A solution to the problem of clustered objects compact partitioning

The urgency of the study consists in the fact that an object arrangement topology of a distributed system is often nonuniform. Objects can be placed at different distances from each other, thus forming clusters. That is why solving the problem of compact partitioning into sets containing thousands of objects requires the most effective way to a better use of natural structuring of objects that form clusters. The aim of the study is the development of methods of compact partitioning of sets of objects presented as clusters. The research methods are based on applied theories of sets, theory of compact sets and compact partitions, and linear programming methods with Boolean variables. As a result, the paper offers the method necessary to analyze composition and content of clusters. It also evaluates cluster compactness, which results in the decision to include clusters into the sets of partitions. It addresses the problem of optimizing the rearrangement of objects between compact sets that form clusters, which is based on the criteria of maximizing the total compactness of sets. The problem is formulated in the class of objectives of linear programming methods with Boolean variables. It introduces the example of object rearrangement

Quantum spin chain as a potential realization of the Nersesyan-Tsvelik model

It is well established that long-range magnetic order is suppressed in magnetic systems whose interactions are low-dimensional. The prototypical example is the S-1/2 Heisenberg antiferromagnetic chain (S-1/2 HAFC) whose ground state is quantum critical. In real S-1/2 HAFC compounds interchain coupling induces long-range magnetic order although with a suppressed ordered moment and reduced N\'eel temperature compared to the Curie-Weiss temperature. Recently, it was suggested that order can also be suppressed if the interchain interactions are frustrated, as for the Nersesyan-Tsvelik model. Here, we study the new S-1/2 HAFC, (NO)[Cu(NO3)3]. This material shows extreme suppression of order which furthermore is incommensurate revealing the presence of frustration consistent with the Nersesyan-Tsvelik model

Monitoring of the Effectiveness of Public Relations to Optimize the Website of the Ministry of the Russian Federation for Affairs for Civil Defence, Emergencies and Elimination of Consequences of Natural Disasters

Development of websites as an important component of PR-collaboration to achieve their audiences in today's information environment has become one of the defining criteria of perception of the effectiveness of state institutions activities. The study presents the initiation of market research to identify advantageous features, tools, and internet communication technologies in the activities of the five public institutions of Rostov region. Data analysis served as the justification for proposals of the expert group on benchmarking for the website of the Southern Regional Center of the Ministry of the Russian Federation for Civil Defense, Emergencies and Elimination of Consequences of Natural Disasters (SRC MES of Russia). Keywords: expert survey method, website optimization, online communications, public relations JEL Classifications: A10, 010, Z1

Electronic structure and magnetic properties of the strong-rung spin-1 ladder compound Rb3 Ni2(NO3)7

Rb3Ni2(NO3)7 was obtained by crystallization from anhydrous nitric acid solution of rubidium nitrate and nickel nitrate hexahydrate. The crystal structure determined on single crystals implies isolated spin-1 two-leg ladders of Ni2+ ions connected by (NO3)- groups as basic elements. Magnetic susceptibility, specific heat in magnetic fields up to 9 T, magnetization, and high-frequency electron spin resonance studies performed on powder samples show the absence of long-range magnetic order at T≥2 K. Electronic structure calculations and the detailed analysis of the experimental data enable quantitative estimates of the relevant parameters of the S=1 ladders in Rb3Ni2(NO3)7. The rung coupling J1=10.16 K, the leg coupling J2=1.5 K, and the Ising-type anisotropy |A|=8.6 K are obtained. The scenario of a valence-bond solidlike quantum ground state realized in the two-leg Ni2+ ladders is further corroborated by model simulations of the magnetic susceptibility. © 2018 American Physical Society

Транслокаторный белок TSPO 18 кДа и его лиганды: перспективный подход к созданию новых нейропсихотропных средств

