7,469 research outputs found
Parallelized Inference for Gravitational-Wave Astronomy
Bayesian inference is the workhorse of gravitational-wave astronomy, for
example, determining the mass and spins of merging black holes, revealing the
neutron star equation of state, and unveiling the population properties of
compact binaries. The science enabled by these inferences comes with a
computational cost that can limit the questions we are able to answer. This
cost is expected to grow. As detectors improve, the detection rate will go up,
allowing less time to analyze each event. Improvement in low-frequency
sensitivity will yield longer signals, increasing the number of computations
per event. The growing number of entries in the transient catalog will drive up
the cost of population studies. While Bayesian inference calculations are not
entirely parallelizable, key components are embarrassingly parallel:
calculating the gravitational waveform and evaluating the likelihood function.
Graphical processor units (GPUs) are adept at such parallel calculations. We
report on progress porting gravitational-wave inference calculations to GPUs.
Using a single code - which takes advantage of GPU architecture if it is
available - we compare computation times using modern GPUs (NVIDIA P100) and
CPUs (Intel Gold 6140). We demonstrate speed-ups of for
compact binary coalescence gravitational waveform generation and likelihood
evaluation and more than for population inference within the
lifetime of current detectors. Further improvement is likely with continued
development. Our python-based code is publicly available and can be used
without familiarity with the parallel computing platform, CUDA.Comment: 5 pages, 4 figures, submitted to PRD, code can be found at
https://github.com/ColmTalbot/gwpopulation
https://github.com/ColmTalbot/GPUCBC
https://github.com/ADACS-Australia/ADACS-SS18A-RSmith Add demonstration of
improvement in BNS spi
Recommended from our members
The Jet-Driven Outflow In The Radio Galaxy SDSS J1517+3353: Implications For Double-Peaked Narrow-Line Active Galactic Nucleus
We report on the study of an intriguing active galaxy that was selected as a potential multiple supermassive black hole merger in the early-type host SDSS J151709.20+335324.7 (z = 0.135) from a complete search for double-peaked [O III] lines from the SDSS spectroscopic quasi-stellar object (QSO) database. Ground-based SDSS imaging reveals two blue structures on either side of the photometric center of the host galaxy, separated from each other by about 5.7 kpc. From a combination of SDSS fiber and Keck/HIRES long-slit spectroscopy, it is demonstrated that, in addition to these two features, a third distinct structure surrounds the nucleus of the host galaxy. All three structures exhibit highly ionized line emission with line ratios characteristic of Seyfert II active galactic nuclei. The analysis of spatially resolved emission-line profiles from the HIRES spectrum reveal three distinct kinematic subcomponents, one at rest and the other two moving at -350 km s(-1) and 500 km s(-1) with respect to the systemic velocity of the host galaxy. A comparison of imaging and spectral data confirm a strong association between the kinematic components and the spatial knots, which implies a highly disturbed and complex active region in this object. A comparative analysis of the broadband positions, colors, kinematics, and spectral properties of the knots in this system lead to two plausible explanations: (1) a multiple active galactic nucleus (AGN) produced due to a massive dry merger, or (2) a very powerful radio jet-driven outflow. Subsequent VLA radio imaging reveals a clear jet aligned with the emission-line gas, confirming the latter explanation. We use the broadband radio measurements to examine the impact of the jet on the interstellar medium of the host galaxy, and find that the energy in the radio lobes can heat a significant fraction of the gas to the virial temperature. Finally, we discuss tests that may help future surveys distinguish between jet-driven kinematics and true black-hole binaries. J1517+3353 is a remarkable laboratory for AGN feedback and warrants deeper follow-up study. In the Appendix, we present high-resolution radio imaging of a second AGN with double-peaked [O III] lines, SDSS J112939.78+605742.6, which shows a sub-arcsecond radio jet. If the double-peaked nature of the narrow lines in radio-loud AGNs are generally due to radio jet interactions, we suggest that extended radio structure should be expected in most of such systems.NSF AST-0507483, AST-0808133University of Texas at AustinAlfred P. Sloan FoundationParticipating InstitutionsNational Aeronautics and Space AdministrationU.S. Department of EnergyJapanese MonbukagakushoMax Planck SocietyAstronom
Pilot Study: Implementing a Brief DBT Skills Program in Schools to Reduce Health Risk Behaviors Among Early Adolescents
