Quasiparticle Interference on the Surface of Topological Crystalline Insulator Pb(1-x)Sn(x)Se

Topological crystalline insulators represent a novel topological phase of matter in which the surface states are protected by discrete point group-symmetries of the underlying lattice. Rock-salt lead-tin-selenide alloy is one possible realization of this phase which undergoes a topological phase transition upon changing the lead content. We used scanning tunneling microscopy (STM) and angle resolved photoemission spectroscopy (ARPES) to probe the surface states on (001) Pb$_{1-x}$Sn$_{x}$Se in the topologically non-trivial (x=0.23) and topologically trivial (x=0) phases. We observed quasiparticle interference with STM on the surface of the topological crystalline insulator and demonstrated that the measured interference can be understood from ARPES studies and a simple band structure model. Furthermore, our findings support the fact that Pb$_{0.77}$Sn$_{0.23}$Se and PbSe have different topological nature.Comment: 5 pages, 4 figure

Dust-free starburst galaxies at redshifts z>10z>10

One of the most distant galaxies GN-z11 was formed when the Universe was $\le$ 400 Myr old, and it displays a burst-like star formation rate \sim 25~\msun yr$^{-1}$ with a metallicity $Z\sim 0.2\pm 0.1Z_\odot$. It resembles $z=2-3$ galaxies (at ``cosmic noon") except for the fact that the measured reddening $E(B-V)=0.01\pm 0.01$ indicates the presence of little or no dust. This marked absence of dust hints towards violent dynamical events that destroy or evacuate dust along with gas out of the galaxy on a relatively short time scale and make it transparent. We apply a 3D numerical model to infer possible physical characteristics of these events. We demonstrate that the energetics of the observed star formation rate is sufficient to tear apart the dusty veil on time scales of $20-25$ Myr. This can explain the apparent lack of evolution of UV luminosity function of galaxies between and $z\ge 10$ and $z\sim 7$, by compensating for the lower galaxy masses at higher redshift by the absence of dust. We show, however, that this is a temporary phenomenon and soon after the last of the supernovae explosions have taken place, the expanding shell shrinks and obscures the galaxy on time scales of $\approx 5-8$ Myr.Comment: submitted to MNRAS Letters, 5 pages, 4 figure

Current Trends in Global Supply Chain Management Investment Policy

Abstract- To achieve the Sustainable Development Goals of the world economy, significant financial resources and global supply chain are needed. Priority issues are related to the use of investment resources. Almost all sectors of the economy have a real need for investment. Domestic investments is not enough for countries to implement effective structural policies and upgrade fixed assets. They are forced to attract foreign investment. The annual requirements for international investment reach several trillion US dollars. However, foreign investors are in no hurry to expand investments in the economy of foreign countries. Moreover, in 2017-2019 there is a decrease in global direct foreign investment flows. This is largely due to a noticeable reduction in US investment in the economies of the European Union and China as a result of the tightening of the American protectionism policy pursued by the D. Trump administration and the US Federal Reserve to strengthen regulation of foreign companies in the US market. A decrease in the level of international investment under the worsening business climate in the world leads to the increased competition between countries for attracting foreign investment

Влияние психотропных лекарственных средств на спонтанную поведенческую активность белых крыс

Установлено, что использование нейролептиков в условиях экспериментального психоза сопровождалось более выраженным, чем у интактных животных, понижением подвижности, опытнического поведения, эмоциональности. В отличие от этого, действие атипичного нейролептика сульпирида характеризовалось угнетением тревожности при повышении подвижности. Ноотропные препараты приводили к усилению подвижности и эмоциональной активности. Установлены фармакологические эффекты нейролептиков, антидепрессантов и ноотропных препаратов, которые могут применяться в клинической практике для оптимизации лечения больных с психическими расстройствами, в частности шизофренией

Quasiparticle interference on the surface of the topological crystalline insulator Pb_(1−x)Sn_xSe

Topological crystalline insulators represent a novel topological phase of matter in which the surface states are protected by discrete point group symmetries of the underlying lattice. Rock-salt lead-tin-selenide alloy is one possible realization of this phase, which undergoes a topological phase transition upon changing the lead content. We used scanning tunneling microscopy (STM) and angle resolved photoemission spectroscopy (ARPES) to probe the surface states on (001) Pb_(1−x)Sn_xSe in the topologically nontrivial (x=0.23) and topologically trivial (x=0) phases. We observed quasiparticle interference with STM on the surface of the topological crystalline insulator and demonstrated that the measured interference can be understood from ARPES studies and a simple band structure model. Furthermore, our findings support the fact that Pb_(0.77)Sn_(0.23)Se and PbSe have different topological nature

