Natural study of marginal array rock`s stress state

Safety working out water-soluble ore fields in many ways depends on the stability of chamber development system`s elements. To monitor the interchamber pillars` status a method of experimental and theoretical evaluation of the geomechanical processes taking place in the array was developed, the essence of which lies in the meaningful results interpretation of mechanical characteristics and the stress state experimental studies of load-carrying structures by mathematical modeling methods. The article describes the method of estimating the marginal rock array`s stress state. The tension control was made using an acoustic memory effect. The measurements were performed in the wells with the help of a Goodman hydraulic jack. Its feature is the ability to create a load on the borehole array in the same plane, that allows to evaluate the stress magnitude in various directions. During the loading of the measuring borehole walls there is a discontinuous increase in the activity of acoustic emission. The pressure, which is logged in the hydraulic system, was taken at the level of the natural stresses acting in the marginal array. As a result of complex laboratory and field studies methodological features of stress analysis were identified using memory effects in salt rocks of the Verkhnekamskoye potash salt deposit. The experimental data analysis showed that in the “fresh” interchamber pillars a bearing pressure maximum is located near the contour of exposure and in 1.8-2.0 times higher than the load of of the overlying rocks` weight (gH). In the central part of the pillar the vertical stress level is 1.25-1.4 gH. With the increase in pillars` service life the marginal array`s stresses magnitude declines to the stress level of the overlying rocks weight. The horizontal stress increases with moving from the pillar contour and are approximately 60-70% of the vertical. These instrumental measurements results are a source data for assessing the long-term sustainability of interchamber pillars in sylvinite layers mining

Photolysis of Fluorinated Graphites with Embedded Acetonitrile Using a White-Beam Synchrotron Radiation

Fluorinated graphitic layers with good mechanical and chemical stability, polar C–F bonds, and tunable bandgap are attractive for a variety of applications. In this work, we investigated the photolysis of fluorinated graphites with interlayer embedded acetonitrile, which is the simplest representative of the acetonitrile-containing photosensitizing family. The samples were continuously illuminated in situ with high-brightness non-monochromatized synchrotron radiation. Changes in the compositions of the samples were monitored using X-ray photoelectron spectroscopy and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. The NEXAFS N K-edge spectra showed that acetonitrile dissociates to form HCN and N2 molecules after exposure to the white beam for 2 s, and the latter molecules completely disappear after exposure for 200 s. The original composition of fluorinated matrices CF0.3 and CF0.5 is changed to CF0.10 and GF0.17, respectively. The highly fluorinated layers lose fluorine atoms together with carbon neighbors, creating atomic vacancies. The edges of vacancies are terminated with the nitrogen atoms and form pyridinic and pyrrolic units. Our in situ studies show that the photolysis products of acetonitrile depend on the photon irradiation duration and composition of the initial CFx matrix. The obtained results evaluate the radiation damage of the acetonitrile-intercalated fluorinated graphites and the opportunities to synthesize nitrogen-doped graphene materials

Polymorphism of inflammatory system genes in the pathogenesis of rheumatic heart disease

Aim. To assess the contribution of polymorphic variants of inflammatory response genes to the predisposition to rheumatic heart disease.Material and methods. Using real-time polymerase chain reaction, we analyzed the prevalence of 18 polymorphic variants of 8 genes involved in the inflammatory process in 251 patients with rheumatic heart disease and 300 healthy donors.Results. We found that homozygous TT genotypes of rs1800871 (IL10) (p=0,02) and TT rs1800872 (IL10) polymorphisms (p=0,027), as well as TT genotypes of CRP gene (rs1205) (p=0,015) and GG genotypes of rs375947 (IL12RB) (p=0,037) are "risky" and associated with the development of rheumatic heart disease.Conclusion. Associations of polymorphic variants rs1800871 and rs1800872 of the IL10 gene, rs1205 of the CRP gene, and rs375947 of the IL12RB gene can be an important link in the pathogenesis of rheumatic heart disease and can later be used as biological markers for a personalized assessment of the disease risk

Differential Diagnosis of New-Onset Pulmonary Ground Glass Changes During the COVID-19 Pandemic: a Case Report

