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Science with the Murchison Widefield Array: Phase I results and Phase II opportunities – Corrigendum
- A. P. Beardsley, M. Johnston-Hollitt, C. M. Trott, J. C. Pober, J. Morgan, D. Oberoi, D. L. Kaplan, C. R. Lynch, G. E. Anderson, P. I. McCauley, S. Croft, C. W. James, O. I. Wong, C. D. Tremblay, R. P. Norris, I. H. Cairns, C. J. Lonsdale, P. J. Hancock, B. M. Gaensler, N. D. R. Bhat, W. Li, N. Hurley-Walker, J. R. Callingham, N. Seymour, S. Yoshiura, R. C. Joseph, K. Takahashi, M. Sokolowski, J. C. A. Miller-Jones, J. V. Chauhan, I. Bojičić, M. D. Filipović, D. Leahy, H. Su, W. W. Tian, S. J. McSweeney, B. W. Meyers, S. Kitaeff, T. Vernstrom, G. Gürkan, G. Heald, M. Xue, C. J. Riseley, S. W. Duchesne, J. D. Bowman, D. C. Jacobs, B. Crosse, D. Emrich, T. M. O. Franzen, L. Horsley, D. Kenney, M. F. Morales, D. Pallot, K. Steele, S. J. Tingay, M. Walker, R. B. Wayth, A. Williams, C. Wu
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- Publications of the Astronomical Society of Australia / Volume 37 / 2020
- Published online by Cambridge University Press:
- 23 March 2020, e014
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Science with the Murchison Widefield Array: Phase I results and Phase II opportunities
- A. P. Beardsley, M. Johnston-Hollitt, C. M. Trott, J. C. Pober, J. Morgan, D. Oberoi, D. L. Kaplan, C. R. Lynch, G. E. Anderson, P. I. McCauley, S. Croft, C. W. James, O. I. Wong, C. D. Tremblay, R. P. Norris, I. H. Cairns, C. J. Lonsdale, P. J. Hancock, B. M. Gaensler, N. D. R. Bhat, W. Li, N. Hurley-Walker, J. R. Callingham, N. Seymour, S. Yoshiura, R. C. Joseph, K. Takahashi, M. Sokolowski, J. C. A. Miller-Jones, J. V. Chauhan, I. Bojičić, M. D. Filipović, D. Leahy, H. Su, W. W. Tian, S. J. McSweeney, B. W. Meyers, S. Kitaeff, T. Vernstrom, G. Gürkan, G. Heald, M. Xue, C. J. Riseley, S. W. Duchesne, J. D. Bowman, D. C. Jacobs, B. Crosse, D. Emrich, T. M. O. Franzen, L. Horsley, D. Kenney, M. F. Morales, D. Pallot, K. Steele, S. J. Tingay, M. Walker, R. B. Wayth, A. Williams, C. Wu
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- Publications of the Astronomical Society of Australia / Volume 36 / 2019
- Published online by Cambridge University Press:
- 13 December 2019, e050
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The Murchison Widefield Array (MWA) is an open access telescope dedicated to studying the low-frequency (80–300 MHz) southern sky. Since beginning operations in mid-2013, the MWA has opened a new observational window in the southern hemisphere enabling many science areas. The driving science objectives of the original design were to observe 21 cm radiation from the Epoch of Reionisation (EoR), explore the radio time domain, perform Galactic and extragalactic surveys, and monitor solar, heliospheric, and ionospheric phenomena. All together $60+$ programs recorded 20 000 h producing 146 papers to date. In 2016, the telescope underwent a major upgrade resulting in alternating compact and extended configurations. Other upgrades, including digital back-ends and a rapid-response triggering system, have been developed since the original array was commissioned. In this paper, we review the major results from the prior operation of the MWA and then discuss the new science paths enabled by the improved capabilities. We group these science opportunities by the four original science themes but also include ideas for directions outside these categories.
Effects of trace mineral amount and source on aspects of oxidative metabolism and responses to intramammary lipopolysaccharide challenge in midlactation dairy cows
- T. Yasui, R. M. Ehrhardt, G. R. Bowman, M. Vázquez-Añon, J. D. Richards, C. A. Atwell, T. R. Overton
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Trace minerals have important roles in immune function and oxidative metabolism; however, little is known about the relationships between supplementation level and source with outcomes in dairy cattle. Multiparous Holstein cows (n=48) beginning at 60 to 140 days in milk were utilized to determine the effects of trace mineral amount and source on aspects of oxidative metabolism and responses to intramammary lipopolysaccharide (LPS) challenge. Cows were fed a basal diet meeting National Research Council (NRC) requirements except for no added zinc (Zn), copper (Cu) or manganese (Mn). After a 4-week preliminary period, cows were assigned to one of four topdress treatments in a randomized complete block design with a 2×2 factorial arrangement of treatments: (1) NRC inorganic (NRC levels using inorganic (sulfate-based) trace mineral supplements only); (2) NRC organic (NRC levels using organic trace mineral supplements (metals chelated to 2-hydroxy-4-(methythio)-butanoic acid); (3) commercial inorganic (approximately 2×NRC levels using inorganic trace mineral supplements only; and (4) commercial organic (commercial levels using organic trace mineral supplements only). Cows were fed the respective mineral treatments for 6 weeks. Treatment effects were level, source and their interaction. Activities of super oxide dismutase and glutathione peroxidase in erythrocyte lysate and concentrations of thiobarbituric acid reactive substances (TBARS) and total antioxidant capacity (TAC) in plasma were measured as indices of oxidative metabolism. Effects of treatment on those indices were not significant when evaluated across the entire experimental period. Plasma immunoglobulin G level was higher in cows supplemented with organic trace minerals over the entire treatment period; responses assessed as differences of before and after Escherichia coli J5 bacterin vaccination at the end of week 2 of treatment period were not significant. Cows were administered an intramammary LPS challenge during week 5; during week 6 cows fed commercial levels of Zn, Cu and Mn tended to have higher plasma TAC and cows fed organic sources had decreased plasma TBARS. After the LPS challenge, the extent and pattern of response of plasma cortisol concentrations and clinical indices (rectal temperature and heart rate) were not affected by trace mineral level and source. Productive performance including dry matter intake and milk yield and composition were not affected by treatment. Overall, results suggest that the varying level and source of dietary trace minerals do not have significant short-term effects on oxidative metabolism indices and clinical responses to intramammary LPS challenge in midlactation cows.
