Electrical resistivity of liquid CuSn, CuSnBi, CuSnBiIn, CuSnBiInCd alloys of equiatomic compositions

The resistivity of liquid CuSn,CuSnBi, CuSnBiIn, CuSnBiInCd alloys of equiatomic compositions are measured using the rotating magnetic field method to obtain information on their liquid structures. The alloys of equiatomic composition we considered as the high-entropy alloys. The results are discussed in the frame of a microheterogeneous structure of a metallic melt. A conclusion is made about the character of the modification of temperature dependence of the resistivity of liquid alloy due this microheterogeneous structure. All the investigated alloys demonstrated the change in the temperature coefficient of the resistivity for heating and cooling. These changes determined the temperature of destruction the microheterogeneous structure of a metallic melt (T∗). The value of temperature T∗ for all alloys was 1070 K (800 °C). The change in the temperature coefficient of the resistivity of the alloys on heating to 1070 K (800 °C) is interpreted using the Nagel-Tauc model. © 2019 Author(s)

New method of studying slow strange meson properties in nuclear matter

We suggest the new experimental method to explore the properties of slow strange mesons at normal nuclear matter density. We show that the $K^{+}$ and $K^{-}$ mesons with extremely small momenta relative to the surrounding medium rest frame can be produced in nucleus-nucleon collisions and their production cross sections are experimentally measurable. The experiments on study of the momentum dependence of meson-nuclear potentials are discussed.Comment: 4 pages, 2 figure

Volumes of polytopes in spaces of constant curvature

We overview the volume calculations for polyhedra in Euclidean, spherical and hyperbolic spaces. We prove the Sforza formula for the volume of an arbitrary tetrahedron in $H^3$ and $S^3$. We also present some results, which provide a solution for Seidel problem on the volume of non-Euclidean tetrahedron. Finally, we consider a convex hyperbolic quadrilateral inscribed in a circle, horocycle or one branch of equidistant curve. This is a natural hyperbolic analog of the cyclic quadrilateral in the Euclidean plane. We find a few versions of the Brahmagupta formula for the area of such quadrilateral. We also present a formula for the area of a hyperbolic trapezoid.Comment: 22 pages, 9 figures, 58 reference

DETECTION OF AUTOANTIBODIES RECOGNIZING CANCERRETINA ANTIGEN RECOVERIN IN BLOOD OF PATIENTS WITH NON-INVASIVE FOLLICULAR THYROID NEOPLASMS WITH PAPILLARY-LIKE NUCLEAR FEATURES (NIFTP)

Autoantibodies recognizing the cancer-retina autoantigen called recoverin (RCVRN-AutoAb) may serve as a highly specific biomarker of cancer-associated retinopathy. However, they may also be found in some cancer patients without clinical evidence of retinopathy. In the present study, dot-ELISA and Western blot assays were used to demonstrate the presence of circulating RCVRN-AutoAb in 4/7 (57%) of patients with recently recognized pathological entity, non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP); other thyroid tumors represented by follicular adenomas, and classical and follicular variants of papillary thyroid carcinomas, demonstrated low frequencies of RCVRN-AutoAb (0/15, 1/20 (5%) and 1/15 (7%), respectively), with no significant differences from healthy individuals (0/15). Our data implicate the circulating RCVRN-AutoAb as a potential biomarker of NIFTP capable of discrimination of this novel pathological entity from other thyroid tumors

Infrared absorption cross sections, and oscillator strengths of interstitial and substitutional double donors in silicon

Infrared absorption cross sections and corresponding oscillator strengths of several intracenter transitions of double donors in silicon, interstitial magnesium (Mg; group IIA) and substitutional chalcogens (Ch = S; Se; group VI), were determined for impurity densities in the ranges 1 × e14–1.6e15 atoms/cm3 for Mg and 2e13–2e16 atoms/cm3 for chalcogens. The concentrations of electrically active atomic and diatomic donor centers were derived from the Hall effect measurements. The experimental integrated cross sections were obtained from low-temperature impurity absorption spectra. The oscillator strengths of related donor transitions were derived and compared with those for shallow single donors in silicon, both determined experimentally and predicted theoretically. The transitions of oscillator strengths of double donors follow the decreasing trend with decreasing radius of donor ground states and increasing an impurity binding energy

Consensus position of endocrinologists and pathologists on coding causes of death in patients with diabetes mellitus (expert opinion)

Coding of the causes of death of patients with diabetes mellitus (DM) in the Russian Federation is one of the long-discussed problems, due to the comorbidity of diabetes and cardiovascular diseases (CVD) and a number of contradictions in the key regulatory documents regulating the statistics of mortality in this category of patients, which acquires particular relevance in the context of the coronavirus pandemic, due to its negative impact on the outcomes of the course of COVID-19 and mortality risks. In pursuance of the decisions of the Minutes of the meeting of the working group under the project committee of the National Project «Health» on identifying patterns in the formation of mortality rates of the population dated January 20, 2021 No. 1, chaired by Deputy Prime Minister of the Russian Federation T.A. Golikova, experts of two directions - endocrinology and pathological anatomy, prepared a Draft of agreed recommendations on the Rules for coding the causes of death of patients with diabetes, causing the greatest problems in terms of the use of ICD-10 when choosing the initial cause of death, including in the case of death from CVD and COVID-19

Thermal Activation of Valley-Orbit States of Neutral Magnesium in Silicon

Interstitial magnesium acts as a moderately deep double donor in silicon, and is relatively easily introduced by diffusion. Unlike the case of the chalcogen double donors, parameters of the even-parity valley-orbit excited states 1s(T2) and 1s(E) have remained elusive. Here we report on further study of these states in neutral magnesium through temperature dependence absorption measurements. The results demonstrate thermal activation from the ground state 1s(A1) to the valley-orbit states, as observed by transitions from the thermally populated levels to the odd-parity states 2p0 and 2p±. Analysis of the data makes it possible to determine the thermal activation energies of transitions from the donor ground state to 1s(T2) and 1s(E) levels, as well as the binding energies of an electron with the valley-orbit excited states. Keywords: magnesium impurity in silicon, deep center, optical spectroscopy

The Large Enriched Germanium Experiment for Neutrinoless Double Beta Decay (LEGEND)

The observation of neutrinoless double-beta decay (0${\nu}{\beta}{\beta}$) would show that lepton number is violated, reveal that neutrinos are Majorana particles, and provide information on neutrino mass. A discovery-capable experiment covering the inverted ordering region, with effective Majorana neutrino masses of 15 - 50 meV, will require a tonne-scale experiment with excellent energy resolution and extremely low backgrounds, at the level of $\sim$0.1 count /(FWHM$\cdot$t$\cdot$yr) in the region of the signal. The current generation $^{76}$Ge experiments GERDA and the MAJORANA DEMONSTRATOR utilizing high purity Germanium detectors with an intrinsic energy resolution of 0.12%, have achieved the lowest backgrounds by over an order of magnitude in the 0${\nu}{\beta}{\beta}$ signal region of all 0${\nu}{\beta}{\beta}$ experiments. Building on this success, the LEGEND collaboration has been formed to pursue a tonne-scale $^{76}$Ge experiment. The collaboration aims to develop a phased 0${\nu}{\beta}{\beta}$ experimental program with discovery potential at a half-life approaching or at $10^{28}$ years, using existing resources as appropriate to expedite physics results.Comment: Proceedings of the MEDEX'17 meeting (Prague, May 29 - June 2, 2017