58 results
D.4 Safety and efficacy of delandistrogene moxeparvovec versus placebo in Duchenne muscular dystrophy (EMBARK): Pivotal Phase 3 primary results
- JR Mendell, F Muntoni, CM McDonald, EM Mercuri, E Ciafaloni, H Komaki, C Leon-Astudillo, A Nascimento, C Proud, U Schara-Schmidt, A Veerapandiyan, CM Zaidman, M Guridi, AP Murphy, C Reid, C Wandel, E Darton, S Mason, RA Potter, T Singh, W Zhang, P Fontoura, JS Elkins, LR Rodino-Klapac
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- Journal:
- Canadian Journal of Neurological Sciences / Volume 51 / Issue s1 / June 2024
- Published online by Cambridge University Press:
- 24 May 2024, pp. S9-S10
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Background: Duchenne muscular dystrophy (DMD) is caused by DMD gene mutations. Delandistrogene moxeparvovec is an investigational gene transfer therapy, developed to address the underlying cause of DMD. We report findings from Part 1 (52 weeks) of the two-part EMBARK trial (NCT05096221). Methods: Key inclusion criteria: Ambulatory patients aged ≥4-<8 years with a confirmed DMD mutation within exons 18–79 (inclusive); North Star Ambulatory Assessment (NSAA) score >16 and <29 at screening. Eligible patients were randomized 1:1 to intravenous delandistrogene moxeparvovec (1.33×1014 vg/kg) or placebo. The primary endpoint was change from baseline in NSAA total score to Week 52. Results: At Week 52 (n=125), the primary endpoint did not reach statistical significance, although there was a nominal difference in change from baseline in NSAA total score in the delandistrogene moxeparvovec (2.6, n=63) versus placebo groups (1.9, n=61). Key secondary endpoints (time to rise, micro-dystrophin expression, 10-meter walk/run) demonstrated treatment benefit in both age groups (4-5 and 6-7 years; p<0.05).There were no new safety signals, reinforcing the favorable and manageable safety profile observed to date. Conclusions: Based on the totality of functional assessments including the timed function tests, treatment with delandistrogene moxeparvovec indicates beneficial modification of disease trajectory.
MWA rapid follow-up of gravitational wave transients: Prospects for detecting prompt radio counterparts
- J. Tian, G. E. Anderson, A. J. Cooper, K. Gourdji, M. Sokolowski, A. Rowlinson, A. Williams, G. Sleap, D. Dobie, D. L. Kaplan, Tara Murphy, S. J. Tingay, F. H. Panther, P. D. Lasky, A. Bahramian, J. C. A. Miller-Jones, C. W. James, B. W. Meyers, S. J. McSweeney, P. J. Hancock
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 40 / 2023
- Published online by Cambridge University Press:
- 26 October 2023, e050
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We present and evaluate the prospects for detecting coherent radio counterparts to gravitational wave (GW) events using Murchison Widefield Array (MWA) triggered observations. The MWA rapid-response system, combined with its buffering mode ($\sim$4 min negative latency), enables us to catch any radio signals produced from seconds prior to hours after a binary neutron star (BNS) merger. The large field of view of the MWA ($\sim$$1\,000\,\textrm{deg}^2$ at 120 MHz) and its location under the high sensitivity sky region of the LIGO-Virgo-KAGRA (LVK) detector network, forecast a high chance of being on-target for a GW event. We consider three observing configurations for the MWA to follow up GW BNS merger events, including a single dipole per tile, the full array, and four sub-arrays. We then perform a population synthesis of BNS systems to predict the radio detectable fraction of GW events using these configurations. We find that the configuration with four sub-arrays is the best compromise between sky coverage and sensitivity as it is capable of placing meaningful constraints on the radio emission from 12.6% of GW BNS detections. Based on the timescales of four BNS merger coherent radio emission models, we propose an observing strategy that involves triggering the buffering mode to target coherent signals emitted prior to, during or shortly following the merger, which is then followed by continued recording for up to three hours to target later time post-merger emission. We expect MWA to trigger on $\sim$$5-22$ BNS merger events during the LVK O4 observing run, which could potentially result in two detections of predicted coherent emission.
Evaluation of an online research best practices training for community health workers and promotoras
- Susan L. Murphy, Gina M. Jay, Elias M. Samuels, Brenda L. Eakin, Alexandra E. Harper, Gretchen A. Piatt, Vanessa I. Trujillo, Kristen L. Weeks-Norton, Catherine W. Striley, Catina O’Leary, Jordan Hahn, Daphne C. Watkins, Linda B. Cottler, Sergio Aguilar Gaxiola
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- Journal:
- Journal of Clinical and Translational Science / Volume 7 / Issue 1 / 2023
- Published online by Cambridge University Press:
- 05 September 2023, e195
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Introduction:
Community health workers and promotoras (CHW/Ps) have a fundamental role in facilitating research with communities. However, no national standard training exists as part of the CHW/P job role. We developed and evaluated a culturally- and linguistically tailored online research best practices course for CHW/Ps to meet this gap.
Methods:After the research best practices course was developed, we advertised the opportunity to CHW/Ps nationwide to complete the training online in English or Spanish. Following course completion, CHW/Ps received an online survey to rate their skills in community-engaged research and their perceptions of the course using Likert scales of agreement. A qualitative content analysis was conducted on open-ended response data.
Results:104 CHW/Ps completed the English or Spanish course (n = 52 for each language; mean age 42 years SD ± 12); 88% of individuals identified as female and 56% identified as Hispanic, Latino, or Spaniard. 96%–100% of respondents reported improvement in various skills. Nearly all CHW/Ps (97%) agreed the course was relevant to their work, and 96% felt the training was useful. Qualitative themes related to working more effectively as a result of training included enhanced skills, increased resources, and building bridges between communities and researchers.
Discussion:The CHW/P research best practices course was rated as useful and relevant by CHW/Ps, particularly for communicating about research with community members. This course can be a professional development resource for CHW/Ps and could serve as the foundation for a national standardized training on their role related to research best practices.
