Current issue

The Kaliningrad region, as a Russian exclave located at the center of the Baltic region, has found itself at the epicenter of geopolitical confrontation between the Russian Federation and the collective West. With the launch of the Special Military Operation in Ukraine, confrontation with NATO, the European Union, and regional states has reached its peak. The geographical position of the Kaliningrad region has generated threats of transport and economic blockade, while simultaneously enhancing its military and strategic significance as a Russian outpost. The article analyzes the key challenges facing the Kaliningrad region, including its exclave status, sanctions pressure, restrictions on cargo transit through Lithuania, the militarization of the region, and threats of a maritime blockade. It examines the evolution of policies pursued by the Baltic states aimed at isolating the region, as well as Russia’s response measures, including military and political actions. Particular attention is paid to the region’s economic adaptation, including the development of maritime transport, energy security, and the search for new logistics routes under the impact of sanctions. The growing importance of the Baltic Sea as a key transport corridor is emphasized. The study demonstrates that, amid escalating confrontation with the West, the Kaliningrad region is compelled to combine the strengthening of its defense potential with the search for sustainable economic development models that make it possible to minimize risks and maintain control over key transport routes.

The relevance of the study stems from the need to reduce interregional disparities, as stipulated in strategic planning documents. The article examines the provision of federal highways for key settlement centers in the Northwestern Federal District in the context of forming a sustainable socio-economic system. The methodological framework relies on the comparative geographical method and methods of geoinformation analysis, including the construction of buffer zones. The analysis reveals significant spatial heterogeneity in the district’s transport network, driven by historical and natural-climatic factors, and identifies territories with low levels of provision that require additional strategic planning measures. The study establishes that, although federal highways form the transport framework and ensure connectivity, their high density and level of integration are characteristic primarily of the southwestern regions of the district. The findings confirm the hypothesis that federal roads can serve as vectors of socio-economic development for territories.

The analysis of multidimensional raw data on the state of aquatic ecosystems often requires the use of modern analytical tools capable of identifying hidden patterns. The purpose of this study is to analyze long-term water quality monitoring data for the Pregolya River (Kaliningrad) in order to identify the main factors determining variability in the hydrochemical regime and to assess their temporal dynamics. To analyze data on indicators of the nitrogen and phosphorus cycles, methods of multivariate statistics were applied, including hierarchical cluster analysis (Ward’s method), factor analysis (minimum residual method with varimax rotation), and time-series analysis (LOESS smoothing). As a result of the cluster analysis, three groups of observations were identified, reflecting different periods of nutrient input. Factor analysis made it possible to identify two latent factors: “nitrogen load from organic sources” and “the ratio of organic and mineral forms of nitrogen.” Time-series analysis of factor scores revealed nonlinear dynamics and long-term trends in changes in water quality. The study demonstrates that the integrated application of chemometric methods serves as an effective tool for diagnosing the condition of urban water bodies, identifying pollution sources, and providing a scientific basis for the development of management decisions in the field of water resource protection.

A comparative study of the acute oral toxicity of the neonicotinoid insecticides imidacloprid and thiacloprid with respect to honey bees (Apis mellifera) was conducted. Under laboratory conditions, survival dynamics, changes in locomotor activity, and the repellent effect were examined under exposure to various concentrations of these compounds. The study established that both insecticides exhibit pronounced toxicity toward honey bees; however, their modes of action differ. Imidacloprid shows a more rapid onset of toxic effects, whereas thiacloprid develops toxicity more gradually. Analysis of behavioral activity demonstrated that both insecticides cause a sequential suppression of locomotor functions, followed by the development of hyperactivity typical of the neurotoxic effects of neonicotinoids. Assessment of repellent activity using the coefficient of protective action revealed a dose-dependent reduction in food consumption by bees under the influence of both substances.