Logistic outsourcing in pharmacy. the theory and practice

Today, the introduction and application of a logistics approach to resource management allows pharmaceutical companies to increase their social, environmental and economic efficiency. The article is aimed to research the essence of the concept, types and party of logistic outsourcing in practical pharmacy. To reach the aimreview of foreign and domestic scientific sources and the existing legal framework of Ukraine on this issue have been analyzed. Investigation methods were bibliographic and analytical ones. The results of these studies indicate the today outsourcing is one of the main logistics strategies of domestic pharmaceutical companies, which is actively used in the sphere of IT-technologies and warehouse services. At the same time for ensuring high-quality providing outsourcing services, a legal and regulatory framework is needed that standardizes the interaction between firm customer and the outsourcer, also the development of standards for the provision of services of a certain type of outsourcing. Wide introduction of logistics outsourcing, as a modern form of optimization of logistics business processes, requires the formation of professional competence among future pharmacists in pharmaceutical logistics, its tools and strategies, i.e. training of competitive professionals capable of working in various directions of practical pharmacy. Introduction of the topic «Logistic outsourcing in practical pharmacy» in the educational process of students of pharmaceutical faculties (university), pharmacists-interns and pharmacists at the postgraduate level of training is necessary. It will improve the theoretical and practical training of future specialist pharmaceutists and will allow them to apply the knowledge which would be gained in the future in logistics outsourcing in the activities of pharmaceutical companies

Features of coagulopathy and systemic inflammation in patients after COVID-19 infection

The aim: To determine the peculiarities of laboratory data concerning blood coagulation and systemic inflammation in COVID-19 patients in three months after discharge and recovery. The state of coagulation, anticoagulation, and fibrinolytic systems, as well as their prognostic value having been well studied in hospitalized COVID-19 patients, their state three months after hospitalization, are not yet well understood. Materials and methods: Methods of randomization, anthropometry, ECG, standard clinical blood testing, immunoenzymometry, immunoanalysis, and primary statistical analysis were used in the study. Anthropometric measurements of patients (n=20), blood samples, blood serum samples, urine samples, and statistical data were the materials of the study. Results: Indices of coagulation and systemic inflammation in studied patients after COVID-19 were obtained (PTT, s ; PATPT, s; Fibrinogen, g/L; Platelets ×109 /L; PCT, ng/mL; DD, µg/L; СRP, mg/L; IL -6, pg/mL; IL -10, pg/mL; Cortisol (nM/L); CIC (IU/mL); Ig A (g/L). Conclusions: Summing up the results obtained, it is possible to assert micro- and macro-vascular thromboses to be common in COVID-19 cases; they are associated with poor prognosis for diseased patients and are not completely investigated; the role of thromboses in COVID-19 course and complications are to be studied as well as the strategies of fibrinolytic therapies for such condition are to be justified. The presence of specific rheological and serological changes in patients even three months after surviving COVID-19 needs further study to understand the necessity of anti-thrombolytic drug uptake for a relatively long time

On Nanomodification of Coating Obtained by Laser Cladding of Composite Powder 12NVK-01

The results of an experimental study of the effect of nanomodifying additives on the structure and mechanical properties of a multilayer coating during laser surfacing of a composite powder with a strengthening phase are presented. As a surfacing material, nickel powder 12NVK -01 with a strengthening phase of tungsten carbide was used, and as a modifying additive was a mixture of nanosized refractory powders of titanium nitride and yttrium oxide clad with iron and chromium. It is established that the deposited coating represents a complex system of phases formed during the melting and interaction of the chemical elements of the substrate and the melted powder mixture. The main component of the coating is the combination of nickel with iron and chromium of the type Ni3(Fe,Cr). In the melting process, a partial decomposition of the strengthening phase occurs, depending on the concentration of the nanomodifier. In the case considered, the optimum amount of the modifying additive providing the maximum hardness and wear resistance increase of the composite coatings of the Ni-Cr-B-Si-Fe / WC system is 0.1% by mass of the refractory TiN+Y[2]O[3] nanopowder additive in the composite material

On Nanomodification of Coating Obtained by Laser Cladding of Composite Powder 12NVK-01

The results of an experimental study of the effect of nanomodifying additives on the structure and mechanical properties of a multilayer coating during laser surfacing of a composite powder with a strengthening phase are presented. As a surfacing material, nickel powder 12NVK -01 with a strengthening phase of tungsten carbide was used, and as a modifying additive was a mixture of nanosized refractory powders of titanium nitride and yttrium oxide clad with iron and chromium. It is established that the deposited coating represents a complex system of phases formed during the melting and interaction of the chemical elements of the substrate and the melted powder mixture. The main component of the coating is the combination of nickel with iron and chromium of the type Ni3(Fe,Cr). In the melting process, a partial decomposition of the strengthening phase occurs, depending on the concentration of the nanomodifier. In the case considered, the optimum amount of the modifying additive providing the maximum hardness and wear resistance increase of the composite coatings of the Ni-Cr-B-Si-Fe / WC system is 0.1% by mass of the refractory TiN+Y[2]O[3] nanopowder additive in the composite material