Dual fermion method as a prototype of generic reference-system approach for correlated fermions

We present a purely diagrammatic derivation of the dual fermion scheme [Phys. Rev. B 77 (2008) 033101]. The derivation makes particularly clear that a similar scheme can be developed for an arbitrary reference system provided it has the same interaction term as the original system. Thereby no restrictions are imposed by the locality of the reference problem or by the nature of the original problem as a lattice one. We present new arguments in favour of keeping the dual denominator in the expression for the lattice self-energy independently of the truncation of the dual interaction. As an example we present the computational results for the half-filled 2D Hubbard model with the choice of a $2\times2$ plaquette with periodic boundary conditions as a reference system. We observe that obtained results are in a good agreement with numerically exact lattice quantum Monte Carlo data

Foam Metals High-Temperature Electrical Characteristics’ Investigation

In the work presented we have carried out experimental investigations of high- temperature electrophysical properties of foam metals. We have obtained data of foam nickel and foam copper resistivity and temperature coefficients of resistance (TCR) versus their plane deformation degree within the temperature range from 100 to 950 ºС

Effect of oxygen on the electrical conductivity of Pt-contacted α-Ga2O2/ε(κ)-Ga2O3 MSM structures on patterned sapphire substrates

Electrical conductivity and gas sensitivity of α-Ga2O2/ ε(κ)-Ga2O3 structures were measured for oxygen concentrations ranging from 2 % to 100 % and temperatures ranging from 25 °C to 220 °C. It was found that the oxygen sensitivity of the structures depended on the donor dopant concentration. The alpha -Ga _{2}O_{3}/arepsilon ( kappa )-Ga 2 O 3 structures doped with sim 1.5 imes 10^{17} cm −3 of Sn showed high sensitivity to O 2 in the temperature range from 180 °C to 220 °C and at the bias voltage below 7.5 V. This effect can be attributed to the chemisorption of oxygen molecules on the surface of structures, which reduces energy barriers between ε(κ)-Ga2O3 grains

Effect of omeprazole on patient-reported outcome measures in uninvestigated heartburn: a multi-country, multi-center observational study

Background: Heartburn occurs predominantly in the upper gastrointestinal tract and is associated with gastroesophageal reflux disease (GERD) and gastritis. Omeprazole is the most prescribed proton pump inhibitor class of medication to treat heartburn related clinical conditions. To compare the efficacy of omeprazole 40 mg (as a total daily dose) and 20 mg using patient-reported outcome measures (PROMs) in patients with heartburn due to various aetiologies like non-erosive reflux disease, GERD, gastritis, dyspepsia, functional heartburn, gastro-duodenal ulcer.Methods: Naïve patients presenting heartburn symptoms were treated with omeprazole. PROMs were assessed based on short-form-leeds dyspepsia questionnaires (SF-LDQ), work productivity activity impairment (WPAI), relief obtained using medication and, treatment satisfactory questionnaires (TSQ).Results: A total of 18,724 patients with heartburn (GERD and gastritis; n=10,509) were treated with omeprazole (Dr. Reddy’s omeprazole [DO]/generic omeprazole [GO]/branded omeprazole [BO]) 40 mg (as a total daily dose) and 20 mg. Statistical comparative analysis showed significant improvement with omeprazole 40 mg (as a total daily dose) compared to omeprazole 20 mg in SF-LDQ, relief obtained using medication among patients with heartburn. DO 20 mg showed a greater improvement under the ‘a lot’ and ‘complete’ relief category.Conclusions: Omeprazole 40 mg (as a total daily dose) presented better efficacy as compared to omeprazole 20 mg in patient reported outcomes. This study highlights omeprazole 40 mg as the preferred intervention for improving PROMs and quality of life in the treatment of heartburn related clinical conditions

HVPE growth of corundum-structured α-Ga2O3 on sapphire substrates with α-Cr2O3 buffer layer

