120 resultados para Marx


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We present an implementation of the F-statistic to carry out the first search in data from the Virgo laser interferometric gravitational wave detector for periodic gravitational waves from a priori unknown, isolated rotating neutron stars. We searched a frequency f(0) range from 100 Hz to 1 kHz and the frequency dependent spindown f(1) range from -1.6(f(0)/100 Hz) x 10(-9) Hz s(-1) to zero. A large part of this frequency-spindown space was unexplored by any of the all-sky searches published so far. Our method consisted of a coherent search over two-day periods using the F-statistic, followed by a search for coincidences among the candidates from the two-day segments. We have introduced a number of novel techniques and algorithms that allow the use of the fast Fourier transform (FFT) algorithm in the coherent part of the search resulting in a fifty-fold speed-up in computation of the F-statistic with respect to the algorithm used in the other pipelines. No significant gravitational wave signal was found. The sensitivity of the search was estimated by injecting signals into the data. In the most sensitive parts of the detector band more than 90% of signals would have been detected with dimensionless gravitational-wave amplitude greater than 5 x 10(-24).

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This paper reports on an unmodeled, all-sky search for gravitational waves from merging intermediate mass black hole binaries (IMBHB). The search was performed on data from the second joint science run of the LIGO and Virgo detectors (July 2009-October 2010) and was sensitive to IMBHBs with a range up to similar to 200 Mpc, averaged over the possible sky positions and inclinations of the binaries with respect to the line of sight. No significant candidate was found. Upper limits on the coalescence-rate density of nonspinning IMBHBs with total masses between 100 and 450 M-circle dot and mass ratios between 0.25 and 1 were placed by combining this analysis with an analogous search performed on data from the first LIGO-Virgo joint science run (November 2005-October 2007). The most stringent limit was set for systems consisting of two 88 M-circle dot black holes and is equal to 0.12 Mpc(-3) Myr(-1) at the 90% confidence level. This paper also presents the first estimate, for the case of an unmodeled analysis, of the impact on the search range of IMBHB spin configurations: the visible volume for IMBHBs with nonspinning components is roughly doubled for a population of IMBHBs with spins aligned with the binary's orbital angular momentum and uniformly distributed in the dimensionless spin parameter up to 0.8, whereas an analogous population with antialigned spins decreases the visible volume by similar to 20%.

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We present the first results of an all-sky search for continuous gravitational waves from unknown spinning neutron stars in binary systems using LIGO and Virgo data. Using a specially developed analysis program, the TwoSpect algorithm, the search was carried out on data from the sixth LIGO science run and the second and third Virgo science runs. The search covers a range of frequencies from 20 Hz to 520 Hz, a range of orbital periods from 2 to similar to 2,254 h and a frequency-and period-dependent range of frequency modulation depths from 0.277 to 100 mHz. This corresponds to a range of projected semimajor axes of the orbit from similar to 0.6 x 10(-3) ls to similar to 6,500 ls assuming the orbit of the binary is circular. While no plausible candidate gravitational wave events survive the pipeline, upper limits are set on the analyzed data. The most sensitive 95% confidence upper limit obtained on gravitational wave strain is 2.3 x 10(-24) at 217 Hz, assuming the source waves are circularly polarized. Although this search has been optimized for circular binary orbits, the upper limits obtained remain valid for orbital eccentricities as large as 0.9. In addition, upper limits are placed on continuous gravitational wave emission from the low-mass x-ray binary Scorpius X-1 between 20 Hz and 57.25 Hz.

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We report the results of a multimessenger search for coincident signals from the LIGO and Virgo gravitational-wave observatories and the partially completed IceCube high-energy neutrino detector, including periods of joint operation between 2007-2010. These include parts of the 2005-2007 run and the 2009-2010 run for LIGO-Virgo, and IceCube's observation periods with 22, 59 and 79 strings. We find no significant coincident events, and use the search results to derive upper limits on the rate of joint sources for a range of source emission parameters. For the optimistic assumption of gravitational-wave emission energy of 10(-2) M(circle dot)c(2) at similar to 150 Hz with similar to 60 ms duration, and high-energy neutrino emission of 1051 erg comparable to the isotropic gamma-ray energy of gamma-ray bursts, we limit the source rate below 1.6 x 10(-2) Mpc(-3) yr(-1). We also examine how combining information from gravitational waves and neutrinos will aid discovery in the advanced gravitational-wave detector era.

