Measurement of Wave Attenuation in Buried Plastic Water Distribution Pipes

Leaks in pipes are a common issue encountered in the water industry. Acoustic methods are generally successful in finding and locating leaks in metallic pipes, however, they are less effective when applied to plastic pipes. This is because leak-noise signals are heavily attenuated due to high damping in the pipe-wall and sound radiation into the soil. As result, high frequency leak noise does not travel long distances. To determine how far leak noise may travel in a pipe at any frequency, the attenuation of the wave responsible for leak noise propagation should be known. In this paper a new method to estimate this is described. The method is then applied to some measurements made on a bespoke pipe-test rig in the UK, and the results are compared with theoretical predictions.

Anomalous gauge couplings from composite Higgs and warped extra dimensions

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Measuring the Spin of Black Holes in Binary Systems Using Gravitational Waves

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Search for Gravitational Waves Associated with gamma-ray Bursts Detected by the Interplanetary Network

We present the results of a search for gravitational waves associated with 223 gamma-ray bursts (GRBs) detected by the InterPlanetary Network (IPN) in 2005-2010 during LIGO's fifth and sixth science runs and Virgo's first, second, and third science runs. The IPN satellites provide accurate times of the bursts and sky localizations that vary significantly from degree scale to hundreds of square degrees. We search for both a well-modeled binary coalescence signal, the favored progenitor model for short GRBs, and for generic, unmodeled gravitational wave bursts. Both searches use the event time and sky localization to improve the gravitational wave search sensitivity as compared to corresponding all-time, all-sky searches. We find no evidence of a gravitational wave signal associated with any of the IPN GRBs in the sample, nor do we find evidence for a population of weak gravitational wave signals associated with the GRBs. For all IPN-detected GRBs, for which a sufficient duration of quality gravitational wave data are available, we place lower bounds on the distance to the source in accordance with an optimistic assumption of gravitational wave emission energy of 10(-2)M(circle dot)c(2) at 150 Hz, and find a median of 13 Mpc. For the 27 short-hard GRBs we place 90% confidence exclusion distances to two source models: a binary neutron star coalescence, with a median distance of 12 Mpc, or the coalescence of a neutron star and black hole, with a median distance of 22 Mpc. Finally, we combine this search with previously published results to provide a population statement for GRB searches in first-generation LIGO and Virgo gravitational wave detectors and a resulting examination of prospects for the advanced gravitational wave detectors.

The use of radon (Rn-222) and volatile organic compounds in monitoring soil gas to localize NAPL contamination at a gas station in Rio Claro, Sao Paulo State, Brazil

This study focuses on the presence of radon (Rn-222) and volatile organic compounds (VOCs) in soil gases at a gas station located in the city of Rio Claro, Sao Paulo, Brazil, where a fossil fuel leak occurred. The spatial distribution results show a correlation between Rn-222 and VOCs, consistent with the fact that radon gas has a greater chemical affinity with organic phases than with water. This finding demonstrates that the presence of a residual hydrocarbon phase in an aquifer can retain radon, leading to a reduced radon content in the soil gas. The data in this study confirm the results of previous investigations, in which the method used in this study provided a preliminary fingerprint of a contaminated area. Furthermore, the data analysis time is brief, and only simple equipment is required. (C) 2014 Published by Elsevier Ltd.

Avaliação da dose de radiação absorvida em exames radiológicos durante o planejamento radioterápico

Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

NIL_004 Summary of session C6: Q&A-everything you wanted to know about gravitational waves but were afraid to ask

The paper summarizes the parallel session C6 Q&A-everything you wanted to know about gravitational waves but were afraid to ask of the joint 10th Amaldi Conference on Gravitational Waves and 20th International Conference on General Relativity and Gravitation.