Entrainment in 3D hydrodynamics simulations of neon burning
- F. Rizzuti, R. Hirschi, C. Georgy, W. D. Arnett, C. Meakin, A. StJ. Murphy
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- Journal:
- Proceedings of the International Astronomical Union / Volume 18 / Issue S361 / May 2022
- Published online by Cambridge University Press:
- 29 August 2024, pp. 353-358
- Print publication:
- May 2022
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Our knowledge of massive star evolution is limited by uncertainties linked with multi-dimensional processes taking place in stellar interiors. Important examples are convective boundary mixing (CBM) and entrainment, which are implemented in 1D stellar evolution models assuming simplified prescriptions. 3D hydrodynamics models can improve these prescriptions by studying realistic multi-D processes for a short timerange (minutes or hours). In these proceedings, we present results coming from a new set of high-resolution hydrodynamics simulations of a neon-burning shell in a massive star, and discuss how the entrainment law can be calibrated from 3D models and then used to improve 1D stellar evolution prescriptions.
Early-time searches for coherent radio emission from short GRBs with the Murchison Widefield Array
- J. Tian, G. E. Anderson, P. J. Hancock, J. C. A. Miller-Jones, M. Sokolowski, A. Rowlinson, A. Williams, J. Morgan, N. Hurley-Walker, D. L. Kaplan, Tara Murphy, S. J. Tingay, M. Johnston-Hollitt, K. W. Bannister, M. E. Bell, B. W. Meyers
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 39 / 2022
- Published online by Cambridge University Press:
- 03 February 2022, e003
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Many short gamma-ray bursts (GRBs) originate from binary neutron star mergers, and there are several theories that predict the production of coherent, prompt radio signals either prior, during, or shortly following the merger, as well as persistent pulsar-like emission from the spin-down of a magnetar remnant. Here we present a low frequency (170–200 MHz) search for coherent radio emission associated with nine short GRBs detected by the Swift and/or Fermi satellites using the Murchison Widefield Array (MWA) rapid-response observing mode. The MWA began observing these events within 30–60 s of their high-energy detection, enabling us to capture any dispersion delayed signals emitted by short GRBs for a typical range of redshifts. We conducted transient searches at the GRB positions on timescales of 5 s, 30 s, and 2 min, resulting in the most constraining flux density limits on any associated transient of 0.42, 0.29, and 0.084 Jy, respectively. We also searched for dispersed signals at a temporal and spectral resolution of 0.5 s and 1.28 MHz, but none were detected. However, the fluence limit of 80–100 Jy ms derived for GRB 190627A is the most stringent to date for a short GRB. Assuming the formation of a stable magnetar for this GRB, we compared the fluence and persistent emission limits to short GRB coherent emission models, placing constraints on key parameters including the radio emission efficiency of the nearly merged neutron stars ( $\epsilon_r\lesssim10^{-4}$ ), the fraction of magnetic energy in the GRB jet ( $\epsilon_B\lesssim2\times10^{-4}$ ), and the radio emission efficiency of the magnetar remnant ( $\epsilon_r\lesssim10^{-3}$ ). Comparing the limits derived for our full GRB sample (along with those in the literature) to the same emission models, we demonstrate that our fluence limits only place weak constraints on the prompt emission predicted from the interaction between the relativistic GRB jet and the interstellar medium for a subset of magnetar parameters. However, the 30-min flux density limits were sensitive enough to theoretically detect the persistent radio emission from magnetar remnants up to a redshift of $z\sim0.6$ . Our non-detection of this emission could imply that some GRBs in the sample were not genuinely short or did not result from a binary neutron star merger, the GRBs were at high redshifts, these mergers formed atypical magnetars, the radiation beams of the magnetar remnants were pointing away from Earth, or the majority did not form magnetars but rather collapse directly into black holes.
The ASKAP Variables and Slow Transients (VAST) Pilot Survey
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- Tara Murphy, David L. Kaplan, Adam J. Stewart, Andrew O’Brien, Emil Lenc, Sergio Pintaldi, Joshua Pritchard, Dougal Dobie, Archibald Fox, James K. Leung, Tao An, Martin E. Bell, Jess W. Broderick, Shami Chatterjee, Shi Dai, Daniele d’Antonio, Gerry Doyle, B. M. Gaensler, George Heald, Assaf Horesh, Megan L. Jones, David McConnell, Vanessa A. Moss, Wasim Raja, Gavin Ramsay, Stuart Ryder, Elaine M. Sadler, Gregory R. Sivakoff, Yuanming Wang, Ziteng Wang, Michael S. Wheatland, Matthew Whiting, James R. Allison, C. S. Anderson, Lewis Ball, K. Bannister, D. C.-J. Bock, R. Bolton, J. D. Bunton, R. Chekkala, A. P Chippendale, F. R. Cooray, N. Gupta, D. B. Hayman, K. Jeganathan, B. Koribalski, K. Lee-Waddell, Elizabeth K. Mahony, J. Marvil, N. M. McClure-Griffiths, P. Mirtschin, A. Ng, S. Pearce, C. Phillips, M. A. Voronkov
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 38 / 2021
- Published online by Cambridge University Press:
- 12 October 2021, e054
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The Variables and Slow Transients Survey (VAST) on the Australian Square Kilometre Array Pathfinder (ASKAP) is designed to detect highly variable and transient radio sources on timescales from 5 s to $\sim\!5$ yr. In this paper, we present the survey description, observation strategy and initial results from the VAST Phase I Pilot Survey. This pilot survey consists of $\sim\!162$ h of observations conducted at a central frequency of 888 MHz between 2019 August and 2020 August, with a typical rms sensitivity of $0.24\ \mathrm{mJy\ beam}^{-1}$ and angular resolution of $12-20$ arcseconds. There are 113 fields, each of which was observed for 12 min integration time, with between 5 and 13 repeats, with cadences between 1 day and 8 months. The total area of the pilot survey footprint is 5 131 square degrees, covering six distinct regions of the sky. An initial search of two of these regions, totalling 1 646 square degrees, revealed 28 highly variable and/or transient sources. Seven of these are known pulsars, including the millisecond pulsar J2039–5617. Another seven are stars, four of which have no previously reported radio detection (SCR J0533–4257, LEHPM 2-783, UCAC3 89–412162 and 2MASS J22414436–6119311). Of the remaining 14 sources, two are active galactic nuclei, six are associated with galaxies and the other six have no multi-wavelength counterparts and are yet to be identified.
