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For the first time, the distribution of rare earth elements (REE) has been studied in detail for a number of coal facilities (30 deposits, 650 samples of coal and 210 samples of carbonaceous rocks). The ubiquitous presence of elevated concentrations of REE in coals has been noted. The REE mineral cluster in coals includes the association: ash content of coals – SiO2 – K2O – Al2o3 – TiO2 – Sc – Y – Dy – Ho – Er – Tm – Yb – Lu, and the association La – Ce – Pr – Nd – Sm – Eu – Gd – Tb. The presence of these elements of the mineral part of the coals is preferably in the composition of phosphate minerals – monazite and apatite (according to electron microscopy with microanalysis, the correlation of REE with P2o5). The content of individual REE in humic acids isolated from coals and fractions of coals of different densities has been studied. The specific role of organic matter(s) in the concentration of REE, their presence in the humus component of S and in low-ash coals is shown. Selective accumulation (fractionation) of heavy REE by organic matter has been experimentally established for the first time. Two genetic types of REE mineralization have been identified in coals: mainly terrigenous (hydrogenic) and tufogenic. The increased concentrations of REE in coals are due to the influence of the petrofund. The deposits were ranked according to the degree of prospects for REE based on an assessment of the resource potential of associated REE in the coals of the studied brown coal deposits. REE raw materials (lanthanides in coal ash) differ significantly from traditional types of rare earths ores by an incomparably large relative amount of heavy REE (on average 3–4 times), sometimes reaching 46% of the total REE content. Thus, coal ash is a unique non–traditional source of heavy lanthanides – more rare, valuable and expensive. The coals of the studied deposits should be considered as associated raw materials for rare earths.

Introduction. Medical compression stockings are one of the main methods in a conservative strategy for the treatment of chronic vein diseases as well as for adjuvant treatment after superficial venous interventions. however, compliance to this treatment is low.Objective. To evaluate patient satisfaction with medical compression knitwear therapy in a short-term follow-up.Materials and мethods. The study included 150 patients of both sexes aged 42 ± 8.3 years. Endovenous laser obliteration combined with mini-phlebectomy and/or sclerotherapy for varicose veins was performed. All patients after the surgery wore compression stockings of compression class 2 with a recommended wearing period of 14 days. At the control visit at the end of the follow-up period all patients were asked to complete a satisfaction survey with a specially prepared questionnaire including 7 questions.Results and discussion. No significant adverse events and complications related to either the invasive intervention or the compression therapy were observed during the follow-up period. There were no abnormalities such as compression sensations or changes in blood flow under the knitwear. The compression was totally adequate, with no areas of over- and/or under-compression. All respondents felt that the knitwear was well anchored to the leg and no slipping or twisting due to the wide elastic band with droplet silicone. In addition to all of the above, the patients noted that the knitwear offered to them in the study had good tactile properties: it was soft and pleasant to the skin. According to the survey, the average score for all questions was 9.5 (QR 8-10).Conclusion. Elastic compression is an effective and safe means of preventing adverse events, complications and pain in patients after superficial varicose veins surgery. Additional consumer properties of medical compression knitwear can significantly influence patients’ compliance and therefore the effectiveness of treatment.

The extraordinary properties of the Kitaev model have motivated an intense search for new physics in materials that combine geometrical and bond frustration. In this Letter, we employ inelastic neutron scattering, spin wave theory, and exact diagonalization to study the spin dynamics in the perfect triangular-lattice antiferromagnet (TLAF) CsCeSe2. This material orders into a stripe phase, which is demonstrated to arise as a consequence of the off-diagonal bond-dependent terms in the spin Hamiltonian. By studying the spin dynamics at intermediate fields, we identify an interaction between the single-magnon state and the two-magnon continuum that causes decay of coherent magnon excitations, level repulsion, and transfer of spectral weight to the continuum that are controlled by the strength of the magnetic field. Our results provide a microscopic mechanism for the stabilization of the stripe phase in TLAF and show how complex many-body physics can be present in the spin dynamics in a magnet with strong Kitaev coupling even in an ordered ground state.

The two-dimensional triangular-lattice antiferromagnet (TLAF) is a textbook example of frustrated magnetic systems. Despite its simplicity, the TLAF model exhibits a highly rich and complex magnetic phase diagram, featuring numerous distinct ground states that can be stabilized through frustrated next-nearest-neighbor couplings or anisotropy. In this paper, we report low-temperature magnetic properties of the TLAF material CsCeSe2. The inelastic neutron scattering (INS) together with specific heat measurements and density functional theory calculations of crystalline electric field suggest that the ground state of Ce ions is a Kramers doublet with strong easy-plane anisotropy. Elastic neutron scattering measurements demonstrate the presence of stripe-yz magnetic order that develops below TN=0.35K, with the zero-field ordered moment of mCe≈0.65μB. Application of magnetic field first increases the ordering temperature by about 20% at the intermediate field region and eventually suppresses the stripe order in favor of the field-polarized ferromagnetic state via a continuous quantum phase transition (QPT). The field-induced response demonstrates sizable anisotropy for different in-plane directions, Ba and Ba, which indicates the presence of bond-dependent coupling in the spin Hamiltonian. We further show theoretically that the presence of anisotropic bond-dependent interactions can change the universality class of QPT for Ba and Ba.

