Some Environmental Problems of the Danube Delta

The Danube River originates in the mountain range Shvartsvold (Germany), the merger oftwo small mountain streams - Brigham and Breguet. On the way to the Black Sea (which lasts thisway for 2857 kilometers) in many tributaries of the Danube flows, the length of more than thirty ofthem exceeds 100 kilometers. Danube level difference between the top and bottom of its points is of678 meters. The catchment area of the Danube has vast agricultural areas, large industrial centers andtowns. At 23 miles above Ismail single channel of the Danube is divided into two branches: the leftandright Kiliya - Tulchinsky. Tulchinsky sleeve in turn is divided into two branches, or Girlie -Sulina and St. George. The most water-bearing Arm is Chilia. Through it passes about 75% of theflow

Prospects for the use of Arctic routes in the context of climate change and the implementation of the concept of sustainable development of the Arctic zone

The urgent need to solve environmental problems and meet the needs of people requires finding alternative ways to deliver goods in the most environmentally friendly and safe way. In addition, the climatic changes occurring on our planet open up additional prospects for the use of the Arctic for economic purposes, in particular, the use of the Northern Sea Route for cargo transportation. In the modern world economy, sea cargo transportation accounts for about 80% of all cargo transportation. The main cargo flow is carried out through the Southern Sea Route (SSR), along which goods are transported from Europe to Asia. For quite a long period of time, shipowners and logistics companies did not perceive the Arctic region as an alternative to traffic from Asia to Europe or North America, while navigation in the Arctic was much more than just transport shipping. At the same time, the situation has changed significantly in the 21stcentury. The interest in this region among the states of the Arctic zone, as well as other countries, is connected not only with the presence there of large reserves of mineral resources, solving geopolitical problems, but also the search for alternative sea routes for cargo transportation between Europe, North America and Asia. In connection with the blockade of the Suez Canal in March 2021, the question of the need to redirect cargo transportation to alternative routes – the Northern Sea Route (NSR), as part of the Northeast Passage, and the Northwest Passage became acute. The Suez Canal is the busiest and longest sea artery. In addition, this area is unsafe due to frequent attacks by pirates. Due to the geographical features of the SSR the presence of sufficiently narrow places along the route - under the condition of increasing traffic, does not contribute to the free passage of ships. Meanwhile, the active melting of the Arctic ice in the foreseeable future will allow navigation along Arctic routes at higher latitudes and without the escort of icebreaker transport. All of the above allows us to consider navigation in the Arctic latitudes as an actual alternative to the Southern Route, which will serve as the beginning of sustainable development of the Arctic region

Prospects for the use of Arctic routes in the context of climate change and the implementation of the concept of sustainable development of the Arctic zone

The urgent need to solve environmental problems and meet the needs of people requires finding alternative ways to deliver goods in the most environmentally friendly and safe way. In addition, the climatic changes occurring on our planet open up additional prospects for the use of the Arctic for economic purposes, in particular, the use of the Northern Sea Route for cargo transportation. In the modern world economy, sea cargo transportation accounts for about 80% of all cargo transportation. The main cargo flow is carried out through the Southern Sea Route (SSR), along which goods are transported from Europe to Asia. For quite a long period of time, shipowners and logistics companies did not perceive the Arctic region as an alternative to traffic from Asia to Europe or North America, while navigation in the Arctic was much more than just transport shipping. At the same time, the situation has changed significantly in the 21stcentury. The interest in this region among the states of the Arctic zone, as well as other countries, is connected not only with the presence there of large reserves of mineral resources, solving geopolitical problems, but also the search for alternative sea routes for cargo transportation between Europe, North America and Asia. In connection with the blockade of the Suez Canal in March 2021, the question of the need to redirect cargo transportation to alternative routes – the Northern Sea Route (NSR), as part of the Northeast Passage, and the Northwest Passage became acute. The Suez Canal is the busiest and longest sea artery. In addition, this area is unsafe due to frequent attacks by pirates. Due to the geographical features of the SSR the presence of sufficiently narrow places along the route - under the condition of increasing traffic, does not contribute to the free passage of ships. Meanwhile, the active melting of the Arctic ice in the foreseeable future will allow navigation along Arctic routes at higher latitudes and without the escort of icebreaker transport. All of the above allows us to consider navigation in the Arctic latitudes as an actual alternative to the Southern Route, which will serve as the beginning of sustainable development of the Arctic region