Murchison Widefield Array rapid-response observations of the short GRB 180805A
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- G. E. Anderson, P. J. Hancock, A. Rowlinson, M. Sokolowski, A. Williams, J. Tian, J. C. A. Miller-Jones, N. Hurley-Walker, K. W. Bannister, M. E. Bell, C. W. James, D. L. Kaplan, Tara Murphy, S. J. Tingay, B. W. Meyers, M. Johnston-Hollitt, R. B. Wayth
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 38 / 2021
- Published online by Cambridge University Press:
- 10 June 2021, e026
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Here we present stringent low-frequency (185 MHz) limits on coherent radio emission associated with a short-duration gamma-ray burst (SGRB). Our observations of the short gamma-ray burst (GRB) 180805A were taken with the upgraded Murchison Widefield Array (MWA) rapid-response system, which triggered within 20s of receiving the transient alert from the Swift Burst Alert Telescope, corresponding to 83.7 s post-burst. The SGRB was observed for a total of 30 min, resulting in a $3\sigma$ persistent flux density upper limit of 40.2 mJy beam–1. Transient searches were conducted at the Swift position of this GRB on 0.5 s, 5 s, 30 s and 2 min timescales, resulting in $3\sigma$ limits of 570–1 830, 270–630, 200–420, and 100–200 mJy beam–1, respectively. We also performed a dedispersion search for prompt signals at the position of the SGRB with a temporal and spectral resolution of 0.5 s and 1.28 MHz, respectively, resulting in a $6\sigma$ fluence upper-limit range from 570 Jy ms at DM $=3\,000$ pc cm–3 ( $z\sim 2.5$ ) to 1 750 Jy ms at DM $=200$ pc cm–3 ( $z\sim 0.1)$ , corresponding to the known redshift range of SGRBs. We compare the fluence prompt emission limit and the persistent upper limit to SGRB coherent emission models assuming the merger resulted in a stable magnetar remnant. Our observations were not sensitive enough to detect prompt emission associated with the alignment of magnetic fields of a binary neutron star just prior to the merger, from the interaction between the relativistic jet and the interstellar medium (ISM) or persistent pulsar-like emission from the spin-down of the magnetar. However, in the case of a more powerful SGRB (a gamma-ray fluence an order of magnitude higher than GRB 180805A and/or a brighter X-ray counterpart), our MWA observations may be sensitive enough to detect coherent radio emission from the jet-ISM interaction and/or the magnetar remnant. Finally, we demonstrate that of all current low- frequency radio telescopes, only the MWA has the sensitivity and response times capable of probing prompt emission models associated with the initial SGRB merger event.
The Rapid ASKAP Continuum Survey I: Design and first results
- Part of
- D. McConnell, C. L. Hale, E. Lenc, J. K. Banfield, George Heald, A. W. Hotan, James K. Leung, Vanessa A. Moss, Tara Murphy, Andrew O’Brien, Joshua Pritchard, Wasim Raja, Elaine M. Sadler, Adam Stewart, Alec J. M. Thomson, M. Whiting, James R. Allison, S. W. Amy, C. Anderson, Lewis Ball, Keith W. Bannister, Martin Bell, Douglas C.-J. Bock, Russ Bolton, J. D. Bunton, A. P. Chippendale, J. D. Collier, F. R. Cooray, T. J. Cornwell, P. J. Diamond, P. G. Edwards, N. Gupta, Douglas B. Hayman, Ian Heywood, C. A. Jackson, Bärbel S. Koribalski, Karen Lee-Waddell, N. M. McClure-Griffiths, Alan Ng, Ray P. Norris, Chris Phillips, John E. Reynolds, Daniel N. Roxby, Antony E. T. Schinckel, Matt Shields, Chenoa Tremblay, A. Tzioumis, M. A. Voronkov, Tobias Westmeier
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- Publications of the Astronomical Society of Australia / Volume 37 / 2020
- Published online by Cambridge University Press:
- 30 November 2020, e048
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The Rapid ASKAP Continuum Survey (RACS) is the first large-area survey to be conducted with the full 36-antenna Australian Square Kilometre Array Pathfinder (ASKAP) telescope. RACS will provide a shallow model of the ASKAP sky that will aid the calibration of future deep ASKAP surveys. RACS will cover the whole sky visible from the ASKAP site in Western Australia and will cover the full ASKAP band of 700–1800 MHz. The RACS images are generally deeper than the existing NRAO VLA Sky Survey and Sydney University Molonglo Sky Survey radio surveys and have better spatial resolution. All RACS survey products will be public, including radio images (with $\sim$ 15 arcsec resolution) and catalogues of about three million source components with spectral index and polarisation information. In this paper, we present a description of the RACS survey and the first data release of 903 images covering the sky south of declination $+41^\circ$ made over a 288-MHz band centred at 887.5 MHz.
Effects of zinc source and dietary concentration on serum zinc concentrations, growth performance, wool and reproductive characteristics in developing rams
- C. M. Page, M. L. Van Emon, T. W. Murphy, C. K. Larson, J. G. Berardinelli, I. R. McGregor, J. B. Taylor, W. C. Stewart
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Dietary Zn has significant impacts on the growth and development of breeding rams. The objectives of this study were to evaluate the effects of dietary Zn source and concentration on serum Zn concentration, growth performance, wool traits and reproductive performance in rams. Forty-four Targhee rams (14 months; 68 ± 18 kg BW) were used in an 84-day completely randomized design and were fed one of three pelleted dietary treatments: (1) a control without fortified Zn (CON; n = 15; ~1 × NRC); (2) a diet fortified with a Zn amino acid complex (ZnAA; n = 14; ~2 × NRC) and (3) a diet fortified with ZnSO4 (ZnSO4; n = 15; ~2 × NRC). Growth and wool characteristics measured throughout the course of the study were BW, average daily gain (ADG), dry matter intake (DMI), feed efficiency (G : F), longissimus dorsi muscle depth (LMD), back fat (BF), wool staple length (SL) and average fibre diameter (AFD). Blood was collected from each ram at four time periods to quantify serum Zn and testosterone concentrations. Semen was collected 1 to 2 days after the trial was completed. There were no differences in BW (P = 0.45), DMI (P = 0.18), LMD (P = 0.48), BF (P = 0.47) and AFD (P = 0.9) among treatment groups. ZnSO4 had greater (P ≤ 0.03) serum Zn concentrations compared with ZnAA and CON treatments. Rams consuming ZnAA had greater (P ≤ 0.03) ADG than ZnSO4 and CON. There tended to be differences among groups for G : F (P = 0.06), with ZnAA being numerically greater than ZnSO4 and CON. Wool staple length regrowth was greater (P < 0.001) in ZnSO4 and tended to be longer (P = 0.06) in ZnAA treatment group compared with CON. No differences were observed among treatments in scrotal circumference, testosterone, spermatozoa concentration within ram semen, % motility, % live sperm and % sperm abnormalities (P ≥ 0.23). Results indicated beneficial effects of feeding increased Zn concentrations to developing Targhee rams, although Zn source elicited differential responses in performance characteristics measured.
