96 research outputs found
Detection of two new RRATs at 111 MHz
A search for pulse signals in a area with declinations of +52\degr <\delta
<+55\degr was carried out on the LPA LPI radio telescope. When processing ten
months of observations recorded in six frequency channels with a channel width
of 415 kHz and a total bandwidth of 2.5 MHz, 22 thousand events were found with
a pronounced dispersion delay of signals over frequency channels, i.e. having
signs of pulsar pulses. It turned out that the found pulses belong to four
known pulsars and two new rotating radio transients (RRATs). An additional
pulse search conducted in 32-channel data with a channel width of 78 kHz
revealed 8 pulses for the transient J0249+52 and 7 pulses for the transient
J0744+55. Periodic radiation of transients was not detected. The analysis of
observations shows that the found RRATs are most likely pulsars with nullings,
where the proportion of nulling is greater than 99.9\%.Comment: published in Astronomy Reports, translated by Yandex translator with
correction of scientific lexis, 5 pages, 2 figures, 1 tabl
Pushchino multibeams pulsar search. IV. Detection of new pulsars at declinations -9o < \delta < +55o
The search for pulsars in monitoring data obtained at the radio telescope
Large Phased Array (LPA) at a frequency of 111 MHz was carried out. Daily
round-the-clock observations were carried out for about 3,000 days. The
duration of the observation session for each direction in the sky was 3.5
minutes per day. The search for pulsars was carried out using power spectra. To
search for weak pulsars, power spectra were summed up. The expected increase in
sensitivity was 35-40 times compared to observations in one session. In a blind
search, 330 pulsars with regular radiation were detected, with periods (P) from
0.0333 to 3.7455 s and dispersion measures (DM) up to 249 pc/cm3. 39 pulsars
turned out to be new. Average profiles were obtained for 6 pulsars. The DM for
7 pulsars previously detected on the LPA have been clarified.Comment: published in MNRAS, 13 pages, 4 figures, 4 tables, 4 appendixe
Proton configurations in the hydrogen bonds of KH2PO4 as seen by resonant x-ray diffraction
KH2PO4 (KDP) belongs to the class of hydrogen-bonded ferroelectrics, whose
paraelectric to ferroelectric phase transition is driven by the ordering of the
protons in the hydrogen bonds. We demonstrate that forbidden reflections of
KDP, when measured at an x-ray absorption edge, are highly sensitive to the
asymmetry of proton configurations. The change of average symmetry caused by
the "freezing" of the protons during the phase transition is clearly evidenced.
In the paraelectric phase, we identify in the resonant spectra of the forbidden
reflections a contribution related to the transient proton configurations in
the hydrogen bonds, which violates the high average symmetry of the sites of
the resonant atoms. The analysis of the temperature dependence reveals a change
of relative probabilities of the different proton configurations. They follow
the Arrhenius law, and the activation energies of polar and Slater
configurations are 18.6 and 7.3 meV, respectively
Multifrequency Study of Giant Radio Pulses from the Crab Pulsar with the K5 VLBI Recording Terminal
Simultaneous multifrequency observations of the Crab pulsar giant pulses
(GPs) were performed with the 64-m Kalyazin radio telescope at four frequencies
0.6, 1.4, 2.2 and 8.3 GHz using the K5 VLBI recording terminal. The K5 terminal
provided continuous recording in 16 4-MHz wide frequency channels distributed
over 4 frequency bands. Several thousands of GPs were detected during about 6
hours of observations in two successive days in July 2005. Radio spectra of
single GPs were analysed at separate frequencies and over whole frequency
