246 research outputs found

    Landau Damping in a 2D Electron Gas with Imposed Quantum Grid

    Full text link
    Dielectric properties of semiconductor substrate with imposed two dimensional (2D) periodic grid of quantum wires or nanotubes (quantum crossbars, QCB) are studied. It is shown that a capacitive contact between QCB and semiconductor substrate does not destroy the Luttinger liquid character of the long wave QCB excitations. However, the dielectric losses of a substrate surface are drastically modified due to diffraction processes on the QCB superlattice. QCB-substrate interaction results in additional Landau damping regions of the substrate plasmons. Their existence, form and the density of losses are strongly sensitive to the QCB lattice constant.Comment: 9 pages, 12 eps-figure

    Dephasing of Local Vibrations in a Planar Lattice of Adsorbed Molecules

    Full text link
    We investigate anharmonically coupled high- and low-frequency excitations in a planar lattice of adsorbed molecules interacting with phonons of a crystal. Dephasing of high-frequency local vibrations by low-frequency resonance modes is described in terms of temperature Green's function. The equations obtained are solved, first, with a small ratio of the anharmonic coupling coefficient for high- and low-frequency modes to the resonance width, and second, in the low-temperature limit. High-frequency spectral line positions and widths depend on dispersion laws and resonance mode lifetimes. It is shown that lateral interactions of low-frequency modes of adsorbed molecules can lead to a significant narrowing of high-frequency spectral lines, which is consistent with experimental data.Comment: REVTeX, 11 pages, no figure

    Changes in peripheral blood indicators and hemostatic system in patients with uterine fibroids

    Get PDF
    The article presents the results of studying the parameters of peripheral blood and the system of coagulation of patients with uterine fibroids. The analyzed data indicate the presence of a pronounced chronic inflammatory process, which is confirmed by the relevant indicators. The obtained results correlate with the data obtained by other authors. Since in the course of preliminary studies, the expediency of using the buccal epithelium to confirm the diagnosis of "uterine fibroids" has been determined, the blood system parameters have been confirmed once again confirm the high-visibility of this technique

    Transformation of the national legislation of Ukraine in the context of globalization

    Get PDF
    The article studies the directions of transformation of the national legislation of Ukraine in the context of globalization based on the dialectical method. Specifically, the notions “legislation” and “globalization” are analyzed; the meaning of the concepts of “national legislation of Ukraine” and “legal globalization” is specified; the factors which define features of transformation of the national legislation of Ukraine in modern conditions of globalization are established. As a result of the study it is proved that the main directions of transformation of the national legislation of Ukraine in the conditions of globalization are the following: borrowing the European (Western) legal tradition and its adaptation to the national legal system of Ukraine; reception of innovative legal institutions while preserving the national legal tradition; the influence of international law, first of all, the Acquis communautaire (adaptation of the national legislation of Ukraine to the law of the European Union); hierarchical (vertical) and sectoral (horizontal) structure of legislation, which is characteristic of the legal systems of the Romano-Germanic legal family; development of such types of normative activity of public authorities as systematization, codification, ordering, unification, etc. &nbsp

    Effects of selenium on metabolic processes in the body of ducklings and their productive qualities

    Get PDF
    Today, indicators controlling poultry's mineral nutrition have significantly increased. However, the physiological need of various types and technological poultry groups for certain mineral elements that perform essential biochemical functions in the body has yet to be definitively established. This also applies to such an element as Selenium, which, according to modern classification, is recognized as an indispensable biotic ultramicroelement with a broad spectrum of biological action. The inclusion of Selenium in the composition of mixed feed for young poultry changes the direction of physiological and biochemical processes in the body and improves metabolism and, as a result, contributes to the increase in their live weight, viability, feed conversion, slaughter, and meat qualities, improvement of organoleptic indicators of meat, its amino acid composition, energy, and biological value. We conducted comprehensive scientific studies to deepen and expand modern ideas about the biological role of Selenium, its influence on the productive qualities, and internal indicators of ducklings in the postembryonic period of ontogenesis. One of the tasks was to study the causal relationship between the level of consumption of Selenium with feed by ducklings and the studied indicators. Experimental studies were conducted on ducklings of the Ukrainian white breed. Following existing standards, feeding ducklings daily to 56 days of age was carried out with complete mixed feeds, balanced in essential nutrients and biologically active substances. Ducklings of the first control group did not receive selenium supplementation in mixed feed. Poultry of experimental groups (2–4) was additionally injected with different amounts of Selenium, respectively, by 0.2 mg/kg, 0.4, and 0.6 mg/kg. When conducting a correlation analysis of the obtained experimental data, it was found that between the economically useful and interior features included in the analysis, there are different levels and directions of the relationship, which may vary depending on the level of selenium consumption by ducklings. A scheme of modeling the effect of Selenium on the ducklings’ organism raised for meat is proposed

    The influence of the drugs “Brovermectin-granulate TM” and “Avesstim TM” on indicators of non-specific resistance of one year-old carp fish infested with monogeneans

