Recent publications
Purpose. Assessment of the ecological and reclamation state of the soil and the probable risks when using different types of irrigation: traditional sprinkling and subsurface drip irrigation. Methods. Field, laboratory analytical, Hakanson's method Results. Diagnostic soil indicators characterizing soil degradation processes and the degree of their development were analyzed in the experimental plots of lawn and thuja, using sprinkling and subsurface drip irrigation. Regarding the state of the soil, it was determined: Both types of irrigation (drip and rain) have a positive effect on soil density; organic matter in the soil decomposes faster than it is formed; the fastest degradation of organic matter is observed under the lawn with drip irrigation, which indicates a lack of nitrogen available to plants; nitrogen is the main limiting factor for plant growth with both types of irrigation. It is also determined that it is necessary to regularly apply nitrogen fertilizers to the lawn, especially at the beginning of the growing season; small doses of nitrogen fertilizers in the spring are sufficient for thuja; complex microfertilizers of prolonged action are required to eliminate copper and zinc deficiencies. It is also necessary to monitor the quality of irrigation water to avoid soil contamination. The level of soil contamination with heavy metals is low. Conclusions. Both types of irrigation have both positive and negative sides. To obtain optimal results, it is necessary to regularly conduct soil analysis and apply the necessary fertilizers. Particular attention should be paid to the quality of irrigation water. There is a small risk of increasing environmental risk over time.
This study investigates the design of electromagnetic devices, specifically wave rotators and cloaks, utilizing a polar rose-shaped structure. By applying the principles of transformation optics, the constitutive parameters – permittivity and permeability tensors – are analytically derived for transforming virtual space in cylindrical coordinates to physical space in Cartesian coordinates. Both integer and fractional indices of the rose configurations are considered, each yielding distinct electromagnetic properties. The analytical findings are validated and supported by numerical simulations conducted using COMSOL Multiphysics. The results highlight the tunability and adaptability of the proposed structures in controlling electromagnetic wave propagation, exhibiting rotational dynamics, cloaking, and absorption phenomena. Potential applications of these rose-shaped structures are briefly discussed.
Understanding the factors governing grassland biodiversity across different spatial scales is crucial for effective conservation and management. However, most studies focus on single grain sizes, leaving the scale‐dependent mechanisms of biodiversity drivers unclear. We investigated how climate, soil properties, abiotic disturbance, and land use influence plant diversity across two fine spatial scales in various grassland types in Ukraine. Using spatially explicit data on plant species presence and their cover, collected at smaller (10 m²) and larger (100 m²) grain sizes, we assessed spatial β‐diversity—the variability of biodiversity between scales. We analyzed whether the effects of ecological drivers on β‐diversity are mediated by changes in species evenness, density (total cover), and intraspecific aggregation in plant community. In our study, the most influential factors of local plant diversity at both grain sizes were climate variables, followed by soil humus content, litter cover, and soil pH. Soil and litter effects were primarily driven by the response of locally rare species, while climate and grazing effects were driven by locally common species. The strength of most of these effects varied between spatial scales, affecting β‐diversity. Soil properties influenced β‐diversity through changes in total plant community cover, while the effects of climate and litter operated via changes in species evenness and aggregation. Our findings highlight that biodiversity responses to climate, soil factors, and litter depend on the size of the sampled area and reveal the role of total plant cover, evenness, and aggregation in driving fine‐scale β‐diversity in grasslands across different habitat types.
- A. Agrawal
- V. V. Alenkov
- Poonam Aryal
- [...]
- Q. Yue
The AMoRE collaboration searches for neutrinoless double beta decay of 100 Mo using molybdate scintillating crystals via low temperature thermal calorimetric detection. The early phases of the experiment, AMoRE-pilot and AMoRE-I, have demonstrated competitive discovery potential. Presently, the AMoRE-II experiment, featuring a large detector array with about 90 kg of 100 Mo isotope, is under construction. This paper discusses the baseline design and characterization of the lithium molybdate cryogenic calorimeters to be used in the AMoRE-II detector modules. The results from prototype setups that incorporate new housing structures and two different crystal masses (316 g and 517–521 g), operated at 10 mK temperature, show energy resolutions (FWHM) of 7.55–8.82 keV at the 2.615 MeV 208 Tl γ line and effective light detection of 0.79–0.96 keV/MeV. The simultaneous heat and light detection enables clear separation of alpha particles with a discrimination power of 12.37–19.50 at the energy region around 6 Li ( n , α ) 3 H with Q-value = 4.785 MeV. Promising detector performances were demonstrated at temperatures as high as 30 mK, which relaxes the temperature constraints for operating the large AMoRE-II array.
