FD-method for solving the nonlinear Klein–Gordon equation

We propose a functional discrete method for solving the Goursat problem for the nonlinear Klein–Gordon equation. Sufficient conditions for the superexponential convergence of this method are established. The obtained theoretical results are illustrated by a numerical example.Запропоновано функцiонально-дискретний метод розв’язування задачi Гурса для нелiнiйного рiвняння Кляйна – Гордона. Отримано достатнi умови, якi забезпечують суперекспоненцiальну швидкiсть збiжностi методу. Одержанi теоретичнi результати проiлюстровано на числовому прикладi

Manganese Content Control in Weld Metal During MAG Welding

The influence of the welding current and method of gas shielding in MAG welding on the content of manganese is considered in the paper. Results of study of the welded specimens of steels 45 when applying welding wire of different formulas and different types of gas shielding (traditional shielding and double-jet shielding) are given. It is found that in MAG welding the value of the welding current and the speed of the gas flow from the welding nozzle have a considerable impact on the chemical composition of the weld metal. The consumable electrode welding under double-jet gas shielding provides the directed gas-dynamics in the welding area and enables controlling the electrode metal transfer and the chemical composition of a weld

Terahertz transverse-magnetic-polarized waves localized on layered superconductor defect in photonic crystals

We theoretically study eigenstates of electromagnetic field inside a one-dimensional photonic crystal containing a defect slab of layered superconductor. Basing on the transfer matrix formalism along with the electrodynamics of Josephson plasma, we obtain the dispersion relations describing the THz electromagnetic modes localized on defect. We consider both symmetric and antisymmetric configuration of defect in photonic crystal. The comparison of the dispersion spectra of the localized states for the layered-superconducting defect and the pure insulating defect reveals the features of the studied system.Теоретически исследованы собственные состояния электромагнитного поля в одномерном фотонном кристалле, содержащем дефектную пластину из слоистого сверхпроводника. Основываясь на методе трансфер-матрицы, с использованием электродинамики джозефсоновской плазмы, получены дисперсионные соотношения, описывающие терагерцевые электромагнитные моды, локализованные на дефекте. Рассмотрены симметричная и антисимметричная конфигурации дефекта в фотонном кристалле. Сравнение дисперсионных спектров локализованных состояний для сверхпроводящего и диэлектрического дефектов позволяет выявить особенности изучаемой системы.Теоретично вивчені власні стани електромагнітного поля в одновимірному фотонному кристалі, що містить дефектну пластину з шаруватого надпровідника. Ґрунтуючись на методі трансфер-матриці, з використанням електродинаміки джозефсонівської плазми, отримані дисперсійні співвідношення, які описують терагерцові електромагнітні моди, що локалізовані на дефекті. Розглядаються симетрична і антисиметричну конфігурації дефекту в фотонному кристалі. Порівняння дисперсійних спектрів локалізованих станів для надпровідного і діелектричного дефектів дозволило виявити особливості системи, що досліджується

A Laser Frequency Comb System for Absolute Calibration of the VTT Echelle Spectrograph

A wavelength calibration system based on a laser frequency comb (LFC) was developed in a co-operation between the Kiepenheuer-Institut f\"ur Sonnenphysik, Freiburg, Germany and the Max-Planck-Institut f\"ur Quantenoptik, Garching, Germany for permanent installation at the German Vacuum Tower Telescope (VTT) on Tenerife, Canary Islands. The system was installed successfully in October 2011. By simultaneously recording the spectra from the Sun and the LFC, for each exposure a calibration curve can be derived from the known frequencies of the comb modes that is suitable for absolute calibration at the meters per second level. We briefly summarize some topics in solar physics that benefit from absolute spectroscopy and point out the advantages of LFC compared to traditional calibration techniques. We also sketch the basic setup of the VTT calibration system and its integration with the existing echelle spectrograph.Comment: 9 pages, 2 figures; Solar Physics 277 (2012

Особенности микробиоты у пациентов с воспалительными заболеваниями кишечника (проспективное исследование)

