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The optimized system of forest strips in Ukraine had been developed on the landscape and ecological bases in order to ensure the formation of a sustainable agroforestry landscape; stabilize the ecological state, preserve the natural resource potential of a studied area, and create optimal conditions for the growth, development, and productivity of agricultural crops. Over nearly a hundred years, there have been developed the principles of combining tree and shrubby species, optimal designs of forest strips, their width parameters, species composition and placement of planting groupings, and their location in the fields. Also, agrotechnical and forestry measures for their care were designed in different soil and climatic conditions of Ukraine. All accounted factors would provide the maximum ecological and economic effects with a minimum planting. The paper presents the results of phytodiversity study and initiated studies of the syntaxonomy of field-protective forest strips in the regions of Ukraine. The issues of the global practice of field-protective afforestation, which is part of the newest direction -- agroforestry, were highlighted. They combine the simultaneous cultivation of tree and shrubby species and agricultural crops in the same areas for environmental, economic, and social benefits. The authors analyzed the current situation related to forest strips in Ukraine and described the negative changes that have occurred over the past thirty years. Mitigation of natural and anthropogenic threats in agricultural lands is a chalange due to the lack of comprehensive land-reclamation measures in agricultural landscapes and the strengthening of degradation processes caused by the global climate change. We conducted analysis and assessment of the state of forest strips and changes they have underwent because of military operations, concluding that optimizing the windbreak system in Ukraine as a particularly effective environment-forming factor is now especially relevant and requires research, updated using modern methods. For this purpose, one should take into account their intended purpose, spatial orientation, placement, optimal composition, considering typological characteristics, design parameters, and other forest-reclamation characteristics, identification of their syntaxonomic diversity, and identifying regularities in formation and differentiation and development of scientific bases of optimization. It would ensure the maximum efficiency of developing conditions for ecological rehabilitation of forest strips and increase their ecological capacity, and, in general, would promote balanced development of agroecosystems. Therefore, the objective of this paper was to analyze the current state of forest strips in Ukraine and substantiate the need to conduct priority measures to restore their functioning as forest-reclamation objects in connection with the latest circumstances in the conditions of military operations. [ABSTRACT FROM AUTHOR]

The article is a continuation of the study on ruderal vegetation of Kyiv City and provides summarized results of syntaxonomic research of the class Artemisietea vulgaris. We identified 14 associations and one derivative community belonging to three orders and four alliances. Using ordination and phytoindication analyses, the synmorphology of the communities, their ecological requirements, and habitat preferences were described. It has been shown that the vegetation of Artemisietea vulgaris is distributed throughout all districts of the city. According to ecological requirements, we found that main environmental gradients that determine the ordination of different types of stands of Artemisietea vulgaris within Kyiv City are thermoregime and light. The diversity of man-made habitats and regional environmental conditions appeared as the most important factors affecting the territorial differentiation of this vegetation type within the city. The contributed data can be used for strategic planning and practical implementation of measures for sustainable urban development and optimization of the urban environment.

The article is dedicated to the 35th anniversary of publication of the first edition of the Green Data Book of Ukraine. This publication was a notable event in the 100-year history of research activity in the M.G. Kholodny Institute of Botany of the National Academy of Sciences of Ukraine, where the scientific and methodological principles of the Green Data Books originated. The outcomes of the history and preconditions for development of a concept of the phytocenodiversity conservation are summarized. Problematic and disputable issues of the Green Data Book are discussed and some future tasks are outlined. Methodological approaches to conservation of natural units and areas are analyzed. It is emphasized that modern methods of biodiversity conservation are based on populational and ecosystemic approaches, while the main mode of conservation of plants is based on conservation of plant communities, which form a phytocenotic matrix for plant cenopopulations. Implementation of scientific principles of the Green Data Book of Ukraine in legislation and regulatory documents of Ukraine. A critical analysis of syntaxonomy of the protected plant communities in Ukraine is provided; 983 associations of 104 formations will form the basis for a new edition of the Green Data Book of Ukraine. The importance of wide public awareness among the general public, public organizations, and international bodies regarding the Green Data Book of Ukraine is emphasized.

