51 research outputs found

    Low-energy three-body dynamics in binary quantum gases

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    The universal three-body dynamics in ultra-cold binary Fermi and Fermi-Bose mixtures is studied. Two identical fermions of the mass mm and a particle of the mass m1m_1 with the zero-range two-body interaction in the states of the total angular momentum L=1 are considered. Using the boundary condition model for the s-wave interaction of different particles, both eigenvalue and scattering problems are treated by solving hyper-radial equations, whose terms are derived analytically. The dependencies of the three-body binding energies on the mass ratio m/m1m/m_1 for the positive two-body scattering length are calculated; it is shown that the ground and excited states arise at m/m1λ18.17260m/m_1 \ge \lambda_1 \approx 8.17260 and m/m1λ212.91743m/m_1 \ge \lambda_2 \approx 12.91743, respectively. For m/m_1 \alt \lambda_1 and m/m_1 \alt \lambda_2, the relevant bound states turn to narrow resonances, whose positions and widths are calculated. The 2 + 1 elastic scattering and the three-body recombination near the three-body threshold are studied and it is shown that a two-hump structure in the mass-ratio dependencies of the cross sections is connected with arising of the bound states.Comment: 16 page

    Means of Cartographic Visualization in the Research of the Volyn Oblast Natural Reserve Fund Network

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    Formation of an effective system for the conservation of the nature of the region and solution of modern environmental problems are impossible without creating a cartographic scientific and information base on environmental objects and improving the use of geospatial data. Improving the system in order to meet the needs of society in all types of geographic information is very important in the field of information and education, because the safe conservation and restoration of natural resources is possible only with the participation of a wide environmentally conscious and responsible public. The thesis analyzes cartographic editions of oblast, including digital form, about the current state of natural components and landscapes

    Бальнеологічно-рекреаційний потенціал санаторію-профілакторію «Журавка»

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    Метою статті є оцінка природно-рекреаційного потенціалу санаторію-профілакторію «Журавка» для здійснення лікувально-оздоровчої діяльності, реабілітації постраждалих військовослужбовців неоголошеної війни в Україні, відпочинку та активізації туризму. Курортно-оздоровчий заклад руйнується впродовж кількох десятиліть, тому актуальним є питання швидкого відновлення функціонування установи

    Universal description of the rotational-vibrational spectrum of three particles with zero-range interactions

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    A comprehensive universal description of the rotational-vibrational spectrum for two identical particles of mass mm and the third particle of the mass m1m_1 in the zero-range limit of the interaction between different particles is given for arbitrary values of the mass ratio m/m1m/m_1 and the total angular momentum LL. If the two-body scattering length is positive, a number of vibrational states is finite for Lc(m/m1)LLb(m/m1)L_c(m/m_1) \le L \le L_b(m/m_1), zero for L>Lb(m/m1)L>L_b(m/m_1), and infinite for L<Lc(m/m1)L<L_c(m/m_1). If the two-body scattering length is negative, a number of states is either zero for LLc(m/m1)L \ge L_c(m/m_1) or infinite for L<Lc(m/m1)L<L_c(m/m_1). For a finite number of vibrational states, all the binding energies are described by the universal function ϵLN(m/m1)=E(ξ,η)\epsilon_{LN}(m/m_1) = {\cal E}(\xi, \eta), where ξ=N1/2L(L+1)\xi=\displaystyle\frac{N-1/2}{\sqrt{L(L + 1)}}, η=mm1L(L+1)\eta=\displaystyle\sqrt{\frac{m}{m_1 L (L + 1)}},and NN is the vibrational quantum number. This scaling dependence is in agreement with the numerical calculations for L>2L > 2 and only slightly deviates from those for L=1,2L = 1, 2. The universal description implies that the critical values Lc(m/m1)L_c(m/m_1) and Lb(m/m1)L_b(m/m_1) increase as 0.401m/m10.401 \sqrt{m/m_1} and 0.563m/m10.563 \sqrt{m/m_1}, respectively, while a number of vibrational states for LLc(m/m1)L \ge L_c(m/m_1) is within the range NNmax1.1L(L+1)+1/2N \le N_{max} \approx 1.1 \sqrt{L(L+1)}+1/2

    Peculiarities of the distribution of assimilates in the organs of Schisandra chinensis plants under different soil and climatic conditions

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    Peculiarities of accumulation of nutrients in the leaves of Schisandra chinensis (Turcz.) Baill. and rhizosphere soil under the conditions of its continuous monoculture have been studied. Comparative analysis of the distribution of nutrients in the leaves of plants under different soil and climatic conditions revealed significant differences. It was found that plants grown on podzolic chernozem of Kolomyia State Forest Fund (Otyniia, Ukraine) were characterized by more intensive absorption of such nutrients as Ca, Si, P, Cu, Zn and Mg. The content of P, K, S, Mn was much higher in the foliar tissues of S. chinensis plants cultivated on the territory of the M. Gryshko National Botanical Garden (Kyiv, Ukraine) in the conditions of dark grey forest soil. The high ability of plants to accumulate and release Mg into the rhizosphere soil was revealed, which is fully consistent with the selective ability of plants to release mineral elements into the soil environment in accordance with their ecomorphotypes. At the same time, the amount of Ca in the rhizosphere soil decreased significantly at the end of the vegetative period, which could be explained, on the one hand, by the intensive influx of Ca into plant tissues and, on the other hand, by participation in chemical balancing processes to reduce manganese and nitrogen mobility in the soil. Barrier-free accumulation of Fe, Ca, Mg, Al elements in S. chinensis leaves was revealed, which should be taken into account when developing plant cultivation technology. The studies of allelopathy activity of vegetative and generative organs of plants and rhizosphere soil have shown that phenolic substances accumulate in small amounts in the soil under S. chinensis, which is a prerequisite for successful cultivation of this fruit vine in the Forest-Steppe zone of Ukraine under conditions of continuous long-term cultivation. The largest amount of phenolic substances was in the upper soil horizons, which gradually decreased with depth, which is consistent with the course of redox processes for the studied soil profiles. The pool of free amino acids of S. chinensis plants growing in different soil and climatic conditions was analyzed, the concentration of amino acids in the leaves was the most indicative. Evaluation of the quantitative and qualitative distribution of free amino acids in plant tissues serves as a diagnostic sign of plant sensitivity to soil and climatic conditions

    The histone H2B monoubiquitination regulatory pathway is required for differentiation of multipotent stem cells.