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Gravitational waves from a variety of sources are predicted to superpose to create a stochastic background. This background is expected to contain unique information from throughout the history of the Universe that is unavailable through standard electromagnetic observations, making its study of fundamental importance to understanding the evolution of the Universe. We carry out a search for the stochastic background with the latest data from the LIGO and Virgo detectors. Consistent with predictions from most stochastic gravitational-wave background models, the data display no evidence of a stochastic gravitational-wave signal. Assuming a gravitational-wave spectrum of Omega(GW)(f) = Omega(alpha)(f/f(ref))(alpha), we place 95% confidence level upper limits on the energy density of the background in each of four frequency bands spanning 41.5-1726 Hz. In the frequency band of 41.5-169.25 Hz for a spectral index of alpha = 0, we constrain the energy density of the stochastic background to be Omega(GW)(f) < 5.6 x 10(-6). For the 600-1000 Hz band, Omega(GW)(f) < 0.14(f/900 Hz)(3), a factor of 2.5 lower than the best previously reported upper limits. We find Omega(GW)(f) < 1.8 x 10(-4) using a spectral index of zero for 170-600 Hz and Omega(GW)(f) < 1.0(f/1300 Hz)(3) for 1000-1726 Hz, bands in which no previous direct limits have been placed. The limits in these four bands are the lowest direct measurements to date on the stochastic background. We discuss the implications of these results in light of the recent claim by the BICEP2 experiment of the possible evidence for inflationary gravitational waves.

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A eminência da Primeira Guerra Mundial efervesceu o debate entre teorias que buscavam explicar as causas e as conseqüências daqueles conflitos. Dentre os principais pensadores da época, Karl Kautsky, editor da revista Die Neue Zeit, era considerado o primeiro discípulo de Marx e Engels, exercendo, através de seus artigos, grande influência social. E foi no ano de 1914 que, através dos artigos O imperialismo e a Guerra, O ultraimperialismo e a Preparação para Paz, Kautsky definiu sua interpretação e expectativas em relação a aquele momento. O conteúdo desses artigos é de primordial relevância para estimar, observando o desenrolar do século XX, o quanto fez sentido suas interpretações. Assim, o objetivo é contribuir ao esclarecimento dos pensamentos deste autor, a fim de ajudar a entender a sociedade mundial contemporânea e o Brasil, quase um século depois de ter feito as publicações mencionadas

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São José dos Campos, cidade do interior paulista, possui aproximadamente 62% de sua área territorial definida por legislação como Área de Proteção Ambiental – APA. Um fragmento desse total é formado pelo Banhado (ampla área alagada com características naturais preservadas avistada de toda a região central) e pelo Parque Burle Marx ou, como é conhecido pela população, o Parque da Cidade. Esse Parque é estruturado por jardins de Roberto Burle Marx e construções assinadas pelo arquiteto modernista Rino Levi (a residência de Olivo Gomes, a usina de leite e o galpão gaivotas - utilizado para grandes feiras e eventos). Apesar da riqueza desse conjunto o parque não é utilizado pela população de forma efetiva. A proposta deste trabalho nasceu da análise feita acima e do fato que existe ampla área livre pronta a receber novos equipamentos públicos de forma a estimular a população a utilizar o parque de forma mais assídua. Um dos equipamentos propostos é uma nova biblioteca, já que a biblioteca da cidade carece de ampliação

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This study aims to identify the horizon of emancipation in Human Rights Education, using the philosophy of praxis as a theoretical framework, basing on authors as Tonet, Losurdo, Marx, and Saviani and Duarte, taking as a privileged locus analysis of the Plan National Human Rights Education (PNEDH, 2007). The discussion about the historical development of the movement of the struggles for human rights was a starting point to indicate how, in general, these struggles have been developing since the context of bourgeois revolutions. From there we tried to discuss how the prospect of citizenship has been treated within the Rights Education, the latter being a reflection of social movements' struggles for rights from the year 1980. Situating this movement within a larger movement on the issue of education in Brazil in the twentieth century, we tried to discuss the flags such as citizenship, the strengthening of civil society and creating a culture of rights as a goal of emancipation. Seeking to differentiate between citizenship as political emancipation and human emancipation, was placed the imperative to take the citizenship as a mediator and not as an endpoint in order to equip a culture of struggle for a classless society without exploitation of man by man

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Pós-graduação em Serviço Social - FCHS

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Pós-graduação em Serviço Social - FCHS

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Pós-graduação em Serviço Social - FCHS

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This paper describes the main steps in the study of Senna spectabilis, as part of our bioprospection studies, with the isolation of spectaline, cassine and other piperidine alkaloids, as well as the preparation of semi-synthetic analogues, and the studies of their pharmacological and toxicological properties, which led to the establishment of two candidate drugs for the treatment of Alzheimer disease.

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Pós-graduação em Educação Escolar - FCLAR