range. These spectra manifest notable modulation over frequency ranges,
, both on large () and small
() frequency scales. Cross-correlation analysis of
GPs at 2.2 GHz showed that their pulse shapes can be interpreted as an ensemble
of unresolved bursts grouped together at time scales of mcs being
well-correlated over a 60-MHz band. The corresponding GP cross-correlation
functions do not obey the predictions of the amplitude-modulated noise model of
Rickett (1975), thus indicating that unresolved components represent a small
number of elementary emitters.Comment: 22 pages, 11 figures, 3 tables, submitted to PAS
Detection of Five New RRATs at 111 MHz
Results of 111-MHz monitoring observations carried out on the Big Scanning
Antenna of the Pushchino Radio Astronomy Observatory during September 1-28,
2015 are presented. Fifty-four pulsating sources were detected at declinations
. Forty-seven of these are known pulsars, five are new
sources, and two are previously discovered transients. Estimates of the peak
flux densities and dispersion measures are presented or all these sources.Comment: published in Astronomy Report, translated by Yandex translator with
correction of scientific lexis, 8 pages, 2 figures, 3 table
Giant Pulses -- the Main Component of the Radio Emission of the Crab Pulsar
The paper presents an analysis of dual-polarization observations of the Crab
pulsar obtained on the 64-m Kalyazin radio telescope at 600 MHz with a time
resolution of 250 ns. A lower limit for the intensities of giant pulses is
estimated by assuming that the pulsar radio emission in the main pulse and
interpulse consists entirely of giant radio pulses; this yields estimates of
100 Jy and 35 Jy for the peak flux densities of giant pulses arising in the
main pulse and interpulse, respectively. This assumes that the normal radio
emission of the pulse occurs in the precursor pulse. In this case, the
longitudes of the giant radio pulses relative to the profile of the normal
radio emission turn out to be the same for the Crab pulsar and the millisecond
pulsar B1937+21, namely, the giant pulses arise at the trailing edge of the
profile of the normal radio emission. Analysis of the distribution of the
degree of circular polarization for the giant pulses suggests that they can
consist of a random mixture of nanopulses with 100% circular polarization of
either sign, with, on average, hundreds of such nanopulses within a single
giant pulse.Comment: 13 pages, 6 figures (originally published in Russian in
Astronomicheskii Zhurnal, 2006, vol. 83, No. 1, pp. 62-69) translated by
Denise Gabuzd
Effects of central administration of the human Tau proteinon the <i>Bdnf, Trkb, p75, Mapt, Bax</i> and <i>Bcl-2</i> genes expression in the mouse brain
Alzheimerβs disease is the most common form of dementia, affecting millions of people worldwide. Despite intensive work by many researchers, the mechanisms underlying Alzheimerβs disease development have not yet been elucidated. Recently, more studies have been directed to the investigation of the processes leading to the formation of neurofibrillary tangles consisting of hyperphosphorylated microtubule-associated Tau proteins. Pathological aggregation of this protein leads to the development of neurodegeneration associated with impaired neurogenesis and apoptosis. In the present study, the effects of central administration of aggregating human Tau protein on the expression of the Bdnf, Ntrk2, Ngfr, Mapt, Bax and Bcl-2 genes in the brain of C57Bl/6J mice were explored. It was found that five days after administration of the protein into the fourth lateral ventricle, significant changes occurred in the expression of the genes involved in apoptosis and neurogenesis regulation, e. g., a