Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Comparison of the methane oxidation rate in four media

Landfill gas emissions are one of the main sources of anthropogenic methane (CH4), a major greenhouse gas. In this paper, an economically attractive alternative to minimize greenhouse gas emissions from municipal solid waste landfills was sought. This alternative consists in special biofilters as landfill covers with oxidative capacity in the presence of CH4. To improve the quality/cost ratio of the project, compost was chosen as one of the cover substrates and soil (Typic red yellow-silt-clay Podzolic) as the other. The performance of four substrates was studied in laboratory experiments: municipal solid waste (MSW) compost, soil, and two soil-compost at different proportions. This study aimed to evaluate the suitability and environmental compatibility as a means of CH4 oxidation in biofilters. Four biofilters were constructed in 60 cm PVC tubes with an internal diameter of 10 cm. Each filter contained 2.3 L of oxidizing substrate at the beginning of the experiment. The gas used was a mixture of CH4 and air introduced at the bottom of each biofilter, at a flow of 150 mL min-1, by a flow meter. One hundred days after the beginning of the experiment, the best biofilter was the MSW compost with an oxidation rate of 990 g m-3 day-1 , corresponding to an efficiency of 44 %. It can be concluded that the four substrates studied have satisfactory oxidative capacity, and the substrates can be used advantageously as cover substrate of MSW landfills

Effects of porosity, dry unit weight, cement content and void/cement ratio on unconfined compressive strength of roof tile waste-silty soil mixtures

One of the conventional ways to improve the mechanical behavior of soils is to mix them with cementing agents such as cement, lime and fly ash. Recently, introduction to alternative materials or sub-products that can be adopted to improve the soil strength is of paramount importance. Therefore, the present study aims to investigate the effects of porosity (η), dry unit weight (γd) of molding, cement content (C) and porosity/volumetric cement content ratio (η/Civ) or void/cement ratio on the unconfined compressive strength (qu or UCS) of silty soil–roof tile waste (RT) mixtures. Soil samples are molded into four different dry unit weights (i.e. 13 kN/m3, 13.67 kN/m3, 14.33 kN/m3 and 15 kN/m3) using 3%, 6% and 9% cement and 5%, 15% and 30% RT. The results show that with the addition of cement, the strength of the RT–soil mixtures increases in a linear manner. On the other hand, the addition of RT decreases qu of the samples at a constant percentage of cement, and the decrease in porosity can increase qu. A dosage equation is derived from the experimental data using the porosity/volumetric cement content ratio (η/Civ) where the control variables are the moisture content, crushed tile content, cement content and porosity. Keywords: Roof tile waste (RT), Voids/cement ratio, Reuse, Ground improvemen

G1P[8] species A rotavirus over 27years – Pre- and post-vaccination eras – in Brazil: Full genomic constellation analysis and no evidence for selection pressure by Rotarix® vaccine

AbstractEpidemiological data on species A rotavirus (RVA) infections have demonstrated the genetic diversity of strains circulating worldwide. Many G and P genotype combinations have been described over the years, varying regionally and temporally, especially in developing countries. However, the most common G and P genotype combinations identified in RVA human strains worldwide are G1P[8], G2P[4], G3P[8], G4P[8] and G9P[8]. RVA genotype G1P[8] strains are responsible for more than 50% of child infections worldwide and component of the two vaccines (Rotarix® [RV1] and RotaTeq® [RV5]) licensed globally. For a better understanding of the evolutionary mechanisms of this genotype in Brazil, phylogenetic analyses based on the 11 RVA genome segments (genomic constellation) from 90 G1P[8] RVA strains collected in two eras – (i) pre-vaccination with RV1 (1996–February 2006); (ii) post-vaccination (March 2006–2013) – in different Brazilian states were performed. The results showed the Wa-like genomic constellation of the Brazilian G1P[8] strains with a I1-R1-C1-M1-A1-N1-T1-E1-H1 specificity, except for two strains (rj14055-07 and ba19030-10) that belong to a I1-R1-C1-M1-A1-N1-T3-E1-H1 genomic constellation, evidencing the occurrence of reassortment (Wa-like×AU-1-like) of the NSP3 gene. Reassortment events were also demonstrated between Brazilian G1P[8] strains and the RV1 vaccine strain in some genes in vaccinated and unvaccinated children. VP7 and VP8* antigenic site analysis showed that the amino acid substitutions observed in samples collected after the introduction of RV1 in Brazil were already detected in samples collected in the 1980s and 1990s, suggesting that mass Brazilian RV1 vaccination had no impact on the diversity observed inside antigenic sites for these two proteins

Prevalence and genomic characterization of G2P[4] group A rotavirus strains during monovalent vaccine introduction in Brazil

