Trends of the major porin gene (ompF) evolution

OmpF is one of the major general porins of Enterobacteriaceae that belongs to the first line of bacterial defense and interactions with the biotic as well as abiotic environments. Porins are surface exposed and their structures strongly reflect the history of multiple interactions with the environmental challenges. Unfortunately, little is known on diversity of porin genes of Enterobacteriaceae and the genus Yersinia especially. We analyzed the sequences of the ompF gene from 73 Yersinia strains covering 14 known species. The phylogenetic analysis placed most of the Yersinia strains in the same line assigned by 16S rDNA-gyrB tree. Very high congruence in the tree topologies was observed for Y. enterocolitica, Y. kristensenii, Y. ruckeri, indicating that intragenic recombination in these species had no effect on the ompF gene. A significant level of intra- and interspecies recombination was found for Y. aleksiciae, Y. intermedia and Y. mollaretii. Our analysis shows that the ompF gene of Yersinia has evolved with nonrandom mutational rate under purifying selection. However, several surface loops in the OmpF porin contain positively selected sites, which very likely reflect adaptive diversification Yersinia to their ecological niches. To our knowledge, this is a first investigation of diversity of the porin gene covering the whole genus of the family Enterobacteriaceae. This study demonstrates that recombination and positive selection both contribute to evolution of ompF, but the relative contribution of these evolutionary forces are different among Yersinia species

Orientation effects and figures of merit in advanced 2-2-type composites based on [011]-poled domain-engineered single crystals

The paper reports new results that compare the group of performance figures of merit of piezo-active 2-2-type composites based on [011]-poled domain-engineered (1 - x)Pb(Zn1/3Nb2/3)O3-xPbTiO3 single crystals, where the main crystallographic axes in the crystal layers are rotated to tailor effective electromechanical properties and related parameters. Examples of the orientation and volume-fraction dependences of the figures of merit are analysed for the first time for the system of 2-2 single crystal/polymer composites and 2-0-2 single crystal/corundum ceramic/polymer composites at x = 0.0475-0.09. The connections between the piezoelectric coefficients, energy-harvesting figures of merit and modified figures of merit (j = 1, 2 and 3) are highlighted during rotation of the main X and Y crystallographic axes around the Z axis of the crystal layers. A similar orientation behaviour of, and and their large anisotropy are studied at specific volume fractions of the single-crystal component and for a variety of microgeometric architectures of a corundum ceramic/polymer layer with 0-3 connectivity. Maxima of the longitudinal parameters, and at x = 0.0475-0.09 and constant volume fraction of the single-crystal component of the 2-2-type composites are observed in a relatively narrow orientation range. A new performance diagram is built to show regions of a large anisotropy of and in a 2-0-2 composite and, as a result of the large piezoelectric coefficients and figures of merit, the composites show significant potential in the field of piezoelectric energy-harvesting and sensor applications. This journal is </p

Relationships between piezoelectric and energy-harvesting characteristics of 1–2–2 composites based on domain-engineered single crystals

The paper reports on the piezoelectric performance, electromechanical coupling and related energy-harvesting figures of merit of three forms of 1–2–2 composites based on domain-engineered single crystals. The effect of the single-crystal piezoelectric properties and elastic properties of the laminar polymer matrix on the appropriate figures of merit of the composite is studied. The main active components of the studied composites are [0 0 1]-poled perovskite-type single crystals with chemical compositions: 0.92Pb(Zn1/3Nb2/3)O3–0.08PbTiO3, 0.67Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 and [Li x (K1−y Na y)1−x ](Nb1−z Ta z)O3: Mn, where x = 0.06, y = 0.1–0.3, z = 0.07–0.17, and the level of Mn doping is 0.25 mol. %. Examples of non-monotonic volume-fraction dependences of the piezoelectric properties, figures of merit and anisotropy factors are analysed. New diagrams are first built to demonstrate the volume-fraction regions where a large anisotropy of the piezoelectric coefficients d 3j * and electromechanical coupling factors k 3j * is achieved, and where energy-harvesting figures of merit of the composite are at least five times larger than analogous parameters of single-crystal components. The studied 1–2–2 composites are of interest as anisotropic materials with high piezoelectric sensitivity and large figures of merit which are important for sensor, energy-harvesting and related applications.</p

Piezoelectric sensitivity and hydrostatic response of novel lead-free 2–0–2 composites with two single-crystal components

This paper reports the piezoelectric performance and important related hydrostatic parameters of 2–0–2 composites based on lead-free ferroelectric and piezoelectric single crystals with 4mm symmetry. We demonstrate that ferroelectric domain-engineered alkali niobate-tantalate based single crystals provide large values of the piezoelectric coefficients g3j ∗ and related parameters when used in a 2–0–2 composite system with a relatively wide range of volume fractions of single-crystal components. An ‘aspect-ratio effect’ as a result of the presence of inclusions of a piezoelectric Li2B4O7 single crystal in a polymer medium is studied for the first time for a case where the elastic compliance s12 in the single crystal/polymer layer of the composite passes through zero. It is observed that changes in the aspect ratio and volume fraction of the Li2B4O7 inclusions influence the hydrostatic piezoelectric coefficient gh ∗, squared figure of merit dh ∗gh ∗ and electromechanical coupling factor kh ∗ of the composite, and large values of gh ∗∼102 mV·m/N, dh ∗gh ∗∼ (10−11–10−10) Pa−1 and kh ∗≈ 0.6–0.7 are achieved. A link between max kh ∗ and a change in sgns12 is first described for the 2–2-type composite, and a comparison of the hydrostatic parameters of the novel and related composites is made. The present results show the potential of lead-free 2–0–2 composites that are suitable for piezoelectric sensor, energy-harvesting and hydroacoustic applications.</p