    Get PDF
    The article presents data on the study of the influence of the drugs “Brovermectin-granulate TM” and “Avesstim TM” on indicators of non-specific resistance of one-year-old carp fish infested with monogeneans. For conducting experiments, 14 experimental groups were formed (two groups of each species of fish affected by Dactylogyrus lamellatus, Gyrodactylus hypophthalmichtіdis, Eudiplozoon nipponicum ). The fish of the first experimental group were administered “Brovermectin-granulate TM”, and the second experimental group were administerec a complex of drugs “Brovermectin-granulate TM” and “Avesstim TM”. Fish infected with various ectoparasites (Dactylogyrus lamellatus, Gyrodactylus hypophthalmichtіdis, Eudiplozoon nipponicum ) served as controls. Fish of each group were kept in separate aquariums with a capacity of 40 dm3 with artificial aeration at a temperature of 20–22 °С. Their care and feeding was carried out according to the relevant norms and rations. During the entire period of research, the behavior and clinical condition of the fish were observed. The pre-experimental period of acclimatization of annuals was 7 days. The use of the drug “Brovermectin-granulate TM” to one-year-old white carp, crucian carp and scaly carp affected by monogeneans had a stimulating effect on the resistance of their organism. At the same time, the simultaneous use of the specified drug with the immunomodulator “Avesstim TM” contributed to better activation of the humoral link of non-specific immunity in sick fish. To normalize the organism homeostasis, correct metabolism and activate the humoral link of non-specific immunity during a monogenoid invasion of carp, it is recommended to feed them with a combined feed of the drugs “Brovermectin-granulate TM” and the immunomodulator “Avesstim TM”

    Optical Self Energy in Graphene due to Correlations

    Full text link
    In highly correlated systems one can define an optical self energy in analogy to its quasiparticle (QP) self energy counterpart. This quantity provides useful information on the nature of the excitations involved in inelastic scattering processes. Here we calculate the self energy of the intraband optical transitions in graphene originating in the electron-electron interaction (EEI) as well as electron-phonon interaction (EPI). Although optics involves an average over all momenta (kk) of the charge carriers, the structure in the optical self energy is nevertheless found to mirror mainly that of the corresponding quasiparticles for kk equal to or near the Fermi momentum kFk_F. Consequently plasmaronic structures which are associated with momenta near the Dirac point at k=0k=0 are not important in the intraband optical response. While the structure of the electron-phonon interaction (EPI) reflects the sharp peaks of the phonon density of states, the excitation spectrum associated with the electron-electron interaction is in comparison structureless and flat and extends over an energy range which scales linearly with the value of the chemical potential. Modulations seen on the edge of the interband optical conductivity as it rises towards its universal background value are traced to structure in the quasiparticle self energies around kFk_F of the lower Dirac cone associated with the occupied states.Comment: 30 pages, 10 figure

    Adaptive potential of spring durum wheat (<i>Triticum durum</i> Desf.) under the conditions of Primorsky Territory

    Get PDF
    Background. The research goal was to study spring durum wheat cultivars from different regions of Russia to select those that were most adapted to the conditions of Primorsky Territory and had high yield and grain quality.Materials and methods. The adaptive potential of 16 genotypes was determined through multi-environment trials at the Federal Scientific Center of Agricultural Biotechnology of the Far East named after A.K. Chaika in 2017–2021.Results. Considerable potential for high productivity was revealed in the cultivars: ‘Solnechnaya 573’ (3.9 t/ha), ‘Donskaya elegiya’ (3.8 t/ha), ‘Lyudmila’ (3.8 t/ha), ‘Omskii izumrud’ (3.8 t/ha), and ‘Voronezhskaya 7’ (3.8 t/ha). Cvs. ‘Pamyati Yanchenko’ (–2.1), ‘Zhemchuzhina Sibiri’ (–2.4), and ‘Voronezhskaya 7’ (–2.4) displayed significant stress resistance. ‘Lyudmila’ (4.2) and ‘Donskaya elegiya’ (4.0) had high genetic plasticity and produced high yields in the years with favorable conditions. The adaptability coefficient of cvs. ‘Solnechnaya 573’ (112.5%) and ‘Voronezhskaya 7’ (111.0%) exceeded 100%. ‘Donskaya elegiya’, ‘Lyudmila’, ‘Aleiskaya’, and ‘Voronezhskaya 9’ demonstrated the highest plasticity (bi &gt; 1). The most stable cultivars were ‘Omskii tsirkon’ (S2di – 0.00), ‘Pamyati Yanchenko’ (S2di – 0.02), ‘Voronezhskaya 7’ (S2di – 0.04), ‘Aleiskaya’ (S2di – 0.05), ‘Nikolasha’ (S2di – 0.06), and ‘Omskaya biryuza’ (S2di – 0.08). ‘Voronezhskaya 7’ and ‘Pamyati Yanchenko’ were able to produce an increased yield and had the minimum yield loss under unfavorable conditions (the indicator of the yield stability of the cultivars was 134.9 and 144.8, respectively). ‘Pamyati Yanchenko’ (4.8 and 1.9, respectively) and ‘Voronezhskaya 7’ (3.5 and 2.0, respectively) showed high homeostatic capacity and breeding value.Conclusions. ‘Voronezhskaya 7’ and ‘Solnechnaya 573’ were selected on the basis of complex evaluation for yield and adaptability under the local conditions. They can be recommended for further breeding and production
    corecore