“NA REALIDADE, PORTUGAL, MOÇAMBIQUE, BRASIL... EU LIGO MUITO À IDEIA DE NAÇÃO PORTUGUESA”: LIGAR O QUE A VIDA SEPAROU.

O texto tem por base uma etnografia realizada com três gerações de três famílias que integraram as elites coloniais portuguesas: a primeira geração partiu de Portugal, nos anos 1950/60, para viver em Moçambique e daí partiu, depois de 1974, para o Brasil, onde já nasceram os membros da terceira geração. Pretende contribuir para uma concepção da noção de diáspora sustentada na observação das práticas e das representações de pessoas concretas em situações de deslocação espacial tam- bém elas concretas. Para tal faz um entrosamento entre a discussão académica que tem envolvido a noção nas últimas décadas e a ideia de diáspora agenciada pelos membros das famílias estudadas (“diáspora colonial”). Termina afirmando que os conteúdos que lhe são atribuídos estão relacionados com as condições objetivas e subjetivas dos percursos experimentados por quem os convoca. No final, o texto abor- da o papel que os objetos deslocados assumem na construção da ideia de diáspora.

Search for gravitational wave ringdowns from perturbed intermediate mass black holes in LIGO-Virgo data from 2005-2010

We report results from a search for gravitational waves produced by perturbed intermediate mass black holes ( IMBH) in data collected by LIGO and Virgo between 2005 and 2010. The search was sensitive to astrophysical sources that produced damped sinusoid gravitational wave signals, also known as ringdowns, with frequency 50 <= f(0)/Hz <= 2000 and decay timescale 0.0001 less than or similar to tau/s less than or similar to 0.1 characteristic of those produced in mergers of IMBH pairs. No significant gravitational wave candidate was detected. We report upper limits on the astrophysical coalescence rates of IMBHs with total binary mass 50 <= M/ M circle dot <= 450 and component mass ratios of either 1: 1 or 4: 1. For systems with total mass 100 <= M/M circle dot <= 150, we report a 90% confidence upper limit on the rate of binary IMBH mergers with nonspinning and equal mass components of 6.9 x 10(-8) Mpc(-3) yr(-1). We also report a rate upper limit for ringdown waveforms from perturbed IMBHs, radiating 1% of their mass as gravitational waves in the fundamental, l = m = 2, oscillation mode, that is nearly three orders of magnitude more stringent than previous results.

Methods and results of a search for gravitational waves associated with gamma-ray bursts using the GEO 600, LIGO, and Virgo detectors

In this paper we report on a search for short-duration gravitational wave bursts in the frequency range 64 Hz-1792 Hz associated with gamma-ray bursts (GRBs), using data from GEO 600 and one of the LIGO or Virgo detectors. We introduce the method of a linear search grid to analyze GRB events with large sky localization uncertainties, for example the localizations provided by the Fermi Gamma-ray Burst Monitor (GBM). Coherent searches for gravitational waves (GWs) can be computationally intensive when the GRB sky position is not well localized, due to the corrections required for the difference in arrival time between detectors. Using a linear search grid we are able to reduce the computational cost of the analysis by a factor of O(10) for GBM events. Furthermore, we demonstrate that our analysis pipeline can improve upon the sky localization of GRBs detected by the GBM, if a high-frequency GW signal is observed in coincidence. We use the method of the linear grid in a search for GWs associated with 129 GRBs observed satellite-based gamma-ray experiments between 2006 and 2011. The GRBs in our sample had not been previously analyzed for GW counterparts. A fraction of our GRB events are analyzed using data from GEO 600 while the detector was using squeezed-light states to improve its sensitivity; this is the first search for GWs using data from a squeezed-light interferometric observatory. We find no evidence for GW signals, either with any individual GRB in this sample or with the population as a whole. For each GRB we place lower bounds on the distance to the progenitor, under an assumption of a fixed GW emission energy of 10(-2)M circle dot c(2), with a median exclusion distance of 0.8 Mpc for emission at 500 Hz and 0.3 Mpc at 1 kHz. The reduced computational cost associated with a linear search grid will enable rapid searches for GWs associated with Fermi GBM events once the advanced LIGO and Virgo detectors begin operation.