A Large-Scale, Low-Frequency Murchison Widefield Array Survey of Galactic H ii Regions between 260 < l < 340
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- L. Hindson, M. Johnston-Hollitt, N. Hurley-Walker, J. R. Callingham, H. Su, J. Morgan, M. Bell, G. Bernardi, J. D. Bowman, F. Briggs, R. J. Cappallo, A. A. Deshpande, K. S. Dwarakanath, B.-Q For, B. M. Gaensler, L. J. Greenhill, P. Hancock, B. J. Hazelton, A. D. Kapińska, D. L. Kaplan, E. Lenc, C. J. Lonsdale, B. Mckinley, S. R. McWhirter, D. A. Mitchell, M. F. Morales, E. Morgan, D. Oberoi, A. Offringa, S. M. Ord, P. Procopio, T. Prabu, N. Udaya Shankar, K. S. Srivani, L. Staveley-Smith, R. Subrahmanyan, S. J. Tingay, R. B. Wayth, R. L. Webster, A. Williams, C. L. Williams, C. Wu, Q. Zheng
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 33 / 2016
- Published online by Cambridge University Press:
- 17 May 2016, e020
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We have compiled a catalogue of H ii regions detected with the Murchison Widefield Array between 72 and 231 MHz. The multiple frequency bands provided by the Murchison Widefield Array allow us identify the characteristic spectrum generated by the thermal Bremsstrahlung process in H ii regions. We detect 306 H ii regions between 260° < l < 340° and report on the positions, sizes, peak, integrated flux density, and spectral indices of these H ii regions. By identifying the point at which H ii regions transition from the optically thin to thick regime, we derive the physical properties including the electron density, ionised gas mass, and ionising photon flux, towards 61 H ii regions. This catalogue of H ii regions represents the most extensive and uniform low frequency survey of H ii regions in the Galaxy to date.
Ionospheric Modelling using GPS to Calibrate the MWA. I: Comparison of First Order Ionospheric Effects between GPS Models and MWA Observations
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- B. S. Arora, J. Morgan, S. M. Ord, S. J. Tingay, N. Hurley-Walker, M. Bell, G. Bernardi, N. D. R. Bhat, F. Briggs, J. R. Callingham, A. A. Deshpande, K. S. Dwarakanath, A. Ewall-Wice, L. Feng, B.-Q. For, P. Hancock, B. J. Hazelton, L. Hindson, D. Jacobs, M. Johnston-Hollitt, A. D. Kapińska, N. Kudryavtseva, E. Lenc, B. McKinley, D. Mitchell, D. Oberoi, A. R. Offringa, B. Pindor, P. Procopio, J. Riding, L. Staveley-Smith, R. B. Wayth, C. Wu, Q. Zheng, J. D. Bowman, R. J. Cappallo, B. E. Corey, D. Emrich, R. Goeke, L. J. Greenhill, D. L. Kaplan, J. C. Kasper, E. Kratzenberg, C. J. Lonsdale, M. J. Lynch, S. R. McWhirter, M. F. Morales, E. Morgan, T. Prabu, A. E. E. Rogers, A. Roshi, N. Udaya Shankar, K. S. Srivani, R. Subrahmanyan, M. Waterson, R. L. Webster, A. R. Whitney, A. Williams, and C. L. Williams
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- Publications of the Astronomical Society of Australia / Volume 32 / 2015
- Published online by Cambridge University Press:
- 10 August 2015, e029
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We compare first-order (refractive) ionospheric effects seen by the MWA with the ionosphere as inferred from GPS data. The first-order ionosphere manifests itself as a bulk position shift of the observed sources across an MWA field of view. These effects can be computed from global ionosphere maps provided by GPS analysis centres, namely the CODE. However, for precision radio astronomy applications, data from local GPS networks needs to be incorporated into ionospheric modelling. For GPS observations, the ionospheric parameters are biased by GPS receiver instrument delays, among other effects, also known as receiver DCBs. The receiver DCBs need to be estimated for any non-CODE GPS station used for ionosphere modelling. In this work, single GPS station-based ionospheric modelling is performed at a time resolution of 10 min. Also the receiver DCBs are estimated for selected Geoscience Australia GPS receivers, located at Murchison Radio Observatory, Yarragadee, Mount Magnet and Wiluna. The ionospheric gradients estimated from GPS are compared with that inferred from MWA. The ionospheric gradients at all the GPS stations show a correlation with the gradients observed with the MWA. The ionosphere estimates obtained using GPS measurements show promise in terms of providing calibration information for the MWA.