Background. The intestinal microbiota, on the one hand, protects a person from pathogens, on the other hand, it itself may be one of the triggers and/or mediators of progression in inflammatory bowel diseases. Inflammatory bowel disease (IBD) predominantly affects young people of working age. It noted a steady increase in the incidence of IBD in recent decades throughout the world and in Russia. Inflammatory bowel diseases significantly affect quality of life and lead to complications of having to perform surgery, which significantly reduces the quality of life. Aims of the study was to investigate the composition of the microbiota of the colon, the search features of the microbial spectrum of patients with inflammatory bowel disease patients compared with control patients. Materials and methods. A prospective study was carried out between patients with inflammatory bowel disease and patients without inflammatory bowel disease for the period 20182019. The study included 157 IBD patients and 150 patients without IBD. All patients studied stool, which have been subjected to microbiological and metagenomic study. Results. Most often, facultative anaerobic microorganisms were present in the stool of patients with IBD (in 60%, 103109 CFU/g) and in patients without IBD (69%, 103109 CFU/g), the share of gram-negative bacteria accounted for 52%, in mostly represented by bacilli belonging to the order Enterobacteriales, only 7% of isolated gram-negative facultative aerobic microorganisms were gram-negative non-fermenting bacteria represented by 5 genera: Acinetobacter, Burkholderia, Pseudomonas, Stenotrophomonas, Ralstonia. Gram-positive facultative anaerobic microorganisms in 89% were represented by cocci of the genus Enterococcus, Streptococcus, Staphylococcus, Micrococcus, Gemella, Globicatella, Granulicatella. Conclusions. According to the results of our study, special attention should be paid to the presence of rare microaerophilic and obligate anaerobic microorganisms in the fecal microbiota of patients with IBD (Arcobacter butzleri, Gardnerella vaginalis, Aromatoleum aromaticum, Terrisporobacter glycolicus (Clostridium glycolicum), Solobacterium moorei, Alloscardovia omnicolens, Fusobacterium nucleatum, Fusobacterium ulcerans, Dialister micraerophilus), that have not been isolated from patients without IBD. A timely adequate assessment of the composition and functional characteristics of the microbiota in terms of key biomarkers will make it possible to carry out targeted diagnostics and prevention of the immediate and long-term consequences of inflammatory bowel diseases.Обоснование. Микробиота кишечника, с одной стороны, защищает человека от патогенов, а с другой сама может являться одним из триггеров и/или медиаторов прогрессирования при воспалительных заболеваниях кишечника (ВЗК). ВЗК поражают преимущественно лиц молодого трудоспособного возраста. Отмечается неуклонный рост заболеваемости ВЗК в последние десятилетия во всем мире и в России. ВЗК существенно влияют на качество жизни, а осложнения приводят к необходимости выполнения хирургических вмешательств, что значительно снижает качество жизни. Цель исследования изучение состава микробиоты толстой кишки, поиск особенностей микробного спектра у пациентов с воспалительными заболеваниями кишечника по сравнению с пациентами контрольной группы. Методы. Выполнено проспективное исследование пациентов с ВЗК и пациентов, находящихся на лечении в колопроктологическом стационаре, без воспалительных заболеваний кишечника за 20182019 гг. В исследование были включены 157 пациентов ВЗК и 150 пациентов без ВЗК. У всех пациентов исследовались биообразцы стула, которые были подвергнуты микробиологическому и метагеномному исследованию. Результаты. Наиболее часто в просветных фекалиях пациентов с ВЗК (в 60% случаев в титре 103109 КОЕ/г) и пациентов без ВЗК (69% случаев в титре 103109 КОЕ/г) присутствовали факультативно анаэробные микроорганизмы, среди которых на долю грамнегативных бактерий приходилось 52% случаев, в большей части представленных бациллами, относящимися к порядку Enterobacteriales, только 7% изолированных грамнегативных факультативно аэробных микроорганизмов являлись грамнегативными неферментирующими бактериями (ГОНФБ), представленными пятью родами: Acinetobacter, Burkholderia, Pseudomonas, Stenotrophomonas, Ralstonia. Грампозитивные факультативно анаэробные микроорганизмы в 89% случаев были представлены кокками родов Enterococcus, Streptococcus, Staphylococcus, Micrococcus, Gemella, Globicatella, Granulicatella. По результатам нашего исследования следует обратить особое внимание на присутствие в фекальной микробиоте пациентов с ВЗК редких микроаэрофильных и облигатно анаэробных микроорганизмов Arcobacter butzleri, Gardnerella vaginalis, Aromatoleum aromaticum, Terrisporobacter glycolicus (Clostridium glycolicum), Solobacterium moorei, Alloscardovia omnicolens, Fusobacterium nucleatum, Fusobacterium ulcerans и Dialister micraerophilus, которые не были изолированы от пациентов без ВЗК. Заключение. Своевременная адекватная оценка состава и функциональных характеристик микробиоты по показателям ключевых биомаркеров позволит проводить направленную диагностику и профилактику ближайших и отдаленных последствий воспалительных заболеваний кишечника

