160 research outputs found
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
Recommended from our members
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
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
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
Sensitivity of Different Animal Species to Monkeypox Virus
Studied is the sensitivity of different animal species (white mice, rabbits, mini-pigs, and marmots) to Monkeypox virus (MPXV). Determined is the fact that MPXV-sensitive are groundhogs (ID50 and LD50 5 lg of PFU in case of intranasal inoculation). The most pronounced clinical signs of the disease such as varioliform eruption all over body and mucous linings, purulent discharges out of nasal cavity, lymphadenitis, loss of coordination, tremor of extremities, fever, hyper-aggressiveness, disheveled hair have been registered in groundhogs. The highest viral loads in the majority of fallen marmots have been observed in nasal mucosa, trachea, lungs, and pock-marked skin (>6,0 lg PFU/g). The symptomatology of the disease in mice as compared to groundhogs is a bit milder: purulent conjunctivitis, blepharitis, and disheveled hair. As for mini-pigs and rabbits, no visual signs of the disease have been observed in them
Mice as Animal Model for Evaluation of Therapeutic Efficacy of Preparations against Monkeypox
of MPV after 7 days postinfection, applying peroral administration once within 24 hours (24 hours before infection and 7 days after infection of mouse with 60 µg/g of a preparation). Displayed is the feasibility of using 8–15-days-old ICR mice (body weight 9–11 g) as an animal model for evaluation of therapeutic efficacy of the preparations under development against Monkeypox and smallpox
- …