4,240 research outputs found
EVIDENCE FOR FREE-RADICAL MEDIATED LIPID PEROXIDATION IN RATS AFTER COLD-IMMERSION STRESS
The role of cold immersion stress for the free-radical mediated lipid peroxidation in rat plasma and erythrocytes was studied. A model of cold-induced stress in rats was created. A significant increase of the level of thiobarbituric acid-reactive substances (TBARS) in plasma was found after chilling. Activated catabolic processes and xanthine-oxidase reactions during hypoxia could cause the increase measured in plasma levels of uric acid one hour after cold stress. A decrease in the antioxidant defence measured by uric acid consumption in rat blood plasma took also place already at the 3rd hour after chilling. These effects were not accompanied neither by elevated levels of TBARS, nor by a decrease in the reduced glutathione or elevated ratio of oxidized/ total glutathione in erythrocytes. The results indicated that lipid peroxidation was a component of the cold-induced stress in rats
Formation of Clusters in Mono Towns Located in Areas of Priority Socioeconomic Development
In the article the author considers cultural memory as a basis of the social wellbeing. Two concepts "cultural memory" and "social wellbeing", features of their interrelation, and also influence of the person on the cultural memory formation are investigated. Modern conditions offer modern solutions. We should remember on the one hand to be proud and to have wish for further development, on the other hand to draw some conclusions also for further development. In this case we could actively use the Internet possibilities and other modern technologies. By means of modern technology we have a big range of opportunities to help people not only in the financial sphere but also in the cultural one. It can give the chance to people not to feel alone in this world. So it means they can feel comfortable within their country, within the instability world. It is the aim of the most wellbeing programs
Antidiabetic Potential of Plants Used in Bulgarian Folk Medicine and Traditional Diet
The idea of this chapter is that currently available antidiabetic drugs specifically target several points of the T2D pathophysiology but they do not cover all aspects of the disease. In addition, many adverse effects of synthetic antidiabetic agents have been reported. The suggested manuscript is an overview of the available scientific literature focused on antiobesity and antidiabetic potential of selected 42 medicinal and edible plants of the Bulgarian flora. Most of the reports reveal the effect of extracts or their active components on specific biochemical mechanisms. Mechanistic data about hypoglycemic and hypolipidemic action are presented for some of the plants. An essential part of this review is dedicated to the target mechanisms behind the effects of the selected plant species. The authors hope that this review will serve as a starting point for future investigations with a contribution to the prevention and therapy of diabetes
Influence of creativity on thinking of the personality
This article touches upon a hot topic of the present, namely influence of creativity on thinking of the person. A problem point is the increase in negative impact of IP technologies at creativity development, so and persons that influences development of thinking and intelligence. Ways of overcoming of negative consequences of ignoring of creativity in favor of IP technologies are presented in articleДанная статья затрагивает актуальную тему современности, а именно влияние творчества на мышление человека. Проблемной точкой является увеличение негативного воздействия IP-технологий на развитие творчества, а значит и личности, что влияет на развитие мышления и интеллекта. В статье представлены пути преодоления отрицательных последствий игнорирования творчества в пользу IP-технологи
Metallicity Effect on LMXB Formation in Globular Clusters
We present comprehensive observational results of the metallicity effect on
the fraction of globular clusters (GC) that contain low-mass X-ray binaries
(LMXB), by utilizing all available data obtained with Chandra for LMXBs and HST
ACS for GCs. Our primary sample consists of old elliptical galaxies selected
from the ACS Virgo and Fornax surveys. To improve statistics at both the lowest
and highest X-ray luminosity, we also use previously reported results from
other galaxies. It is well known that the LMXB fraction is considerably higher
in red, metal-rich, than in blue, metal-poor GCs. In this paper, we test
whether this metallicity effect is X-ray luminosity-dependent, and find that
the effect holds uniformly in a wide luminosity range. This result is
statistically significant (at >= 3 sigma) in LMXBs with luminosities in the
range LX = 2 x 10^37 - 5 x 10^38 erg s-1, where the ratio of LMXB fractions in
metal-rich to metal-poor GCs is R = 3.4 +- 0.5. A similar ratio is also found
at lower (down to 10^36 erg s-1) and higher luminosities (up to the ULX
regime), but with less significance (~2 sigma confidence). Because different
types of LMXBs dominate in different luminosities, our finding requires a new
explanation for the metallicity effect in dynamically formed LMXBs. We confirm
that the metallicity effect is not affected by other factors such as stellar
age, GC mass, stellar encounter rate, and galacto-centric distance.Comment: 21 pages, 5 figures, accepted in Ap
Yang-Mills instantons and dyons on homogeneous G_2-manifolds
We consider Lie G-valued Yang-Mills fields on the space R x G/H, where G/H is
a compact nearly K"ahler six-dimensional homogeneous space, and the manifold R
x G/H carries a G_2-structure. After imposing a general G-invariance condition,
Yang-Mills theory with torsion on R x G/H is reduced to Newtonian mechanics of
a particle moving in R^6, R^4 or R^2 under the influence of an inverted
double-well-type potential for the cases G/H = SU(3)/U(1)xU(1),
Sp(2)/Sp(1)xU(1) or G_2/SU(3), respectively. We analyze all critical points and
present analytical and numerical kink- and bounce-type solutions, which yield
G-invariant instanton configurations on those cosets. Periodic solutions on S^1
x G/H and dyons on iR x G/H are also given.Comment: 1+26 pages, 14 figures, 6 miniplot
Supernova Ia: a Converging Delayed Detonation Wave
A model of a carbon-oxygen (C--O) presupernova core with an initial mass 1.33
M_\odot, an initial carbon mass fraction 0.27, and with an average mass
growth-rate 5 x 10^{-7} M_\odot/yr due to accretion in a binary system was
evolved from initial central density 10^9 g/cm^3, and temperature 2.05 x 10^8 K
through convective core formation and its subsequent expansion to the carbon
runaway at the center. The only thermonuclear reaction contained in the
equations of evolution and runaway was the carbon burning reaction 12C + 12C
with an energy release corresponding to the full transition of carbon and
oxygen (with the same rate as carbon) into 56Ni. As a parameter we take
\alpha_c - a ratio of a mixing length to the size of the convective zone. In
spite of the crude assumptions, we obtained a pattern of the runaway acceptable
for the supernova theory with the strong dependence of its duration on
\alpha_c. In the variants with large enough values of \alpha_c=4.0 x 10^{-3}
and 3.0 x 10^{-3} the fuel combustion occurred from the very beginning as a
prompt detonation. In the range of 2.0 x 10^{-3} >= \alpha_c >= 3.0 x 10^{-4}
the burning started as a deflagration with excitation of stellar pulsations
with growing amplitude. Eventually, the detonation set in, which was activated
near the surface layers of the presupernova (with m about 1.33 M_\odot) and
penetrated into the star down to the deflagration front. Excitation of model
pulsations and formation of a detonation front are described in detail for the
variant with \alpha_c=1.0 x 10^{-3}.Comment: 13 pages, 11 figures, to appear in Astronomy Letter
Canonical-type connection on almost contact manifolds with B-metric
The canonical-type connection on the almost contact manifolds with B-metric
is constructed. It is proved that its torsion is invariant with respect to a
subgroup of the general conformal transformations of the almost contact
B-metric structure. The basic classes of the considered manifolds are
characterized in terms of the torsion of the canonical-type connection.Comment: 11 pages, The final publication is available at
http://www.springerlink.co
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