In recent decades, knowledge about the role of epigenetic regulation of gene expression in plant responses to external stimuli and in adaptation of plants to adverse environmental fluctuations have extended significantly. DNA methylation is considered as the main molecular mechanism that provides genomic information and contributes to the understanding of the molecular basis of phenotypic variations based on epigenetic modifications. Unfortunately, the vast majority of research in this area has been performed on the model species Arabidopsis thaliana. The development of the methylation-sensitive amplified polymorphism (MSAP) method has made it possible to implement the large-scale detection of DNA methylation alterations in wild non-model and agricultural plants with large and highly repetitive genomes in natural and manipulated habitats. The article presents current information on DNA methylation in species of natural communities and crops and its importance in plant development and adaptive phenotypic plasticity, along with brief reviews of current ideas about adaptive phenotypic plasticity and epigenetic regulation of gene expression. The great potential of further studies of the epigenetic role in phenotypic plasticity of a wide range of non-model species in natural populations and agrocenoses for understanding the molecular mechanisms of plant existence in the changing environment in onto- and phylogeny, directly related to the key tasks of forecasting the effects of global warming and crop selection, is emphasized. Specific taxa of the Ukrainian flora, which, in authors’ opinion, are promising and interesting for this type of research, are recommended.

This article, which is the first contribution in a series on the ruderal vegetation of the city of Kyiv, presents results of our studies of Stellarietea mediae plant communities occurring in the city. Their current state and phytocoenotic diversity has been determined. Based on modern methods of statistical data analyses, a classification scheme of Stellarietea mediae vegetation in the study area was developed and the leading factors of territorial and ecological differentiation of phytocoenoses were identified. It has been established that within Kyiv City, this class is represented by 24 associations and 3 basal communities belonging to 8 alliances and 4 orders. Their territorial distribution determines the types and intensity of anthropogenic disturbances, as well as the types of soil and its mechanical structure. Selected syntaxa are characterized and compared with their equivalents from other areas of Ukraine. It has been found that the main differences are at the level of co-occurring species, the composition of which mostly correlates with the types of anthropogenic disturbances and availability of water and mineral nutrients. According to the results of the ordination, it has been found that the distribution patterns of plant communities of Stellarietea mediae occur along the salt regime gradient of the edaphotope, as well as of ombro-, cryo-, and thermal regimes of the climate. Based on the phytoindication analysis, the ecological optimums of the plant communities in relation to the leading ecological factors were determined. The performed research supplements the available information about the presence and distribution of such associations as: Digitarietum ischaemii, Setario viridis-Erigeronetum canadensis, and Ambrosietum artemisiifoliae, in the territory of Ukraine. The proposed syntaxonomic scheme should become a basis of typological developments for strategic planning and practical implementation of activities for optimizing the urban environment and for sustainable development of the Kyiv urban agglomeration.

The article presents the results of an analysis of the alien fraction of coenofloras of the classes of pioneer vegetation of Ukraine. In plant communities of the newly formed ecotopes, 113 alien species of 32 families and 88 genera were identified. A value of the general index of adventization of coenofloras of the classes of pioneer vegetation of Ukraine is 13.4%. The highest level of anthropogenization was established for the plant communities of Bidentetea, Cakiletea maritimae and Isoëto-Nanojuncetea. The leading families of the alien fraction of the studied coenofloras are Asteraceae, Brassicaceae and Poaceae. It has been revealed that terophytes prevail in the biomorphological spectrum of the alien fraction of coenofloras of the classes of pioneer vegetation in Ukraine. The ecological analysis of alien species has shown the predominance of the species with a very wide ecological plasticity in relation to all abiotic factors. It was established that in the investigated coenofloras kenophytes predominate by the time of immigration, and epecophytes – by the degree of naturalization. The analysis and comparison of species composition of the alien fractions of the typological floras of pioneer plant communities by means of Jaccard indices showed the highest similarity between the Isoëto-Nanojuncetea and Bidentetea classes, as well as Festucetea vaginatae and Helichryso-Crucianelletea maritimae. For determination of the degree of anthropogenic transformation of coenofloras of the classes of pioneer vegetation of Ukraine, the indexes of archeophytization, kenophytization, modernization and fluctuation of the flora have been calculated. It has been established that 26 species of 11 families and 25 genera are invasive. Among them, Amorpha fruticosa, Ambrosia artemisiifolia, Anisantha tectorum, Apera spica-venti, Bidens frondosa, Centaurea diffusa, Conyza canadensis, Echinocystis lobata, Elaeagnus angustifolia, Impatiens glandulifera, Solidago canadensis and Phalacroloma annuum are transformers, which constitute the greatest threat to pioneer vegetation due to their diverse impacts.