Search for gravitational radiation from intermediate mass black hole binaries in data from the second LIGO-Virgo joint science run

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%.

Multimessenger search for sources of gravitational waves and high-energy neutrinos: Initial results for LIGO-Virgo and IceCube

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.

Improved Upper Limits on the Stochastic Gravitational-Wave Background from 2009-2010 LIGO and Virgo Data

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.

Directed search for gravitational waves from Scorpius X-1 with initial LIGO data

We present results of a search for continuously emitted gravitational radiation, directed at the brightest low-mass x-ray binary, Scorpius X-1. Our semicoherent analysis covers 10 days of LIGO S5 data ranging from 50-550 Hz, and performs an incoherent sum of coherent F-statistic power distributed amongst frequency-modulated orbital sidebands. All candidates not removed at the veto stage were found to be consistent with noise at a 1% false alarm rate. We present Bayesian 95% confidence upper limits on gravitational-wave strain amplitude using two different prior distributions: a standard one, with no a priori assumptions about the orientation of Scorpius X-1; and an angle-restricted one, using a prior derived from electromagnetic observations. Median strain upper limits of 1.3 x 10(-24) and 8 x 10(-25) are reported at 150 Hz for the standard and angle-restricted searches respectively. This proof-of-principle analysis was limited to a short observation time by unknown effects of accretion on the intrinsic spin frequency of the neutron star, but improves upon previous upper limits by factors of similar to 1.4 for the standard, and 2.3 for the angle-restricted search at the sensitive region of the detector.

Advanced LIGO

The Advanced LIGO gravitational wave detectors are second-generation instruments designed and built for the two LIGO observatories in Hanford, WA and Livingston, LA, USA. The two instruments are identical in design, and are specialized versions of a Michelson interferometer with 4 km long arms. As in Initial LIGO, Fabry-Perot cavities are used in the arms to increase the interaction time with a gravitational wave, and power recycling is used to increase the effective laser power. Signal recycling has been added in Advanced LIGO to improve the frequency response. In the most sensitive frequency region around 100 Hz, the design strain sensitivity is a factor of 10 better than Initial LIGO. In addition, the low frequency end of the sensitivity band is moved from 40 Hz down to 10 Hz. All interferometer components have been replaced with improved technologies to achieve this sensitivity gain. Much better seismic isolation and test mass suspensions are responsible for the gains at lower frequencies. Higher laser power, larger test masses and improved mirror coatings lead to the improved sensitivity at mid and high frequencies. Data collecting runs with these new instruments are planned to begin in mid-2015.

Le onde gravitazionali: dalla geometria differenziale al LIGO

Le onde gravitazionali, la cui prima osservazione diretta risale al 2015, sono una delle predizioni più importanti della Relatività Generale di Einstein. In questo lavoro di tesi triennale si vuole fornire uno studio approfondito di tale fenomeno. A tale scopo la trattazione è stata suddivisa in tre capitoli: Nel primo capitolo si getteranno le basi della geometria differenziale, fondamentale per la formulazione della Relatività Generale, introducendo tutte le nozioni ed i teoremi fondamentali per questa teoria. Nel secondo introdurremo i principi alla base della formulazione della teoria della Relatività Generale. Successivamente scriveremo le equazioni di campo di Einstein e ne ricaveremo una prima soluzione esatta (la soluzione di Schwarzschild). Grazie alle conoscenze che verranno introdotte nei primi due capitoli, nell'ultimo potremo studiare in dettaglio il fenomeno delle onde gravitazionali: come si ricavano a partire dalle equazioni di Einsten, come si propagano, come interagiscono con la materia, come si possono rilevare, ...