Off-Axis Electron Holography for the Quantitative Study of Magnetic Properties of Nanostructures: From the Single Nanomagnet to the Complex Device
- C. Gatel, A. Masseboeuf, E. Snoeck, F. Bonnilla, T. Blon, L.-M. Lacroix, A. Meffre, J.F. Einsle, R.M. Bowman, M.A. Bashir, M. Gubbins
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- Microscopy and Microanalysis / Volume 21 / Issue S3 / August 2015
- Published online by Cambridge University Press:
- 23 September 2015, pp. 2147-2148
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- August 2015
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GLEAM: The GaLactic and Extragalactic All-Sky MWA Survey
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- R. B. Wayth, E. Lenc, M. E. Bell, J. R. Callingham, K. S. Dwarakanath, T. M. O. Franzen, B.-Q. For, B. Gaensler, P. Hancock, L. Hindson, N. Hurley-Walker, C. A. Jackson, M. Johnston-Hollitt, A. D. Kapińska, B. McKinley, J. Morgan, A. R. Offringa, P. Procopio, L. Staveley-Smith, C. Wu, Q. Zheng, C. M. Trott, G. Bernardi, J. D. Bowman, F. Briggs, R. J. Cappallo, B. E. Corey, A. A. Deshpande, D. Emrich, R. Goeke, L. J. Greenhill, B. J. Hazelton, D. L. Kaplan, J. C. Kasper, E. Kratzenberg, C. J. Lonsdale, M. J. Lynch, S. R. McWhirter, D. A. Mitchell, M. F. Morales, E. Morgan, D. Oberoi, S. M. Ord, T. Prabu, A. E. E. Rogers, A. Roshi, N. Udaya Shankar, K. S. Srivani, R. Subrahmanyan, S. J. Tingay, M. Waterson, R. L. Webster, A. R. Whitney, A. Williams, C. L. Williams
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- Publications of the Astronomical Society of Australia / Volume 32 / 2015
- Published online by Cambridge University Press:
- 22 June 2015, e025
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GLEAM, the GaLactic and Extragalactic All-sky MWA survey, is a survey of the entire radio sky south of declination + 25° at frequencies between 72 and 231 MHz, made with the MWA using a drift scan method that makes efficient use of the MWA’s very large field-of-view. We present the observation details, imaging strategies, and theoretical sensitivity for GLEAM. The survey ran for two years, the first year using 40-kHz frequency resolution and 0.5-s time resolution; the second year using 10-kHz frequency resolution and 2 s time resolution. The resulting image resolution and sensitivity depends on observing frequency, sky pointing, and image weighting scheme. At 154 MHz, the image resolution is approximately 2.5 × 2.2/cos (δ + 26.7°) arcmin with sensitivity to structures up to ~ 10° in angular size. We provide tables to calculate the expected thermal noise for GLEAM mosaics depending on pointing and frequency and discuss limitations to achieving theoretical noise in Stokes I images. We discuss challenges, and their solutions, that arise for GLEAM including ionospheric effects on source positions and linearly polarised emission, and the instrumental polarisation effects inherent to the MWA’s primary beam.
The Murchison Widefield Array Correlator
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- S. M. Ord, B. Crosse, D. Emrich, D. Pallot, R. B. Wayth, M. A. Clark, S. E. Tremblay, W. Arcus, D. Barnes, M. Bell, G. Bernardi, N. D. R. Bhat, J. D. Bowman, F. Briggs, J. D. Bunton, R. J. Cappallo, B. E. Corey, A. A. Deshpande, L. deSouza, A. Ewell-Wice, L. Feng, R. Goeke, L. J. Greenhill, B. J. Hazelton, D. Herne, J. N. Hewitt, L. Hindson, N. Hurley-Walker, D. Jacobs, M. Johnston-Hollitt, D. L. Kaplan, J. C. Kasper, B. B. Kincaid, R. Koenig, E. Kratzenberg, N. Kudryavtseva, E. Lenc, C. J. Lonsdale, M. J. Lynch, B. McKinley, S. R. McWhirter, D. A. Mitchell, M. F. Morales, E. Morgan, D. Oberoi, A. Offringa, J. Pathikulangara, B. Pindor, T. Prabu, P. Procopio, R. A. Remillard, J. Riding, A. E. E. Rogers, A. Roshi, J. E. Salah, R. J. Sault, N. Udaya Shankar, K. S. Srivani, J. Stevens, R. Subrahmanyan, S. J. Tingay, M. Waterson, R. L. Webster, A. R. Whitney, A. Williams, C. L. Williams, J. S. B. Wyithe
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- Publications of the Astronomical Society of Australia / Volume 32 / 2015
- Published online by Cambridge University Press:
- 04 March 2015, e006
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The Murchison Widefield Array is a Square Kilometre Array Precursor. The telescope is located at the Murchison Radio–astronomy Observatory in Western Australia. The MWA consists of 4 096 dipoles arranged into 128 dual polarisation aperture arrays forming a connected element interferometer that cross-correlates signals from all 256 inputs. A hybrid approach to the correlation task is employed, with some processing stages being performed by bespoke hardware, based on Field Programmable Gate Arrays, and others by Graphics Processing Units housed in general purpose rack mounted servers. The correlation capability required is approximately 8 tera floating point operations per second. The MWA has commenced operations and the correlator is generating 8.3 TB day−1 of correlation products, that are subsequently transferred 700 km from the MRO to Perth (WA) in real-time for storage and offline processing. In this paper, we outline the correlator design, signal path, and processing elements and present the data format for the internal and external interfaces.
