Polarizable molecular interactions in condensed phase and their equivalent nonpolarizable models

Earlier, using phenomenological approach, we showed that in some cases polarizable models of condensed phase systems can be reduced to nonpolarizable equivalent models with scaled charges. Examples of such systems include ionic liquids, TIPnP-type models of water, protein force fields, and others, where interactions and dynamics of inherently polarizable species can be accurately described by nonpolarizable models. To describe electrostatic interactions, the effective charges of simple ionic liquids are obtained by scaling the actual charges of ions by a factor of 1/sqrt(eps_el), which is due to electronic polarization screening effect; the scaling factor of neutral species is more complicated. Here, using several theoretical models, we examine how exactly the scaling factors appear in theory, and how, and under what conditions, polarizable Hamiltonians are reduced to nonpolarizable ones. These models allow one to trace the origin of the scaling factors, determine their values, and obtain important insights on the nature of polarizable interactions in condensed matter systems.Comment: 43 pages, 3 figure

Ore-forming Сonditions of the Blagodat Gold Deposit in the Riphean Metamorphic Rocks of the Yenisey Ridge According to Geochemical and Isotopic Data

Neodymium and strontium isotopic composition and rare earth elements (REE) distribution pattern have been determined in whole rocks and minerals were separated from host metamorphic rocks and disseminated sulfide ores of the Blagodat gold deposit. Isotopic data are given to construct few isochrones that could be reflected an age of main stages of metamorphic and metasomatic alteration in rocks varieties during a successive accumulation of gold in structural traps. The significant temporal range in the forming of the studied rocks can be interpreted as an evidence of multi-stage tectonic destruction accompanying with trust-folding processes, shear deformations and development of local fracture zones that had place from the Late Riphean to Middle Paleozoic time. According to isotopic data basic ore-forming processes were realized in the relatively narrow interval from 690 to 750 Ma that correspond to a beginning of continental rifting on the western margin of Siberian craton. Chemistry and trace element distribution are closed for host and auriferous schists and mainly showed differences in the composition initial sedimentary units. The middle negative value εNd (from -14 to -16) and very high positive value εSr (from +570 to +725) are mostly corresponded to that of upper continental crust matter. The role of synchronic granite intrusions in the studied area can be only estimated due to a generation of thermal energy and crustal fluids

Investigation of high conductivity area at the interface between Ba0.8Sr0.2TiO3 and LaMnO3 after effect of electric field on Ba0.8Sr0.2TiO3 ferroelectric film

The reported study was funded by Russian Scientific Foundation, research project No. 18-12-00260

Effect of magnetic field on high conductivity area at the interface of heterostructure Ba0.8Sr0.2TiO3/LaMnO3

The reported study was funded by Russian Scientific Foundation, research project No. 18-12-00260

One year follow-up of the multi-centre European PARTNER transcatheter heart valve study

BackgroundTranscatheter aortic valve implantation (TAVI) has emerged as a new therapeutic option in high-risk patients with severe aortic stenosis.AimsPARTNER EU is the first study to evaluate prospectively the procedural and mid-term outcomes of transfemoral (TF) or transapical (TA) implantation of the Edwards SAPIEN® valve involving a multi-disciplinary approach.Methods and resultsPrimary safety endpoints were 30 days and 6 months mortality. Primary efficacy endpoints were haemodynamic and functional improvement at 12 months. One hundred and thirty patients (61 TF, 69 TA), aged 82.1 ± 5.5 years were included. TA patients had higher logistic EuroSCORE (33.8 vs. 25.7, P <0.0005) and more peripheral disease (49.3 vs. 16.4, P< 0.0001). Procedures were aborted in four TA (5.8) and six TF cases (9.8). Valve implantation was successful in the remaining patients in 95.4 and 96.4, respectively. Thirty days and 6 months survival were 81.2 and 58.0 (TA) and 91.8 and 90.2 (TF). In both groups, mean aortic gradient decreased from 46.9 ± 18.1 to 10.9 ± 5.4 mmHg 6 months post-TAVI. In total, 78.1 and 84.8 of patients experienced significant improvement in New York Heart Association (NYHA) class, whereas 73.9 and 72.7 had improved Kansas City Cardiomyopathy Questionnaire (KCCQ) scores in TA and TF cohorts, respectively.ConclusionThis first team-based multi-centre European TAVI registry shows promising results in high-risk patients treated by TF or TA delivery. Survival rates differ significantly between TF and TA groups and probably reflect the higher risk profile of the TA cohort. Optimal patient screening, approach selection, and device refinement may improve outcomes

