101 research outputs found

    Application of Automated Microorganism Identification Systems for Verification of Taxonomic Appurtenance of the Collection Strains of Pathogenic Bacteria

    Get PDF
    Objective of the study is to optimize the algorithm for authenticity specification of pathogenic bacteria strains and to evaluate its efficacy for nomenclature examination of the isolates, Bacillus genus, from the State Collection of Pathogenic Bacteria functioning at the premises of RusRAPI “Microbe”, the authenticity of which bore scrutiny. Materials and methods. Methodological approach is based on application of automated microorganism identification systems: bacteriological analyzer Vitek 2, automatic ribotyping station DuPont Qualicon RiboPrinter System, and mass-spectrometer MicroFlex MALDI Biotyper, followed by complex assessment of the results obtained, using BioNumerics 7.1 software product. Results and conclusions. It is established that automated analyzers perform reasonably accurate identification of the investigated microorganisms in reference to their specie appurtenance. Vitek 2 shows the best efficiency. Unlike other analyzers, it allows for differentiation of B. anthracis STI-1 strain from a group of bacilli, B. cereus specie. It is of note that different systems range B. megaterium 5 strain in different ways. Carried out complex analysis of the results, obtained from all the three automated devices, using BioNumerics 7.1 software, relegates B. megaterium 5 to B. licheniformis with a high degree probability. Thus, it is necessary to include in the algorithm several techniques with subsequent complex analysis of the data obtained to specify authenticity and taxonomic appurtenance of the collection strains under nomenclature examination

    Structure and properties of aqueous dispersions of sodium dodecyl sulfate with carbon nanotubes

    Get PDF
    © 2016, Springer Science+Business Media New York.The dispersing action of the surfactant (sodium dodecyl sulfate, SDS) on the carbon nanotubes (CNT) in aqueous medium has been studied. Electron microscopy, molecular docking, NMR and IR spectroscopies were applied to determine the physical-chemical properties of CNT dispersions in SDS—water solutions. It was established that micellar adsorption of the surfactant on the surface of carbon material and solubilization of SDS in aqueous medium contribute to improving CNT dispersing in water solutions. It was shown that the non-polar hydrocarbon radicals of a single surfactant molecule form the highest possible number of contacts with the graphene surface. Upon increase of the SDS in solution these radicals form micelles connected with the surface of the nanotubes. At the sufficiently high SDS concentration the nanotube surface becomes covered with an adsorbed layer of surfactant micelles. Water molecules and sodium cations are concentrated in spaces between micelles. The observed pattern of micellar adsorption is somewhat similar to a loose bilayer of surfactant molecules

    Intraspecific Differentiation of <i>Francisella tularensis</i> Strains Using Multilocus Real-Time Polymerase Chain Reaction

    Get PDF
    The aim of the study was to develop a method for intraspecific differentiation of the tularemia microbe: subspecies tularensis (subpopulations AI and AII), holarctica (biovars japonica, EryS/R), mediasiatica, and novicida using multilocus real-time PCR. Materials and methods. We used 48 strains of F. tularensis of various subspecies, biovars, and subpopulations. Intraspecific appurtenance of the strains was carried out on the basis of the analysis of the RD-1 region variability applying PCR, the sdhA gene by Sanger fragment sequencing and by the disk diffusion method using disks with erythromycin. The selection of primers and probes was performed using the software available at www.genscript.com and GeneRunner 6.5.52. Sequence homology was assessed using the BLAST algorithm and the GenBank NCBI database. Results and discussion. New data on the structure and occurrence of the differentiation regions RD-8, RD-12, RD-28 of FTT1122c gene and its homologous sequences in strains of tularemia microbe of various subspecies have been obtained. Novel RDhm 346 bp in size, characteristic of strains of the subsp. mediasiatica, holarctica, which is deleted in subsp. tularensis and absent in subsp. novicida has been detected. Based on the detection of the FTT1670, FTT1122с, FTT1067, FTW_2084 loci, a multilocus real-time PCR has been developed – “F. tularensis 4c”, providing for identification of all subspecies of the tularemia microbe, separately for the biovar japonica of the Holarctic subspecies and subpopulations AI, AII of the subspecies tularensis. The PCR specificity was confirmed in the study of strains of tularemia microbe from the fund of the “State Collection of Pathogenic Bacteria” at the premises of the Russian Reserarch Anti-Plague Institute “Microbe”. The results obtained expand the concept of intraspecific genetic heterogeneity of tularemia microbe and possibilities of identifying the causative agent of tularemia using molecular-genetic methods. They are important for understanding the processes of adaptation of the pathogen to circulation in the host organism and environmental objects, the course of evolution and formation of new species of Francisella

    Oscillations and waves in solar spicules

    Get PDF
    Since their discovery, spicules have attracted increased attention as energy/mass bridges between the dense and dynamic photosphere and the tenuous hot solar corona. Mechanical energy of photospheric random and coherent motions can be guided by magnetic field lines, spanning from the interior to the upper parts of the solar atmosphere, in the form of waves and oscillations. Since spicules are one of the most pronounced features of the chromosphere, the energy transport they participate in can be traced by the observations of their oscillatory motions. Oscillations in spicules have been observed for a long time. However the recent high-resolutions and high-cadence space and ground based facilities with superb spatial, temporal and spectral capacities brought new aspects in the research of spicule dynamics. Here we review the progress made in imaging and spectroscopic observations of waves and oscillations in spicules. The observations are accompanied by a discussion on theoretical modelling and interpretations of these oscillations. Finally, we embark on the recent developments made on the presence and role of Alfven and kink waves in spicules. We also address the extensive debate made on the Alfven versus kink waves in the context of the explanation of the observed transverse oscillations of spicule axes