The Low-Frequency Environment of the Murchison Widefield Array: Radio-Frequency Interference Analysis and Mitigation
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- A. R. Offringa, R. B. Wayth, N. Hurley-Walker, D. L. Kaplan, N. Barry, A. P. Beardsley, M. E. Bell, G. Bernardi, J. D. Bowman, F. Briggs, J. R. Callingham, R. J. Cappallo, P. Carroll, A. A. Deshpande, J. S. Dillon, K. S. Dwarakanath, A. Ewall-Wice, L. Feng, B.-Q. For, B. M. Gaensler, L. J. Greenhill, P. Hancock, B. J. Hazelton, J. N. Hewitt, L. Hindson, D. C. Jacobs, M. Johnston-Hollitt, A. D. Kapińska, H.-S. Kim, P. Kittiwisit, E. Lenc, J. Line, A. Loeb, C. J. Lonsdale, B. McKinley, S. R. McWhirter, D. A. Mitchell, M. F. Morales, E. Morgan, J. Morgan, A. R. Neben, D. Oberoi, S. M. Ord, S. Paul, B. Pindor, J. C. Pober, T. Prabu, P. Procopio, J. Riding, N. Udaya Shankar, S. Sethi, K. S. Srivani, L. Staveley-Smith, R. Subrahmanyan, I. S. Sullivan, M. Tegmark, N. Thyagarajan, S. J. Tingay, C. M. Trott, R. L. Webster, A. Williams, C. L. Williams, C. Wu, J. S. Wyithe, Q. Zheng
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- Publications of the Astronomical Society of Australia / Volume 32 / 2015
- Published online by Cambridge University Press:
- 03 March 2015, e008
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The Murchison Widefield Array is a new low-frequency interferometric radio telescope built in Western Australia at one of the locations of the future Square Kilometre Array. We describe the automated radio-frequency interference detection strategy implemented for the Murchison Widefield Array, which is based on the aoflagger platform, and present 72–231 MHz radio-frequency interference statistics from 10 observing nights. Radio-frequency interference detection removes 1.1% of the data. Radio-frequency interference from digital TV is observed 3% of the time due to occasional ionospheric or atmospheric propagation. After radio-frequency interference detection and excision, almost all data can be calibrated and imaged without further radio-frequency interference mitigation efforts, including observations within the FM and digital TV bands. The results are compared to a previously published Low-Frequency Array radio-frequency interference survey. The remote location of the Murchison Widefield Array results in a substantially cleaner radio-frequency interference environment compared to Low-Frequency Array’s radio environment, but adequate detection of radio-frequency interference is still required before data can be analysed. We include specific recommendations designed to make the Square Kilometre Array more robust to radio-frequency interference, including: the availability of sufficient computing power for radio-frequency interference detection; accounting for radio-frequency interference in the receiver design; a smooth band-pass response; and the capability of radio-frequency interference detection at high time and frequency resolution (second and kHz-scale respectively).
The High Time and Frequency Resolution Capabilities of the Murchison Widefield Array
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- S. E. Tremblay, S. M. Ord, N. D. R. Bhat, S. J. Tingay, B. Crosse, D. Pallot, S. I. Oronsaye, G. Bernardi, J. D. Bowman, F. Briggs, R. J. Cappallo, B. E. Corey, A. A. Deshpande, D. Emrich, R. Goeke, L. J. Greenhill, B. J. Hazelton, M. Johnston-Hollitt, D. L. Kaplan, J. C. Kasper, E. Kratzenberg, C. J. Lonsdale, M. J. Lynch, S. R. McWhirter, D. A. Mitchell, M. F. Morales, E. Morgan, D. Oberoi, T. Prabu, A. E. E. Rogers, A. Roshi, N. Udaya Shankar, K. S. Srivani, R. Subrahmanyan, M. Waterson, R. B. Wayth, R. L. Webster, A. R. Whitney, A. Williams, C. L. Williams
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- Publications of the Astronomical Society of Australia / Volume 32 / 2015
- Published online by Cambridge University Press:
- 26 February 2015, e005
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The science cases for incorporating high time resolution capabilities into modern radio telescopes are as numerous as they are compelling. Science targets range from exotic sources such as pulsars, to our Sun, to recently detected possible extragalactic bursts of radio emission, the so-called fast radio bursts (FRBs). Originally conceived purely as an imaging telescope, the initial design of the Murchison Widefield Array (MWA) did not include the ability to access high time and frequency resolution voltage data. However, the flexibility of the MWA’s software correlator allowed an off-the-shelf solution for adding this capability. This paper describes the system that records the 100 μs and 10 kHz resolution voltage data from the MWA. Example science applications, where this capability is critical, are presented, as well as accompanying commissioning results from this mode to demonstrate verification.