Methodological approaches to situational analysis in global mental health: a scoping review
- J. K. Murphy, E. E. Michalak, H. Colquhoun, C. Woo, C. H. Ng, S. V. Parikh, L. Culpepper, C. S. Dewa, A. J. Greenshaw, Y. He, S. H. Kennedy, X.-M. Li, T. Liu, C. N. Soares, Z. Wang, Y. Xu, J. Chen, R. W. Lam
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- Journal:
- Global Mental Health / Volume 6 / 2019
- Published online by Cambridge University Press:
- 13 June 2019, e11
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Global inequity in access to and availability of essential mental health services is well recognized. The mental health treatment gap is approximately 50% in all countries, with up to 90% of people in the lowest-income countries lacking access to required mental health services. Increased investment in global mental health (GMH) has increased innovation in mental health service delivery in LMICs. Situational analyses in areas where mental health services and systems are poorly developed and resourced are essential when planning for research and implementation, however, little guidance is available to inform methodological approaches to conducting these types of studies. This scoping review provides an analysis of methodological approaches to situational analysis in GMH, including an assessment of the extent to which situational analyses include equity in study designs. It is intended as a resource that identifies current gaps and areas for future development in GMH. Formative research, including situational analysis, is an essential first step in conducting robust implementation research, an essential area of study in GMH that will help to promote improved availability of, access to and reach of mental health services for people living with mental illness in low- and middle-income countries (LMICs). While strong leadership in this field exists, there remain significant opportunities for enhanced research representing different LMICs and regions.
Effects of late gestation shearing on BW, feed intake and plasma metabolite concentrations in Rambouillet ewes managed outdoors during winter
- T. W. Murphy, W. C. Stewart, C. G. Smith, J. B. Taylor
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The majority of lambs in the United States are born from late winter to early spring and pregnant ewes are generally sheared in the last third of pregnancy. Although there are benefits to shearing before parturition, shorn animals may be more vulnerable to the cold, highly variable climatic conditions associated with these seasons. The objective of this study was to determine if late gestation shearing induces differences in individual BW, dry matter intake (DMI) and plasma metabolite concentration of finewool ewes managed outdoors during winter. Thirty-six mature, pregnant Rambouillet ewes (3.8±0.45 years; 76.8±11.4 kg) were managed in a drylot with ad libitum access to pelleted alfalfa in bunks capable of measuring individual daily DMI. The treatment group consisted of ewes sheared at ~5 weeks before the estimated parturition date (shorn; n=18). Unshorn ewes (n=18) remained in full fleece throughout the experiment and were shorn on the last day of the experiment ~2 weeks before the estimated parturition date. Blood was collected on days 0 (before shearing shorn group), 7, 14 and 21 (before shearing unshorn group) of the trial, and plasma was isolated and analyzed for non-esterified fatty acid (NEFA), β-hydroxybutyrate (BHB) and glucose (GLU) concentrations. There was no effect of shearing on ewe DMI or BW during the trial (P⩾0.35). Plasma NEFA and GLU concentrations were similar (P⩾0.36) between shearing groups, though plasma BHB concentration was 103.7 μmol/l greater (24.1%; P<0.01) in unshorn ewes. Lamb BW at birth was not affected (P=0.30) by ewe shearing treatment. Under conditions of this study, no differences in economically important aspects of sheep production were observed between shorn and unshorn pregnant ewes.
Follow Up of GW170817 and Its Electromagnetic Counterpart by Australian-Led Observing Programmes
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- I. Andreoni, K. Ackley, J. Cooke, A. Acharyya, J. R. Allison, G. E. Anderson, M. C. B. Ashley, D. Baade, M. Bailes, K. Bannister, A. Beardsley, M. S. Bessell, F. Bian, P. A. Bland, M. Boer, T. Booler, A. Brandeker, I. S. Brown, D. A. H. Buckley, S.-W. Chang, D. M. Coward, S. Crawford, H. Crisp, B. Crosse, A. Cucchiara, M. Cupák, J. S. de Gois, A. Deller, H. A. R. Devillepoix, D. Dobie, E. Elmer, D. Emrich, W. Farah, T. J. Farrell, T. Franzen, B. M. Gaensler, D. K. Galloway, B. Gendre, T. Giblin, A. Goobar, J. Green, P. J. Hancock, B. A. D. Hartig, E. J. Howell, L. Horsley, A. Hotan, R. M. Howie, L. Hu, Y. Hu, C. W. James, S. Johnston, M. Johnston-Hollitt, D. L. Kaplan, M. Kasliwal, E. F. Keane, D. Kenney, A. Klotz, R. Lau, R. Laugier, E. Lenc, X. Li, E. Liang, C. Lidman, L. C. Luvaul, C. Lynch, B. Ma, D. Macpherson, J. Mao, D. E. McClelland, C. McCully, A. Möller, M. F. Morales, D. Morris, T. Murphy, K. Noysena, C. A. Onken, N. B. Orange, S. Osłowski, D. Pallot, J. Paxman, S. B. Potter, T. Pritchard, W. Raja, R. Ridden-Harper, E. Romero-Colmenero, E. M. Sadler, E. K. Sansom, R. A. Scalzo, B. P. Schmidt, S. M. Scott, N. Seghouani, Z. Shang, R. M. Shannon, L. Shao, M. M. Shara, R. Sharp, M. Sokolowski, J. Sollerman, J. Staff, K. Steele, T. Sun, N. B. Suntzeff, C. Tao, S. Tingay, M. C. Towner, P. Thierry, C. Trott, B. E. Tucker, P. Väisänen, V. Venkatraman Krishnan, M. Walker, L. Wang, X. Wang, R. Wayth, M. Whiting, A. Williams, T. Williams, C. Wolf, C. Wu, X. Wu, J. Yang, X. Yuan, H. Zhang, J. Zhou, H. Zovaro
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 34 / 2017
- Published online by Cambridge University Press:
- 20 December 2017, e069
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The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