    Measurement invariance of Personal Well-Being Index (PWI-8) across 26 countries

    Get PDF
    This report examines the measurement invariance of the Personal Well-being Index with 8 items (PWI-8). University students (N = 5731) from 26 countries completed the measure either through paper and pencil or electronic mode. We examined uni-dimensional structure of PWI and performed a Multi-group CFA to assess the measurement invariance across the 26 countries, using conventional approach and the alignment procedure. The findings provide evidence of configural and partial metric invariance, as well as partial scalar invariance across samples. The findings suggest that PWI-8 can be used to examine correlates of life satisfaction across all included countries, however it is impossible to compare raw scores across countries

    The mental health continuum-short form: the structure and application for cross-cultural studies-A 38 nation study

    Get PDF
    Objective: The Mental Health Continuum-Short Form (MHC-SF) is a brief scale measuring positive human functioning. The study aimed to examine the factor structure and to explore the cross-cultural utility of the MHC-SF using bifactor models and exploratory structural equation modelling. Method: Using multigroup confirmatory analysis (MGCFA) we examined the measurement invariance of the MHC-SF in 38 countries (university students, N = 8,066; 61.73% women, mean age 21.55 years). Results: MGCFA supported the cross-cultural replicability of a bifactor structure and a metric level of invariance between student samples. The average proportion of variance explained by the general factor was high (ECV =.66), suggesting that the three aspects of mental health (emotional, social, and psychological well-being) can be treated as a single dimension of well-being. Conclusion: The metric level of invariance offers the possibility of comparing correlates and predictors of positive mental functioning across countries; however, the comparison of the levels of mental health across countries is not possible due to lack of scalar invariance. Our study has preliminary character and could serve as an initial assessment of the structure of the MHC-SF across different cultural settings. Further studies on general populations are required for extending our findings.info:eu-repo/semantics/acceptedVersio

    Belief in a zero-sum game and subjective well-being across 35 countries

    Get PDF
    This article presents a short research report on the relationship between perceived antagonism in social relations measured using the Belief in a Zero-Sum Game (BZSG) scale, life satisfaction, and positive and negative affect. Given that individuals who believe that life is like a zero-sum game are likely to perceive their daily interactions with others as unfair, we expected that individuals with high BZSG experience more negative affect and fewer positive one, resulting in a lower satisfaction with life. In addition, we examined whether country-level BZSG may play a moderating role in these associations. Data were collected from student samples (N = 7146) in 35 countries. Multilevel modelling revealed that perceived social antagonism in social relations is negatively associated with satisfaction with life and that this relationship is mediated by both positive and negative affect at the individual level. The relation of individual BZSG and negative affect on satisfaction with life were weaker in societies with higher country-level BZSG, suggesting that the effects of BZSG may be less detrimental in these countries. These findings extend previous knowledge about predictors of life satisfaction and suggest that social beliefs might also be an important factor that influences subjective well-being. The contribution of the study is that the separate treatment of life satisfaction and positive and negative affect may be helpful in many research situations, particularly from a cross-cultural perspective.info:eu-repo/semantics/publishedVersio

    Effective-Range Expansion of the Neutron-Deuteron Scattering Studied by a Quark-Model Nonlocal Gaussian Potential

    Full text link
    The S-wave effective range parameters of the neutron-deuteron (nd) scattering are derived in the Faddeev formalism, using a nonlocal Gaussian potential based on the quark-model baryon-baryon interaction fss2. The spin-doublet low-energy eigenphase shift is sufficiently attractive to reproduce predictions by the AV18 plus Urbana three-nucleon force, yielding the observed value of the doublet scattering length and the correct differential cross sections below the deuteron breakup threshold. This conclusion is consistent with the previous result for the triton binding energy, which is nearly reproduced by fss2 without reinforcing it with the three-nucleon force.Comment: 21 pages, 6 figures and 6 tables, submitted to Prog. Theor. Phy

    Belief in a zero-sum game and subjective well-being across 35 countries

    Get PDF
    This article presents a short research report on the relationship between perceived antagonism in social relations measured using the Belief in a Zero-Sum Game (BZSG) scale, life satisfaction, and positive and negative affect. Given that individuals who believe that life is like a zero-sum game are likely to perceive their daily interactions with others as unfair, we expected that individuals with high BZSG experience more negative affect and fewer positive one, resulting in a lower satisfaction with life. In addition, we examined whether country-level BZSG may play a moderating role in these associations. Data were collected from student samples (N=7146) in 35 countries. Multilevel modelling revealed that perceived social antagonism in social relations is negatively associated with satisfaction with life and that this relationship is mediated by both positive and negative affect at the individual level. The relation of individual BZSG and negative affect on satisfaction with life were weaker in societies with higher country-level BZSG, suggesting that the effects of BZSG may be less detrimental in these countries. These findings extend previous knowledge about predictors of life satisfaction and suggest that social beliefs might also be an important factor that influences subjective well-being. The contribution of the study is that the separate treatment of life satisfaction and positive and negative affect may be helpful in many research situations, particularly from a cross-cultural perspective
    corecore