The paper describes a clinical case of hypersensitivity pneumonitis in a young patient during the COVID-19 pandemic when the patient having complaints of dyspnea and interstitial lung changes as ground glass opacity was initially unambiguously diagnosed with viral COVID-related bilateral pneumonia. The chief computed tomography manifestations in the lung were infiltrative inflammatory changes as numerous areas of predominantly interstitial infiltration by the type of ground glass, with consolidation areas and reticular changes, varying in extent, peripheral localization, mainly in the lower lobes and with the 25–50% involvement of the right and left lung parenchyma. The diagnosis of hypersensitivity pneumonitis was confirmed by cytological and histological examinations of the biopsy material obtained during bronchoscopy using a set of biopsies and endobronchial cryobiopsy.This clinical case demonstrates that the chest computed tomography detection of pulmonary ground glasstype changes is a reason for further patient examinations and requires morphological verification of the diagnosis, since the cost of a diagnostic error is the life of a patient

Normal families of functions and groups of pseudoconformal diffeomorphisms of quaternion and octonion variables

This paper is devoted to the specific class of pseudoconformal mappings of quaternion and octonion variables. Normal families of functions are defined and investigated. Four criteria of a family being normal are proven. Then groups of pseudoconformal diffeomorphisms of quaternion and octonion manifolds are investigated. It is proven, that they are finite dimensional Lie groups for compact manifolds. Their examples are given. Many charactersitic features are found in comparison with commutative geometry over $\bf R$ or $\bf C$.Comment: 55 pages, 53 reference

Locally Anisotropic Structures and Nonlinear Connections in Einstein and Gauge Gravity

We analyze local anisotropies induced by anholonomic frames and associated nonlinear connections in general relativity and extensions to affine Poincare and de Sitter gauge gravity and different types of Kaluza-Klein theories. We construct some new classes of cosmological solutions of gravitational field equations describing Friedmann-Robertson-Walker like universes with rotation (ellongated and flattened) ellipsoidal or torus symmetry.Comment: 37 page

Controlling pyridinic, pyrrolic, graphitic, and molecular nitrogen in multi-wall carbon nanotubes using precursors with different N/C ratios in aerosol assisted chemical vapor deposition

Nitrogen-containing multi-wall carbon nanotubes (N-MWCNTs) were synthesized using aerosol assisted chemical vapor deposition (CVD) techniques in conjunction with benzylamine:ferrocene or acetonitrile: ferrocene mixtures. Different amounts of toluene were added to these mixtures in order to change the N/C ratio of the feedstock. X-ray photoelectron and near-edge X-ray absorption fine structure spectroscopy detected pyridinic, pyrrolic, graphitic, and molecular nitrogen forms in the N-MWCNT samples. Analysis of the spectral data indicated that whilst the nature of the nitrogen-containing precursor has little effect on the concentrations of the different forms of nitrogen in N-MWCNTs, the N/C ratio in the feedstock appeared to be the determining factor. When the N/C ratio was lower than ca. 0.01, all four forms existed in equal concentrations, for N/C ratios above 0.01, graphitic and molecular nitrogen were dominant. Furthermore, higher concentrations of pyridinic nitrogen in the outer shells and N2 molecules in the core of the as-produced N-MWCNTs suggest that the precursors were decomposed into individual atoms, which interacted with the catalyst surface to form CN and NH species or in fact diffused through the bulk of the catalyst particles. These findings are important for a better understanding of possible growth mechanisms for heteroatom-containing carbon nanotubes (CNTs) and therefore paving the way for controlling the spatial distribution of foreign elements in the CNTs using CVD processes

Measurement of CNGS muon neutrino speed with Borexino

We have measured the speed of muon neutrinos with the Borexino detector using short-bunch CNGS beams. The final result for the difference in time-of-flight between a =17 GeV muon neutrino and a particle moving at the speed of light in vacuum is {\delta}t = 0.8 \pm 0.7stat \pm 2.9sys ns, well consistent with zero.Comment: 6 pages, 5 figure

Edge state magnetism in zigzag-interfaced graphene via spin susceptibility measurements

Development of graphene spintronic devices relies on transforming it into a material with a spin order. Attempts to make graphene magnetic by introducing zigzag edge states have failed due to energetically unstable structure of torn zigzag edges. Here, we report on the formation of nanoridges, i.e., stable crystallographically oriented fluorine monoatomic chains, and provide experimental evidence for strongly coupled magnetic states at the graphene-fluorographene interfaces. From the first principle calculations, the spins at the localized edge states are ferromagnetically ordered within each of the zigzag interface whereas the spin interaction across a nanoridge is antiferromagnetic. Magnetic susceptibility data agree with this physical picture and exhibit behaviour typical of quantum spin-ladder system with ferromagnetic legs and antiferromagnetic rungs. The exchange coupling constant along the rungs is measured to be 450 K. The coupling is strong enough to consider graphene with fluorine nanoridges as a candidate for a room temperature spintronics material