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- By Masoud Azodi, Patricia Baetens, Steven Bayer, Joel Bernstein, Jonathan D. Black, Christophe Blockeel, Carolien M. Boomsma, Birgit Borgström, Mark Bowman, Nicholas Brook, Elisabeth Carlsen, Peter Carne, Ying Cheong, Jen-Ruei Chen, Erin Clark, S. Alberto Dávila Garza, Sunita De Sousa, Michel De Vos, Leo Doherty, Patricio Donoso, Cindy M. P. Duke, Human M. Fatemi, Alison Fernbach, Juan A. Garcia-Velasco, Elizabeth S. Ginsburg, Dorothy A. Greenfeld, William M. Hague, Daniel Hajioff, Tristan Hardy, Catherine Henry, Outi Hovatta, John Hutton, Gordana Ivanovic, Sameer Jatkar, Shilpa Jesudason, Theo Joseph, Amanda Kallen, Sonal Karia, Bala Karunakaran, Jenneke C. Kasius, Ben Kroon, Dimitra Kyrou, Robert Lahoud, Jennifer M Levine, Inge Liebaers, Shane T. Lipskind, Derek Lok, Nick S. Macklon, Manveen (Manny) Mangat, Tom P. Manolitsas, S. McDowell, Cherise Mooy, Mark R. Morton, Andrew Murray, Robert J. Norman, Sara Ornaghi, Israel Ortega, Michael J. Paidas, Evaggelos Papanikolaou, Pasquale Patrizio, Sofie Piessens, Biljana Popovic Todorovic, Luk Rombauts, Katrina Rowan, Denny Sakkas, P. Sanhueza, Kirsten Tryde Schmidt, Mark Teoh, Hammed A. Tijani, Jelena Todorovic, Saioa Torrealday, Herman Tournaye, Geoffrey Trew, W. Verpoest, Veerle Vloeberghs, A. Yazdani
- Edited by Nick S. Macklon, University of Southampton, Human M. Fatemi, Robert J. Norman, University of Adelaide, Pasquale Patrizio
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- Case Studies in Assisted Reproduction
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- 05 February 2015
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- 22 January 2015, pp ix-xiv
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The Murchison Widefield Array: The Square Kilometre Array Precursor at Low Radio Frequencies
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- S. J. Tingay, R. Goeke, J. D. Bowman, D. Emrich, S. M. Ord, D. A. Mitchell, M. F. Morales, T. Booler, B. Crosse, R. B. Wayth, C. J. Lonsdale, S. Tremblay, D. Pallot, T. Colegate, A. Wicenec, N. Kudryavtseva, W. Arcus, D. Barnes, G. Bernardi, F. Briggs, S. Burns, J. D. Bunton, R. J. Cappallo, B. E. Corey, A. Deshpande, L. Desouza, B. M. Gaensler, L. J. Greenhill, P. J. Hall, B. J. Hazelton, D. Herne, J. N. Hewitt, M. Johnston-Hollitt, D. L. Kaplan, J. C. Kasper, B. B. Kincaid, R. Koenig, E. Kratzenberg, M. J. Lynch, B. Mckinley, S. R. Mcwhirter, E. Morgan, D. Oberoi, J. Pathikulangara, T. Prabu, R. A. Remillard, A. E. E. Rogers, A. Roshi, J. E. Salah, R. J. Sault, N. Udaya-Shankar, F. Schlagenhaufer, K. S. Srivani, J. Stevens, R. Subrahmanyan, M. Waterson, R. L. Webster, A. R. Whitney, A. Williams, C. L. Williams, J. S. B. Wyithe
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- Publications of the Astronomical Society of Australia / Volume 30 / 2013
- Published online by Cambridge University Press:
- 24 January 2013, e007
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The Murchison Widefield Array (MWA) is one of three Square Kilometre Array Precursor telescopes and is located at the Murchison Radio-astronomy Observatory in the Murchison Shire of the mid-west of Western Australia, a location chosen for its extremely low levels of radio frequency interference. The MWA operates at low radio frequencies, 80–300 MHz, with a processed bandwidth of 30.72 MHz for both linear polarisations, and consists of 128 aperture arrays (known as tiles) distributed over a ~3-km diameter area. Novel hybrid hardware/software correlation and a real-time imaging and calibration systems comprise the MWA signal processing backend. In this paper, the as-built MWA is described both at a system and sub-system level, the expected performance of the array is presented, and the science goals of the instrument are summarised.
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- By Mohamed Aboulghar, Ahmed Abou-Setta, Mary E. Abusief, G. David Adamson, R. J. Aitken, Hesham Al-Inany, Baris Ata, Hamdy Azab, Adam Balen, David H. Barad, Pedro N. Barri, C. Blockeel, Giuseppe Botta, Mark Bowman, Chris Brewer, Dominique M. Butawan, Sandra A. Carson, Hai Ying Chen, Anne Clark, Buenaventura Coroleu, S. Das, C. Dechanet, H. Déchaud, Cora de Klerk, Sheryl de Lacey, S. Deutsch-Bringer, P. Devroey, Didier Dewailly, Hakan E. Duran, Walid El Sherbiny, Tarek El-Toukhy, Johannes L. H. Evers, Cynthia Farquhar, Rodney D. Franklin, Juan A. Garcia-Velasco, David K. Gardner, Norbert Gleicher, Gedis Grudzinskas, Roger Hart, B Hédon, Colin M. Howles, Jack Yu Jen Huang, N. P. Johnson, Hey-Joo Kang, Gab Kovacs, Ben Kroon, Anver Kuliev, William H. Kutteh, Nick Macklon, Ragaa Mansour, Lamiya Mohiyiddeen, Lisa J. Moran, David Mortimer, Sharon T. Mortimer, Luciano G. Nardo, Robert J. Norman, Willem Ombelet, Luk Rombauts, Zev Rosenwaks, Francisco J. Ruiz Flores, Anthony J. Rutherford, Gavin Sacks, Denny Sakkas, M. W. Seif, Ayse Seyhan, Caroline Smith, Kate Stern, Elizabeth A. Sullivan, Sesh Kamal Sunkara, Seang Lin Tan, Mohamed Taranissi, Kelton P. Tremellen, Wendy S. Vitek, V. Vloeberghs, Bradley J. Van Voorhis, S. F. van Voorst, Amr Wahba, Yueping A. Wang, Klaus E. Wiemer
