5,024 research outputs found
Bayesian Information Criterion as an Alternative way of Statistical Inference
The article treats Bayesian information criterion as an alternative to traditional methods of statistical inference, based on NHST. The comparison of ANOVA and BIC results for psychological experiment is discussed
The results of diagnosis and treatment of chronic generalized catarrhal gingivitis in children at the background of chronic tonsillar infection
Biocenosis of sulcus in chronic generalized catarrhal gingivitis children (CGCG) without background pathology and with chronic tonsillitis (CH) has been investigated. Its development and clinical course depending on dominant microbial agent (streptococci or staphylococci) are specified. This expands our knowledge about etiology and pathogenesis of CGCG. The results of local immunity and nonspecific resistance study in CGCG children with/ without contaminant pathology are given. A new method of the patients under study treatment has been worked out and clinically tested. It has been established that the use of the complex offered allowes to reduce a number of complications, relapses, and increases the general efficacy of treatment.
Numerical analysis of the state of stress and strain in the Yenisei Ridge based on the regional tectonic state in the Asian continent
The paper presents the calculation of modern tectonic flow fields in the Yenisei Ridge located on the stable Siberian Craton. At the first stage, we solve the problem of calculating the average field of tectonic flows due to collisional processes at the southern and northeastern margins of the Eurasian Plate with Indian and Arabian and with North American plates, respectively. These calculations clarify the state of stress and the structure of tectonic flows on the territory of the Siberian Craton. The subtraction of the average displacements of the Siberian Craton as a whole in the northeast direction reveals the detailed structure of tectonic flows. Structural models are built along the Batolit-1982 and Shpat geological profiles crossing the Yenisei Ridge. At the second stage, we numerically study the state of stress and strain along these profiles determined by the global tectonics of Central and Southeast Asia, as well as their structural organization and interaction with the neighboring crustal elements
Fast-dissolving core-shell composite microparticles of quercetin fabricated using a coaxial electrospray process
This study reports on novel fast-dissolving core-shell composite microparticles of quercetin fabricated using coaxial electrospraying. A PVC-coated concentric spinneret was developed to conduct the electrospray process. A series of analyses were undertaken to characterize the resultant particles in terms of their morphology, the physical form of their components, and their functional performance. Scanning and transmission electron microscopies revealed that the microparticles had spherical morphologies with clear core-shell structure visible. Differential scanning calorimetry and X-ray diffraction verified that the quercetin active ingredient in the core and sucralose and sodium dodecyl sulfate (SDS) excipients in the shell existed in the amorphous state. This is believed to be a result of second-order interactions between the components; these could be observed by Fourier transform infrared spectroscopy. In vitro dissolution and permeation studies showed that the microparticles rapidly released the incorporated quercetin within one minute, and had permeation rates across the sublingual mucosa around 10 times faster than raw quercetin
Transport of magnetoexcitons in single and coupled quantum wells
The transport relaxation time and the mean free path of
magnetoexcitons in single and coupled quantum wells are calculated ( is the
magnetic momentum of the magnetoexciton). We present the results for
magnetoexciton scattering in a random field due to (i) quantum well width
fluctuations, (ii) composite fluctuations and (iii) ionized impurities. The
time depends nonmonotonously on in the case (ii) and in the cases
(i), (iii) for smaller than some critical value ( is the interwell
separation, is the magnetic length). For the
transport relaxation time increases monotonously with . The magnetoexciton
mean free path has a maximum at in the cases (i), (iii).
It decreases with increasing . The mean free path calculated for the case
(ii) may have two maxima. One of them disappears with the variation of the
random fields parameters. The maximum of increases with for
types (i,iii) of scattering processes and decreases in the case (ii).Comment: 13 pages, 8 figures in EPS format; Physica Scripta (in print
Experimental studies of thorium ions implantation from pulse laser plasma into thin silicon oxide layers
We report the results of experimental studies related to implantation of
thorium ions into thin silicon dioxide by pulsed plasma fluxes expansion.
