Possibility of local pair existence in optimally doped SmFeAsO(1-x) in pseudogap regime

We report the analysis of pseudogap Delta* derived from resistivity experiments in FeAs-based superconductor SmFeAsO(0.85), having a critical temperature T_c = 55 K. Rather specific dependence Delta*(T) with two representative temperatures followed by a minimum at about 120 K was observed. Below T_s = 147 K, corresponding to the structural transition in SmFeAsO, Delta*(T) decreases linearly down to the temperature T_AFM = 133 K. This last peculiarity can likely be attributed to the antiferromagnetic (AFM) ordering of Fe spins. It is believed that the found behavior can be explained in terms of Machida, Nokura, and Matsubara (MNM) theory developed for the AFM superconductors.Comment: 5 pages, 2 figure

On the Conference «Regulatory Impact Assessment: How to Change Law, Experience and Practices»

On December 11, 2019, the VIth Russian Scientific and Practical Conference “Regulatory Impact Assessment: How to Change Law, Experience and Practices” was held in St. Petersburg. The conference, organized by the North-West Institute of Management of RANEPA and the Committee for Economic Development and Investment Activity of the Leningrad Region Administration, was devoted to the Institute of Regulatory Impact Assessment, an important and potentially effective procedure for improving the quality of public polic

Lamellar multilayer gratings with very high diffraction efficiency

The authors report here the development of a hard x-ray multilayer grating that has achieved an absolute efficiency of 34% at a wavelength of 1.54{angstrom}. The W-C multilayer itself has a reflectivity of 57% and the grating has a 0th order absolute efficiency of 36%. The origin of this extraordinarily high efficiency is that the short period and highly asymmetric structure of the gratings combined with its deep grooves allows light to interact with a large number of layer pairs. This increases angular separation of the diffraction orders and reduces the multilayer bandwidth to the point where there is little or no order to order overlap in the grating structure, and hence maximum intensity can be diffracted into a selected order. This paper reports on the development of an optimized multilayer grating and some of its unique characteristics

Implicit Sequence Learning under Interference Conditions

The influence of the Stroop interference effect on sequence learning was investigated. We examined suggestion that Stroop interference does not affect implicit sequence learning, but reduces the effectiveness of acquiring explicit sequence knowledge. The subjects were trained by using the serial reaction time task. The influencing factors were the sequence of stimuli (structured and pseudorandom) and the congruence of color name and font color (congruent and incongruent stimuli). The results revealed the effects of learning of the structured sequence in congruent and incongruent conditions. However, the low level of explicit knowledge found among subjects who performed the task in both conditions does not allow us to determine the effect of interference on the acquisition of explicit sequence knowl edge. It was also found that implicit sequence learning eliminated the effect of interference: the reaction time of subjects in congruent and incongruent conditions did not differ after training.Исследовалось влияние интерференционного эффекта Струпа на выучивание последовательностей. Проверялось предположение о том, что Струп-интерференция не влияет на имплицитное усвоение последовательности, но снижает продуктивность приобретения эксплицитного знания последовательности. Для обучения испытуемых использовалась задача быстрого реагирования на последовательность стимулов (the serial reaction time task). Воздействующими факторами выступали последовательность предъявления стимулов (структурированная и псевдослучайная) и согласованность названия цвета и цвета шрифта, которым оно написано (конгруэнтные и неконгруэнтные стимулы). Результаты выявили эффекты усвоения структурированной последовательности в конгруэнтных и неконгруэнтных условиях. При этом низкий уровень эксплицитного знания, установленный у испытуемых, выполнявших задание в обоих условиях, не позволяет определить влияние интерференции на получение эксплицитного знания последовательности. Кроме того, было обнаружено, что имплицитное усвоение последовательности приводит к устранению эффекта интерференции: после обучения время реакции испытуемых, находившихся в конгруэнтных и неконгруэнтных условиях, не отличалось

EFFECT OF THE PROPHAGE CTXΦ DELETION UPON PHENOTYPIC PROPERTIES IN STRAINS OF VIBRIO CHOLERAE BIOVAR EL TOR, ASSOCIATED WITH VIRULENCE AND PERSISTENCE