Structural, electronic and magnetic properties of ferroelectric/dielectric heterostructures

The reported study was funded by Russian Scientific Foundation according to the research project No. 18-12-00260. The work is partially performed according to the Russian Government Program of Competitive Growth of Kazan Federal University

Study of omega-meson production in pp collisions at ANKE

The production of omega-mesons in the pp->pp omega reaction has been investigated with the COSY-ANKE spectrometer for excess energies of 60 and 92MeV by detecting the two final protons and reconstructing their missing mass. The large multipion background was subtracted using an event-by-event transformation of the proton momenta between the two energies. Differential distributions and total cross sections were obtained after careful studies of possible systematic uncertainties in the overall ANKE acceptance. The results are compared with the predictions of theoretical models. Combined with data on the phi-meson, a more refined estimate is made of the Okubo-Zweig-Iizuka rule violation in the phi/omega production ratio.Comment: 10 pages, 9 figures, version 1, submitted to EPJ-

Оптимизация хирургической тактики лечения локализованных форм рака толстой кишки (обзор литературы)

Malignant tumors have long occupied a special place in medicine and many researchers in different areas focused their attention on these disorders. Particular attention should be paid to gastrointestinal tumors with colon cancer being the most common among them. Moreover, the incidence of colon cancer is constantly growing.Despite the extensive experience in surgical treatment for colon cancer, we are still in search for new optimal methods that can increase overall and relapse-free survival without increasing the incidence of intra- and post-operative complications that are always associated with the volume of surgery.Recently, there has been a stable trend towards organ-sparing techniques. Segmental resections have become widely used in patients with localized cancer of the left colon and are now considered as an alternative to traditional left hemicolectomy. These two techniques demonstrated no significant differences in long-term outcomes. Then segmental resections became widely used in patients with localized tumors of the right colon and middle third of the transverse colon. These surgeries demonstrated their efficacy and good long-term outcomes.As for caecal cancer, the literature on this subject is too scant to make any conclusions about the rationality and feasibility of ileocecal resections. This implies that the utility of the method and its potential implications should be evaluated in further studies, including prospective ones that will compare both short-term and long-term outcomes. This literature review analyzes anatomical and physiological characteristics of right and left colon tumors, outlines generally accepted standards of lymphadenectomy, and summarizes the information on novel surgical techniques for colorectal cancer.Злокачественные новообразования на протяжении многих десятилетий занимают особое место в медицине, фокусируя на себе внимание исследователей разных специальностей. Самое пристальное внимание стоит уделить опухолям желудочно-кишечного тракта, среди которых рак ободочной кишки стабильно занимает 1-е место, имея тенденцию к ежегодному росту показателя заболеваемости.Несмотря на многолетний накопленный опыт хирургического лечения злокачественных новообразований толстой кишки, сохраняется необходимость поиска новых оптимальных методов лечения, способных повысить показатели общей и безрецидивной выживаемости, при этом учитывая вероятность осложнений, возникающих в интра- и послеоперационном периоде, которые неизменно связаны с объемом выполняемых оперативных вмешательств.Со временем в клинической практике хирургов наметилась тенденция к выбору органосохраняющих методик. Сегментарные резекции нашли широкое применение при локализованных формах рака левого изгиба ободочной кишки, став альтернативой общепринятой методике левосторонней гемиколэктомии. Опыт их применения не показал статистически значимых различий в отношении отдаленных онкологических результатов. Впоследствии сегментарные резекции начали активно проводиться при локализованных формах рака правого изгиба и средней трети поперечной ободочной кишки, доказывая свою целесообразность и демонстрируя отсутствие статистически значимых различий в долгосрочных исходах лечения.Что касается рака слепой кишки, то представленных на сегодняшний день данных литературы и описанных научных исследований недостаточно, чтобы уверенно говорить о рациональности и обоснованности широкого применения илеоцекальных резекций. Из чего следует, что возможность использования, а также потенциальная область приложения данной методики требуют дальнейшего изучения, в том числе в рамках проспективных исследований, с последующим сравнительным анализом как непосредственных, так и отдаленных результатов лечения. В представленном обзоре литературы были проанализированы анатомо-физиологические особенности правосторонней и левосторонней локализации опухолей ободочной кишки, изложены общепринятые стандарты лимфаденэктомии и обобщены данные о результатах применения современных методик оперативного лечения колоректального рака