The UTMOST: A Hybrid Digital Signal Processor Transforms the Molonglo Observatory Synthesis Telescope
- M. Bailes, A. Jameson, C. Flynn, T. Bateman, E. D. Barr, S. Bhandari, J. D. Bunton, M. Caleb, D. Campbell-Wilson, W. Farah, B. Gaensler, A. J. Green, R. W. Hunstead, F. Jankowski, E. F. Keane, V. Venkatraman Krishnan, Tara Murphy, M. O’Neill, S. Osłowski, A. Parthasarathy, V. Ravi, P. Rosado, D. Temby
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- Publications of the Astronomical Society of Australia / Volume 34 / 2017
- Published online by Cambridge University Press:
- 13 October 2017, e045
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The Molonglo Observatory Synthesis Telescope (MOST) is an 18000 m2 radio telescope located 40 km from Canberra, Australia. Its operating band (820–851 MHz) is partly allocated to telecommunications, making radio astronomy challenging. We describe how the deployment of new digital receivers, Field Programmable Gate Array-based filterbanks, and server-class computers equipped with 43 Graphics Processing Units, has transformed the telescope into a versatile new instrument (UTMOST) for studying the radio sky on millisecond timescales. UTMOST has 10 times the bandwidth and double the field of view compared to the MOST, and voltage record and playback capability has facilitated rapid implementaton of many new observing modes, most of which operate commensally. UTMOST can simultaneously excise interference, make maps, coherently dedisperse pulsars, and perform real-time searches of coherent fan-beams for dispersed single pulses. UTMOST operates as a robotic facility, deciding how to efficiently target pulsars and how long to stay on source via real-time pulsar folding, while searching for single pulse events. Regular timing of over 300 pulsars has yielded seven pulsar glitches and three Fast Radio Bursts during commissioning. UTMOST demonstrates that if sufficient signal processing is applied to voltage streams, innovative science remains possible even in hostile radio frequency environments.
Expert System Evaluation and Implementation for Soybean (Glycine max) Weed Management
- C. Dale Monks, David C. Bridges, John W. Woodruff, Tim R. Murphy, Daniel J. Berry
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- Weed Technology / Volume 9 / Issue 3 / September 1995
- Published online by Cambridge University Press:
- 12 June 2017, pp. 535-540
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HERB, a computer-based expert system for soybean weed management developed at North Carolina State University, was evaluated for managing weeds under Georgia conditions. The project was initiated in two phases: a) training Cooperative Extension county agents followed by evaluation in six Georgia counties and b) revision, licensing, and distribution across the state. Field evaluations indicated that HERB was not highly accurate for predicting final yield loss because of weed species senescence and environmental extremes later in the growing season. HERB generally provided a reasonable prediction for a positive economic return due to treatment approximately 60% of the time. Accuracy was directly dependent upon the accuracy of weed-free yield estimates and extremes in growing conditions. HERB should not be the sole source of weed management information but may be useful to producers and county agents where mixed or low populations of weeds exist. The program was distributed statewide in 1993 after revision, duplication, and training was completed.
Modelling Ebola within a community
- R. N. LEANDER, W. S. GOFF, C. W. MURPHY, S. A. PULIDO
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- Journal:
- Epidemiology & Infection / Volume 144 / Issue 11 / August 2016
- Published online by Cambridge University Press:
- 28 March 2016, pp. 2329-2337
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The 2014 Ebola epidemic was the largest on record. It evidenced the need for improved models of the spread of Ebola. In this research we focus on modelling Ebola within a small village or community. Specifically, we investigate the potential of basic Susceptible-Exposed-Infectious-Recovered (SEIR) models to describe the initial Ebola outbreak, which occurred in Meliandou, Guinea. Data from the World Health Organization is used to compare the accuracy of various models in order to select the most accurate models of transmission and disease-induced responses. Our results suggest that (i) density-dependent transmission and mortality-induced behavioural changes shaped the course of the Ebola epidemic in Meliandou, while (ii) frequency-dependent transmission, disease-induced emigration, and infection-induced behavioural changes are not consistent with the data from this epidemic.
Gas Kinematics in the Multiphase Circumgalactic Medium
- Nikole M. Nielsen, Glenn G. Kacprzak, Christopher W. Churchill, Michael T. Murphy, Sowgat Muzahid, Jane C. Charlton, Jessica L. Evans
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- Journal:
- Proceedings of the International Astronomical Union / Volume 11 / Issue S321 / March 2016
- Published online by Cambridge University Press:
- 21 March 2017, pp. 345-347
- Print publication:
- March 2016
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We use high-resolution Keck, VLT, or Hubble Space Telescope spectra of background quasars to examine the kinematic properties of the multiphase, metal-enriched circumgalactic medium in the outskirts of galaxies at 0.08 < zgal < 1.0, focusing on the low-ionization Mgii and high-ionization Ovi doublets. The absorption kinematics of low-ionization gas in the circumgalactic medium depend strongly on the star formation activity and the location about the host galaxy, where the largest velocity dispersions are associated with blue, face-on galaxies probed along the minor axis. Conversely, high-ionization gas kinematics are independent of galaxy star formation activity and orientation.