Objective of the study is to evaluate the influence of CTXφ prophage deletion, which carries ctxAB genes, on phenotypical properties associated with pathogenicity or biofilm formation in non-toxigenic mutants. Materials and methods. Utilized have been the clinical strains of Vibrio cholerae biovar El Tor and their spontaneous non-toxigenic mutants that lost CTXφ prophage. Applied have been microbiological and biochemical methods, inoculation of model animals with cells of the strains under study. Results and conclusions. The results of comparative analysis of phenotypic properties in isogenic toxigenic and non-toxigenic strains of Vibrio cholerae biovar El Tor, which lost CTXφ prophage encoding the cholera toxin, are represented. It is established that the deletion of CTXφ prophage leads to the simultaneous change of several phenotypic properties associated with virulence (colonizing ability, production of soluble hemagglutinin/protease and heat labile hemolysin/cytolysin) and biofilm formation (motility, exopolysaccharide biosynthesis) in spontaneous non-toxigenic mutants. It is suggested that the reason for these phenotypic changes in the mutants might be the changes in activity of the related to each other regulatory genes controlling virulence and biofilm formation process in cholera agent

Construction of PCR Test-System for Differentiation between Genetically Altered Toxigenic Vibrio cholerae Strains, Biovar El Tor, with Varied Epidemic Potential

Designed is a multi-locus PCR test-system that allows for differentiation between genetically altered Vibrio cholerae strains, biovar El Tor, with high and low epidemic potential respectively, based on identification of genetic marker structure in the agent of the seventh cholera pandemic - pandemicity island VSP-II. In the course of investigations selected have been three target genes allocated in the central region and terminal end of the mobile genetic element. This test-system offers the possibility to identify the strains containing intact VSP-II, the ones containing VSP-II with a short-length deletion, and the strains with VSP-II with extended deletion. The first two are classified as the variants with low epidemic potential, while the last ones - as the variants with high epidemic potential. Specificity and efficacy of the test-system is shown by the experiments with 28 toxigenic genetically altered V. cholerae strains, biovar El Tor, and 6 strains of closely related species and enterobacteria. The results obtained coincide with the data on mono-locus PCR assay and in a number of instances are verified by sequencing

Inhibitors of the sodium-glucose transporter type 2 and new possibilities for managing vascular age in patients with type 2 diabetes mellitus

The article discusses the pathophysiological mechanisms of the development of vascular aging as a combination of the influence on the  body of  genetic, environmental, regulatory, metabolic and other factors causing biochemical, enzymatic and cellular changes in the arterial vascular bed. The concept of “early vascular aging” and “healthy vascular aging” is defined depending on the ratio of the biological and chronological age of the vessels. The role of diabetes mellitus in increasing vascular stiffness, early vascular aging, as well as the  progression of  atherosclerotic cardiovascular diseases and their complications is considered in detail. Approaches to multifactorial management of vascular age in patients with type 2 diabetes (lifestyle modification with strategy of aggressive treatment of modifiers of atherosclerosis, rejection of bad habits, adherence to dietary recommendations and the use of modern organo- and vasoprotective antidiabetic drugs) are revealed. The mechanism of realization of vasoprotective effects of inhibitors of sodium-glucose transporter-2 (iNGLT-2) is described in detail. The results of completed large random ized trials EMPA-REG Outcome and EMPA-REG BP of the most studied representative of the IGLT-2 group, empagliflozin, are presented. It has been shown that due to their glucose and natriuretic effects, the ability to reduce body weight and blood pressure, improve myocardial metabolism and bioenergetics, decrease the activity of the sympathetic nervous system, as well as positive effects on vascular stiffness, NGLT-2 inhibitors are the drugs of choice in patients with type 2 diabetes mellitus (T2DM) and cardiovascular diseases. This makes it possible to widely use this group of drugs for managing the vascular age of patients and represents a new opportunity in the prevention of vascular aging in T2DM

Spectral properties of high-gain parametric down-conversion

High-gain parametric down-conversion (PDC) is a source of bright squeezed vacuum, which is a macroscopic nonclassical state of light and a promising candidate for quantum information applications. Here we study its properties, such as the intensity spectral width and the spectral width of pairwise correlations.Comment: 9 pages, 5 figure