Modern urban environments are characterized by high levels of light pollution, which negatively affect the adaptive mechanisms of the human body and cause various disorders and impairments of vital functions. This study focuses on changes in adaptive processes in the bodies of young people exposed to different lighting conditions—natural illumination and complete absence of light. The research employed heart rate variability (HRV) analysis using specialized equipment (Omega-M). The obtained data indicate significant differences in the functioning of the main regulatory systems of the body under changing lighting conditions. The study reveals that artificial light exposure disrupts normal biorhythmological processes, weakens the body’s resistance to external stressors, and increases the risk of pathological conditions. The results highlight the role of natural lighting cycles in maintaining normal homeostasis and ecological stability of the human body in a modern urbanized environment. Prolonged exposure to complete darkness exerts a destabilizing effect on the autonomic nervous system, reducing the body’s adaptive capacity. This leads to an imbalance between sympathetic and parasympathetic regulation, manifested in increased activity of stress-related mechanisms.

The aim of the study is to investigate the relationship between the cold tolerance of Vigna samples and their susceptibility to pathogenic micromycetes. Ten Vigna unguiculata samples were used. Pollen viability in vitro was assessed in a 20 % PEG 6000 solution at 25 °C for 3 hours (control) and at 6 °C for 24 hours (cold tolerance assessment). Seed germination under low temperatures was evaluated by germinating seeds on filter paper at 10, 12, and 25 °C (control), as well as in soil at a constant 25 °C and under a regime of 10 °C for 10 days followed by 25 °C. Root system adaptability to low temperatures was determined by growth rate under a 25 °C → 14 °C regime and by the ratio of growth rates at low versus optimal temperatures. Correlations between traits were analyzed using SPSS and Excel. The study revealed significant differences among Vigna samples in cold tolerance and susceptibility to pathogenic micromycetes. A significant negative correlation was found between pollen cold tolerance (0—97.9 %) and seed infection rate, as well as between seed germination at low temperature (0—77.7 %) and infection percentage. Pollen cold tolerance showed a significant positive correlation with seed germination on filter paper at 10 °C (r = 0.787; p < 0.01) and with overall seed cold tolerance (r = 0.757; p < 0.05). Samples with high germination after recovery from cold exposure exhibited lower rates of seed rot. Furthermore, the study identified correlations among the cold tolerance of pollen, seeds, and the root system. The Zinder and Fakir varieties demonstrated the best overall performance, combining high cold tolerance with low seed rot rates. This research provides a theoretical basis for the selection of Vigna cultivars for stress resistance.

The study investigated the effectiveness of composite gold-cobalt ferrite nanoparticles (Au@CFO) in photothermal and magnetomechanical therapy on human hepatocarcinoma Huh7 cells. The nanoparticles demonstrated significant activity during in vitro photothermal therapy and exhibited inherent cytotoxicity, reducing cell viability by 32 % at a concentration of 100 µg/mL. Photothermal therapy using an 808 nm laser further decreased viability by 25 %, while magnetomechanical therapy in an alternating field of 100 mT reduced Huh7 cell viability by an additional 17 %. Combined photothermal and magnetomechanical therapy resulted in a 47 % reduction in hepatocarcinoma cell viability compared to the control group. However, its direct efficiency was 14 %, as confirmed by fluorescence microscopy. The results highlight the potential of Au@CFO nanoparticles for the development of combined cancer treatment strategies.

A current challenge in soybean cultivation is the development of biological inoculants based on symbiotic nitrogen-fixing microorganisms, which provide the crop with the necessary amount of nitrogen for full plant development and sufficient protein accumulation. In particular, biological inoculants containing live nitrogen-fixing microbial cells are in high demand. Nodulating bacteria of the genus Bradyrhizobium are considered promising candidates for such inoculants. The aim of this study was to isolate and investigate Bradyrhizobium japonicum and Bradyrhizobium elkanii and to develop a microbiological seed inoculant based on these bacteria. Optimal cultivation conditions were determined to achieve the maximum titer of viable bacterial cells. A microbiological inoculant composition was developed, and a prototype was created. Field trials of the experimental samples of the new bioproduct were conducted. The study demonstrates the effectiveness of the developed inoculant containing Bradyrhizobium japonicum and Bradyrhizobium elkanii in soybean cultivation.