Contributors
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- By Mitchell Aboulafia, Frederick Adams, Marilyn McCord Adams, Robert M. Adams, Laird Addis, James W. Allard, David Allison, William P. Alston, Karl Ameriks, C. Anthony Anderson, David Leech Anderson, Lanier Anderson, Roger Ariew, David Armstrong, Denis G. Arnold, E. J. Ashworth, Margaret Atherton, Robin Attfield, Bruce Aune, Edward Wilson Averill, Jody Azzouni, Kent Bach, Andrew Bailey, Lynne Rudder Baker, Thomas R. Baldwin, Jon Barwise, George Bealer, William Bechtel, Lawrence C. Becker, Mark A. Bedau, Ernst Behler, José A. Benardete, Ermanno Bencivenga, Jan Berg, Michael Bergmann, Robert L. Bernasconi, Sven Bernecker, Bernard Berofsky, Rod Bertolet, Charles J. Beyer, Christian Beyer, Joseph Bien, Joseph Bien, Peg Birmingham, Ivan Boh, James Bohman, Daniel Bonevac, Laurence BonJour, William J. Bouwsma, Raymond D. Bradley, Myles Brand, Richard B. Brandt, Michael E. Bratman, Stephen E. Braude, Daniel Breazeale, Angela Breitenbach, Jason Bridges, David O. Brink, Gordon G. Brittan, Justin Broackes, Dan W. Brock, Aaron Bronfman, Jeffrey E. Brower, Bartosz Brozek, Anthony Brueckner, Jeffrey Bub, Lara Buchak, Otavio Bueno, Ann E. Bumpus, Robert W. Burch, John Burgess, Arthur W. Burks, Panayot Butchvarov, Robert E. Butts, Marina Bykova, Patrick Byrne, David Carr, Noël Carroll, Edward S. Casey, Victor Caston, Victor Caston, Albert Casullo, Robert L. Causey, Alan K. L. Chan, Ruth Chang, Deen K. Chatterjee, Andrew Chignell, Roderick M. Chisholm, Kelly J. Clark, E. J. Coffman, Robin Collins, Brian P. Copenhaver, John Corcoran, John Cottingham, Roger Crisp, Frederick J. Crosson, Antonio S. Cua, Phillip D. Cummins, Martin Curd, Adam Cureton, Andrew Cutrofello, Stephen Darwall, Paul Sheldon Davies, Wayne A. Davis, Timothy Joseph Day, Claudio de Almeida, Mario De Caro, Mario De Caro, John Deigh, C. F. Delaney, Daniel C. Dennett, Michael R. DePaul, Michael Detlefsen, Daniel Trent Devereux, Philip E. Devine, John M. Dillon, Martin C. Dillon, Robert DiSalle, Mary Domski, Alan Donagan, Paul Draper, Fred Dretske, Mircea Dumitru, Wilhelm Dupré, Gerald Dworkin, John Earman, Ellery Eells, Catherine Z. Elgin, Berent Enç, Ronald P. Endicott, Edward Erwin, John Etchemendy, C. Stephen Evans, Susan L. Feagin, Solomon Feferman, Richard Feldman, Arthur Fine, Maurice A. Finocchiaro, William FitzPatrick, Richard E. Flathman, Gvozden Flego, Richard Foley, Graeme Forbes, Rainer Forst, Malcolm R. Forster, Daniel Fouke, Patrick Francken, Samuel Freeman, Elizabeth Fricker, Miranda Fricker, Michael Friedman, Michael Fuerstein, Richard A. Fumerton, Alan Gabbey, Pieranna Garavaso, Daniel Garber, Jorge L. A. Garcia, Robert K. Garcia, Don Garrett, Philip Gasper, Gerald Gaus, Berys Gaut, Bernard Gert, Roger F. Gibson, Cody Gilmore, Carl Ginet, Alan H. Goldman, Alvin I. Goldman, Alfonso Gömez-Lobo, Lenn E. Goodman, Robert M. Gordon, Stefan Gosepath, Jorge J. E. Gracia, Daniel W. Graham, George A. Graham, Peter J. Graham, Richard E. Grandy, I. Grattan-Guinness, John Greco, Philip T. Grier, Nicholas Griffin, Nicholas Griffin, David A. Griffiths, Paul J. Griffiths, Stephen R. Grimm, Charles L. Griswold, Charles B. Guignon, Pete A. Y. Gunter, Dimitri Gutas, Gary Gutting, Paul Guyer, Kwame Gyekye, Oscar A. Haac, Raul Hakli, Raul Hakli, Michael Hallett, Edward C. Halper, Jean Hampton, R. James Hankinson, K. R. Hanley, Russell Hardin, Robert M. Harnish, William Harper, David Harrah, Kevin Hart, Ali Hasan, William Hasker, John Haugeland, Roger Hausheer, William Heald, Peter Heath, Richard Heck, John F. Heil, Vincent F. Hendricks, Stephen Hetherington, Francis Heylighen, Kathleen Marie Higgins, Risto Hilpinen, Harold T. Hodes, Joshua Hoffman, Alan Holland, Robert L. Holmes, Richard Holton, Brad W. Hooker, Terence E. Horgan, Tamara Horowitz, Paul Horwich, Vittorio Hösle, Paul Hoβfeld, Daniel Howard-Snyder, Frances Howard-Snyder, Anne Hudson, Deal W. Hudson, Carl A. Huffman, David L. Hull, Patricia Huntington, Thomas Hurka, Paul Hurley, Rosalind Hursthouse, Guillermo Hurtado, Ronald E. Hustwit, Sarah Hutton, Jonathan Jenkins Ichikawa, Harry A. Ide, David Ingram, Philip J. Ivanhoe, Alfred L. Ivry, Frank Jackson, Dale Jacquette, Joseph Jedwab, Richard Jeffrey, David Alan Johnson, Edward Johnson, Mark D. Jordan, Richard Joyce, Hwa Yol Jung, Robert Hillary Kane, Tomis Kapitan, Jacquelyn Ann K. Kegley, James A. Keller, Ralph Kennedy, Sergei Khoruzhii, Jaegwon Kim, Yersu Kim, Nathan L. King, Patricia Kitcher, Peter D. Klein, E. D. Klemke, Virginia Klenk, George L. Kline, Christian Klotz, Simo Knuuttila, Joseph J. Kockelmans, Konstantin Kolenda, Sebastian Tomasz Kołodziejczyk, Isaac Kramnick, Richard Kraut, Fred Kroon, Manfred Kuehn, Steven T. Kuhn, Henry E. Kyburg, John Lachs, Jennifer Lackey, Stephen E. Lahey, Andrea Lavazza, Thomas H. Leahey, Joo Heung Lee, Keith Lehrer, Dorothy Leland, Noah M. Lemos, Ernest LePore, Sarah-Jane Leslie, Isaac Levi, Andrew Levine, Alan E. Lewis, Daniel E. Little, Shu-hsien Liu, Shu-hsien