This study aims to: estimate the prevalence of G2P[4] rotaviruses in Brazil between 2001-2011 from patients with acute gastroenteritis; perform phylogenetic analyses of G2P[4] Brazilian strains (from vaccinated and non-vaccinated children) based on VP7 and VP8(∗) encoding genes and analyze the antigenic regions of these proteins comparing with RV1; and assess the full genetic background of eleven selected Brazilian strains. The G2P[4] detection rate among RVA positive samples was 0/157 in 2001, 3/226 (1.3%) in 2002, 0/514 in 2003, 0/651 in 2004, 31/344 (9%)/2005, 112/227 (49%)/2006, 139/211 (66%)/2007, 240/284 (85%)/2008, 66/176 (37.5%)/2009, 367/422 (87%)/2010 and 75/149 (50%)/2011. For the VP7 and VP8(∗) encoding genes, 52 sequences were analyzed and shared up to 99% nucleotide identity with other contemporary G2P[4] strains detected worldwide, grouping into different clusters. Most differences inside antigenic epitopes of VP7 and VP8(∗) have been maintained in the G2P[4] Brazilian strains along the years, and all were present before RV1 introduction. Eleven G2P[4] strains (4-vaccinated/7-non-vaccinated) were completely characterized and possessed the typical DS-1-like genotype constellation (G2-P[4]-I2-R2-C2-M2-A2-N2-T2-E2-H2) sharing up to 99% of nucleotide identity with contemporary worldwide strains. Reassortments between Brazilian G2P[4] human strains were observed. In conclusion, the data obtained in the current study suggests that implementation of RV1 vaccination might not influence the genetic diversity observed in G2P[4] analyzed strains. Several factors might have contributed to the increased prevalence of this genotype in Brazil since 2005: the introduction of RV1 into the Brazilian National Immunization Program has resulted in a decrease in the relative prevalence of predominant Wa-like RVA strains facilitating the increase of the heterotypic (DS-1-like) RVA strain G2P[4] in the Brazilian population; the genetic diversity found in different geographical regions throughout the years before, and after the introduction of RV1; the long period of low or no circulation of this genotype in Brazil previous to RV1 introduction could have created favorable conditions for the accumulation of immunological susceptible individuals.publisher: Elsevier articletitle: Prevalence and genomic characterization of G2P[4] group A rotavirus strains during monovalent vaccine introduction in Brazil journaltitle: Infection, Genetics and Evolution articlelink: http://dx.doi.org/10.1016/j.meegid.2014.09.012 content_type: article copyright: Copyright © 2014 Elsevier B.V.status: publishe

Prevalence and genomic characterization of G2P[4] group A rotavirus strains during monovalent vaccine introduction in Brazil

Made available in DSpace on 2015-06-12T13:57:51Z (GMT). No. of bitstreams: 2 license.txt: 1914 bytes, checksum: 7d48279ffeed55da8dfe2f8e81f3b81f (MD5) tatiana_roseetal_IOC_2014.pdf: 862520 bytes, checksum: 3124bc7c8df41b90c55fc26589eb62cf (MD5) Previous issue date: 2014Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.University of Leuven. Rega Institute for Medical Research. Department of Microbiology and Immunology.Laboratory of Clinical and Epidemiological Virology. Leuven, Belgium.University of Leuven. Rega Institute for Medical Research. Department of Microbiology and Immunology.Laboratory of Clinical and Epidemiological Virology. Leuven, Belgium.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.This study aims to: estimate the prevalence of G2P[4] rotaviruses in Brazil between 2001–2011 from patients with acute gastroenteritis; perform phylogenetic analyses of G2P[4] Brazilian strains (from vaccinated and non-vaccinated children) based on VP7 and VP8⁄ encoding genes and analyze the antigenic regions of these proteins comparing with RV1; and assess the full genetic background of eleven selected Brazilian strains. The G2P[4] detection rate among RVA positive samples was 0/157 in 2001, 3/226 (1.3%) in 2002, 0/514 in 2003, 0/651 in 2004, 31/344 (9%)/2005, 112/227 (49%)/2006, 139/211 (66%)/2007, 240/ 284 (85%)/2008, 66/176 (37.5%)/2009, 367/422 (87%)/2010 and 75/149 (50%)/2011. For the VP7 and VP8⁄ encoding genes, 52 sequences were analyzed and shared up to 99% nucleotide identity with other contemporary G2P[4] strains detected worldwide, grouping into different clusters. Most differences inside antigenic epitopes of VP7 and VP8⁄ have been maintained in the G2P[4] Brazilian strains along the years, and all were present before RV1 introduction. Eleven G2P[4] strains (4-vaccinated/7-non-vaccinated) were completely characterized and possessed the typical DS-1-like genotype constellation (G2-P[4]-I2- R2-C2-M2-A2-N2-T2-E2-H2) sharing up to 99% of nucleotide identity with contemporary worldwide strains. Reassortments between Brazilian G2P[4] human strains were observed. In conclusion, the data obtained in the current study suggests that implementation of RV1 vaccination might not influence the genetic diversity observed in G2P[4] analyzed strains. Several factors might have contributed to the increased prevalence of this genotype in Brazil since 2005: the introduction of RV1 into the Brazilian National Immunization Program has resulted in a decrease in the relative prevalence of predominant Wa-like RVA strains facilitating the increase of the heterotypic (DS-1-like) RVA strain G2P[4] in the Brazilian population; the genetic diversity found in different geographical regions throughout the years before, and after the introduction of RV1; the long period of low or no circulation of this genotype in Brazil previous to RV1 introduction could have created favorable conditions for the accumulation of immunological susceptible individuals