Gallium oxide films were grown by HVPE on (0001) sapphire substrates with and without α-Cr2O3 buffer produced by RF magnetron sputtering. Deposition on bare sapphire substrates resulted in a mixture of α-Ga2O3 and ε-Ga2O3 phases with a dislocation density of about 2∙1010 cm-2. The insertion of α-Cr2O3 buffer layers resulted in phase-pure α-Ga2O3 films and a fourfold reduction of the dislocation density to 5∙109 cm-2

Интеграция науки, образования, права и этики в сфере генной, клеточной и тканевой биоветтехнологии

The paper analyzes the reasons of necessity in constant improving of ethic and legal space of educational and scientific activity in the modern world. The analysis is based on applying of new investigations in the field of biotechnology. The paper reveals problems appeared when studying reproduction and regeneration mechanisms. The authors demonstrate specific procedure of biological science development and enlighten the problems of interaction between “new possibilities” and archaic conditions contributing to their implementation. Problems of “new consciousness” and old views about human place in the world are shown as well. The article explains that gnosis dialectics of living matter leads to revolutions which demand strong changes in the life of modern society; when the modern society turns into society of knowledge and innovations and changes the subject of this process.В статье анализируются причины необходимости перманентного совершенствования этико-правового пространства образовательной и научной деятельности современного человека на примере новых направлений биотехнологии, а также освещаются проблемы изучения механизмов репродукции и регенерации. Показана специфика развития биологических наук, освещены проблемы взаимодействия «новых возможностей» и архаичных условий для их реализации, проблемы «нового сознания» и старых представлений о месте человека в мире. Обосновано, что диалектика познания живой материи неизбежно проводит к формированию революционных ситуаций, требующих кардинальных перемен в жизни современного информационного общества, превращения его в общество знаний и инноваций с соответствующим изменением субъекта этого процесса

Methods of Burning Solid Fuel Mixtures in Power Plants (Review)

В работе представлен один из наиболее доступных способов перехода к ресурсосберегающей и экологически безопасной выработке тепловой и электрической энергии угольными объектами теплоэнергетики, заключающийся в сжигании смесей топлив. Проведен обзор существующего опыта перевода действующего теплотехнического оборудования как в России, так и за рубежом, подробно описаны основные трудности в процессе сжигания твердотопливных смесей. Наиболее эффективные смеси по своим экологическим показателям получаются на основе угля и биомассы с ее добавлением по теплосодержанию не более 20 %. Горение остается одним из самых сложных и не исследованных процессов, а при совместном горении нескольких твердых топлив происходят дополнительные взаимодействия, которые влияют на основные характеристики горения, поэтому в работе отдельно рассмотрены методики исследований процесса горения и оборудование для проведения опытного сжигания твердотопливных смесейThe paper presents one of the most accessible ways to transition to resource-saving and environmentally safe generation of heat and electricity by coal-fired thermal power facilities, which consists in burning fuel mixtures. A review of the existing experience in the transfer of existing heat engineering equipment both in Russia and abroad is carried out, the main difficulties in the process of burning solid fuel mixtures are described in detail. The most effective mixtures in terms of their environmental performance are obtained on the basis of coal and biomass with its addition in terms of heat content of no more than 20 %. The combustion remains one of the most complex and unexplored processes, and during the joint combustion of several solid fuels, additional interactions occur that affect the main combustion characteristics, therefore, the paper separately considers the methods for studying the combustion process and equipment for experimental combustion of solid fuel mixture

Beringian Standstill and Spread of Native American Founders

Native Americans derive from a small number of Asian founders who likely arrived to the Americas via Beringia. However, additional details about the intial colonization of the Americas remain unclear. To investigate the pioneering phase in the Americas we analyzed a total of 623 complete mtDNAs from the Americas and Asia, including 20 new complete mtDNAs from the Americas and seven from Asia. This sequence data was used to direct high-resolution genotyping from 20 American and 26 Asian populations. Here we describe more genetic diversity within the founder population than was previously reported. The newly resolved phylogenetic structure suggests that ancestors of Native Americans paused when they reached Beringia, during which time New World founder lineages differentiated from their Asian sister-clades. This pause in movement was followed by a swift migration southward that distributed the founder types all the way to South America. The data also suggest more recent bi-directional gene flow between Siberia and the North American Arctic