Liu, Alan K. L. Chan, Brian Loar, Lawrence B. Lombard, John Longeway, Dominic McIver Lopes, Michael J. Loux, E. J. Lowe, Steven Luper, Eugene C. Luschei, William G. Lycan, David Lyons, David Macarthur, Danielle Macbeth, Scott MacDonald, Jacob L. Mackey, Louis H. Mackey, Penelope Mackie, Edward H. Madden, Penelope Maddy, G. B. Madison, Bernd Magnus, Pekka Mäkelä, Rudolf A. Makkreel, David Manley, William E. Mann (W.E.M.), Vladimir Marchenkov, Peter Markie, Jean-Pierre Marquis, Ausonio Marras, Mike W. Martin, A. P. Martinich, William L. McBride, David McCabe, Storrs McCall, Hugh J. McCann, Robert N. McCauley, John J. McDermott, Sarah McGrath, Ralph McInerny, Daniel J. McKaughan, Thomas McKay, Michael McKinsey, Brian P. McLaughlin, Ernan McMullin, Anthonie Meijers, Jack W. Meiland, William Jason Melanson, Alfred R. Mele, Joseph R. Mendola, Christopher Menzel, Michael J. Meyer, Christian B. Miller, David W. Miller, Peter Millican, Robert N. Minor, Phillip Mitsis, James A. Montmarquet, Michael S. Moore, Tim Moore, Benjamin Morison, Donald R. Morrison, Stephen J. Morse, Paul K. Moser, Alexander P. D. Mourelatos, Ian Mueller, James Bernard Murphy, Mark C. Murphy, Steven Nadler, Jan Narveson, Alan Nelson, Jerome Neu, Samuel Newlands, Kai Nielsen, Ilkka Niiniluoto, Carlos G. Noreña, Calvin G. Normore, David Fate Norton, Nikolaj Nottelmann, Donald Nute, David S. Oderberg, Steve Odin, Michael O’Rourke, Willard G. Oxtoby, Heinz Paetzold, George S. Pappas, Anthony J. Parel, Lydia Patton, R. P. Peerenboom, Francis Jeffry Pelletier, Adriaan T. Peperzak, Derk Pereboom, Jaroslav Peregrin, Glen Pettigrove, Philip Pettit, Edmund L. Pincoffs, Andrew Pinsent, Robert B. Pippin, Alvin Plantinga, Louis P. Pojman, Richard H. Popkin, John F. Post, Carl J. Posy, William J. Prior, Richard Purtill, Michael Quante, Philip L. Quinn, Philip L. Quinn, Elizabeth S. Radcliffe, Diana Raffman, Gerard Raulet, Stephen L. Read, Andrews Reath, Andrew Reisner, Nicholas Rescher, Henry S. Richardson, Robert C. Richardson, Thomas Ricketts, Wayne D. Riggs, Mark Roberts, Robert C. Roberts, Luke Robinson, Alexander Rosenberg, Gary Rosenkranz, Bernice Glatzer Rosenthal, Adina L. Roskies, William L. Rowe, T. M. Rudavsky, Michael Ruse, Bruce Russell, Lilly-Marlene Russow, Dan Ryder, R. M. Sainsbury, Joseph Salerno, Nathan Salmon, Wesley C. Salmon, Constantine Sandis, David H. Sanford, Marco Santambrogio, David Sapire, Ruth A. Saunders, Geoffrey Sayre-McCord, Charles Sayward, James P. Scanlan, Richard Schacht, Tamar Schapiro, Frederick F. Schmitt, Jerome B. Schneewind, Calvin O. Schrag, Alan D. Schrift, George F. Schumm, Jean-Loup Seban, David N. Sedley, Kenneth Seeskin, Krister Segerberg, Charlene Haddock Seigfried, Dennis M. Senchuk, James F. Sennett, William Lad Sessions, Stewart Shapiro, Tommie Shelby, Donald W. Sherburne, Christopher Shields, Roger A. Shiner, Sydney Shoemaker, Robert K. Shope, Kwong-loi Shun, Wilfried Sieg, A. John Simmons, Robert L. Simon, Marcus G. Singer, Georgette Sinkler, Walter Sinnott-Armstrong, Matti T. Sintonen, Lawrence Sklar, Brian Skyrms, Robert C. Sleigh, Michael Anthony Slote, Hans Sluga, Barry Smith, Michael Smith, Robin Smith, Robert Sokolowski, Robert C. Solomon, Marta Soniewicka, Philip Soper, Ernest Sosa, Nicholas Southwood, Paul Vincent Spade, T. L. S. Sprigge, Eric O. Springsted, George J. Stack, Rebecca Stangl, Jason Stanley, Florian Steinberger, Sören Stenlund, Christopher Stephens, James P. Sterba, Josef Stern, Matthias Steup, M. A. Stewart, Leopold Stubenberg, Edith Dudley Sulla, Frederick Suppe, Jere Paul Surber, David George Sussman, Sigrún Svavarsdóttir, Zeno G. Swijtink, Richard Swinburne, Charles C. Taliaferro, Robert B. Talisse, John Tasioulas, Paul Teller, Larry S. Temkin, Mark Textor, H. S. Thayer, Peter Thielke, Alan Thomas, Amie L. Thomasson, Katherine Thomson-Jones, Joshua C. Thurow, Vzalerie Tiberius, Terrence N. Tice, Paul Tidman, Mark C. Timmons, William Tolhurst, James E. Tomberlin, Rosemarie Tong, Lawrence Torcello, Kelly Trogdon, J. D. Trout, Robert E. Tully, Raimo Tuomela, John Turri, Martin M. Tweedale, Thomas Uebel, Jennifer Uleman, James Van Cleve, Harry van der Linden, Peter van Inwagen, Bryan W. Van Norden, René van Woudenberg, Donald Phillip Verene, Samantha Vice, Thomas Vinci, Donald Wayne Viney, Barbara Von Eckardt, Peter B. M. Vranas, Steven J. Wagner, William J. Wainwright, Paul E. Walker, Robert E. Wall, Craig Walton, Douglas Walton, Eric Watkins, Richard A. Watson, Michael V. Wedin, Rudolph H. Weingartner, Paul Weirich, Paul J. Weithman, Carl Wellman, Howard Wettstein, Samuel C. Wheeler, Stephen A. White, Jennifer Whiting, Edward R. Wierenga, Michael Williams, Fred Wilson, W. Kent Wilson, Kenneth P. Winkler, John F. Wippel, Jan Woleński, Allan B. Wolter, Nicholas P. Wolterstorff, Rega Wood, W. Jay Wood, Paul Woodruff, Alison Wylie, Gideon Yaffe, Takashi Yagisawa, Yutaka Yamamoto, Keith E. Yandell, Xiaomei Yang, Dean Zimmerman, Günter Zoller, Catherine Zuckert, Michael Zuckert, Jack A. Zupko (J.A.Z.)