A significant proportion of youth engage in health risk behaviors, which are of concern, as they are associated with adverse health consequences across development. Two factors associated with engagement in such behaviors are emotion dysregulation and impulsivity. Dialectical behavioral therapy (DBT) is an effective intervention that enhances emotion regulation skills to reduce problem behaviors among adolescent populations; however, limited research has been conducted implementing the program within school settings. The current study was a 9-week DBT skills group conducted among 80 middle school youth, with pre–posttest data among 53 students. Findings indicated feasibility to implement the program in schools and preliminary evidence of efficacy in decreasing youth’s likelihood to engage in risky, particularly among youth high on an emotion-based impulsivity trait. Brief DBT skills group may be an effective program to be utilized by school nurses and health-care teams to reduce health risk behaviors among school-aged youth
US Ireland Partnership Program: BEACONS: Biosafety for Environmental Contaminants Using Novel Sensors
BEACONS is a unique collaboration between the United States, Northern Ireland and the Republic of Ireland, that aims to develop a novel sample preparation device coupled to a portable sensor which will be capable of rapidly analyzing for the presence of major aquatic toxins and associated organisms in water samples. It harnesses the substantial complementary expertise of the international partners and their institutions to address a problem that has world-wide implications for human health and aquatic related industries. The results will be used for the generation of a commercially applicable prototype device that could have the potential to be applied to a wide range of different analytical problems. The program will involve significant exchange of personnel and expertise and will generate novel scientific data and approaches linked with the solution of a key problem for all the partners\u27 jurisdictions. This project will develop a set of easily portable instruments that can be utilized for biotoxin and toxic organism detection, and be adapted subsequently for monitoring of other potentially harmful organisms and their toxins. A key element for any field deployable sensing instrument is the acquisition and preparation of samples. Thus, the proposed research includes development of a sample preparation platform and associated protocols for concentration and delivery of targeted toxin and nucleic acid sequences to a hand-held detection device. The expected outcome is the development of a sample preparation module and assay methods for an optical detection device, based on planar waveguide technology, capable of measuring in real time the presence of both toxin producing organisms and the toxins themselves in coastal and fresh water samples. The sample preparation module will involve the integration of novel microfluidics with peptide nucleic acids (PNAs) and engineered broad affinity, highly stable capture antibodies. Resultant extracts will be introduced into the detection system, which will employ an array-based, planar waveguide technology previously incorporated into a hand-held device by a commercial partner and made available to project collaborators for development of assays for toxins and organisms. They will utilize highly specific, engineered antibodies for capturing toxin molecules and PNAs as capture probes to detect the corresponding toxigenic organisms. This technology is expected to provide new and improved means of assessing the potential risks associated with contamination of coastal and fresh water fishery resources by algal biotoxins. The US-Ireland Partnership Program has been endorsed at the highest political levels by the three jurisdictions (U.S., Republic of Ireland, and Northern Ireland). The added value for the U.S. from the BEACONS proposal includes a combination of significant intellectual and financial contributions from Ireland. Moreover, the project will involve a well coordinated exchange of researchers between the participating organizations. In particular, the opportunities of exchange visits for young scientists employed on the project will be important from both scientific and cultural perspectives. A critical element of detecting any analyte is sample processing. Therefore, in addition to stronger international collaborations and training of young scientists, this project aims to provide a new portable and flexible platform that can be adapted for the sensor-based detection of other biotoxins and/or microbes
Developing an Academic Library Assessment Plan: A Case Study
Purpose
– The purpose of this paper is to analyze the process of developing an academic library assessment plan and its relation to the furtherance of a culture of assessment.
Design/methodology/approach
– Qualitative study of a university library’s assessment planning process; findings based on documentary evidence as well as an employee survey; analysis framed in relationship to relevant literature.
Findings
– Planning for the future of assessment offered the Jerry Falwell Library a significant opportunity for organizational change. Evaluations of the planning process were mixed, but generally revealed evidence of conditions associated with the development of a culture of assessment. Participants saw planning as the product of both external and internal factors. The plan’s orientation toward value and impact, though clearly understood, was not universally appreciated. Implementation of the plan remains a substantial challenge.