Оценка экспрессии провоспалительных цитокинов в гладкомышечных клетках коронарной артерии, экспонированных мутагеном алкилирующего механизма действия

Background. It is known that DNA damage in smooth muscle cells can trigger their clonal expansion and transformation into foam cells. Thus, the study of the molecular genetic mechanisms of the vascular smooth muscle cells response to genotoxic exposure is important and relevant in the context of an in-depth understanding of atherogenesis.Aim. To study mRNA level and concentration of proinflammatory cytokines IL6 and IL8 in the human coronary artery smooth muscle cells exposed to alkylating mutagen.Methods. Gene expression signature of studied cytokines in the human coronary artery smooth muscle cells was accessed by quantitative polymerase chain reaction in the two timepoints – immediately after six-hour exposure to mitomycin C (point 1) and after six-hour exposure to mitomycin C followed by 24 hours of cells being cultivated on mitomycin C-free cell growth medium (point 2). Smooth muscle cells cultured according to the above scheme without genotoxin were used as controls. HPRT1, GAPDH and B2M were used as the reference genes. Gene expression level was calculated by ΔCt method. IL6 and IL8 concentration was evaluated in the culture media in points 1 and 2 by enzyme-linked immunosorbent assay. Statistical analysis was performed in GraphPad Prism 9 software.Results. Immediately after mutagenic exposure (point 1) we discovered no significant changes in the expression level of IL6 and IL8 in the mitomycin C exposed smooth muscle cells compared to controls. Removal of mutagen increased expression of IL6 and IL8 in the experimental group (0,36- and 0,67-fold, respectively). At the same time, we discovered no significant differences in the studied cytokines concentration in the culture medium of mutagen-exposed cells compared to the nonexposed controls.Conclusion. Genotoxic stress in human coronary artery smooth muscle cells exposed to alkylating mutagen (mitomycin C) leads to differential expression but not secretion of proinflammatory cytokines IL6 and IL8. Thus, exposure of smooth muscle cells to mitomycin C do not trigger their proinflammatory phenotype. Актуальность. Известно, что повреждение ДНК гладкомышечных клеток может быть триггером их клональной экспансии и трансформации в пенистые клетки. Таким образом, изучение молекулярно-генетических механизмов ответа гладкомышечных клеток сосудов на генотоксическое воздействие представляется важным и актуальным в контексте углубленного понимания механизмов атерогенеза.Цель. Изучить характер изменения уровня мРНК и концентрации провоспалительных цитокинов IL6 и IL8 в гладкомышечных клетках коронарной артерии человека, культивируемых в условиях генотоксической нагрузки.Материалы и методы. Уровень генной экспрессии изучаемых цитокинов в гладкомышечных клетках коронарной артерии человека оценивали с помощью количественной полимеразной цепной реакции в двух временных точках – непосредственно после 6 ч экспозиции клеток митомицином С (точка 1) и после 6 ч экспозиции мутагеном с последующими 24 ч культивирования клеток в чистой культуральной среде (точка 2). Контролем служили гладкомышечные клетки, культивированные по вышеуказанной схеме без генотоксической нагрузки. В качестве референсных генов использовали HPRT1, GAPDH и B2M. Уровень экспрессии генов интереса рассчитывали по методу ΔCt. Концентрацию IL6 и IL8 в культуральной среде определяли с помощью иммуноферментного анализа в точках 1 и 2. Статистический анализ полученных результатов проводили в программе GraphPad Prism 9.Результаты. Непосредственно после мутагенного воздействия (точка 1) не выявлено изменения уровня экспрессии генов IL6 и IL8 в гладкомышечных клетках, экспонированных митомицином С, по сравнению с неэкспонированным контролем. После удаления из культур мутагена в экспериментальной группе отмечено снижение уровня мРНК генов IL6 и IL8 по сравнению с контролем (кратность изменения экспрессии составила 0,36 и 0,67 соответственно). При этом достоверных различий концентрации изученных цитокинов в культуральной среде гладкомышечных клеток, экспонированных митомицином С, по сравнению с контролем не выявлено.Заключение. Генотоксический стресс в гладкомышечных клетках коронарной артерии человека, вызванный алкилирующим мутагеном митомицином С, приводит к изменению профиля генной экспрессии, но не концентрации провоспалительных цитокинов IL6 и IL8. Таким образом, воздействие митомицина С на гладкомышечные клетки не приводит к формированию ими провоспалительного фенотипа