Gravitational signature of Schwarzschild black holes in dynamical Chern-Simons gravity

Dynamical Chern-Simons gravity is an extension of general relativity in which the gravitational field is coupled to a scalar field through a parity-violating Chern-Simons term. In this framework, we study perturbations of spherically symmetric black hole spacetimes, assuming that the background scalar field vanishes. Our results suggest that these spacetimes are stable, and small perturbations die away as a ringdown. However, in contrast to standard general relativity, the gravitational waveforms are also driven by the scalar field. Thus, the gravitational oscillation modes of black holes carry imprints of the coupling to the scalar field. This is a smoking gun for Chern-Simons theory and could be tested with gravitational-wave detectors, such as LIGO or LISA. For negative values of the coupling constant, ghosts are known to arise, and we explicitly verify their appearance numerically. Our results are validated using both time evolution and frequency domain methods.

Sintomas depressivos e prejuízo funcional de idosos de um Centro-Dia Geriátrico

OBJETIVOS: Caracterizar idosos do Centro-Dia Geriátrico de Rio Claro (SP) de acordo com os sintomas depressivos e o prejuízo funcional e, ainda, verificar a relação entre sintomas depressivos e desempenho nas atividades instrumentais da vida diária. MÉTODOS: Estudo descritivo, transversal, do qual participaram 36 idosos. Os instrumentos utilizados foram: anamnese, Escala Geriátrica de Depressão e Questionário de Atividades Instrumentais de Pfeffer. A análise dos dados ocorreu por meio da estatística descritiva e dos testes U de Mann-Whi-t-ney e correlação de Spearman, com nível de significância de 5%. RESULTADOS: Houve maior presença de mulheres na amostra, que apresentou em média 77,02 anos de idade e 3,44 anos de estudo. A prevalência de sintomas depressivos e prejuízo funcional foi de 30,5% e 63,8%, respectivamente, sendo maior entre as mulheres. Não houve diferença significativa entre as variáveis analisadas em comparação aos gêneros e às faixas etárias. O teste de correlação de Spearman apresentou rho = 0,38 e p = 0,02, indicando correlação positiva, porém fraca, entre sintomas depressivos e prejuízo funcional. CONCLUSÃO: Conclui-se que há uma baixa relação entre as variáveis sintomas depressivos e prejuízo funcional, sendo necessários novos estudos para investigar outros fatores que podem estar relacionados a essas variáveis.

Mineralização de nitrogênio em solo tropical tratado com lodos de esgoto

A mineralização do N orgânico é um dos principais fatores que determinam as quantidades de lodos de esgoto (LE) a aplicar em solos. O objetivo deste trabalho foi quantificar, em laboratório, o potencial de mineralização de N orgânico num Latossolo Vermelho distroférrico, tratado com dois LE anaeróbios, um de origem estritamente urbana (Franca, SP) e outro com presença de despejos industriais (Barueri, SP). Os LE foram aplicados ao solo em doses de 1,5, 3, 6 e 12 g kg-1 (Franca) e 4, 8, 16 e 32 g kg-1 (Barueri), e o tempo de incubação foi de 15 semanas. O acúmulo de N inorgânico no solo ao final da incubação foi proporcional às quantidades de N orgânico adicionadas. O potencial de mineralização estimado pelo modelo exponencial simples foi de 24 mg kg-1 de N no solo sem lodo, e variou entre 44 e 265 mg kg-1 de N no solo tratado com os lodos. A fração de mineralização potencial do N orgânico dos lodos foi estimada em 31%. A mineralização foi mais lenta no solo tratado com as duas maiores doses do LE de Barueri. Os dois lodos acidificaram o solo; o de Franca causou acidificação mais intensa que o de Barueri.

Chemical similarity among domesticated and wild genotypes of peanut based on n-alkanes profiles

The objective of this work was to analyze the epicuticular n-alkane profile of domesticated and wild peanut genotypes. Foliar epicuticular n-alkanes of four Arachis hypogaea genotypes and two wild species - A. monticola and A. stenosperma - were analyzed by gas chromatography. Chemical relationships between them were evaluated using the Dice coefficient and UPGMA method. Two clusters were formed: one with four A. hypogaea genotypes and the other with the two wild species. There is more similarity between the BR1 and LIGO-PE06 genotypes and between the BRS 151 L-7 and BRS Havana genotypes.