75 research outputs found
Certain features of using modified collagen-containing raw materials with prolonged shelf life in food technology
In the current circumstances, trends in nutrition of a person striving to lead a healthy life-style require intake of meat products with the reduced energy value, minimal amounts of fat, increased protein mass fraction, presence of substances improving homeostasis of the body. The synergism of the modern nutrition science and meat industry enables creating food products that satisfy consumers’ demand. Today, in the Russian Federation, a theoretical and practical base of the technology development has been collected to the full extent in the field of rational processing of secondary raw materials in the food industry, optimal use of animal secondary raw materials, study of the protein ingredients of animal and plant origin and their deep scientifically substantiated processing, improvement of technological processes and equipment, and correspondently, product range extension. The paper broadens the information about the modified collagen-containing raw materials (cattle rumen), examines physico-chemical characteristics of the collagen-containing raw material and its changes in the process of freeze-drying with a special attention paid to the study of changes in the histological structure. The presence of the relatively uniform fibrillar structure was determined, which facilitated discovering the functional potential of proteinoids that form the fibrillar matrix in the composition of products from different groups. Analysis of IR-spectra revealed several significant absorption bands linked with the state of peptide bonds. The character of bands is linked with the complex of valence and deformation vibrations of the N- and С- types. It is believed that IR-spectra reflect conformations in the protein secondary structure, which suggests preserving properties of the tropocollagen particle or collagen molecule. Freeze-dried modified collagen-containing cattle rumen was tested by the example of jellies. The obtained databank broadens information about physico-chemical properties of modified collagen-containing raw materials (cattle rumen).In the current circumstances, trends in nutrition of a person striving to lead a healthy life-style require intake of meat products with the reduced energy value, minimal amounts of fat, increased protein mass fraction, presence of substances improving homeostasis of the body. The synergism of the modern nutrition science and meat industry enables creating food products that satisfy consumers’ demand. Today, in the Russian Federation, a theoretical and practical base of the technology development has been collected to the full extent in the field of rational processing of secondary raw materials in the food industry, optimal use of animal secondary raw materials, study of the protein ingredients of animal and plant origin and their deep scientifically substantiated processing, improvement of technological processes and equipment, and correspondently, product range extension. The paper broadens the information about the modified collagen-containing raw materials (cattle rumen), examines physico-chemical characteristics of the collagen-containing raw material and its changes in the process of freeze-drying with a special attention paid to the study of changes in the histological structure. The presence of the relatively uniform fibrillar structure was determined, which facilitated discovering the functional potential of proteinoids that form the fibrillar matrix in the composition of products from different groups. Analysis of IR-spectra revealed several significant absorption bands linked with the state of peptide bonds. The character of bands is linked with the complex of valence and deformation vibrations of the N- and С- types. It is believed that IR-spectra reflect conformations in the protein secondary structure, which suggests preserving properties of the tropocollagen particle or collagen molecule. Freeze-dried modified collagen-containing cattle rumen was tested by the example of jellies. The obtained databank broadens information about physico-chemical properties of modified collagen-containing raw materials (cattle rumen)
Optical Photometry of Type II-P Supernova 2004dj in NGC 2403
We present photometric data of the type II-P supernova (SN) 2004dj in NGC
2403. The multicolor light curves cover the SN from 60 to 200 days after
explosion, and are measured with a set of intermediate-band filters that have
