304 research outputs found
Scattered Light Measurement for the Birefringence Distribution Estimations
The technique based on the digital processing of recorded scattered light distribution enabling for the measurement of the birefringence profile in non-uniform anisotropic materials was proposed.
Keywords: measurement technique, birefringence distribution, scattered light, tempered glas
VARIANCE OF BIOLOGICAL PROPERTIES OF OPPORTUNISTIC STAPHYLOCOCCUS UNDER NEGATIVE AERO IONS INFLUENCE
The aim. of this research was to study some changes of staphylococcus biological properties under negative aero ions influence and lactobacillus. We applied a disco-diffuse method for detection of bacterial sensitivity to antimicrobials and. evaluated of the minimal inhibitory concentration by bacteriologic analyzer. Then we studied impact of negative aeroions flow on both isolated staphylococcus culture and. mixed with lactobacilli. Aeroions flow inhibits staphylococcal growth, decrease its sensitivity to antibiotics in vitro both in isolated culture, and. mixed with lactobacilli. Combined application of probiotics and. negative aeroions could be a new approach for changes of antimicrobial sensitivity
Interaction of Nitrogen-Vacancy Centers in Diamond with a Dense Ensemble of Carbon-13
The nitrogen-vacancy center in diamond attracts a lot of attention in sensing
applications, mainly for temperature, magnetic field, and rotation
measurements. Nuclear spins of carbon-13 surrounding the nitrogen-vacancy
center can be used as a memory or sensing element. In the current work, a
diamond plate with a relatively large concentration of carbon-13 was
synthesized and examined. The spectrum of optically detected magnetic resonance
was recorded and analyzed in a magnetic field range of 5-200 G. A
strain-independent measurement technique of carbon-13 isotope concentration
based on the analysis of magnetic resonance spectra was developed.
Additionally, narrow features in the spectrum were detected and understood
How Chaotic is the Stadium Billiard? A Semiclassical Analysis
The impression gained from the literature published to date is that the
spectrum of the stadium billiard can be adequately described, semiclassically,
by the Gutzwiller periodic orbit trace formula together with a modified
treatment of the marginally stable family of bouncing ball orbits. I show that
this belief is erroneous. The Gutzwiller trace formula is not applicable for
the phase space dynamics near the bouncing ball orbits. Unstable periodic
orbits close to the marginally stable family in phase space cannot be treated
as isolated stationary phase points when approximating the trace of the Green
function. Semiclassical contributions to the trace show an - dependent
transition from hard chaos to integrable behavior for trajectories approaching
the bouncing ball orbits. A whole region in phase space surrounding the
marginal stable family acts, semiclassically, like a stable island with
boundaries being explicitly -dependent. The localized bouncing ball
states found in the billiard derive from this semiclassically stable island.
The bouncing ball orbits themselves, however, do not contribute to individual
eigenvalues in the spectrum. An EBK-like quantization of the regular bouncing
ball eigenstates in the stadium can be derived. The stadium billiard is thus an
ideal model for studying the influence of almost regular dynamics near
marginally stable boundaries on quantum mechanics.Comment: 27 pages, 6 figures, submitted to J. Phys.
Tuberculosis in HIV-infected children in Europe, Thailand and Brazil: paediatric TB-HIV EuroCoord study
SETTING: Centres participating in the Paediatric European Network for Treatment of AIDS (PENTA), including Thailand and Brazil.
OBJECTIVE: To describe the incidence, presentation, treatment and treatment outcomes of tuberculosis (TB) in human immunodeficiency virus (HIV) infected children.
DESIGN: Observational study of TB diagnosed in HIV-infected children in 2011–2013.
RESULTS: Of 4265 children aged <16 years, 127 (3%) were diagnosed with TB: 6 (5%) in Western Europe, 80 (63%) in Eastern Europe, 27 (21%) in Thailand and 14 (11%) in Brazil, with estimated TB incidence rates of respectively 239, 982, 1633 and 2551 per 100 000 person-years (py). The majority (94%) had acquired HIV perinatally. The median age at TB diagnosis was 6.8 years (interquartile range 3.0–11.5). Over half (52%) had advanced/severe World Health Organization stage immunodeficiency; 67 (53%) were not on antiretroviral therapy (ART) at TB diagnosis. Preventive anti-tuberculosis treatment was given to 23% (n = 23) of 102 children diagnosed with HIV before TB. Eleven children had unfavourable TB outcomes: 4 died, 5 did not complete treatment, 1 had recurrent TB and 1 had an unknown outcome. In univariable analysis, previous diagnosis of acquired immune-deficiency syndrome, not being virologically suppressed on ART at TB diagnosis and region (Brazil) were significantly associated with unfavourable TB outcomes.