This article is devoted to the analysis of restructuring in the Russian production sector basing on the worldwide experience of innovative industrial policy with the focus on the role of the government in this process. While the author in the article identifies de- and re-industrialization trends, cluster systems organization as well as development of national innovation systems (NIS) as crucial processes in the global industry great attention is paid to the role of the state in these processes. International practice in developed countries shows that the state plays key role in industrialization process acting as a brainchild in setting target values for R&D industrial expansion implementing institutional, infrastructure, preferential as well as tax relief forms of support. Major advanced economies devote considerable attention to creation of supportive environment for industrial development, including implementation of national innovation systems (NIS) as well as elaboration of the institutional infrastructure industry development programs. Global market industrial trends analysis shows that production sector together with its innovative development will remain a major priority and a driving force in global economic growth. Taking into account present situation of the Russian economy which can be described as critical, time factor is considered to be of great importance, making it necessary to adopt accelerated development model in the Russian economy reforms. A key question to consider is what actions should be adopted by the government to ensure acceleration in economic development of the country.

In this work, we study effects of magnon interactions in the excitation spectrum of CoNb2O6 in the quantum paramagnetic phase in transverse field, where the 1/S spin-wave theory exhibits unphysical divergences at the critical field. We propose a self-consistent Hartree-Fock approach that eliminates such unphysical singularities while preserving the integrity of the singular threshold phenomena of magnon decay and spectrum renormalization that are present in both theory and experiment. With the microscopic parameters adopted from previous studies, this method yields a close quantitative agreement with the available experimental data for CoNb2O6 in the relevant regime. Insights into the general structure of the spin-anisotropic model of CoNb2O6 and related zigzag chain materials are also provided and a discussion of the effects of additional longitudinal field on the spectrum is given.

Using large-scale density-matrix renormalzation group calculations and minimally augmented spin-wave theory, we demonstrate that the phase diagram of the quantum S=12J1-J3 ferro-antiferromagnetic model on the honeycomb lattice differs dramatically from the classical one. It hosts the double-zigzag and Ising-z phases as unexpected intermediaries between ferromagnetic and zigzag states that are also extended beyond their classical regions of stability. In broad agreement with quantum order-by-disorder arguments, these collinear phases replace the classical spiral state.

The OBJECTIVE was to study the short-term results of surgical treatment of patients with brachial artery injury in peacetime upper limb injury.METHODS AND MATERIALS. This study presents the short-term results of surgical treatment of 61 patients with brachial artery injury in peacetime upper limb injury. The study included 33 patients who were admitted to the City Hospital of St. Martyr Elizabeth in St. Petersburg from 2011 to 2022 and 28 patients who were admitted to Hospitals in the Leningrad Region from 2017 to 2022.RESULTS. All 61 patients underwent emergency surgery: autovenous prosthetics of the brachial artery was performed in 46 patients, an end-to-end anastomosis was formed in 10 patients, and a lateral suture was applied to 5 patients. In the early postoperative period, there were 3 thrombosis of the reconstruction zone, 1 amputation of a limb, 1 fatal outcome from severe blood loss.CONCLUSION. Upper limb injury with brachial artery injury without specialized assistance can lead to disability and even death of a patient, therefore requires emergency intervention by a vascular surgeon to stop bleeding, restore the main blood flow and stop limb ischemia.

We provide strong evidence of the spin-nematic state in a paradigmatic ferro-antiferromagnetic J_{1}-J_{2} model using analytical and density-matrix renormalization group methods. In zero field, the attraction of spin-flip pairs leads to a first-order transition and no nematic state, while pair repulsion at larger J_{2} stabilizes the nematic phase in a narrow region near the pair-condensation field. A devil's staircase of multipair condensates is conjectured for weak pair attraction. A suppression of the spin-flip gap by many-body effects leads to an order-of-magnitude contraction of the nematic phase compared to naïve expectations. The proposed phase diagram should be broadly valid.

The Kitaev model, a honeycomb network of spins with bond-dependent anisotropic interactions, is a rare example of a system with a quantum spin liquid ground state. Although most Kitaev model candidate materials eventually order magnetically due to additional non-Kitaev interactions, their bond-dependent anisotropy manifests in unusual spin dynamics. Recent research suggests that bond-dependent anisotropy can stabilize exotic magnetic phases on the geometrically frustrated triangular lattice. Unfortunately, few materials have been identified with simultaneous geometric frustration and bond-dependent anisotropy. Here, we report a frustrated triangular lattice with bond-dependent anisotropy in the cobalt-based van der Waals antiferromagnet CoI2. Momentum and energy-resolved inelastic neutron scattering measurements show substantial magnon decay and level repulsion. A thorough examination of excitations in both the paramagnetic and magnetically ordered states demonstrates that the bond-dependent anisotropy is the origin of the spiral order and the magnon decay found in CoI2. Our results provide the basis for future studies of the interplay between Kitaev magnetism and geometric frustration.

We provide analytical and numerical insights into the phase diagram and other properties of the extended Kitaev-Heisenberg model on the honeycomb lattice in the easy-plane limit, in which interactions are only between spin components that belong to the plane of magnetic ions. This parameter subspace allows for a much-needed systematic quantitative investigation of spin excitations in the ordered phases and of their generic features. Specifically, we demonstrate that in this limit one can consistently take into account magnon interactions in both zero-field zigzag and field-polarized phases. For the nominally polarized phase, we propose a regularization of the unphysical divergences that occur at the critical field and are plaguing the 1/S approximation in this class of models. For the explored parameter subspace, all symmetry-allowed terms of the standard parametrization of the extended Kitaev-Heisenberg model, such as K, J, and Γ, are significant, making the offered consideration relevant to a much wider parameter space. The dynamical structure factor near the paramagnetic critical point illustrates this relevance by showing features that are reminiscent of the ones observed in α-RuCl3, underscoring that they are not unique and should be common to a wide range of parameters of the model and, by extension, to other materials.