the advantage of tracing the strength variations of some spectral features. The
light curves show a flat evolution in the middle of the plateau phase, then
decline exponentially at the late times, with a rate of 0.100.03 mag (10
days) in most of the filters. In the nebular phase, the spectral energy
distribution (SED) of SN 2004dj shows a steady increase in the flux near 6600
\AA and 8500 \AA, which may correspond to the emission lines of H and
Ca II near-IR triplet, respectively. The photometric behavior suggests that SN
2004dj is a normal SN II-P. Compared with the light curves of another typical
SN II-P 1999em, we estimate the explosion date to be June 1021 UT, 2004
(JD 245316721) for SN 2004dj. We also estimate the ejected nickel mass
during the explosion to be = 0.023 0.005
from two different methods, which is typical for a SN II-P. We derive the
explosion energy erg, the ejecta
mass , and the initial radius for the presupernova star of SN 2004dj,
which are consistent with other typical SNe II-P.Comment: 15 pages, 9 figures, accepted for publication in A
A very low mass of Ni-56 in the ejecta of SN 1994W
We present spectroscopic and photometric observations of the luminous narrow-
line Type IIP (plateau) supernova 1994W. After the plateau phase (t >120 days),
the light curve dropped by 3.5 mag in V in only 12 days. Between 125 and 197
days after explosion the supernova faded substantially faster than the decay
rate of Co-56, and by day 197 it was 3.6 magnitudes less luminous in R compared
to SN 1987A. The low R-luminosity could indicate less than 0.0026 {+0.0017}/
{-0.0011} Msun of Ni-56 ejected at the explosion, but the emission between 125
and 197 days must then have been dominated by an additional power source, pre-
sumably circumstellar interaction. Alternatively, the late light curve was
dominated by Co-56 decay. In this case, the mass of the ejected Ni-56 was 0.015
{+0.012}/{-0.008} Msun, and the rapid fading between 125 and 197 days was most
likely due to dust formation. Though this value of the mass is higher than in
the case with the additional power source, it is still lower than estimated for
any previous Type II supernova. Only progenitors with M(ZAMS) = 8-10 Msun and
M(ZAMS) > 25 Msun are expected to eject such low masses of Ni-56. If M(ZAMS) =
8-10 Msun, the plateau phase indicates a low explosion energy, while for a
progenitor with M(ZAMS) > 25 Msun the energy can be the canonical 1.0E{51}
ergs. As SN 1994W was unusually luminous, the low-mass explosion may require an
uncomfortably high efficiency in converting explosion energy into radiation.
This favors a M(ZAMS) > 25 Msun progenitor. The supernova's narrow (roughly
1000 km s^{-1}) emission lines were excited by the hot supernova spectrum,
rather than a circumstellar shock. The thin shell from which the lines origi-
nated was most likely accelerated by the radiation from the supernova.Comment: 19 pages AASTeX v.4.0, including 5 Postscript figures; ApJ, in pres
Observations and analysis of two type IIP supernovae: the intrinsically faint object SN 2005cs and the ambiguous object SN 2005ay
Aims: To derive observational properties and physical parameters of the
progenitor stars of type IIP supernovae SN 2005ay and SN 2005cs from their
U,B,V,R,I CCD photometry, and to define their velocity behaviour. Methods:
Light curves are analysed, and the velocities and spectral characteristics of
SN 2005cs are obtained using synthetic spectra modeling. Results: Both
supernovae are found to be fainter than the average
SN IIP, with SN 2005cs being more subluminous and showing slight brightening
in the second half of plateau stage in the
V,R,I bands and a low expansion velocity.
The effects of two different plausible distance moduli on the derived
physical parameters of SN 2005ay are considered.
Two approaches are used to recover the amounts of the ejected 56Ni,
indicating masses of the order of
0.02 Msun, although late luminosities might indicate a higher amount for SN
2005ay, especially for the large distance case.
Constraints on the progenitor properties are also presented, based on
empirical analytical models. Two approaches are used to estimate the expansion
velocities at the middle of the plateau phase. SN 2005cs represents an example
of where all 3 physical parameters, velocity, energy and 56Ni mass are lower
than average, a correlation not always observed in SNe IIP. SN 2005ay may
belong to the same class if the shorter distance possibility is adopted.
