ABSTRACT
We present an analysis of the individual pulses of four rotating radio transients (RRATs), previously discovered in a monitoring survey running for 5.5 yr at the frequency of 111 MHz. At a ...time interval equivalent to 5 d of continuous observations for each RRAT, 90, 389, 206 and 157 pulses were detected in J0640+07, J1005+30, J1132+25 and J1336+33, respectively. The investigated RRATs have different distributions of their pulse amplitudes. For J0640+07 and J1132+25, the distribution is described by a single exponent over the entire range of flux densities. For J1005+30 and J1336+33, it is a lognormal function with a power-law tail. For J0640+07 and J1005+30, we have detected pulses with a signal-to-noise ratio (S/N) of a few hundred. For J1132+25 and J1336+33, the S/N of the strongest pulses reaches several tens. These RRATs show a strong change in their emission. When the strengths of their pulse amplitudes are significantly changed, we see long intervals of absence of emission or its strong attenuation. The analysis carried out in this work shows that it is possible that all the studied RRATs are, apparently, pulsars with giant pulses.
ABSTRACT
Studies of the pulsar B0823+26 have been carried out using the Large Phased Array (LPA) radio telescope. At a time span of 5.5 yr, the amplitudes of the main pulse (MP), postcursor (PC), and ...interpulse (IP) were evaluated in daily sessions lasting 3.7 min. It is shown that the ratio of the average amplitudes of MP in the bright (B) and quiet (Q) modes is 60. For B-mode, the average ratio of MP amplitudes to IP amplitudes is 65, and the ratio of MP amplitudes to PC amplitudes is 28. The number of sessions with a nulling is 4 per cent of the total number of sessions. Structure function (SF) and correlation function analysis of MP, IP, and PC amplitude variations of over a long-time interval allowed us to detect typical time scales 37 ± 5 d and one year. The analysis of time variations shows that the time scale of 37 d is well explained by refraction on inhomogeneities of interstellar plasma, which is distributed mostly quasi-uniformly in the line of sight. This scintillation makes the main contribution to the observed variability. Analysis of the structure function showed that there may be a few days variability. This time scale does not have an unambiguous interpretation but is apparently associated with the refraction of radio waves on the interstellar medium. One-year variability time scale has not been previously detected. We associate its appearance with the presence of a scattering layer on a closely located screen at a distance of about 50–100 pc from the Earth.
The Department of Energy (DOE) Joint Genome Institute (JGI) is a national user facility with massive-scale DNA sequencing and analysis capabilities dedicated to advancing genomics for bioenergy and ...environmental applications. Beyond generating tens of trillions of DNA bases annually, the Institute develops and maintains data management systems and specialized analytical capabilities to manage and interpret complex genomic data sets, and to enable an expanding community of users around the world to analyze these data in different contexts over the web. The JGI Genome Portal (http://genome.jgi.doe.gov) provides a unified access point to all JGI genomic databases and analytical tools. A user can find all DOE JGI sequencing projects and their status, search for and download assemblies and annotations of sequenced genomes, and interactively explore those genomes and compare them with other sequenced microbes, fungi, plants or metagenomes using specialized systems tailored to each particular class of organisms. We describe here the general organization of the Genome Portal and the most recent addition, MycoCosm (http://jgi.doe.gov/fungi), a new integrated fungal genomics resource.
A series of 100th anniversaries of recent years (the First World War, the Revolution of 1917, the Russian Civil War, the introduction of the NEP) has stimulated historians and representatives of ...related sciences (sociologists, philosophers, political scientists, culturologists, economic historians, etc.) to summarize the study of this turning point for the national history of the period, which is increasingly often regarded as homogeneous (“the time of wars and revolutions”), as well as its immediate consequences, stretching back to the 1920s and 1930s. The works published within the framework of the anniversaries and the discussions that flared up around them more clearly exposed the least studied and controversial aspects of the problems and made it possible to identify urgent tasks for the future. Quite expectedly, the focus was on subjects such as rethinking the causes of the revolutionary events and the role of various social groups in them; comparison of the events of February and October 1917, the degree of discontinuity and continuity of processes and the existence of alternative ways of Russia’s development; characteristics of the armed forces and political movements opposed to the Bolsheviks; the relation of “red” and “white” terror; problems of social stratification in postrevolutionary Russia and the relationship between the concepts of
former people, the socially alien, economically dangerous elements, NEPmen
; etc. In addition, summarizing the results of studying the revolution and its consequences has contributed to the revival of conceptual discussions about totalitarianism, the social base of the Soviet regime of the 1920s−1930s, and the features of the formation of civil society in Russia, as well as about the conditions for the formation and specifics of the “welfare state” of the Soviet type. At the same time, one should admit that the problem of the social policy of the Bolsheviks, which directly relates to many of the above conceptual or debatable issues, remained practically outside the framework of scientific, historical, and political discussions. Meanwhile, for example, the outcome of the Civil War and the further fate of Russia were largely determined by the nature and priorities of the social policy of the warring parties, the degree of the attractiveness of their slogans for ordinary people in the rear and at the front, as well as the ability to bring these slogans to life. The problems of continuity with the pre-Soviet past of the country, the novelty and relevance for society of the Bolsheviks’ transformations in the social sphere, and their compliance with the global trends of the era also seem key to understanding many debatable issues of early Soviet history. In particular, it is impossible to answer the question about the presence or absence of elements of civil society and the so-called “welfare state” in Soviet Russia without an objective assessment of the social slogans declared by the state and the methods of their implementation, as well as the nature of the interaction between the authorities and society in solving certain topical tasks.