The use of digital technologies in the administration of justice in the field of environmental crime

In the present paper the authors consider technological and legal problems that arise in the course of adopting information technology in legal proceedings. The authors analyze the efficiency of using digital technologies in the administration of justice within the crisis period of 2020 on the basis of the World Justice Project, worked out by the Council of European Commission for the Efficiency of Justice CEPEJ. These technologies are used by both courts of the Russian Federation and courts of some other countries. The paper presents the analysis of prospects to apply artificial intelligence in the work of courts during adjudication on certain categories of disputes (issuance of a court order, consideration of cases as summary judgment proceedings). In order to ensure accessibility of justice, the authors urge on necessity to turn to online legal proceedings; they also highlight the necessity to organize special legal services for individuals (free-of-charge) and for business entities. The paper calls for the urgency to create a special digital portal for pretrial settlement of disputes between legal entities

The Influence of Co Additive on the Sintering, Mechanical Properties, Cytocompatibility, and Digital Light Processing Based Stereolithography of 3Y-TZP-5Al2O3 Ceramics

Nanocrystalline 3 mol% yttria-tetragonal zirconia polycrystal (3Y-TZP) ceramic powder containing 5 wt.% Al2O3 with 64 m2/g specific area was synthesized through precipitation method. Different amounts of Co (0–3 mol%) were introduced into synthesized powders, and ceramic materials were obtained by heat treatment in the air for 2 h at 1350–1550 °C. The influence of Co addition on the sintering temperature, phase composition, microstructure, mechanical and biomedical properties of the obtained composite materials, and on the resolution of the digital light processing (DLP) printed and sintered ceramic samples was investigated. The addition of a low amount of Co (0.33 mol%) allows us to decrease the sintering temperature, to improve the mechanical properties of ceramics, to preserve the nanoscale size of grains at 1350–1400 °C. The further increase of Co concentration resulted in the formation of both substitutional and interstitial sites in solid solution and appearance of CoAl2O4 confirmed by UV-visible spectroscopy, which stimulates grain growth. Due to the prevention of enlarging grains and to the formation of the dense microstructure in ceramic based on the tetragonal ZrO2 and Al2O3 with 0.33 mol% Co the bending strength of 720 ± 33 MPa was obtained after sintering at 1400 °C. The obtained materials demonstrated the absence of cytotoxicity and good cytocompatibility. The formation of blue CoAl2O4 allows us to improve the resolution of DLP based stereolithographic printed green bodies and sintered samples of the ceramics based on ZrO2-Al2O3. The developed materials and technology could be the basis for 3D manufacturing of bioceramic implants for medicine

Cryostructuring of Polymeric Systems: 63. Synthesis of Two Chemically Tanned Gelatin-Based Cryostructurates and Evaluation of Their Potential as Scaffolds for Culturing of Mammalian Cells

Various gelatin-containing gel materials are used as scaffolds for animal and human cell culturing within the fields of cell technologies and tissue engineering. Cryostructuring is a promising technique for the preparation of efficient macroporous scaffolds in biomedical applications. In the current study, two new gelatin-based cryostructurates were synthesized, their physicochemical properties and microstructure were evaluated, and their ability to serve as biocompatible scaffolds for mammalian cells culturing was tested. The preparation procedure included the dissolution of Type A gelatin in water, the addition of urea to inhibit self-gelation, the freezing of such a solution, ice sublimation in vacuo, and urea extraction with ethanol from the freeze-dried matter followed by its cross-linking in an ethanol medium with either carbodiimide or glyoxal. It was shown that in the former case, a denser cross-linked polymer phase was formed, while in the latter case, the macropores in the resultant biopolymer material were wider. The subsequent biotesting of these scaffolds demonstrated their biocompatibility for human mesenchymal stromal cells and HepG2 cells during subcutaneous implantation in rats. Albumin secretion and urea synthesis by HepG2 cells confirmed the possibility of using gelatin cryostructurates for liver tissue engineering