Different outcomes of peritoneal catheter percutaneous placement by nephrologists using a trocar versus the Seldinger technique: the experience of two Brazilian centers

A good catheter implantation technique is important to allow effective peritoneal access function and long-term technique survival. Studies regarding results obtained by nephrologists in comparison with different techniques have been limited. The aim of this study was to investigate the rate of early catheter-related complications and catheter survival in two Brazilian centers, according to two different percutaneous methods of catheter implantation performed by nephrologist team. Adult incident patients recruited from January 2006 to July 2013 having undergone first peritoneal dialysis (PD) catheter implantation were included in the analysis. Mechanical and infectious early complication rates were defined as time to the first event occurring up to 3 months. Four hundred and forty-five consecutive Tenckhoff catheters were implanted by nephrologist team percutaneously after antibiotic prophylaxis in an operating room: trocar was used in 349 (78.4 %) and Seldinger technique (ST) in 99 (21.6 %). The ST was significantly associated with a lower rate of leak (16.3 vs 3 %, p = 0.03) and outflow failure due to tip catheter migration (22.6 vs 10.1 %, p = 0.04), while early infectious complication rates were similar between the two groups (p = 0.59). Long-term catheter survival was higher in Seldinger group (log-rank, p = 0.031). By Cox multivariate analysis, adjusted for age, sex, and diabetes, the ST remained independently associated with better catheter survival [HR 0.681 (0.462-0.910), p = 0.04]. As conclusion, our experience showed better PD outcomes with the ST than trocar method of catheter implantation by nephrologist.

Implementation of an F-statistic all-sky search for continuous gravitational waves in Virgo VSR1 data

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).

Missing transverse energy performance of the CMS detector

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Alignment of the CMS tracker with LHC and cosmic ray data

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Description and performance of track and primary-vertex reconstruction with the CMS tracker

A description is provided of the software algorithms developed for the CMS tracker both for reconstructing charged-particle trajectories in proton-proton interactions and for using the resulting tracks to estimate the positions of the LHC luminous region and individual primary-interaction vertices. Despite the very hostile environment at the LHC, the performance obtained with these algorithms is found to be excellent. For t (t) over bar events under typical 2011 pileup conditions, the average track-reconstruction efficiency for promptly-produced charged particles with transverse momenta of p(T) > 0.9GeV is 94% for pseudorapidities of vertical bar eta vertical bar < 0.9 and 85% for 0.9 < vertical bar eta vertical bar < 2.5. The inefficiency is caused mainly by hadrons that undergo nuclear interactions in the tracker material. For isolated muons, the corresponding efficiencies are essentially 100%. For isolated muons of p(T) = 100GeV emitted at vertical bar eta vertical bar < 1.4, the resolutions are approximately 2.8% in p(T), and respectively, 10 m m and 30 mu m in the transverse and longitudinal impact parameters. The position resolution achieved for reconstructed primary vertices that correspond to interesting pp collisions is 10-12 mu m in each of the three spatial dimensions. The tracking and vertexing software is fast and flexible, and easily adaptable to other functions, such as fast tracking for the trigger, or dedicated tracking for electrons that takes into account bremsstrahlung.

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%.

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.

Estudo da dose efetiva, razão sinal-ruído e razão contraste-ruído em tomografia computadorizada de múltiplos detetores

Since discovery, computed tomography is a widely used diagnostic modality. However, this modality imparts relatively high doses to the patients and with fast technological advancement, it is necessary optimize the doses used and ensure the quality of the images through a quality assurance program. This work intended to compare Computed Tomography Dose Index (CTDIW) and effective dose with components of image quality: the Contrast-to-Noise Ratio (CNR) and Signal-to-Noise Ratio (SNR), and a quality factor (Q) deduced by the Rose model for two groups of computed tomography units. The first group was composed by equipments with 10 up to 16 slices and the second one presented 40 up to 320 slices detectors, for the protocols of head and abdomen. It was realized a comparison between different selectable parameters in the protocol of a Philips Brilliance 16, too. The results of the first group to CTDIW, effective dose, SNR and CNR showed variations of 28%, 33%, 37% and 32% respectively for head protocol, and 21%, 27%, 43% and 37% respectively for abdomen protocol. The results of the group 2 to CTDIW, effective dose, SNR and CNR showed variations of 15%, 26%, 36% and 34% respectively for the head protocol, and 8%, 13%, 50% and 60% respectively for abdomen protocol. The comparison between both groups demonstrated similar levels of doses impartation to patients though having so many different configurations, if the uncertainties associated with this measurement were considered. The results of the comparison between different parameters in the Philips Brilliance 16 scanner were in agreement with expected