CONCLUSION: Most TB cases were from countries with high TB prevalence. The majority (91%) had favourable outcomes. Universal ART and TB prophylaxis may reduce missed opportunities for TB prevention
The role of urokinase, T-cadherin and adiponetin in the development of endogenous depressive disorders
Purpose of the study To determine the role of genes that regulate the processes of nerve cell migration and directed growth of nerve fibers of navigation receptors (PLAUR and CDH13) or their ligands (PLAU, PLAT, ADIPOQ) in the development of endogenous depression and schizophrenia in the Russian population.Цель работы – определить роль генов, регулирующих процессы миграции нервных клеток и направленного роста нервных волокон навигационных рецепторов (PLAUR и CDH13) или их лигандов (PLAU, PLAT, ADIPOQ) в развитии эндогенной депрессии и шизофрении в российской популяции
The 2175 A dust feature in a Gamma Ray Burst afterglow at redshift 2.45
We present optical and near-infrared photometry of the afterglow of the long
Gamma-Ray Burst GRB 070802 at redshift 2.45 obtained with the ESO/MPI 2.2 m
telescope equipped with the multi-channel imager GROND. Follow-up observations
in g'r'i'z' and JHK_S bands started ~17 min and extended up to 28 h post burst.
We find an increase in brightness of the afterglow at early times, which can be
explained by the superposition of reverse and forward shock (FS) emission or
the onset of the afterglow FS. Additionally, we detect a strong broad-band
absorption feature in the i' band, which we interpret as extinction from the
redshifted 2175 A bump in the GRB host galaxy. This is one of the first and
clearest detections of the 2175 A feature at high redshift. It is strong
evidence for a carbon rich environment, indicating that Milky Way or Large
Magellanic Cloud like dust was already formed in substantial amounts in a
galaxy at z=2.45.Comment: 21 pages, 3 figures, accepted for publication by Ap
The complex light-curve of the afterglow of GRB071010A
We present and discuss the results of an extensive observational campaign
devoted to GRB071010A, a long-duration gamma-ray burst detected by the Swift
satellite. This event was followed for almost a month in the
optical/near-infrared (NIR) with various telescopes starting from about 2min
after the high-energy event. Swift-XRT observations started only later at about
0.4d. The light-curve evolution allows us to single out an initial rising phase
with a maximum at about 7min, possibly the afterglow onset in the context of
the standard fireball model, which is then followed by a smooth decay
interrupted by a sharp rebrightening at about 0.6d. The rebrightening was
visible in both the optical/NIR and X-rays and can be interpreted as an episode
of discrete energy injection, although various alternatives are possible. A
steepening of the afterglow light curve is recorded at about 1d. The entire
evolution of the optical/NIR afterglow is consistent with being achromatic.
This could be one of the few identified GRB afterglows with an achromatic break
in the X-ray through the optical/NIR bands. Polarimetry was also obtained at
about 1d, just after the rebrightening and almost coincident with the
steepening. This provided a fairly tight upper limit of 0.9% for the
polarized-flux fraction.Comment: 11 pages, 3 figures, MNRAS, in pres
The Foundation Supernova Survey: Motivation, design, implementation, and first data release
© 2017 The Author(s). The Foundation Supernova Survey aims to provide a large, high-fidelity, homogeneous, and precisely calibrated low-redshift Type Ia supernova (SN Ia) sample for cosmology. The calibration of the current low-redshift SN sample is the largest component of systematic uncertainties for SN cosmology, and new data are necessary to make progress. We present the motivation, survey design, observation strategy, implementation, and first results for the Foundation Supernova Survey. We are using the Pan-STARRS telescope to obtain photometry for up to 800 SNe Ia at z>~0.1. This strategy has several unique advantages: (1) the Pan-STARRS system is a superbly calibrated telescopic system, (2) Pan-STARRS has observed 3/4 of the sky in grizyP1 making future template observations unnecessary, (3) we have a well-tested data-reduction pipeline, and (4) we have observed ~3000 high-redshift SNe Ia on this system. Here, we present our initial sample of 225 SN Ia grizP1light curves, of which 180 pass all criteria for inclusion in a cosmological sample. The Foundation Supernova Survey already contains more cosmologically useful SNe Ia than all other published low-redshift SN Ia samples combined. We expect that the systematic uncertainties for the Foundation Supernova Sample will be two to three times smaller than other low-redshift samples.We find that our cosmologically useful sample has an intrinsic scatter of 0.111 mag, smaller than other low-redshift samples. We perform detailed simulations showing that simply replacing the current low-redshift SN Ia sample with an equally sized Foundation sample will improve the precision on the dark energy equation-of-state parameter by 35 per cent, and the dark energy figure of merit by 72 per cent
The complex light-curve of the afterglow of GRB071010A
We present and discuss the results of an extensive observational campaign
devoted to GRB071010A, a long-duration gamma-ray burst detected by the Swift
satellite. This event was followed for almost a month in the
optical/near-infrared (NIR) with various telescopes starting from about 2min
after the high-energy event. Swift-XRT observations started only later at about
0.4d. The light-curve evolution allows us to single out an initial rising phase
with a maximum at about 7min, possibly the afterglow onset in the context of
the standard fireball model, which is then followed by a smooth decay
interrupted by a sharp rebrightening at about 0.6d. The rebrightening was
visible in both the optical/NIR and X-rays and can be interpreted as an episode
of discrete energy injection, although various alternatives are possible. A
steepening of the afterglow light curve is recorded at about 1d. The entire
evolution of the optical/NIR afterglow is consistent with being achromatic.
This could be one of the few identified GRB afterglows with an achromatic break
in the X-ray through the optical/NIR bands. Polarimetry was also obtained at
about 1d, just after the rebrightening and almost coincident with the
steepening. This provided a fairly tight upper limit of 0.9% for the
polarized-flux fraction.Comment: 11 pages, 3 figures, MNRAS, in pres
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