- Edited by Gab Kovacs, Monash University, Victoria
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- How to Improve your ART Success Rates
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- 05 July 2011
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- 30 June 2011, pp viii-xii
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. Hackett, Getatchew Haile, Douglas John Hall, Nicholas Hammond, Daphne Hampson, Jehu J. Hanciles, Barry Hankins, Jennifer Haraguchi, Stanley S. Harakas, Anthony John Harding, Conrad L. Harkins, J. William Harmless, Marjory Harper, Amir Harrak, Joel F. Harrington, Mark W. Harris, Susan Ashbrook Harvey, Van A. Harvey, R. Chris Hassel, Jione Havea, Daniel Hawk, Diana L. Hayes, Leslie Hayes, Priscilla Hayner, S. Mark Heim, Simo Heininen, Richard P. Heitzenrater, Eila Helander, David Hempton, Scott H. Hendrix, Jan-Olav Henriksen, Gina Hens-Piazza, Carter Heyward, Nicholas J. Higham, David Hilliard, Norman A. Hjelm, Peter C. Hodgson, Arthur Holder, M. Jan Holton, Dwight N. Hopkins, Ronnie Po-chia Hsia, Po-Ho Huang, James Hudnut-Beumler, Jennifer S. Hughes, Leonard M. Hummel, Mary E. Hunt, Laennec Hurbon, Mark Hutchinson, Susan E. Hylen, Mary Beth Ingham, H. Larry Ingle, Dale T. Irvin, Jon Isaak, Paul John Isaak, Ada María Isasi-Díaz, Hans Raun Iversen, Margaret C. Jacob, Arthur James, Maria Jansdotter-Samuelsson, David Jasper, Werner G. Jeanrond, Renée Jeffery, David Lyle Jeffrey, Theodore W. Jennings, David H. Jensen, Robin Margaret Jensen, David Jobling, Dale A. Johnson, Elizabeth A. Johnson, Maxwell E. Johnson, Sarah Johnson, Mark D. Johnston, F. Stanley Jones, James William Jones, John R. Jones, Alissa Jones Nelson, Inge Jonsson, Jan Joosten, Elizabeth Judd, Mulambya Peggy Kabonde, Robert Kaggwa, Sylvester Kahakwa, Isaac Kalimi, Ogbu U. Kalu, Eunice Kamaara, Wayne C. Kannaday, Musimbi Kanyoro, Veli-Matti Kärkkäinen, Frank Kaufmann, Léon Nguapitshi Kayongo, Richard Kearney, Alice A. Keefe, Ralph Keen, Catherine Keller, Anthony J. Kelly, Karen Kennelly, Kathi Lynn Kern, Fergus Kerr, Edward Kessler, George Kilcourse, Heup Young Kim, Kim Sung-Hae, Kim Yong-Bock, Kim Yung Suk, Richard King, Thomas M. King, Robert M. Kingdon, Ross Kinsler, Hans G. Kippenberg, Cheryl A. Kirk-Duggan, Clifton Kirkpatrick, Leonid Kishkovsky, Nadieszda Kizenko, Jeffrey Klaiber, Hans-Josef Klauck, Sidney Knight, Samuel Kobia, Robert Kolb, Karla Ann Koll, Heikki Kotila, Donald Kraybill, Philip D. W. Krey, Yves Krumenacker, Jeffrey Kah-Jin Kuan, Simanga R. Kumalo, Peter Kuzmic, Simon Shui-Man Kwan, Kwok Pui-lan, André LaCocque, Stephen E. Lahey, John Tsz Pang Lai, Emiel Lamberts, Armando Lampe, Craig Lampe, Beverly J. Lanzetta, Eve LaPlante, Lizette Larson-Miller, Ariel Bybee Laughton, Leonard Lawlor, Bentley Layton, Robin A. Leaver, Karen Lebacqz, Archie Chi Chung Lee, Marilyn J. Legge, Hervé LeGrand, D. L. LeMahieu, Raymond Lemieux, Bill J. Leonard, Ellen M. Leonard, Outi Leppä, Jean Lesaulnier, Nantawan Boonprasat Lewis, Henrietta Leyser, Alexei Lidov, Bernard Lightman, Paul Chang-Ha Lim, Carter Lindberg, Mark R. Lindsay, James R. Linville, James C. Livingston, Ann Loades, David Loades, Jean-Claude Loba-Mkole, Lo Lung Kwong, Wati Longchar, Eleazar López, David W. Lotz, Andrew Louth, Robin W. Lovin, William Luis, Frank D. Macchia, Diarmaid N. J. MacCulloch, Kirk R. MacGregor, Marjory A. MacLean, Donald MacLeod, Tomas S. Maddela, Inge Mager, Laurenti Magesa, David G. Maillu, Fortunato Mallimaci, Philip Mamalakis, Kä Mana, Ukachukwu Chris Manus, Herbert Robinson Marbury, Reuel Norman Marigza, Jacqueline Mariña, Antti Marjanen, Luiz C. L. Marques, Madipoane Masenya (ngwan'a Mphahlele), Caleb J. D. Maskell, Steve Mason, Thomas Massaro, Fernando Matamoros Ponce, András Máté-Tóth, Odair Pedroso Mateus, Dinis Matsolo, Fumitaka Matsuoka, John D'Arcy May, Yelena Mazour-Matusevich, Theodore