Protection of the diversity of plant communities as a functional basis of the biosphere, and particularly of its rare component, remains one of the priorities among major conservation issues. It is emphasized that the state of the rare plant communities in Ukraine has significantly changed over the last few decades. The main tendencies of the changes in rare phytocoenoses due to human activity are outlined. Three main groups of the consequences of transformation of rare phytocoenoses into derivative groups are as follows: 1 – within the same autochthonous formation; 2 – within other formation of the same vegetation type; 3 – within other formation of the other type of vegetation. For the each group, the key factors of the threats are presented and examples of the changes in the rare communities of the main vegetation types in Ukraine are provided. In the present article, natural changes of rare communities of the forest, steppe, meadow and marsh vegetation are characterized. In this context, authors consider changes in rare plant communities and formation of the altered vegetation due to successions in natural conservation areas under conditions of the continuous regime of strict protection. It is noted that conservation of rare phytocoenotic diversity requires transition to the system of preventive and direct methods as well as various conservation regimes, depending on a vegetation type and communities homeostasis. The authors propose to introduce changes into documents on nature conservation regarding the use of various protection regimes in the areas under strict protection. They should be used as regulatory measures to prevent degradation of natural ecosystems and progressing loss of zonal phytocoenotic diversity.

Aluminum nitride (AlN) film coatings have been obtained by a new technique of hybrid helikon-arc ion-plasma deposition. Possibility to combine the magnetic-filtered arc plasma deposition technique with a treatment in RF plasma of helicon discharge allowed us to deposit AlN coatings on thermolabile substrates, significantly increasing the deposition rate. A study of spectral properties of AlN films (reflection and transmission spectra within the range 2...25 μm) has been carried out by using the infrared Fourier spectrometer Spectrum BX-II. It has been shown that the obtained composite structures (AlN coatings on teflon and mylar substrates) could be used as passive filters in the infrared spectral range. [ABSTRACT FROM AUTHOR]

Superconducting quantum circuits are a natural platform for quantum simulations of a wide variety of important lattice models describing topological phenomena, spanning condensed matter and high-energy physics. One such model is the bosonic analog of the well-known fermionic Kitaev chain, a 1D tight-binding model with both nearest-neighbor hopping and pairing terms. Despite being fully Hermitian, the bosonic Kitaev chain exhibits a number of striking features associated with non-Hermitian systems, including chiral transport and a dramatic sensitivity to boundary conditions known as the non-Hermitian skin effect. Here, using a multimode superconducting parametric cavity, we implement the bosonic Kitaev chain in synthetic dimensions. The lattice sites are mapped to frequency modes of the cavity, and the in situ tunable complex hopping and pairing terms are created by parametric pumping at the mode-difference and mode-sum frequencies, respectively. We experimentally demonstrate important precursors of nontrivial topology and the non-Hermitian skin effect in the bosonic Kitaev chain, including chiral transport, quadrature wavefunction localization, and sensitivity to boundary conditions. Our experiment is an important first step towards exploring genuine many-body non-Hermitian quantum dynamics., (© 2024. The Author(s).)

A dynamical control of the coupling strengths between dressed states and probe photon states is demonstrated with a transmon-like artificial atom coupled to two closely spaced resonant modes. When the atom is driven with one mode, the atom state and driving photon states form the so-called dressed states. Dressed states with sideband index up to 3 were prepared and probed via the strong coupling to the other resonant mode. Spectroscopy reveals that the coupling strengths are "dressed" and can be modulated by the power and sideband index of the driving. The transmission of the probe tone is modulated by the driving microwave amplitude with a Bessel behavior, displaying multi-photon process associated with the inter-atomic level transitions., (© 2022. The Author(s).)

We experimentally study interactions between two microwave fields mediated by 3-level transmon artificial atom with two-photon processes. The transmon has good selection rule, preventing one-photon transition, but allowing two-photon transition from ground state(0) to 2nd excited state(2). By pumping a control tone in resonance to the transition between 1st(1) and 2nd excited state(2), we control the one-photon transparency for 0 to 1 transition and two-photon transparency for 0 to 2 transition. The results are explained by the Autler-Townes splitting induced by the control microwave. In addition, two possible microwave amplification processes involving two-photon processes are also studied. The 4-wave mixing scheme increases the transmission by 3% while 2-photon optical pumping produces a 11% narrowband increment. All these phenomena can be operated with control and probe tones in a narrow band.