Structure and Multi-Center Bonding: From Atomic Clusters to Solid Phase Materials

The work presented in this dissertation has been focused on structure, stability, electronic properties, and chemical bonding of atomic clusters and solid-state compounds. The common thread was development of chemically intuitive models and theoretical methods capable of describing and interpreting bonding and hence, structures of these compounds. Understanding how interactions between atoms in sub-nano clusters and solid-state compounds of certain compositions determine their structures, physical properties, and reactivities is essential for rational design of new materials, catalysts, and molecular devices. A significant part of this work presents joint experimental and theoretical studies of doped boron clusters. Several projects on carbon- and aluminum-substituted boron clusters were aimed at establishing their structures, energetic and electronic properties, and understanding bonding interactions. The dissertation introduces a series of peculiar clusters containing transition metal atoms inside perfectly symmetrical boron rings. These clusters, featuring planar octa-, nona-, and decacoordinated transition metal atoms, were designed based on a simple chemical bonding model governing stabilities of such species. One of the most important parts of this dissertation deals with chemical bonding in the solid state. The Adaptive Natural Density Partitioning method previously developed by the Boldyrev group at Utah State University has proven very efficient for understanding chemical bonding in clusters and complex molecules. In this work, a periodic implementation of this method has been developed, yielding a new theoretical tool capable of interpretation of bonding in solid state in chemically intuitive terms of localized and multi-center bonds

THE PROBLEM OF INTERPRETATION OF PHYLOGENETIC TREES

Abstract. Phylogenetic algorithms have been used in a number of papers to describe the evolution of language families. In the paper the neighbor joining algorithm apply to the database of the Automated Similarity Judgment Program and results are compared with the common languages classification. A number of families have been considered in detail: North Caucasian languages, Turkic languages, Maya. In addition to recognized families, a hypothetical Nostratic macrofamily is also considered. When applying phylogenetic algorithms to databases, some errors occur. Possible causes of mistakes are analyzed, and a statement that mistakes are inevitable for phylogenetic algorithms is justified. The following main types of errors are identified. Languages in databases are represented as vectors of large dimension, while in the form of trees it is a one-dimensional structure. With decreasing dimension, the loss of information is mathematically unavoidable. Testing of one of the most popular phylogenetic algorithms – the algorithm of the neighbor joining – has been carried out, and it is shown that it gives an error in 13% of cases. Another source of error is the instability of phylogenetic algorithms – small (random) changes in the data can lead to a significant rearrangement of trees. A few recommendations on the methods of correct interpretation of results obtained via phylogenetic algorithms are proposed.Keywords: Phylogenetic Algorithm, Evolution Trees, ASJP Database, North-Caucasian languages, TurkicLanguages

Quantitative Analysis of Suffix Variability of Comparative Adjectives in Russian

There are two variants of the productive suffix of comparative adjectives used in modern Russian. They are a full two-syllable form and a reduced one-syllable suffix. Both variants are normative. However, they are slightly different in terms of stylistics. The suffix -ee makes the word sound neutral and the word with the suffix -ei sounds more colloquial. The article presents a quantitative study of variability of the suffixes of comparative adjectives and analyzes linguistic and extralinguistic factors that influence the frequency of the variants. The authors concluded that there is no previously anticipated influence of phonetic and morphological factors on the choice of the suffix of an adjective in a bookish speech

Dirac cones in two-dimensional borane

We introduce two-dimensional borane, a single-layered material of BH stoichiometry, with promising electronic properties. We show that, according to Density Functional Theory calculations, two-dimensional borane is semimetallic, with two symmetry-related Dirac cones meeting right at the Fermi energy $E_f$. The curvature of the cones is lower than in graphene, thus closer to the ideal linear dispersion. Its structure, formed by a puckered trigonal boron network with hydrogen atoms connected to each boron atom, can be understood as distorted, hydrogenated borophene (Science \textbf{350}, 1513 (2015)). Chemical bonding analysis reveals the boron layer in the network being bound by delocalized four-center two-electron ${\sigma}$ bonds. Finally, we suggest high-pressure could be a feasible route to synthesise two-dimensional borane.Comment: 5 pages, 3 figures, 1 tabl

FusorSV: an algorithm for optimally combining data from multiple structural variation detection methods.