Strontium Substituted β-Tricalcium Phosphate Ceramics: Physiochemical Properties and Cytocompatibility

Sr2+-substituted β-tricalcium phosphate (β-TCP) powders were synthesized using the mechano-chemical activation method with subsequent pressing and sintering to obtain ceramics. The concentration of Sr2+ in the samples was 0 (non-substituted TCP, as a reference), 3.33 (0.1SrTCP), and 16.67 (0.5SrTCP) mol.% with the expected Ca3(PO4)2, Ca2.9Sr0.1(PO4)2, and Ca2.5Sr0.5(PO4)2 formulas, respectively. The chemical compositions were confirmed by the energy-dispersive X-ray spectrometry (EDX) and the inductively coupled plasma optical emission spectroscopy (ICP-OES) methods. The study of the phase composition of the synthesized powders and ceramics by the powder X-ray diffraction (PXRD) method revealed that β-TCP is the main phase in all compounds except 0.1SrTCP, in which the apatite (Ap)-type phase was predominant. TCP and 0.5SrTCP ceramics were soaked in the standard saline solution for 21 days, and the phase analysis revealed the partial dissolution of the initial β-TCP phase with the formation of the Ap-type phase and changes in the microstructure of the ceramics. The Sr2+ ion release from the ceramic was measured by the ICP-OES. The human osteosarcoma MG-63 cell line was used for viability, adhesion, spreading, and cytocompatibility studies. The results show that the introduction of Sr2+ ions into the β-TCP improved cell adhesion, proliferation, and cytocompatibility of the prepared samples. The obtained results provide a base for the application of the Sr2+-substituted ceramics in model experiments in vivo

Effects of Heat Treatment on Phase Formation in Cytocompatible Sulphate-Containing Tricalcium Phosphate Materials

Powders based on β-tricalcium phosphate (β-TCP) containing sulphate groups at up to 12.0 mol.% were synthesised by chemical precipitation from aqueous solutions. The obtained materials were characterised by X-ray phase analysis, Fourier transform infrared spectroscopy, measurement of specific surface area, scanning electron microscopy, energy dispersive analysis, synchronous thermal analysis, mass spectra investigations and biological assays. It was established that during the synthesis, the obtained materials lose the sulphate groups in the course of heat treatment at 900 or 1200 °C. These groups stabilise low-temperature β-TCP, but when introduced at a high concentration, the sulphate groups contribute to the formation of hydroxyapatite during the heat treatment. Specific surface area of the powders proved to be in the range 81.7–96.5 m2/g. Results of biological assays showed cytocompatibility of both pure β-TCP and samples of sulphate-containing β-TCP. Additionally, matrix properties in the culture of MG-63 cells were revealed in all samples. Thus, the obtained materials are promising for biomedical applications

Effects of Heat Treatment on Phase Formation in Cytocompatible Sulphate-Containing Tricalcium Phosphate Materials

Powders based on β-tricalcium phosphate (β-TCP) containing sulphate groups at up to 12.0 mol.% were synthesised by chemical precipitation from aqueous solutions. The obtained materials were characterised by X-ray phase analysis, Fourier transform infrared spectroscopy, measurement of specific surface area, scanning electron microscopy, energy dispersive analysis, synchronous thermal analysis, mass spectra investigations and biological assays. It was established that during the synthesis, the obtained materials lose the sulphate groups in the course of heat treatment at 900 or 1200 °C. These groups stabilise low-temperature β-TCP, but when introduced at a high concentration, the sulphate groups contribute to the formation of hydroxyapatite during the heat treatment. Specific surface area of the powders proved to be in the range 81.7–96.5 m2/g. Results of biological assays showed cytocompatibility of both pure β-TCP and samples of sulphate-containing β-TCP. Additionally, matrix properties in the culture of MG-63 cells were revealed in all samples. Thus, the obtained materials are promising for biomedical applications