of similar composition.

A particular role in the harmonious exploitation of raw materials is assigned to organic sources of fuels based on renewable biomass. The most promising feedstocks of major energy sources, such as hydrogen and organic components of motor fuels, include ethanol and other bioalcohols, i.e., the primary products of its conversion. In this work, we describe the results for new reactions of conversion of ethanol and a mixture of ethanol and glycerol, which are the major products of biomass, to the C3–C10 alkane-olefin fraction in the presence of nanoscale mono- and bimetal-containing active components supported on γ-Al2O3 (〈d〉 = 5–8 nm) and on the inner surface of microchannels of ceramic membranes (〈d〉 = 15–20 nm). Mono- and bimetallic alkoxide and acetate complexes are used as precursors. It is found that the selectivity for the ethanol conversion to aliphatic hydrocarbons, as well as the content of branched structures, heavily depends on the nuclearity and composition of metal-complex precursors supported on γ-Al2O3. It is found for the first time that glycerol exhibits high reactionary ability in the reaction of cross-condensation of the carbon skeleton of alcohols of different nature. In the presence of a Ta-Re-containing system, a mixture of ethanol and glycerol is converted to 60% of C4–C10+ olefins, which contain up to 50% of branched structures. It is shown that by varying the composition of Pd-Zn-containing active components, it is possible to targetedly convert ethanol to the olefin, alkane, or alkane-olefin fraction. Porous membrane-catalyst systems are designed to produce hydrogen and syngas from biomass products; the systems exhibit high activity in the carbon dioxide and steam reforming of ethanol, a mixture of ethanol and glycerol, and acetic acid. A scheme for the production of a wide range of valuable organic products based on bioalcohols containing no toxic impurities and independent of crude oil is described. According to this scheme, alkanes derived from ethanol and other bioalcohols are the major components of motor fuels; a large number of organic synthesis products can be derived from olefins, hydrogen, and carbon monoxide in the carbonylation/hydrocarbonylation processes.

This work is devoted to a structural study of a highly dispersed Pd nanosystem, which is stabilized in the TiO2 matrix, by XAFS spectroscopy. Nanocomposite was prepared from bimetallic PdCo(μ-OOCMe)4(NCMe) precursor followed by processing in several ways: calcination in air and in argon and microwave irradiation. The local structure of Pd catalysts formed by different methods was studied. Possible structural models were considered in detail.

OBJECTIVE To study the survival rate of patients without biochemical recurrence according to the Stuttgart and Phoenix criteria in terms of their correlation with four different PSA nadir values as predictors of clinical recurrence in patients with localized prostate cancer who underwent total HIFU prostate ablation. MATERIAL AND METHODS The object of the study was patients with morphologically proven localized RP by biopsy results, who were treated with prostate cancer by HIFU ablation on the Ablatherm Integrated Imaging apparatus (EDAP TMS, France). The study included 658 patients in whom HIFU ablation was used as primary treatment of localized prostate cancer (stages T1 - T2) without previous use of other methods (hormonal, radiation therapy) For the analysis, a continuous sample of patients was selected, which were divided into four groups depending on the PSA nadir level: less or equal 0.2 ng / ml (1 group), 0.21-0.5 ng / ml (group 2), 0.51-1 ng / ml (group 3) and> 1 ng / ml (group 4). sensitivity, specificity, predictive value, and 5-year biochemical relapse-free survival according to the Stuttgart definition and the Phoenix definition in the PSA nadir groups. RESULTS The median (range) of the observation period for the patients was 5.3 (3-7) years, the mean time to reaching PSA nadir was 14.5+/-2.6 weeks. PSA nadirs less or equal 0.2, 0.21-0.5, 0.51-1.0 and > 1 ng/ml were achieved in 231 (35.1%), 132 (20.0%), 105 (15, 9%) and 190 (28.8%) patients, respectively. Survival without biochemical relapse in accordance with the Stuttgart definition in the four groups allocated for the PSA nadir was 82, 65, 43 and 32%, respectively (p