ABSTRACT
Pulses from 16 previously known rotating radio transients (RRATs) have been searched for with the 111 MHz daily monitoring program for 4 to 5.5 yr using the Large Phased Array (LPA) at ...Pushchino. The total number of pulses detected in such a long observation interval is only 90 for RRAT J0640+07, but is as high as 10 751 for RRAT J0302+22. The number and amplitude of pulses vary on time-scales from 6 to 20 months for RRATs J1336+33, J1404+11, J1848+15, J2051+12 and J2105+22, and the pulse number can increase by one or two orders of magnitude in active phases. Long-term trends are found for RRATs J0139+33 and J0302+22, which show a 2–3 times increase in detected pulse number over 1959 d. Some RRATs show annual variations in both pulse number and pulse amplitude. It is hard to explain all these variation time-scales by refractive scintillation on the interstellar medium. The annual and semi-annual variations are probably caused by scintillations on the inhomogeneous interplanetary plasma. Our data show that the number of observational sessions with no pulse detection over the threshold decreases exponentially with the length of pulse silence.
The paper examines the role of education in economic development from both a theoretical and a historic perspective, addresses why education has been the limiting factor of sustainable development. ...Educated workers raise national income directly and productivity of labour. This paper shows the impact of human capital development on economic growth in national economy through educational environment of universities in condition technosphere safety. In the study recommended that government would guarantee quality education environment of universities for development of innovation economy. Government should also commit more funds to enhance human capital development and environmental protection.
We have analyzed two-dimensional correlation functions from the dynamic spectra of 11 pulsars using the archival data of the “Radioastron” project. The time-sections of these functions were ...approximated by exponential functions with a power
. It is shown that this approximation describes the shape of the correlation function much better than the Gaussian. The temporal structure function
for small values of the delay
is a power law with an index
. The spectrum power of spatial inhomogeneities of the interstellar plasma is related to the power of the structure function as
. We have determined the characteristic scintillation time and the power
in the direction of 11 pulsars. In the direction of three pulsars (B0329+54, B0823+26, and B1929+10), the spectrum power of spatial inhomogeneities of the interstellar plasma turned out to be very close to the value for the Kolmogorov spectrum (
). For other pulsars, it ranges from 3.18 to 3.86. It is shown that the measured scintillation parameters are significantly influenced by the duration of the observation session, expressed by its ratio to the characteristic scintillation time. If this parameter is less than 10, the parameter estimates may be biased: the values of
and the characteristic scintillation time
may decrease.
The Genomes OnLine Database (GOLD, http://www.genomesonline.org/) is a comprehensive resource for centralized monitoring of genome and metagenome projects worldwide. Both complete and ongoing ...projects, along with their associated metadata, can be accessed in GOLD through precomputed tables and a search page. As of September 2011, GOLD, now on version 4.0, contains information for 11 472 sequencing projects, of which 2907 have been completed and their sequence data has been deposited in a public repository. Out of these complete projects, 1918 are finished and 989 are permanent drafts. Moreover, GOLD contains information for 340 metagenome studies associated with 1927 metagenome samples. GOLD continues to expand, moving toward the goal of providing the most comprehensive repository of metadata information related to the projects and their organisms/environments in accordance with the Minimum Information about any (x) Sequence specification and beyond.
ABSTRACT
We report on slow phase variations of the response of the space-ground radio interferometer RadioAstron during observations of pulsar B0329+54. The phase variations are due to the ionosphere ...and clearly distinguishable from effects of interstellar scintillation. Observations were made in a frequency range of 316–332 MHz with the 110-m Green Bank Telescope and the 10-m RadioAstron telescope in 1-h sessions on 2012 November 26, 27, 28, and 29 with progressively increasing baseline projections of about 60, 90, 180, and 240 thousand kilometres. Quasi-periodic phase variations of interferometric scintles were detected in two observing sessions with characteristic time-scales of 12 and 10 min and amplitudes of up to 6.9 radians. We attribute the variations to the influence of medium-scale Travelling Ionospheric Disturbances. The measured amplitude corresponds to variations in vertical total electron content in ionosphere of about $0.1\times 10^{16}\, \text{m}^{-2}$. Such variations would noticeably constrain the coherent integration time in VLBI studies of compact radio sources at low frequencies.
ABSTRACT
The drift periods P2 and P3 were searched for using the summed power spectra of 41 pulsars observed at declinations from −9° to +42°. The power spectra of pulses with a given period, pulse ...width, and drift behaviour have been simulated, the applicability of such a method for estimating drift parameters is shown. For most pulsars, the distribution of harmonic amplitudes in the power spectra corresponds to the expected distribution for these pulsars without drift. At the same time, it was found that for a number of sources, the summed power spectra accumulated over a long period of time give the same drift parameters as those determined by other methods. For 11 pulsars we have defined or redefined the drift period P2. For eight sources the drift period P3 has been determined or redefined. The drift direction of subpulses was redefined for them.
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