2,831 research outputs found
Planck Observations of M33
We have performed a comprehensive investigation of the global integrated flux
density of M33 from radio to ultraviolet wavelengths, finding that the data
between 100 GHz and 3 THz are accurately described by a single modified
blackbody curve with a dust temperature of = 21.670.30 K
and an effective dust emissivity index of = 1.350.10,
with no indication of an excess of emission at millimeter/sub-millimeter
wavelengths. However, sub-dividing M33 into three radial annuli, we found that
the global emission curve is highly degenerate with the constituent curves
representing the sub-regions of M33. We also found gradients in
and across the disk of M33, with both
quantities decreasing with increasing radius. Comparing the M33 dust emissivity
with that of other Local Group members, we find that M33 resembles the
Magellanic Clouds rather than the larger galaxies, i.e., the Milky Way and M31.
In the Local Group sample, we find a clear correlation between global dust
emissivity and metallicity, with dust emissivity increasing with metallicity. A
major aspect of this analysis is the investigation into the impact of
fluctuations in the Cosmic Microwave Background (CMB) on the integrated flux
density spectrum of M33. We found that failing to account for these CMB
fluctuations would result in a significant over-estimate of
by 5 K and an under-estimate of by 0.4.Comment: Accepted for publication in MNRA
Development Of The Extraction Method Of Inactive Forms Of Pectin Substances From Fruits To Easy-digestible Active Form During The Obtaining Of Nanofood
The aim of the work is development of a unique method for deep processing of fruits and vegetables with a high content of sparingly soluble pectin substances, which makes it possible to remove pectic substances from inactive form and transform them into an easily digestible active form when obtaining natural semi-finished products and food products in nanosized form. To achieve the aim, a complex effect on the raw material of steam-thermal treatment or cryogenic shock freezing and fine-dispersed grinding is used as an innovation.A new method for obtaining finely dispersed additives and health products from fruits and vegetables with a high content of biologically active substances (BAS) and prebiotic substances is developed, which is based on a complex effect on raw materials of processes of steam-thermal or cryogenic treatment of raw materials and fine-dispersed grinding, which is accompanied by destruction, mechanochemistry, non-enzymatic catalysis. It is found that when these processes are activated, pectic substances are activated, more complete extraction from raw materials (4.5 ... 7.3 times) from a latent form and transformation into a soluble form. The mechanism of these processes is disclosed, recommendations for the creation of recreational nanoproducts are developed. It is shown that, in parallel, non-enzymatic catalysis (up to 70%) of hardly soluble pectic substances in individual monomers takes place, that is, transformation into a soluble, easily digestible form.The increase and seizures of latent forms of biologically active substances in finely dispersed frozen and heat-treated purees from fruit compared with fresh raw materials is established. The increase is respectively 1.5 ... 4.0 times and 1.5 ... 3.0 times. The quality of the obtained new types of fine mashed potatoes exceeds the known analogs for BAS content and technological characteristics. New types of purees are in a nanoscale, easily digestible form.With the use of new types of finely dispersed additives, a wide range of products for health-improving nutrition has been developed with a record content of natural BASs (new types of nano-lipids, nanosorb products, milk-vegetable cocktails, fillings for confectionery and extruded products, curd desserts, bakery products, snacks - falafel, creams, etc.)