Mbazumutima, John S. McClure, Christian McConnell, Lee Martin McDonald, Gary B. McGee, Thomas McGowan, Alister E. McGrath, Richard J. McGregor, John A. McGuckin, Maud Burnett McInerney, Elsie Anne McKee, Mary B. McKinley, James F. McMillan, Ernan McMullin, Kathleen E. McVey, M. Douglas Meeks, Monica Jyotsna Melanchthon, Ilie Melniciuc-Puica, Everett Mendoza, Raymond A. Mentzer, William W. Menzies, Ina Merdjanova, Franziska Metzger, Constant J. Mews, Marvin Meyer, Carol Meyers, Vasile Mihoc, Gunner Bjerg Mikkelsen, Maria Inêz de Castro Millen, Clyde Lee Miller, Bonnie J. Miller-McLemore, Alexander Mirkovic, Paul Misner, Nozomu Miyahira, R. W. L. Moberly, Gerald Moede, Aloo Osotsi Mojola, Sunanda Mongia, Rebeca Montemayor, James Moore, Roger E. Moore, Craig E. Morrison O.Carm, Jeffry H. Morrison, Keith Morrison, Wilson J. Moses, Tefetso Henry Mothibe, Mokgethi Motlhabi, Fulata Moyo, Henry Mugabe, Jesse Ndwiga Kanyua Mugambi, Peggy Mulambya-Kabonde, Robert Bruce Mullin, Pamela Mullins Reaves, Saskia Murk Jansen, Heleen L. Murre-Van den Berg, Augustine Musopole, Isaac M. T. Mwase, Philomena Mwaura, Cecilia Nahnfeldt, Anne Nasimiyu Wasike, Carmiña Navia Velasco, Thulani Ndlazi, Alexander Negrov, James B. Nelson, David G. Newcombe, Carol Newsom, Helen J. Nicholson, George W. E. Nickelsburg, Tatyana Nikolskaya, Damayanthi M. A. Niles, Bertil Nilsson, Nyambura Njoroge, Fidelis Nkomazana, Mary Beth Norton, Christian Nottmeier, Sonene Nyawo, Anthère Nzabatsinda, Edward T. Oakes, Gerald O'Collins, Daniel O'Connell, David W. Odell-Scott, Mercy Amba Oduyoye, Kathleen O'Grady, Oyeronke Olajubu, Thomas O'Loughlin, Dennis T. Olson, J. Steven O'Malley, Cephas N. Omenyo, Muriel Orevillo-Montenegro, César Augusto Ornellas Ramos, Agbonkhianmeghe E. Orobator, Kenan B. Osborne, Carolyn Osiek, Javier Otaola Montagne, Douglas F. Ottati, Anna May Say Pa, Irina Paert, Jerry G. Pankhurst, Aristotle Papanikolaou, Samuele F. Pardini, Stefano Parenti, Peter Paris, Sung Bae Park, Cristián G. Parker, Raquel Pastor, Joseph Pathrapankal, Daniel Patte, W. Brown Patterson, Clive Pearson, Keith F. Pecklers, Nancy Cardoso Pereira, David Horace Perkins, Pheme Perkins, Edward N. Peters, Rebecca Todd Peters, Bishop Yeznik Petrossian, Raymond Pfister, Peter C. Phan, Isabel Apawo Phiri, William S. F. Pickering, Derrick G. Pitard, William Elvis Plata, Zlatko Plese, John Plummer, James Newton Poling, Ronald Popivchak, Andrew Porter, Ute Possekel, James M. Powell, Enos Das Pradhan, Devadasan Premnath, Jaime Adrían Prieto Valladares, Anne Primavesi, Randall Prior, María Alicia Puente Lutteroth, Eduardo Guzmão Quadros, Albert Rabil, Laurent William Ramambason, Apolonio M. Ranche, Vololona Randriamanantena Andriamitandrina, Lawrence R. Rast, Paul L. Redditt, Adele Reinhartz, Rolf Rendtorff, Pål Repstad, James N. Rhodes, John K. Riches, Joerg Rieger, Sharon H. Ringe, Sandra Rios, Tyler Roberts, David M. Robinson, James M. Robinson, Joanne Maguire Robinson, Richard A. H. Robinson, Roy R. Robson, Jack B. Rogers, Maria Roginska, Sidney Rooy, Rev. Garnett Roper, Maria José Fontelas Rosado-Nunes, Andrew C. Ross, Stefan Rossbach, François Rossier, John D. Roth, John K. Roth, Phillip Rothwell, Richard E. Rubenstein, Rosemary Radford Ruether, Markku Ruotsila, John E. Rybolt, Risto Saarinen, John Saillant, Juan Sanchez, Wagner Lopes Sanchez, Hugo N. Santos, Gerhard Sauter, Gloria L. Schaab, Sandra M. Schneiders, Quentin J. Schultze, Fernando F. Segovia, Turid Karlsen Seim, Carsten Selch Jensen, Alan P. F. Sell, Frank C. Senn, Kent Davis Sensenig, Damían Setton, Bal Krishna Sharma, Carolyn J. Sharp, Thomas Sheehan, N. Gerald Shenk, Christian Sheppard, Charles Sherlock, Tabona Shoko, Walter B. Shurden, Marguerite Shuster, B. Mark Sietsema, Batara Sihombing, Neil Silberman, Clodomiro Siller, Samuel Silva-Gotay, Heikki Silvet, John K. Simmons, Hagith Sivan, James C. Skedros, Abraham Smith, Ashley A. Smith, Ted A. Smith, Daud Soesilo, Pia Søltoft, Choan-Seng (C. S.) Song, Kathryn Spink, Bryan Spinks, Eric O. Springsted, Nicolas Standaert, Brian Stanley, Glen H. Stassen, Karel Steenbrink, Stephen J. Stein, Andrea Sterk, Gregory E. Sterling, Columba Stewart, Jacques Stewart, Robert B. Stewart, Cynthia Stokes Brown, Ken Stone, Anne Stott, Elizabeth Stuart, Monya Stubbs, Marjorie Hewitt Suchocki, David Kwang-sun Suh, Scott W. Sunquist, Keith Suter, Douglas Sweeney, Charles H. Talbert, Shawqi N. Talia, Elsa Tamez, Joseph B. Tamney, Jonathan Y. Tan, Yak-Hwee Tan, Kathryn Tanner, Feiya Tao, Elizabeth S. Tapia, Aquiline