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    Extensive changes in posttranslational histone modifications accompany the rewiring of the transcriptional program during stem cell differentiation. However, the mechanisms controlling the changes in specific chromatin modifications and their function during differentiation remain only poorly understood. We show that histone H2B monoubiquitination (H2Bub1) significantly increases during differentiation of human mesenchymal stem cells (hMSCs) and various lineage-committed precursor cells and in diverse organisms. Furthermore, the H2B ubiquitin ligase RNF40 is required for the induction of differentiation markers and transcriptional reprogramming of hMSCs. This function is dependent upon CDK9 and the WAC adaptor protein, which are required for H2B monoubiquitination. Finally, we show that RNF40 is required for the resolution of the H3K4me3/H3K27me3 bivalent poised state on lineage-specific genes during the transition from an inactive to an active chromatin conformation. Thus, these data indicate that H2Bub1 is required for maintaining multipotency of hMSCs and plays a central role in controlling stem cell differentiation

    Bound states and scattering lengths of three two-component particles with zero-range interactions under one-dimensional confinement

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    The universal three-body dynamics in ultra-cold binary gases confined to one-dimensional motion are studied. The three-body binding energies and the (2 + 1)-scattering lengths are calculated for two identical particles of mass mm and a different one of mass m1m_1, which interactions is described in the low-energy limit by zero-range potentials. The critical values of the mass ratio m/m1m/m_1, at which the three-body states arise and the (2 + 1)-scattering length equals zero, are determined both for zero and infinite interaction strength λ1\lambda_1 of the identical particles. A number of exact results are enlisted and asymptotic dependences both for m/m1m/m_1 \to \infty and λ1\lambda_1 \to -\infty are derived. Combining the numerical and analytical results, a schematic diagram showing the number of the three-body bound states and the sign of the (2 + 1)-scattering length in the plane of the mass ratio and interaction-strength ratio is deduced. The results provide a description of the homogeneous and mixed phases of atoms and molecules in dilute binary quantum gases

    The OTUD6B-LIN28B-MYC axis determines the proliferative state in multiple myeloma

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    Deubiquitylases (DUBs) are therapeutically amenable components of the ubiquitin machinery that stabilize substrate proteins. Their inhibition can destabilize oncoproteins that may otherwise be undruggable. Here, we screened for DUB vulnerabilities in multiple myeloma, an incurable malignancy with dependency on the ubiquitin proteasome system and identified OTUD6B as an oncogene that drives the G1/S-transition. LIN28B, a suppressor of microRNA biogenesis, is specified as a bona fide cell cycle-specific substrate of OTUD6B. Stabilization of LIN28B drives MYC expression at G1/S, which in turn allows for rapid S-phase entry. Silencing OTUD6B or LIN28B inhibits multiple myeloma outgrowth in vivo and high OTUD6B expression evolves in patients that progress to symptomatic multiple myeloma and results in an adverse outcome of the disease. Thus, we link proteolytic ubiquitylation with post-transcriptional regulation and nominate OTUD6B as a potential mediator of the MGUS-multiple myeloma transition, a central regulator of MYC, and an actionable vulnerability in multiple myeloma and other tumors with an activated OTUD6B-LIN28B axis

    Topographical and Anatomical Peculiarities of the Lower Urinary System in the Early Neonatal Period

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    The examination was conducted on 14 dead newborns (6 females and 8 males). The subject of the research was the anatomical features of the lower urinary tract in newborns.The objective of the research was to determine the features of microscopic anatomy and dynamics of the formation of the topographical and anatomical relationships between the vesicourethral segment and adjacent organs and structures in the early neonatal period of human ontogenesis, in particular, in newborns.Methods. The following complex of morphological examination was used: anthropometry to determine the age of the examined newborns; vascular injecting with further preparation using a microscope to investigate the features of blood supply to the vesicourethral segment; radiography to determine skeletotopy of the vesicourethral segment; macro- and microdissection to study anatomical interrelations between the components of the vesicourethral segment, their structure, shape, and position; morphometry to identify morphometric parameters of the vesicourethral segment; 3D reconstruction to determine spatial structure of the vesicourethral segment; statistical method to analyze and determine the probability of the deviations in the organometric parameters.Results. Characteristic anatomical signs of the vesicourethral segment in newborns, structural organization and chronological sequence of its topographical and anatomical relationships with adjacent pelvic organs and structures in dynamics were determined. Dependence of the vesicourethral segment size on age and gender was established. The obtained data on the anatomy and changes in the topographical and anatomical interrelations of the vesicourethral segment may be the morphological basis for the development of algorithms of antenatal diagnosis of congenital malformations of the vesicourethral segment, surgical correction of congenital abnormalities of the urinary tract in children of early age.Conclusions.The collection of firstly determined findings reveals patterns of morphogenesis of the vesicourethral segment in newborns
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