On the relationship between cyclic and hierarchical three-species predator-prey systems and the two-species Lotka-Volterra model
We aim to clarify the relationship between interacting three-species models
and the two-species Lotka-Volterra (LV) model. We utilize mean-field theory and
Monte Carlo simulations on two-dimensional square lattices to explore the
temporal evolution characteristics of two different interacting three-species
predator-prey systems: (1) a cyclic rock-paper-scissors (RPS) model with
conserved total particle number but strongly asymmetric reaction rates that
lets the system evolve towards one corner of configuration space; (2) a
hierarchical food chain where an additional intermediate species is inserted
between the predator and prey in the LV model. For model variant (1), we
demonstrate that the evolutionary properties of both minority species in the
steady state of this stochastic spatial three-species corner RPS model are well
approximated by the LV system, with its emerging characteristic features of
localized population clustering, persistent oscillatory dynamics, correlated
spatio-temporal patterns, and fitness enhancement through quenched spatial
disorder in the predation rates. In contrast, we could not identify any regime
where the hierarchical model (2) would reduce to the two-species LV system. In
the presence of pair exchange processes, the system remains essentially
well-mixed, and we generally find the Monte Carlo simulation results for the
spatially extended model (2) to be consistent with the predictions from the
corresponding mean-field rate equations. If spreading occurs only through
nearest-neighbor hopping, small population clusters emerge; yet the requirement
of an intermediate species cluster obviously disrupts spatio-temporal
correlations between predator and prey, and correspondingly eliminates many of
the intriguing fluctuation phenomena that characterize the stochastic spatial
LV system.Comment: 13 pages, 4 figures; to appear in Eur. Phys. J. B (2012
Correlations, fluctuations and stability of a finite-size network of coupled oscillators
The incoherent state of the Kuramoto model of coupled oscillators exhibits
marginal modes in mean field theory. We demonstrate that corrections due to
finite size effects render these modes stable in the subcritical case, i.e.
when the population is not synchronous. This demonstration is facilitated by
the construction of a non-equilibrium statistical field theoretic formulation
of a generic model of coupled oscillators. This theory is consistent with
previous results. In the all-to-all case, the fluctuations in this theory are
due completely to finite size corrections, which can be calculated in an
expansion in 1/N, where N is the number of oscillators. The N -> infinity limit
of this theory is what is traditionally called mean field theory for the
Kuramoto model.Comment: 25 pages (2 column), 12 figures, modifications for resubmissio
B polarization of the CMB from Faraday rotation
We study the effect of Faraday rotation due to a homogeneous magnetic field
on the polarization of the cosmic microwave background (CMB). Scalar
fluctuations give rise only to parity-even E-type polarization of the CMB.
However in the presence of a magnetic field, a non-vanishing parity-odd B-type
polarization component is produced through Faraday rotation. We derive the
exact solution for the E and B modes generated by scalar perturbations
including the Faraday rotation effect of a uniform magnetic field, and evaluate
their cross-correlations with temperature anisotropies. We compute the angular
autocorrelation function of the B-modes in the limit that the Faraday rotation
is small. We find that primordial magnetic fields of present strength around
G rotate E-modes into B-modes with amplitude comparable to those
due to the weak gravitational lensing effect at frequencies around
GHz. The strength of B-modes produced by Faraday rotation scales as
. We evaluate also the depolarizing effect of Faraday rotation upon
the cross correlation between temperature anisotropy and E-type polarization.Comment: 11 pages, 4 figures. Minor changes to match the published versio
Reaction-diffusion processes in zero transverse dimensions as toy models for high-energy QCD
We examine numerically different zero-dimensional reaction-diffusion
processes as candidate toy models for high-energy QCD evolution. Of the models
examined -- Reggeon Field Theory, Directed Percolation and Reversible Processes
-- only the latter shows the behaviour commonly expected, namely an increase of
the scattering amplitude with increasing rapidity. Further, we find that
increasing recombination terms, quantum loops and the heuristic inclusion of a
running of the couplings, generically slow down the evolution.Comment: 17 pages, 7 figure
The relativistic statistical theory and Kaniadakis entropy: an approach through a molecular chaos hypothesis
We have investigated the proof of the theorem within a manifestly
covariant approach by considering the relativistic statistical theory developed
in [G. Kaniadakis, Phy. Rev. E {\bf 66}, 056125, 2002; {\it ibid.} {\bf 72},
036108, 2005]. As it happens in the nonrelativistic limit, the molecular chaos
hypothesis is slightly extended within the Kaniadakis formalism. It is shown
that the collisional equilibrium states (null entropy source term) are
described by a power law generalization of the exponential Juttner
distribution, e.g., , with
, where is a scalar,
is a four-vector, and is the four-momentum. As a simple example, we
calculate the relativistic power law for a dilute charged gas under
the action of an electromagnetic field . All standard results are
readly recovered in the particular limit .Comment: 7 pages; to be published in EPJ
- …