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Background: Our previous optical coherent tomography angiography (OCTA) study of rhegmatogenous retinal detachment (RRD) treatment has found an impaired retinal microvascular bed over a 12-month postoperative follow-up and warranted for the study of vitreous angiopoietin (Ang)-2 levels as a vascular destabilizing factor in patients treated for RRD. Purpose: To assess vitreous Ang-2 levels in patients with primary RRD and their association with OCTA-based changes in the macular microvascular bed in patients with RRD. Material and Methods: Eighty-seven patients with primary RRD were involved in the study and divided into two groups depending of the state of the macula: patients that underwent surgery for macular-on RRD (group 1) and those that underwent surgery for macular-off RRD (group 2). All patients had their vitreous samples taken and underwent subtotal posterior vitrectomy. Concentrations of Ang-2 in these samples were measured by an enzyme-linked immunosorbent assay (ELISA) kit (Human Angiopoietin-2 ELISA Kit, Thermo Fisher SCIENTIFIC, Rockford, IL, USA) in accordance with the manufacturer’s protocol. We assessed correlations of vitreous Ang-2 levels and OCTA-based parameters in patients. Results: At the preoperative vitreous Ang-2 level of 129.7 ± 51.99 pg/ml in group 1, there was a strong correlation of preoperative OCTA-based foveal avascular zone (FAZ) area, parafoveal deep capillary plexus density (PDCPD) and foveal deep capillary plexus density (FDCPD) with vitreous Ang-2 levels over the study period for group 1. At the preoperative vitreous Ang-2 level of 693.8 ± 634.7 pg/ml in group 2, there was a strong correlation of OCTA-based FAZ area, FDCPD, and PDCPD with vitreous Ang-2 levels at baseline and 12 months, and a moderate direct correlation of OCTA-based FAZ area, FDCPD, and PDCPD with vitreous Ang-2 levels at months 3 and 6. Conclusion: Vitreous Ang-2 levels were significantly lower in macula-on RRD eyes than in macula-off RRD eyes (129.7 ± 51.99 pg/ml versus 693.8 ± 634.7 pg/ml, p < 0.001). There was a strong direct correlation (p < 0.05) of Ang-2 with OCTA-based characteristics of the retinal microvascular bed (FAZ area, PDCPD and FDCPD) for both groups, which indirectly indicates the effect of the vascular destabilizing factor on the postoperative best-corrected visual acuity.

The global food crisis approach encourages finding new sources of replenishment of the phosphorus deficit in agriculture, making the unconventional sources of phosphorus particularly relevant. Despite numerous studies of phosphorus recovery methods, the need to increase the content of nutrients in the organo-mineral fertilizers obtained via anaerobic digestion of sewage activated sludge from municipal wastewater still exists. The greatest success in this area has been achieved by the biotechnologies which ensure the simultaneous production of biogas and biofertilizers. The present study proposes a sustainable technology for anaerobic digestion with the simultaneous capture of carbon dioxide and sodium carbonate production. It involves pre-comminution of the organo-mineral substrate (vegetal waste, activated sludge, phosphorus-containing component, and cheese whey) facilitating anaerobic digestion, and extraction of CO2 from biogas by absorption with a 10 % NaOH solution. Biomethanation reaction was found to have the first order with the activation energy of 24.8 kJ/mol, whereas the carbon dioxide absorption degree is proportional to the CO2 content in biogas. The results showed good potential for increasing the efficiency of both phosphorus recovery from municipal wastewater and anaerobic digestion to produce valuable products, including high-purity bio-methane (96 vol. % CH4), concentrated (∑NPKCa 53 %) organo-mineral fertilizer from digestate and soda ash. Obtained fertilizer increased potato yield by 35 wt. %. The study demonstrates a novel concept of carbon dioxide cycle looping in biogas production, as well as reducing greenhouse gas emissions by converting up to 98.7 % of CO2 into an additional marketable product – sodium carbonate, which contains 99 % Na2CO3.

An environmentally friendly method for phosphogypsum processing into N,Ca,S,P-fertilizers is proposed. Thus, was obtained a complex liquid N,Ca,S,P-fertilizer with the content of nutrients (% wt.) N:Ca:S:P = 56:26:12:6 in the dry product, and 16.8:3.6:7.8:1.8 in the liquid phase. The obtained fertilizer increased the yield of radish by 7.16% compared to the control. The advantage of the proposed method is reducing the cost of the fertilizer, increasing its nutritional value, and obtaining useful products from the waste.

Here we show the effect of the ionic liquid nature, its content and monomer/crosslinker ratio on the copolymerization of N-vinylpyrrolidone (NVP) with triethylene glycol dimethacrylate (TEGDMA) induced by UV or heat irradiation. For the first time, kinetics curves of photopolymerization NVP with TEGDMA in the presence of ionic liquids are obtained. The ionic liquids EmimBF4, BmimBF4, OmimBF4 and EmimTFSI with different cation and anion structures and lengths of the alkyl radical were varied in photopolymer compositions. To understand the influence of ionic liquids on the polymerization kinetics, photo-DSC, dynamic DSC, and FTIR were performed. Parameters obtained from photo-DSC curves allowed to develop the methodology for the stereolithography of ionogels. The presented data constitutes the complete dataset useful for 3D-printing of ionogels with high accuracy, which is reported in the main article.

The statistics of using downhole electric submersible pump (ESP) units in the oil fields of Eurasia show that hydroabrasive wear is a common cause of ESP emergency failures. The authors of this study theoretically and experimentally investigated the peculiarities of water–abrasive wear of ESP components. The research methodology and construction of the laboratory bench are described, and the results of experimental studies of determination of changes in the abrasivity index of impurity particles contained in the mixture pumped with the working stages of an ESP section are given. It is shown that large particles of mechanical impurities in contact with the metal of the working stages are subjected to intensive grinding of up to 0.25…0.3 mm; after that, particle size remains practically unchanged. An increased abrasiveness index of mechanical impurities causes an increase in the intensity of wear of interstage seals along the flow of a water–abrasive mixture (from the inlet to the outlet of the pumping section). Based on the obtained results, recommendations for selection of devices for formation-fluid cleaning during development and operation of oil wells are given. The relevance of work on improving the design of interstage seals of ESP units is substantiated.

The main principles of hydroabrasive wear of parts of the pumping stages of well’s electric submersible pumps are considered in this article. The concentration, grain-size distribution and shape of solid particles have the greatest impact on the abrasion ability of particles of mechanical impurities interacting with the parts of pumping equipment. The implementation of filters is the most effective and affordable way to protect borehole electric submersible pumps from hydroabrasive wear. Filters reduce the concentration and decrease the average grain-size of mechanical impurities going through the pumping stages. The authors propose variants of constructive and schematic solutions of self-cleaning slot filters, providing an increase in the operating time of electric centrifugal pump units during production of well fluid with a high content of mechanical impurities. The operating principle of the proposed filters is described. The results of calculations of deformation of tubing string during the increase in pressure at the oil wellhead are presented, confirming the possibility of restoring the permeability of spring filter elements without lifting the pump unit to the surface.