Research limitations/implications
– Reliability is subject to the limitations inherent to qualitative methods. Single case study design limits generalizability to different contexts.
Practical implications
– The goal of developing a culture of assessment is not to be achieved easily or quickly. Library employees may be most inclined to support an assessment agenda when it is driven by internal factors such as quality improvement and the pursuit of efficiency and effectiveness.
Originality/value
– The study emphasizes the process of developing an assessment plan at a university with a strong teaching mission. Additionally, it provides insight into the relationship between assessment planning and a culture of assessment
Mitoxantrone is superior to doxorubicin in a multiagent weekly regimen for patients older than 60 with high-grade lymphoma: results of a BNLI randomized trial of PAdriaCEBO versus PMitCEBO
A prospective, multicenter, randomized trial was undertaken to compare the efficacy and toxicity of adriamycin with mitoxantrone within a 6-drug combination chemotherapy regimen for elderly patients (older than 60 years) with high-grade non-Hodgkin lymphoma (HGL) given for a minimum of 8 weeks. A total of 516 previously untreated patients aged older than 60 years were randomized to receive 1 of 2 anthracycline-containing regimens: adriamycin, 35 mg/m2 intravenously (IV) on day 1 (n = 259), or mitoxantrone, 7 mg/m2 IV on day 1 (n = 257); with prednisolone, 50 mg orally on days 1 to 14; cyclophosphamide, 300 mg/m2 IV on day 1; etoposide, 150 mg/m2 IV on day 1; vincristine, 1.4 mg/m2 IV on day 8; and bleomycin, 10 mg/m2 IV on day 8. Each 2-week cycle was administered for a minimum of 8 weeks in the absence of progression. Forty-three patients were ineligible for analysis. The overall and complete remission rates were 78% and 60% for patients receiving PMitCEBO and 69% and 52% for patients receiving PAdriaCEBO (P = .05, P = .12, respectively). Overall survival was significantly better with PMitCEBO than PAdriaCEBO (P = .0067). However, relapse-free survival was not significantly different (P = .16). At 4 years, 28% of PAdriaCEBO patients and 50% of PMitCEBO patients were alive (P = .0001). Ann Arbor stage III/IV, World Health Organization performance status 2-4, and elevated lactate dehydrogenase negatively influenced overall survival from diagnosis. In conclusion, the PMitCEBO 8-week combination chemotherapy regimen offers high response rates, durable remissions, and acceptable toxicity in elderly patients with HGL
Associations between diurnal preference, sleep quality and externalizing behaviours: a behavioural genetic analysis
Background - Certain aspects of sleep co-occur with externalizing behaviours in youth, yet little is known about these associations in adults. The present study: (1) examines the associations between diurnal preference (morningness versus eveningness), sleep quality and externalizing behaviours; (2) explores the extent to which genetic and environmental influences are shared between or are unique to these phenotypes; (3) examines the extent to which genetic and environmental influences account for these associations.
Method - Questionnaires assessing diurnal preference, sleep quality and externalizing behaviours were completed by 1556 young adult twins and siblings.
Results - A preference for eveningness and poor sleep quality were associated with greater externalizing symptoms [r=0.28 (95% CI 0.23–0.33) and 0.34 (95% CI 0.28–0.39), respectively]. A total of 18% of the genetic influences on externalizing behaviours were shared with diurnal preference and sleep quality and an additional 14% were shared with sleep quality alone. Non-shared environmental influences common to the phenotypes were small (2%). The association between diurnal preference and externalizing behaviours was mostly explained by genetic influences [additive genetic influence (A)=80% (95% CI 0.56–1.01)], as was the association between sleep quality and externalizing behaviours [A=81% (95% CI 0.62–0.99)]. Non-shared environmental (E) influences accounted for the remaining variance for both associations [E=20% (95% CI −0.01 to 0.44) and 19% (95% CI 0.01–0.38), respectively].
Conclusions - A preference for eveningness and poor sleep quality are moderately associated with externalizing behaviours in young adults. There is a moderate amount of shared genetic influences between the phenotypes and genetic influences account for a large proportion of the association between sleep and externalizing behaviours. Further research could focus on identifying specific genetic polymorphisms common to both sleep and externalizing behaviours
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