This study investigates a bifunctional cloak composed of concentric metamaterials arranged in 4N thin layers, where N denotes the number of periodic layer pairs within the structure. The structure includes an inner circular domain, an outer domain, and alternating sequences of 2N layers between them. We explore two models: one using isotropic materials and another one using anisotropic materials. The anisotropic model demonstrates superior cloaking performance for both electrical and thermal fields. Analytical solutions based on the Effective Medium Theory and boundary-value problems reveal the structure’s response under quasi-static conditions. Numerical simulations using COMSOL validate these findings, highlighting the cloak’s and concentration’s ability to manipulate external thermal and electric fields efficiently.
We consider a free-falling observer who crosses the event horizon in the Schwarzschild background. In the course of this fall, he/she can receive signals from an object (like a star surface) that emits radiation. We study how the frequency received by an observer changes depending on the proper time on his/her trajectory. The scenarios are classified depending on whether the frequency is infinite, finite or zero near the singularity and the horizon. This depends crucially on the angular momenta of an observer and a photon. In this work we consider also emission process, and, as we show, conditions of emission strongly influence parameters of a photon, and thus received frequency. As one of our main results, we present numerical calculations showing evolution of the received frequency during the process of diving into a black hole, depending on parameters of an observer and emitter. We also analyze how a falling observer will see a night sky as he/she approaches the singularity. We show that there appear several blind zones, which were not analyzed previously.
Dielectric metasurfaces are a promising platform for implementing lasers and sensors. This paper proposes a metasurface operated on a trapped mode that strongly responds to gain–loss perturbations. The metasurface under study is made of dielectric disk-shaped resonators regularly arranged on a thick substrate and covered by a superstrate. The perturbations are caused by the inhomogeneity of the doping of the superstrate or semiconductor disks. The randomized Weierstrass function describes the dielectric properties of an inhomogeneous substance. The presence of inhomogeneity in the constitutive material leads to the appearance of radiative losses, which in turn results in the trapped mode excitation in the metasurface. Thus, the resonance quality factor can be considered as a measure of the inhomogeneity in the doped material.
We explore the ways in which elite crimes impact the development of society, and specifically address the harmful impact of such activities on social trust. We single out the issue of corruption in Ukraine during the Russian war to analyse the ways in which political elites exploit social trust in emergency situations. Employing a critical criminological approach to crime and justice, we analyse the effect of anti-corruption reforms in Ukraine, paying particular attention to the issue of trust to consider how and why trust has been “weaponized” by war. The war has changed Ukrainian attitudes towards state authorities and engendered in them a remarkably high degree of trust. We hypothesise that this change is based more on emotion than on rationality. The understanding of how and why the political elite might use this trust in the future is important for the development of anti-corruption policy both in Ukraine and generally in Europe. We conclude that the weaponization of trust poses a number of risks to advancing anti-corruption efforts in Ukraine. Sustaining progress in this area, therefore, will require a careful navigation of competing wartime priorities.
The kinetic regularities of the electrօspark sintering of SiC–TiC, SiC–VC composites at a pressure of 45 MPa and the temperatures of 1900 and 2000 °C have been established. At the first stage of the composite compaction process, the addition of TiC, VC impurities in the amount of 20 vol.% to silicon carbide with a dispersion of 2 μm increases the compaction rate by 1.3 and 1.1 times, respectively, and the addition of Ti, V carbides in the amount of 40 vol.% increases the compaction rate by 1.7 and 1.2 times, respectively. At the second stage of the compaction process, when Ti, V carbides are added in the amount of 40 vol.%, the compaction increases from 70% in silicon carbide to 99.9% in the 60SiC–40TiC composite and 91.2% in the 60SiC–40VC composite. Solid-phase sintering in composites with an admixture of titanium carbide is better than in composites with an admixture of vanadium carbide due to an increase in interaction at the phase boundaries: the interaction zone increases from ~1.0 μm at the boundaries of silicon carbide and vanadium carbide grains to ~1.5 μm at the boundaries of silicon carbide and titanium carbide grains.
The North Pontic region, which encompasses present-day Ukraine, was a crossroads of migration, connecting the vast Eurasian Steppe with Central Europe. We generated shotgun-sequenced genomic data for 91 individuals dating from around 7000 BCE to 1800 CE to study migration and mobility history in the region, with a particular focus on historically attested migrating groups during the Iron Age and the medieval period. We infer a high degree of temporal heterogeneity in ancestry, with fluctuating genetic affinities to different present-day Eurasian groups. We also infer high heterogeneity in ancestry within geographically, culturally, and socially defined groups. Despite this, we find that ancestry components which are widespread in Eastern and Central Europe have been present in the Ukraine region since the Bronze Age. In short, our study reveals a diverse range of ancestries in the Ukraine region through time as a result of frequent movements, assimilation, and contacts.
