Peierls Instabilities in Quasi-One-Dimensional Quantum Double-Well Chains

Peierls-type instabilities in quarter-filled ($\bar{n}=1/2$) and half-filled ($\bar{n}=1$) quantum double-well hydrogen-bonded chain are investigated analytically in the framework of two-stage orientational-tunnelling model with additional inclusion of the interactions of protons with two different optical phonon branches. It is shown that when the energy of proton-phonon coupling becomes large, the system undergoes a transition to a various types of insulator states. The influence of two different transport amplitudes on ground states properties is studied. The results are compared with the pressure effect experimental investigations in superprotonic systems and hydrogen halides at low temperatures.Comment: 7 pages, RevTeX, 9 eps figure

Исследование динамических параметров техники плавания юных пловцов с использованием «АРТ–2»

Проведенное исследование юных пловцов обоего пола 12–16 лет позволило выявить их специальную подготовленность и дать практические рекомендации тренерам по индивидуальной коррекции тренировочного процесса. Ключевые слова: специальная физическая подготовленность, техника плавания, биологическая обратная связь. = The study of young swimmers of both sexes aged 12–16 revealed their specially trained and provide practical recommendations for the coaches of individual correction of the training process. Key words: special physical training, swimming techniques, biofeedback

Some aspects of the Liouville equation in mathematical physics and statistical mechanics

This paper presents some mathematical aspects of Classical Liouville theorem and we have noted some mathematical theorems about its initial value problem. Furthermore, we have implied on the formal frame work of Stochastic Liouville equation (SLE)

On a Theoretical Study of the Properties of Solutions of the Limit Problem for a Magnetically Noninsulated Diode

In this paper, we study the lower and upper bounds for solutions of the limit problem for the plane vacuum diode in the magnetic field in the statement by N. Ben Abdallah, P. Degond, and F. Mehats. This problem was finally set by physicists in the late 1980s and was extensively studied by numerous mathematicians in the 1990s.Досліджено нижні i вepxнi мєжі для розв'язків граничної задачi плоского вакуумного діода у магнітному полі у постановці Н. Бен Абдалла, П. Дегонда та Р. Мехаца. Ця задача була остаточно поставлена фізиками наприкінці 1980-х років i уважно досліджена багатьма математиками у 1990-х роках

Model of socio-economic factors in the spread of SARS-CoV-2 across Russian regions

The worldwide spread of a new infection SARS-CoV-2 makes relevant the analysis of the different factors that lead to the vulnerability of modern civilization to previously unknown diseases. In this regard, the development of mathematical models describing the evolution of epidemics like COVID-19 and the identification of socio-economic factors affecting the epidemiological situation in regions is an important research task. The paper proposes a probabilistic mathematical model for the spread of the COVID-19 epidemic, which allows to analyze the evolution of the main characteristics of the disease and to assess main factors influencing them. The study is based on the official statistical data on the spread of the COVID 19 presented on coronavirus sites in the Russian Federation and other countries, the Yandex Data Lens dataset service, as well as the data from the Federal State Statistics Service. In the research some data mining methods were used for evaluation the model’s parameters. The model equations allow to predict the evolution of the disease and estimate the confidence interval of such prognosis. We estimated the ratio of detected and hidden cases of the disease, the distribution of the disease’s duration probability and its average value for different regions. It has been mathematically proven that the vaccination is the necessary and sufficient condition of achievement a stationary stable state - the cessation of a pandemic. The regions of Russian Federation were clustered by the course of the disease COVID-19 on the base of k-means method. The analysis of the most important socio-economic factors affecting the epidemiological situation was provided separately for each cluster

Combined treatment of diffuse sclerosing osteomyelitis of mandible in children

Diffuse sclerosing osteomyelitis of the jaw (DSO) is a rare and poorly understood disease. Nowadays treatment protocols (steroid or painkillers, corticotomy) do not capable of to get good and stabile results or are associated with the development of potentially serious side effects. The treatment algorithm developed by us, including the course treatment with bisphosphonates, was well tolerated and capable of to get clinical and radiological remission in the case of previous decortication and antibacterial therapy was done. For these reasons, this treatment protocol is not without interest and need of further investigates. The study was approved by the Local Ethics Committee of Russian Children's Clinical Hospital. © 2019 by NMRC PHOI

Purification, cloning and characterisation of two forms of thermostable and highly active cellobiohydrolase I (Cel7A) produced by the industrial strain of Chrysosporium lucknowense

Two forms of cellobiohydrolase I (CBH I, Cel7A) were purified from the culture ultrafiltrate of a mutant strain of the fungus Chrysosporium lucknowense, an industrial producer of cellulases and hemicellulases. The enzymes had different molecular masses (52 and 65 kDa, SDS-PAGE data) but the same pI (4.5). Peptide sequencing showed that a single gene encodes both proteins. Both enzymes displayed maximum activity at pH 5.0-5.5; they had similar specific activities against soluble substrates. However, the 65 kDa CBH I was much more efficient in hydrolysis of Avicel and cotton cellulose, and its adsorption ability on Avicel was notably higher in comparison to the 52 kDa enzyme. Using the in-gel tryptic digestion followed by MALDI-TOF mass-spectrometry, it was shown that the 52 kDa enzyme represents the core catalytic module of the intact 65 kDa CBH I without a cellulose-binding module and major part of glycosylated linker. Both enzymes were stable at 50°C for 24 h. At higher temperature, the 65 kDa enzyme showed better thermostability: it retained >90% of activity after 7 h at 60°C and 50% of activity after 3 h at 65°C. The intact CBH I is also notably more thermostable than the Trichoderma reesei CBH I (by 6°C, the data of differential scanning microcalorimetry study). The cbh1 gene was cloned and then the amino acid sequence of Cel7A was deduced from the gene sequence. The enzyme had high degree of similarity (up to 74%) to family 7 cellobiohydrolases and lower degree of similarity (up to 41%) to family 7 endoglucanases. © 2004 Elsevier Inc. All rights reserved

Study of Dynamic Parameters of Swimming Technique Concerning Young Swimmers using «ART–2»

Проведенное исследование юных пловцов обоего пола 12–16 лет позволило выявить их специальную подготовленность и дать практические рекомендации тренерам по индивидуальной коррекции тренировочного процесса.The study of young swimmers of both sexes aged 12–16 revealed their specially trained and provide practical recommendations for the coaches of individual correction of the training process

Effect of pressure in the growth reactor on the properties of the active region in the InGaN/GaN light-emitting diodes

International audienceEffect of pressure in the reactor in the case of growth of active regions in the InGaN/GaN light-emitting diodes by the method of vapor-phase epitaxy from metalorganic compounds on their electroluminescent and structural properties has been studied. It is shown that, as pressure is increased, the InGaN layers become transformed from being continuous in the lateral direction to the layers of separate InGaN islands. This transformation affects both the emission efficiency and the dependence of efficiency on current