Biomonitoring of selected persistent organic pollutants (PCDD/Fs, PCBs and PBDEs) in Finnish and Russian terrestrial and aquatic animal species

Background: The Finnish and Russian animal species (semi-domesticated reindeer, Finnish wild moose, Baltic grey seal and Baltic herring) samples were biomonitored in terrestrial and aquatic environments for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenylethers (PBDEs). Results: Grey seal (Halichoerus grypus) was clearly the most contaminated species. The mean PBDE concentration in grey seal was 115 ng/g fat, and the highest WHO-PCDD/F-PCB-TEQ (toxic equivalent set by WHO) was 327 pg/g fat. In Finnish, reindeer WHO-PCDD/F-TEQ varied from 0.92 pg/g fat in muscle to 90.8 pg/g fat in liver. WHO-PCDD/F-TEQ in moose liver samples was in the range of 0.7–4.26 pg/g fat, and WHO-PCB-TEQ in the range of 0.42–3.34 pg/g fat. Overall moose had clearly lower PCDD/F and DL-PCB concentrations in their liver than reindeer. Conclusions: Terrestrial animals generally had low POP concentrations, but in reindeer liver dioxin levels were quite high. All Finnish and Russian reindeer liver

Active Brownian Particles. From Individual to Collective Stochastic Dynamics

We review theoretical models of individual motility as well as collective dynamics and pattern formation of active particles. We focus on simple models of active dynamics with a particular emphasis on nonlinear and stochastic dynamics of such self-propelled entities in the framework of statistical mechanics. Examples of such active units in complex physico-chemical and biological systems are chemically powered nano-rods, localized patterns in reaction-diffusion system, motile cells or macroscopic animals. Based on the description of individual motion of point-like active particles by stochastic differential equations, we discuss different velocity-dependent friction functions, the impact of various types of fluctuations and calculate characteristic observables such as stationary velocity distributions or diffusion coefficients. Finally, we consider not only the free and confined individual active dynamics but also different types of interaction between active particles. The resulting collective dynamical behavior of large assemblies and aggregates of active units is discussed and an overview over some recent results on spatiotemporal pattern formation in such systems is given.Comment: 161 pages, Review, Eur Phys J Special-Topics, accepte

Integrating sequence and array data to create an improved 1000 Genomes Project haplotype reference panel

A major use of the 1000 Genomes Project (1000GP) data is genotype imputation in genome-wide association studies (GWAS). Here we develop a method to estimate haplotypes from low-coverage sequencing data that can take advantage of single-nucleotide polymorphism (SNP) microarray genotypes on the same samples. First the SNP array data are phased to build a backbone (or 'scaffold') of haplotypes across each chromosome. We then phase the sequence data 'onto' this haplotype scaffold. This approach can take advantage of relatedness between sequenced and non-sequenced samples to improve accuracy. We use this method to create a new 1000GP haplotype reference set for use by the human genetic community. Using a set of validation genotypes at SNP and bi-allelic indels we show that these haplotypes have lower genotype discordance and improved imputation performance into downstream GWAS samples, especially at low-frequency variants. © 2014 Macmillan Publishers Limited. All rights reserved

Narrow-pass-band filters based on binary superlattices with strong impedance contrast

The photonic band structure and transmission coefficient of a dielectric bilayer periodic array with strong impedance contrast are calculated and analyzed. It is found that the photonic band structure has broad pass bands and very narrow gaps. However, because of the strong impedance contrast and the use of lossless dielectric layers, the transmission spectrum exhibits sharp peaks inside the pass bands. The remarkable properties of the superlattice can be used for the fabrication of narrow-pass-band filters