AMoRE-II aims to search for neutrinoless double beta decay ( 0 ν β β ) with an array of 423 Li 2 100 MoO 4 crystals operating in the cryogenic system as the main phase of the Advanced Molybdenum-based Rare process Experiment (AMoRE). AMoRE has been planned to operate in three phases: AMoRE-pilot, AMoRE-I, and AMoRE-II. AMoRE-II is currently being installed at the Yemi Underground Laboratory, located approximately 1000 m deep in Jeongseon, Korea. The goal of the experiment is to reach an exclusion half-life sensitivity to the 0 ν β β of 100 Mo on the level of T 1 / 2 0 ν β β > 6 × 10 26 year that covers completely the inverted Majorana neutrino mass hierarchy region of (15–46) meV. To achieve this, the background level of the experimental configurations and possible background sources of gamma and beta events should be well understood. We have intensively performed Monte Carlo simulations using the GEANT4 toolkit in all the experimental configurations with potential sources. We report the estimated background level that meets the 10 - 4 counts/(keV · kg · year) requirement for AMoRE-II in the Region Of Interest (ROI) and show the projected half-life sensitivity based on the simulation study.
Distal ulcerative colitis (DUC), affecting 30–50% of ulcerative colitis (UC) patients, is a subtype characterized by inflammation limited to the rectum and sigmoid colon. The pathogenesis involves a complex interplay of genetic, environmental, and immune factors, with cytokines like TNF-α, IL-1β, IL-6, and IL-17 playing significant roles. Despite therapeutic advancements, distal ulcerative colitis presents unique challenges due to its localized nature and diverse response to treatments. This review examined 50 randomized controlled trials (RCTs) that explored pharmacological and non-pharmacological interventions for distal ulcerative colitis, focusing on symptom remission, mucosal healing, and quality-of-life outcomes. Key findings revealed that pharmacologic treatments, particularly 5-aminosalicylic acid (5-ASA), corticosteroids, and biologics, effectively achieved remission, with combined therapies beneficial in refractory cases. Non-pharmacologic strategies, including lifestyle modifications and patient education, further supported treatment efficacy by enhancing patient adherence and outcomes. Importantly, trials highlighted that individualized approaches – such as early biologic therapy for patients with moderate-to-severe disease, dose adjustments based on patient demographics, and tailored lifestyle recommendations – enhanced treatment response and patient quality of life. The review underscores the necessity of personalized management strategies that integrate these findings to address distal ulcerative colitis’s heterogeneous nature and improve long-term patient outcomes.
The objective: to learn modern medical-and-social features at infertility in a matrimonial pair.Materials and methods. There was surveyed 100 matrimonial pair with infertility, a representative selection was here formed in quality and amounts with the use of method of systematic random sample.For the study of medical-and-social description of patients, exposure of facts of risk, determination of level of knowledges through question of maintaining and restoring in a reproductive health a statistical method was used, method of copies from ambulatory maps, survey of patients. In addition, on this stage of research by us social, economic and domestic factors which determine a reproductive health were certain. 133126 виченеясуачиа62х6емдкченеясуовід наукових досліджень до практики | Perinatology and reproductology:from research to practiceNo4-1 Vol. 4 • 2024ISSN 2788-6190БЕЗПЛІДДЯResults. The results of the conducted researches testify that medical-and-social factors matter very much for the decision of question of realization of reproductive function in matrimonial pair. A basic value is had the state of reproductive health of not only woman but also man or partner, and also maintaining of stage of grant of the specialized medical care, beginning from women’s consultation and concluding the specialized clinics of assisted reproductive technologies. Conclusions. The got results must be taken into account at the grant of medical care to the matrimonial pair with violation of reproductive function.Keywords: combined forms of infertility, medical-and-social factors, assisted reproductive technologies.
Increasing the energy efficiency level of buildings is crucial for recovering the Ukrainian economy and resolving the dependence on external energy sources. This study presents a toolkit of scientific and methodical approaches to the infrastructural and marketing support of energy-saving systems, allowing one to solve the existing problems in the national energy sector systematically. Based on monitoring the results, practical strategies for further development have been identified, aimed at constantly increasing energy efficiency, energy sustainability, economic security, and scaling up energy efficiency programs. It has been established that the technical and economic substantiation of energy-saving projects based on assessing energy costs and economic effect levels allows the creation of a foundation for involving new participants in scaling up positive experiences. The energy-saving system infrastructure and marketing support are vital in implementing national economy recovery projects by stimulating the demand for energy-efficient solutions and the transition to sustainable development. The practical implementation of this approach in the example of one communication and logistics infrastructure facility made it possible to reduce the cost of heat energy consumption by 5.8 times. The discounted payback period for the implemented energy-saving measures ranges from 0.16 to 3.16 years. Scaling this project will expand the influence of energy efficiency processes on other critical infrastructure facilities, increase the overall energy efficiency level in various economic sectors, reduce dependence on energy sources, and contribute to preserving natural resources and reducing their negative impact on the environment.
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