- Edited by Robert Audi, University of Notre Dame, Indiana
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- The Cambridge Dictionary of Philosophy
- Published online:
- 05 August 2015
- Print publication:
- 27 April 2015, pp ix-xxx
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Effects of elevating colonic propionate on liver fat content in overweight adults with non-alcoholic fatty liver disease: a pilot study
- E. S. Chambers, A. Viardot, A. Psichas, D. J. Morrison, K. G. Murphy, S. E. K. Zac-Varghese, K. MacDougall, T. Preston, M. C. Tedford, J. D. Bell, E. L. Thomas, S. Mt-Isa, D. Ashby, W. S. Dhillo, S. R. Bloom, W. G. Morley, S. Clegg, G. Frost
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- Journal:
- Proceedings of the Nutrition Society / Volume 74 / Issue OCE1 / 2015
- Published online by Cambridge University Press:
- 15 April 2015, E30
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Contributors
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- By Brittany L. Anderson-Montoya, Heather R. Bailey, Carryl L. Baldwin, Daphne Bavelier, Jameson D. Beach, Jeffrey S. Bedwell, Kevin B. Bennett, Richard A. Block, Deborah A. Boehm-Davis, Corey J. Bohil, David B. Boles, Avinoam Borowsky, Jessica Bramlett, Allison A. Brennan, J. Christopher Brill, Matthew S. Cain, Meredith Carroll, Roberto Champney, Kait Clark, Nancy J. Cooke, Lori M. Curtindale, Clare Davies, Patricia R. DeLucia, Andrew E. Deptula, Michael B. Dillard, Colin D. Drury, Christopher Edman, James T. Enns, Sara Irina Fabrikant, Victor S. Finomore, Arthur D. Fisk, John M. Flach, Matthew E. Funke, Andre Garcia, Adam Gazzaley, Douglas J. Gillan, Rebecca A. Grier, Simen Hagen, Kelly Hale, Diane F. Halpern, Peter A. Hancock, Deborah L. Harm, Mary Hegarty, Laurie M. Heller, Nicole D. Helton, William S. Helton, Robert R. Hoffman, Jerred Holt, Xiaogang Hu, Richard J. Jagacinski, Keith S. Jones, Astrid M. L. Kappers, Simon Kemp, Robert C. Kennedy, Robert S. Kennedy, Alan Kingstone, Ioana Koglbauer, Norman E. Lane, Robert D. Latzman, Cynthia Laurie-Rose, Patricia Lee, Richard Lowe, Valerie Lugo, Poornima Madhavan, Leonard S. Mark, Gerald Matthews, Jyoti Mishra, Stephen R. Mitroff, Tracy L. Mitzner, Alexander M. Morison, Taylor Murphy, Takamichi Nakamoto, John G. Neuhoff, Karl M. Newell, Tal Oron-Gilad, Raja Parasuraman, Tiffany A. Pempek, Robert W. Proctor, Katie A. Ragsdale, Anil K. Raj, Millard F. Reschke, Evan F. Risko, Matthew Rizzo, Wendy A. Rogers, Jesse Q. Sargent, Mark W. Scerbo, Natasha B. Schwartz, F. Jacob Seagull, Cory-Ann Smarr, L. James Smart, Kay Stanney, James Staszewski, Clayton L. Stephenson, Mary E. Stuart, Breanna E. Studenka, Joel Suss, Leedjia Svec, James L. Szalma, James Tanaka, James Thompson, Wouter M. Bergmann Tiest, Lauren A. Vassiliades, Michael A. Vidulich, Paul Ward, Joel S. Warm, David A. Washburn, Christopher D. Wickens, Scott J. Wood, David D. Woods, Motonori Yamaguchi, Lin Ye, Jeffrey M. Zacks
- Edited by Robert R. Hoffman, Peter A. Hancock, University of Central Florida, Mark W. Scerbo, Old Dominion University, Virginia, Raja Parasuraman, George Mason University, Virginia, James L. Szalma, University of Central Florida
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- The Cambridge Handbook of Applied Perception Research
- Published online:
- 05 July 2015
- Print publication:
- 26 January 2015, pp xi-xiv
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Phosphorus balance and use efficiency on 21 intensive grass-based dairy farms in the South of Ireland
- E. MIHAILESCU, P. N. C. MURPHY, W. RYAN, I. A. CASEY, J. HUMPHREYS
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- Journal:
- The Journal of Agricultural Science / Volume 153 / Issue 3 / April 2015
- Published online by Cambridge University Press:
- 02 September 2014, pp. 520-537
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Given the finite nature of global phosphorus (P) resources, there is an increasing concern about balancing agronomic and environmental impacts from P usage on dairy farms. Data from a 3-year (2009–2011) survey were used to assess farm-gate P balances and P use efficiency (PUE) on 21 intensive grass-based dairy farms operating under the good agricultural practice (GAP) regulations in Ireland. Mean stocking rate (SR) was 2·06 livestock units (LU)/ha, mean P surplus was 5·09 kg/ha, or 0·004 kg P/kg milk solids (MS), and mean PUE was 0·70. Phosphorus imports were dominated by inorganic fertilizer (7·61 kg P/ha) and feeds (7·62 kg P/ha), while exports were dominated by milk (6·66 kg P/ha) and livestock (5·10 kg P/ha). Comparison to similar studies carried out before the introduction of the GAP regulations in 2006 indicated that P surplus, both per ha and per kg MS, has significantly decreased (by 74 and 81%, respectively) and PUE increased (by 48%), mostly due to decreased inorganic fertilizer P import and improvements in P management. There has been a notable shift towards spring application of organic manures, indicating improved awareness of the fertilizer value of organic manures and good compliance with the GAP regulations regarding fertilizer application timing. These results suggested a positive impact of the GAP regulations on dairy farm P surplus and PUE, indicating an improvement in both environmental and economic sustainability of dairy production through improved resource use efficiencies. Such improvements will be necessary to achieve national targets of improved water quality and increased dairy production. Results suggest that optimizing fertilizer and feed P imports combined with improved on-farm P recycling are the most effective way to increase PUE. Equally, continued monitoring of soil test P (STP) and P management will be necessary to ensure that adequate soil P fertility is maintained. Mean P surplus was lower and PUE was much higher than the overall mean surplus (15·92 kg P/ha) and PUE (0·47) from three studies of continental and English dairy farms, largely due to the low import system that is more typical in Ireland, with seasonal milk production (compact spring calving), low use of imported feeds and high use of grazed grass.