62 research outputs found

    Detecting z > 2 Type IIn Supernovae

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    Type IIn supernovae (SNe IIn) dominate the brightest supernova events in observed FUV flux (~1200-2000A). We show that multi-band, multi-epoch optical surveys complete to m_r = 27 can detect the FUV emission of ~25 z > 2 SNe IIn deg^-2 yr^-1 rest-frame (~10 SNe IIn deg^-2 yr^-1 observed-frame) to 4 sigma using a technique monitoring color-selected galaxies. Moreover, the strength and evolution of the bright emission lines observed in low redshift SNe IIn imply that the Ly-a emission features in ~70% of z > 2 SNe IIn are above 8m-class telescope spectroscopic thresholds for ~2 yr rest-frame. As a result, existing facilities have the capability to both photometrically detect and spectroscopically confirm z > 2 SNe IIn and pave the way for efficient searches by future 8m-class survey and 30m-class telescopes. The method presented here uses the sensitivities and wide-field capabilities of current optical instruments and exploits (1) the efficiency of z > 2 galaxy color-selection techniques, (2) the intrinsic brightness distribution ( = -19.0 +/-0.9) and blue profile of SNe IIn continua, (3) the presence of extremely bright, long-lived emission features, and (4) the potential to detect blueshifted SNe Ly-a emission shortward of host galaxy Ly-a features.Comment: 26 pages (pre-print), 6 figures, accepted Ap

    An Ejectable Data Recorder Subsystem for the Ascent Abort-2 Test Flight of the Orion Launch Abort System

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    The Ejectable Data Record (EDR) subsystem was a unique development opportunity at NASA with challenges that necessitated innovation. EDR employed a skunkworks development approach in which we designed, built, and delivered 47 end items, not including ground support equipment. We used as many COTS components as possible, we looked for process efficiencies to meet our tight deadlines, and the EDR team was involved in the flight operations of the AA-2 test flight and responsible for the recovery operations of the ejected payloads. This paper will discuss the design and development of the EDR subsystem, as well as the results of the system performance during the AA-2 test flight

    Correction to: Cluster identification, selection, and description in Cluster randomized crossover trials: the PREP-IT trials

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    An amendment to this paper has been published and can be accessed via the original article

    Patient and stakeholder engagement learnings: PREP-IT as a case study

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    Modelling human choices: MADeM and decision‑making

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    Research supported by FAPESP 2015/50122-0 and DFG-GRTK 1740/2. RP and AR are also part of the Research, Innovation and Dissemination Center for Neuromathematics FAPESP grant (2013/07699-0). RP is supported by a FAPESP scholarship (2013/25667-8). ACR is partially supported by a CNPq fellowship (grant 306251/2014-0)

    A systematic review and meta-analysis of the influence of peritoneal dialysis catheter type on complication rate and catheter survival

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    Peritoneal dialysis (PD) is an effective treatment for end-stage renal disease. There are several configurations of PD catheter design that may impact catheter function, such as the shape of the intraperitoneal segment, the number of cuffs, and the subcutaneous configuration. This review and meta-analysis was carried out to determine whether there is a clinical advantage for one of the catheter types or configurations. Comprehensive searches were conducted in MEDLINE, Embase, and CENTRAL (the Cochrane Library 2012, issue 10). The methodology was in accordance with the Cochrane Handbook for Interventional Systematic Reviews and written based on the PRISMA statement. The initial search yielded 682 hits from which 13 randomized controlled trials were identified. Outcomes of interest were as follows: catheter survival, drainage dysfunction, migration, leakage, exit-site infections, peritonitis, and catheter removal. Comparing straight vs. swan neck and single vs. double-cuffed catheters, no differences were found when results were pooled. Comparison of straight vs. coiled-tip catheters demonstrated that survival was significantly different in favor of straight catheters (hazard ratio 2.05; confidence interval 1.10-3.79, P = 0.02). For surgically inserted catheters, the removal rate and survival at 1 year after insertion were significantly in favor of straight catheters. Our meta-analysis clearly demonstrates benefits for catheters with a straight intraperitoneal segment
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