Furthermore, the estimated mass range for SN 2005cs is in agreement with limits
established by using pre-supernova imaging.Comment: 8 pages, 6 figures, to be published in A&A vol.460, issue 3, December
200
Antioxidants of Belgorod State University Botanical Garden Plants: Ribes Aureum Fruits Anthocyanins
According to the results of the study, it was found that currant berries of this species contain four main anthocyanins: delfinidin-3-glucoside, delfinidin-3-rutinroside, cyanidin-3-glucoside and cyanidin-3-rutinosid
Isospin Character of the Pygmy Dipole Resonance in 124Sn
The pygmy dipole resonance has been studied in the proton-magic nucleus 124Sn
with the (a,a'g) coincidence method at E=136 MeV. The comparison with results
of photon-scattering experiments reveals a splitting into two components with
different structure: one group of states which is excited in (a,a'g) as well as
in (g,g') reactions and a group of states at higher energies which is only
excited in (g,g') reactions. Calculations with the self-consistent relativistic
quasiparticle time-blocking approximation and the quasiparticle phonon model
are in qualitative agreement with the experimental results and predict a
low-lying isoscalar component dominated by neutron-skin oscillations and a
higher-lying more isovector component on the tail of the giant dipole
resonance
The effect of quercetin on oxidative stress markers and mitochondrial permeability transition in the heart of rats with type 2 diabetes
Increasing evidence suggests that oxidative stress and induction of mitochondrial permeability transition in cardiomyocytes are linked to tissue damage and the development of diabetic cardiovascular complications. The aim of this study was to assess the effects of quercetin (Q) on oxidative stress and mitochondrial permeability transition in the heart of rats with type 2 diabetes mellitus (DM). Type 2 DM was induced in 12-week-old male Wistar rats by intraperitoneal injections of 25 mg/kg streptozotocin twice per week followed by a high-fat diet during four weeks. The rats were divided into three groups: control intact group (C, n = 8), untreated diabetic group (Diabetes, n = 8) and diabetic rats treated with Q (50 mg/kg/day per os for 8 weeks) after diabetes induction (Diabetes+Q, n = 8). Administration of Q increased insulin sensitivity and normalized the functional state of cardiac mitochondria due to increased aconitase and succinate dehydrogenase activities in rats with type 2 DM. Q also ameliorated oxidative stress, decreasing the level of advanced oxidation protein products and increasing the activity of thioredoxin-reductase in heart mitochondria of diabetic rats. In addition, Ca2+-induced opening of the mitochondrial permeability transition pore was significantly inhibited in diabetic rats treated with Q in comparison with the untreated diabetic group. These data demonstrate that Q can protect against oxidative stress, mitochondrial permeability transition induction and mitochondrial dysfunction in cardiomyocytes of diabetic rats. We suggest that the use of Q may contribute to the amelioration of cardiovascular risk in type 2 DM
Pygmy dipole resonance in 208Pb
Scattering of protons of several hundred MeV is a promising new spectroscopic
tool for the study of electric dipole strength in nuclei. A case study of 208Pb
shows that at very forward angles J^pi = 1- states are strongly populated via
Coulomb excitation. A separation from nuclear excitation of other modes is
achieved by a multipole decomposition analysis of the experimental cross
sections based on theoretical angular distributions calculated within the
quasiparticle-phonon model. The B(E1) transition strength distribution is
extracted for excitation energies up to 9 MeV, i.e., in the region of the
so-called pygmy dipole resonance (PDR). The Coulomb-nuclear interference shows
sensitivity to the underlying structure of the E1 transitions, which allows for
the first time an experimental extraction of the electromagnetic transition
strength and the energy centroid of the PDR.Comment: submitted to Phys. Rev.
Complete electric dipole response and the neutron skin in 208Pb
A benchmark experiment on 208Pb shows that polarized proton inelastic
scattering at very forward angles including 0{\deg} is a powerful tool for
high-resolution studies of electric dipole (E1) and spin magnetic dipole (M1)
modes in nuclei over a broad excitation energy range to test up-to-date nuclear
models. The extracted E1 polarizability leads to a neutron skin thickness
r_skin = 0.156+0.025-0.021 fm in 208Pb derived within a mean-field model [Phys.
Rev. C 81, 051303 (2010)], thereby constraining the symmetry energy and its
density dependence, relevant to the description of neutron stars.Comment: 5 pages, 5 figures, revised mansucrip
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