Hourly average values of solar wing parameters (flow rate and ion temperatures) according to data of measurements of the Venera-9 and Venera-10 automatic interplanetary stations on an Earth-Venus during the period June 1975 - April 1976

Four electrostatic analyzers with channel electron multipliers as detectors were used to measure solar wind ionic flow. The axes of the fields of vision of two of these analyzers were directed along the axis of the automatic interplanetary station, oriented towards the Sun, while the other two were turned in one plane at angles of +15 deg and -15 deg. The full hemisphere of the angular diagram of each analyzer was approximately 5 deg. The energetic resolution was approximately 6%, and the geometric energy was 0.002 sq cm ave. keV. Each analyzer covered an energetic range of approximately 10 in eight energetic intervals. Spectral distributions were processed in order to obtain the velocity and temperature of the protons. Tabular data show the hour interval (universal time) and the average solar wind velocity in kilometers per second

Oxidation of 2-carene by means of potassium permanganate

The oxidation of 2-carene with KMnO4 leads to the formation of 2 α,3 α-caranediol and 3 α-hydroxy-2-caranone. The reduction of the latter with KBH4 gives 2 β, 3 α-caranediol. © 1975 Plenum Publishing Corporation

Frequency of Interferon-Resistance Conferring Substitutions in Amino Acid Positions 70 and 91 of Core Protein of the Russian HCV 1b Isolates Analyzed in the T-Cell Epitopic Context

Funding Information: This study was supported by the grant of the Russian Science Foundation (Project ID 15-15-30039). Mobility and training of the researchers was supported by the grants of the Swedish Institute (TP 09272/2013 and PI 19806/2016). Publisher Copyright: © 2018 V. S. Kichatova et al.Amino acid substitutions R70Q/H and L91M in HCV subtype 1b core protein can affect the response to interferon and are associated with the development of hepatocellular carcinoma. We found that the rate of R70Q/H in HCV 1b from Russia was 31.2%, similar to that in HCV strains from Asia (34.0%), higher than that in the European (18.0%, p=0.0010), but lower than that in the US HCV 1b strains (62.8%, p<0.0001). Substitution L91M was found in 80.4% of the Russian HCV 1b isolates, higher than in Asian isolates (43.8%, p<0.0001). Thus, a significant proportion of Russian HCV 1b isolates carry the unfavorable R70Q/H and/or L91M substitution. In silico analysis of the epitopic structure of the regions of substitutions revealed that both harbor clusters of T-cell epitopes. Peptides encompassing these regions were predicted to bind to a panel of HLA class I molecules, with substitutions impairing peptide recognition by HLA I molecules of the alleles prevalent in Russia. This indicates that HCV 1b with R70Q/H and L91M substitutions may have evolved as the immune escape variants. Impairment of T-cell recognition may play a part in the negative effect of these substitutions on the response to IFN treatment.Peer reviewe

FEATURES OF IMMUNOCOMPETENT CELLS IN THE PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA AT PRIMARY DIAGNOSIS

Some basic parameters of immune profile have been investigated in 140 patients with chronic lymphocytic leukemia (CLL). There was shown that the cohort of CLL patients is heterogeneous for their immune profile as early as at primary diagnosis stage, showing sufficient differences in the numbers of immunocompetent cells in peripheral blood. In most cases, the interpretation of appropriate quantitative characteristics is quite difficult, if based on the conventional criteria. The numbers of activated T-lymphocytes and NK-cells were proven to be the most informative parameters of cellular immunity in this cohort. Progression of leukemic events shows a close association with only a single parameter under study, i.e., CD4+/CD8+ cell ratio

THE RESULTS OF THE STUDY OF VARIETIES OF ALFALFA IN THE CENTRAL-CHERNOZEM ZONE

Three-year study of one hundred world collection of alfalfa was conducted in Central Black-Earth zone of Russia. The varieties of Medicago × varia ‘Zheltogibridnaya 99’, ‘Flora 2’, ‘Karlygash’ and ‘№ 152’ (hybrid ‘Severnaya hybridnaya’ בAugune II’) were recommended for breeding programs. The most variable were character of seed production, productivity of green mass and hay yield productivity; character of foliage and the intensity of regrowth of plants on the 20-th day after spring regrowth had medium variability. The height before the first mowing and height in the phase of full flowering had low variability. There was a significant correlation between the yield of green mass and hay, the yield of green mass and intensity of regrowth and a weak negative correlation between the yield of green mass and seed yield