Thorium ions were generated by laser ablation from a metal target, and the
ionic component of the laser plasma was accelerated in an electric field
created by the potential difference (5, 10 and 15 kV) between the ablated
target and SiO2/Si(001) sample. Laser ablation system installed inside the
vacuum chamber of the electron spectrometer was equipped with YAG:Nd3+ laser
having the pulse energy of 100 mJ and time duration of 15 ns in the Q-switched
regime. Depth profile of thorium atoms implanted into the 10 nm thick
subsurface areas together with their chemical state as well as the band gap of
the modified silicon oxide at different conditions of implantation processes
were studied by means of X-ray photoelectron spectroscopy (XPS) and Reflected
Electron Energy Loss Spectroscopy (REELS) methods. Analysis of chemical
composition showed that the modified silicon oxide film contains complex
thorium silicates. Depending on local concentration of thorium atoms, the
experimentally established band gaps were located in the range of 6.0 - 9.0 eV.
Theoretical studies of optical properties of the SiO2 and ThO2 crystalline
systems have been performed by ab initio calculations within hybrid functional.
Optical properties of the SiO2/ThO2 composite were interpreted on the basis of
Bruggeman effective medium approximation. A quantitative assessment of the
yield of isomeric nuclei in "hot" laser plasma at the early stages of expansion
has been performed. The estimates made with experimental results demonstrated
that the laser implantation of thorium ions into the SiO2 matrix can be useful
for further research of low-lying isomeric transitions in 229Th isotope with
energy of 7.8(0.5) eV
Study on antioxidant activity of Echinacea purpurea L. extracts and its impact on cell viability
This study investigates the antioxidant activity of Echinacea Purpurea L. (EP) extracts and its impact on cell viability. The polysaccharides content of EP was 159.8 ± 12.4 mg/g dry weight (DW), with extracts obtained by applying 55% ethanol at 55°C containing 11.0 ±1.0 mg gallic acid equivalent/g DW of total phenolic compound. Trolox equivalent antioxidant capacity, 0.1 mg/mL of EP extracts exhibited only 30% when compared to the ascorbic acid at the same concentration. Reducing power of extractsincreased linearly with its concentration and the concentration at 2.0 mg/mL reached about 65% of ascorbic acid at 0.3 mg/mL. The chelating capacity of ferrous iron (Fe2+) was 70% as good as that of thesynthetic metal chelater EDTA when added to 5.0 mg/mL of EP extracts. The DPPH scavenging capacity showed 85.1% at 0.5 mg/mL of extracts and with half-effective doses (ED50) was measured at 0.23mg/mL. The superoxide anions scavenging capacity of EP extracts was nearly equivalent to ascorbic acid (91.1% vs 93.0%) at the same concentration of 1.6 mg/mL and ED50 was 0.32 and 0.13 mg/mL, respectively. Microculture tetrazolium assays showed extracts had 92% cell viability at 1.6 mg/mL forchicken’s peripheral blood mononuclear cells (PBMCs) and 84% for RAW 264.7 macrophages, neither reaching the IC50 level. In summary, the EP extracts had antioxidant activity similar to that of ascorbic acid, but have no serious effect on inhibiting chicken’s PBMCs viability
Superfluidity of "dirty" indirect excitons and magnetoexcitons in two-dimensional trap
The superfluid phase transition of bosons in a two-dimensional (2D) system
with disorder and an external parabolic potential is studied. The theory is
applied to experiments on indirect excitons in coupled quantum wells. The
random field is allowed to be large compared to the dipole-dipole repulsion
between excitons. The slope of the external parabolic trap is assumed to change
slowly enough to apply the local density approximation (LDA) for the superfluid
density, which allows us to calculate the Kosterlitz-Thouless temperature
at each local point of the trap. The superfluid phase occurs
around the center of the trap () with the normal phase outside
this area. As temperature increases, the superfluid area shrinks and disappears
at temperature . Disorder acts to deplete the condensate; the
minimal total number of excitons for which superfluidity exists increases with
disorder at fixed temperature. If the disorder is large enough, it can destroy
the superfluid entirely. The effect of magnetic field is also calculated for
the case of indirect excitons. In a strong magnetic field , the superfluid
component decreases, primarily due to the change of the exciton effective mass.Comment: 13 pages, 3 figure
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