notable decrease in the mRNA level of the gene encoding the most important neurotrophic factor BDNF (brain-derived neurotrophic factor) was observed in the frontal cortex which could play an important role in neurodegeneration caused by pathological Tau protein aggregation. Central administration of the Tau protein did not affect the expression of the Ntrk2, Ngfr, Mapt, Bax and Bcl-2 genes in the frontal cortex and hippocampus. Concurrently, a significant decrease in the expression of the Mapt gene encoding endogenous mouse Tau protein was found in the cerebellum. However, no changes in the level or phosphorylation of the endogenous Tau protein were observed. Thus, central administration of aggregating human Tau protein decreases the expression of the Bdnf gene in the frontal cortex and the Mapt gene encoding endogenous mouse Tau protein in the cerebellum of C57Bl/6J mice
Clinical study a Small-bowel mucosal transglutaminase 2-specific IgA deposits for the Diagnostics and efficiency in treatment of Celiac disease - results and conclusion
In this study is investigated transglutaminase-2 specific mucosal IgA autoantibody deposits which determined from small-bowel mucosal biopsies in 18 untreated, 18 treated celiac disease patients and in 40 nonceliac controls. The presence of the deposits was compared with mucosal villous morphology celiac, serology and genetic markers. The analysis of results has shown high diagnostic efficiency of discovering subepithelial deposits mucosal transglutaminase-2 specific IgA autoantibody in the diagnostics and dietary monitoring of this disorderΠΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½Ρ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΠΏΠΎ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ ΡΡΠ±ΡΠΏΠΈΡΠ΅Π»ΠΈΠ°Π»ΡΠ½ΡΡ
Π΄Π΅ΠΏΠΎΠ·ΠΈΡΠΎΠ² ΡΠΊΠ°Π½Π΅Π²ΡΡ
ΡΡΠ°Π½ΡΠ³Π»ΡΡΠ°ΠΌΠΈΠ½Π°Π·Π½ΡΡ
Π°Π½ΡΠΈΡΠ΅Π» (IgA-tTG) Π² Π±ΠΈΠΎΠΏΡΠ°ΡΠ°Ρ
ΡΠ»ΠΈΠ·ΠΈΡΡΠΎΠΉ ΠΎΠ±ΠΎΠ»ΠΎΡΠΊΠΈ ΡΠΎΠ½ΠΊΠΎΠ³ΠΎ ΠΊΠΈΡΠ΅ΡΠ½ΠΈΠΊΠ° Ρ ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΎΠ² Π² ΡΠ°Π·Π½ΡΡ
Π³ΡΡΠΏΠΏΠ°Ρ
: Π²ΠΏΠ΅ΡΠ²ΡΠ΅ Π²ΡΡΠ²Π»Π΅Π½Π½Π°Ρ ΡΠ΅Π»ΠΈΠ°ΠΊΠΈΡ (18), Π±ΠΎΠ»ΡΠ½ΡΠ΅ ΡΠ΅Π»ΠΈΠ°ΠΊΠΈΠ΅ΠΉ, Π½Π°Ρ
ΠΎΠ΄ΡΡΠΈΠ΅ΡΡ Π½Π° Π»Π΅ΡΠ΅Π½ΠΈΠΈ (18) ΠΈ ΠΏΠ°ΡΠΈΠ΅Π½ΡΡ Π±Π΅Π· ΡΠ΅Π»ΠΈΠ°ΠΊΠΈΠΈ (40). ΠΡΠ΅ ΠΏΠ°ΡΠΈΠ΅Π½ΡΡ, ΠΎΠ΄Π½ΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΠΎ Ρ ΡΡΠ±ΡΠΏΠΈΡΠ΅Π»ΠΈΠ°Π»ΡΠ½ΡΠΌΠΈ Π΄Π΅ΠΏΠΎΠ·ΠΈΡΠ°ΠΌΠΈ ΡΠΊΠ°Π½Π΅Π²ΡΡ
ΡΡΠ°Π½ΡΠ³Π»ΡΡΠ°ΠΌΠΈΠ½Π°Π·Π½ΡΡ
Π°Π½ΡΠΈΡΠ΅Π», ΠΏΡΠΎΡΠ»ΠΈ ΠΎΠ±ΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΠ΅ Π½Π° ΡΡΠ²ΠΎΡΠΎΡΠΎΡΠ½ΡΠ΅, Π³Π΅Π½Π΅ΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΈ Π³ΠΈΡΡΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΌΠ°ΡΠΊΠ΅ΡΡ. ΠΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ Π΄Π°Π½Π½ΠΎΠ³ΠΎ ΠΌΠ΅ΡΠΎΠ΄Π° ΠΏΠΎΠΊΠ°Π·Π°Π»ΠΎ Π²ΡΡΠΎΠΊΡΡ Π΄ΠΈΠ°Π³Π½ΠΎΡΡΠΈΡΠ΅ΡΠΊΡΡ ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΡ Π²ΡΡΠ²Π»Π΅Π½ΠΈΡ ΡΡΠ±ΡΠΏΠΈΡΠ΅Π»ΠΈΠ°Π»ΡΠ½ΡΡ
Π΄Π΅ΠΏΠΎΠ·ΠΈΡΠΎΠ² ΡΠΊΠ°Π½Π΅Π²ΡΡ
ΡΡΠ°Π½ΡΠ³Π»ΡΡΠ°ΠΌΠΈΠ½Π°Π·Π½ΡΡ
Π°Π½ΡΠΈΡΠ΅Π» IgA-tTG Π΄Π»Ρ Π΄ΠΈΠ°Π³Π½ΠΎΡΡΠΈΠΊΠΈ ΡΠ΅Π»ΠΈΠ°ΠΊΠΈΠΈ ΠΈ ΠΌΠΎΠ½ΠΈΡΠΎΡΠΈΠ½Π³Π° ΠΏΠ°ΡΠΎΠ³Π΅Π½Π΅ΡΠΈΡΠ΅ΡΠΊΠΎΠΉ Π΄ΠΈΠ΅ΡΠΎΡΠ΅ΡΠ°ΠΏΠΈΠΈ
MEAT PRODUCTION IN RUSSIA: PROBLEMS OF IMPORT SUBSTITUTION
This article provides a feasibility study of the State program of agricultural development and regulation of agricultural products, raw materials and food for 2013-2020 in terms of production and import of meat products. To analyze the feasibility of the said State program has been used three tools: trend analysis of the key indicators, statistical regression analysis and production function. Proposed methodological approach and tools for expert evaluation of realizability of the State Program allowed us to determine its possible unrealizability as scheduled until 2020
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