Resume. It is 41 years in 2018 since Braestrup and Squires opened translocator protein 18 kDa TSPO, known until 2006 as the peripheral benzodiazepine receptor (PBR). The functions of this receptor, which is one of the most important component of the outer mitochondrial membrane, have been studied in detail during this time. One of the key functions of TSPO is the transfer of cholesterol from the outer to the inner membrane of mitochondria, which is the limiting step in the synthesis of neurosteroids. In addition, TSPO is involved in porphyrin transport, mitochondrial respiration, the opening of mitochondrial pores, apoptosis and cell proliferation. This review presents the modern views on the structure of TSPO, the mechanism of it participation in neurosteroidogenesis and the endogenous and synthetic ligands of TSPO. Particular emphasis is placed on the analysis of approaches to the design of synthetic ligands and their neuropsychotropic activity in vitro and in vivo. This review demonstrates the prospects of new neuropsychotic drugs design among TSPO ligands.В 2018 году исполняется 41 год с момента открытия Браэстрап и Сквирес транслокаторного белка TSPO 18 кДа, известного до 2006 года под названием «периферический бензодиазепиновый рецептор» (PBR). За это время были подробно исследованы функции этого рецептора, который является важнейшим компонентом наружной мембраны митохондрий. Одной из ключевых функций TSPO является перенос холестерина от внешней к внутренней мембране митохондрий, что является лимитирующей стадией в синтезе нейростероидов. Кроме того, TSPO задействован в транспорте порфиринов, митохондриальном дыхании, открытии митохондриальных пор, апоптозе и пролиферации клеток. Настоящий обзор посвящён рассмотрению современных представлений о структуре TSPO, механизме его участия в нейростероидогенезе и эндогенных и синтетических лигандах TSPO. Особый акцент сделан на анализе подходов к дизайну синтетических лигандов и их нейропсихотропной активности in vitro и in vivo. Представленный обзор демонстрирует перспективность конструирования новых нейропсихотропных средств в ряду лигандов TSPO

Co(NO3)2 as an Inverted Umbrella-type Chiral Noncoplanar Ferrimagnet

The low-dimensional magnetic systems tend to reveal exotic spin-liquid ground states or form peculiar types of long-range order. Among systems of vivid interest are those characterized by the triangular motif in two dimensions. The realization of either ordered or disordered ground state in triangular, honeycomb, or kagome lattices is dictated by the competition of exchange interactions, also being sensitive to anisotropy and the spin value of magnetic ions. While the low-spin Heisenberg systems may arrive to a spin-liquid long-range entangled quantum state with emergent gauge structures, the high-spin Ising systems may establish the rigid noncollinear structures. Here, we present the case of chiral noncoplanar inverted umbrella-type ferrimagnet formed in cobalt nitrate Co(NO3)2 below TC=3K with the comparable spin and orbital contributions to the total magnetic moment. © 2020 American Physical Society.This work has been supported by Russian Scientific Foundation, Grant No. 19-42-02010 and by Russian Foundation for Basic Research (RFBR) Grants No. 18-52-52005, No. 18-502-12022, No. 19-02-00015, and No. 19-03-01059. We acknowledge support by the Russian Ministry of Science and Higher Education, Contracts No. 02.A03.21.0004, No. 02.A03.21.0006, and No. 02.A03.21.0011. O.V.M. and A.N.V. acknowledge support by NUST “MISiS,” Grant No. K2-2020-008. We acknowledge the support of Hochfeld Magnetlabor Dresden at Helmholtz Zentrum Dresden Rossendorf, member of the European Magnetic Field Laboratory (EMFL). B.L. acknowledges the support of DFG through Project No. B06 of SFB 1143 (ID No. 247310070). J.-Y.L. was supported by Taiwan MOST Grant No. 107-2923-M-009-001-MY3 and by the center for Emergent Functional Matter Science of NCTU from the Featured Areas Research Center program within the framework of the Higher education Sprout Project by the Ministry of Education (MOE) in Taiwan. M.A.-H. acknowledges the support from the Swedish Research Council Grant No. (VR) 2018-05339. I.V.S. was supported by Program AAAA-A18-118020190095-4 (Quantum)