Comprehensive and accurate identification of structural variations (SVs) from next generation sequencing data remains a major challenge. We develop FusorSV, which uses a data mining approach to assess performance and merge callsets from an ensemble of SV-calling algorithms. It includes a fusion model built using analysis of 27 deep-coverage human genomes from the 1000 Genomes Project. We identify 843 novel SV calls that were not reported by the 1000 Genomes Project for these 27 samples. Experimental validation of a subset of these calls yields a validation rate of 86.7%. FusorSV is available at https://github.com/TheJacksonLaboratory/SVE . Genome Biol 2018 Mar 20; 19(1):38

Multi-tissue integrative analysis of personal epigenomes

Evaluating the impact of genetic variants on transcriptional regulation is a central goal in biological science that has been constrained by reliance on a single reference genome. To address this, we constructed phased, diploid genomes for four cadaveric donors (using long-read sequencing) and systematically charted noncoding regulatory elements and transcriptional activity across more than 25 tissues from these donors. Integrative analysis revealed over a million variants with allele-specific activity, coordinated, locus-scale allelic imbalances, and structural variants impacting proximal chromatin structure. We relate the personal genome analysis to the ENCODE encyclopedia, annotating allele- and tissue-specific elements that are strongly enriched for variants impacting expression and disease phenotypes. These experimental and statistical approaches, and the corresponding EN-TEx resource, provide a framework for personalized functional genomics

Frequency of Verbal Forms and Language Standard

The article offers the description of a modern experiment, which gives the possibility of complex information extraction about the cognitive structure of the linguistic evolution of Language Standart (Norm). The study was conducted using the Google Books Corpus, which provides unprecedented opportunities for linguistic studies. The purpose of the experiment was to identify the patterns of competing forms evolution within the center of the verbal paradigm (3Sg and 3Pl) on the basis of the data concerning the frequency of their use. The study was conducted on the material of excess verb forms with the variability of a/o vowels in a root (обусловливать/обуславливать). The graphs for variable word form competition clearly illustrate that the process of norm change consists of stages, each of which has numerical characteristics of two competing word form use. The chronological frameworks for an inflectional model change are established with the accuracy of up to 10 years. The graphs obtained as the result of the experiment make it possible to conclude that almost half of the verbs were not variative, although they previously considered. During the discussion of the obtained empirical data, a conclusion is made about the morphemic structure of a word, in which a root vowel changes. Possessing the information about similar processes in other verb paradigms, researchers are able to predict a possible change of inflectional models in the future and, as a consequence, the fixing of a new norm in lexicographical, orthographic and orthoepic sources

Efficiency of Rejection of Adjacent-Channel Interference in the Wideband Radionavigation System

Приведены результаты разработки и моделирования компенсатора структурных помех для приемников широкополосной радионавигационной системы «Спрут». Имитационное моделирование компенсатора и корреляционного приемника, выполненное в среде Matlab- Simulink, свидетельствует, что предложенный адаптивный компенсатор обеспечивает высокую точность формирования копии структурной помехи. Предложенный адаптивный компенсатор структурной помехи позволяет повысить помехоустойчивость приемника шумоподобных сигналов с минимальной частотной манипуляцией: допустимый уровень структурной помехи с использованием адаптивного компенсатора составляет более 80 дБ.The article contains results of development and modeling the adjacent-channel interference compensator for receivers of wideband radio navigation system Sprut. Imitation modeling of the compensator and the correlation receiver was lead in CAE-system Matlab-Simulink and proves that the designed compensator provides high-accurate forming of the interferences copy. Designed adaptive adjacent-channel interference compensator allows to increase interference immunity of receiver of noise-like signals with minimum shift keying: Admissible level of adjacentchannel interference is more than 80 dB due to using the compensator

Efficiency of Rejection of Adjacent-Channel Interference in the Wideband Radionavigation System

Приведены результаты разработки и моделирования компенсатора структурных помех для приемников широкополосной радионавигационной системы «Спрут». Имитационное моделирование компенсатора и корреляционного приемника, выполненное в среде Matlab- Simulink, свидетельствует, что предложенный адаптивный компенсатор обеспечивает высокую точность формирования копии структурной помехи. Предложенный адаптивный компенсатор структурной помехи позволяет повысить помехоустойчивость приемника шумоподобных сигналов с минимальной частотной манипуляцией: допустимый уровень структурной помехи с использованием адаптивного компенсатора составляет более 80 дБ.The article contains results of development and modeling the adjacent-channel interference compensator for receivers of wideband radio navigation system Sprut. Imitation modeling of the compensator and the correlation receiver was lead in CAE-system Matlab-Simulink and proves that the designed compensator provides high-accurate forming of the interferences copy. Designed adaptive adjacent-channel interference compensator allows to increase interference immunity of receiver of noise-like signals with minimum shift keying: Admissible level of adjacentchannel interference is more than 80 dB due to using the compensator