Tarimo, Claire Taylor, Mark Lewis Taylor, Bishop Abba Samuel Wolde Tekestebirhan, Eugene TeSelle, M. Thomas Thangaraj, David R. Thomas, Andrew Thornley, Scott Thumma, Marcelo Timotheo da Costa, George E. “Tink” Tinker, Ola Tjørhom, Karen Jo Torjesen, Iain R. Torrance, Fernando Torres-Londoño, Archbishop Demetrios [Trakatellis], Marit Trelstad, Christine Trevett, Phyllis Trible, Johannes Tromp, Paul Turner, Robert G. Tuttle, Archbishop Desmond Tutu, Peter Tyler, Anders Tyrberg, Justin Ukpong, Javier Ulloa, Camillus Umoh, Kristi Upson-Saia, Martina Urban, Monica Uribe, Elochukwu Eugene Uzukwu, Richard Vaggione, Gabriel Vahanian, Paul Valliere, T. J. Van Bavel, Steven Vanderputten, Peter Van der Veer, Huub Van de Sandt, Louis Van Tongeren, Luke A. Veronis, Noel Villalba, Ramón Vinke, Tim Vivian, David Voas, Elena Volkova, Katharina von Kellenbach, Elina Vuola, Timothy Wadkins, Elaine M. Wainwright, Randi Jones Walker, Dewey D. Wallace, Jerry Walls, Michael J. Walsh, Philip Walters, Janet Walton, Jonathan L. Walton, Wang Xiaochao, Patricia A. Ward, David Harrington Watt, Herold D. Weiss, Laurence L. Welborn, Sharon D. Welch, Timothy Wengert, Traci C. West, Merold Westphal, David Wetherell, Barbara Wheeler, Carolinne White, Jean-Paul Wiest, Frans Wijsen, Terry L. Wilder, Felix Wilfred, Rebecca Wilkin, Daniel H. Williams, D. Newell Williams, Michael A. Williams, Vincent L. Wimbush, Gabriele Winkler, Anders Winroth, Lauri Emílio Wirth, James A. Wiseman, Ebba Witt-Brattström, Teofil Wojciechowski, John Wolffe, Kenman L. Wong, Wong Wai Ching, Linda Woodhead, Wendy M. Wright, Rose Wu, Keith E. Yandell, Gale A. Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- The Cambridge Dictionary of Christianity
- Published online:
- 05 August 2012
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- 20 September 2010, pp xi-xliv
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Clostridium difficile-associated diarrhoea: epidemiological data from Western Australia
- T. V. Riley, G. L. O'Neill, R. A. Bowman, C. L. Golledge
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- Journal:
- Epidemiology & Infection / Volume 113 / Issue 1 / August 1994
- Published online by Cambridge University Press:
- 15 May 2009, pp. 13-20
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The incidence of Clostridium difficile-associated diarrhoea (CDAD) was investigated retrospectively at a 690-bed teaching hospital for the period 1983–92. Our aims were to determine: (i) the distribution by age and sex of patients with CDAD, (ii) the possibility of a seasonal trend and, (iii) the influence of infection control procedures, contamination of the hospital environment and the use of third-generation cephalosporins. The laboratory diagnosis of CDAD was based on demonstration of the organism by stool culture and/or detection of specific cytotoxin in stool filtrates. C. difficile was detected in 917 patients who were being investigated for diarrhoeal illness. Yearly isolations varied from a low of 49 in 1983 to a high of 120 in 1990 (Chi square for linear trend 128·8; P < 0·005). Most patients were elderly, with 63% aged 60 years or more; the majority (59%) were female. The relationship between culture of C. difficile and detection of cytotoxin in faecal extracts was also examined. Sixty percent of a sample of 132 isolates from patients in whom faecal cytotoxin was not detected produced cytotoxin in vitro, suggesting that culture is a more sensitive indicator of infection with C. difficile than cytotoxin detection. When the total number of faecal specimens received in the laboratory was used as a denominator there was an increase in the number of incident cases of CDAD between 1983 and 1990, apart from 1986. When occupied bed days was used as the denominator a similar trend was observed with a peak in 1990. These increases correlated with an increase in the use of third-generation cephalosporins at SCGH between 1983 and 1989 (Pearson's correlation coefficient, 0·90). The introduction of Body Substance Isolation in 1989, in conjunction with other infection control procedures, appears to have halted the rise, despite a continuing use of broad-spectrum cephalosporins. In order to reduce the number of cases of CDAD, either a reduction in levels of environmental contamination or a reduction in the use of third-generation cephalosporins is required. If this can be achieved the economic consequences, in terms of an opportunity cost, will be considerable.
The FMRFamide-like neuropeptide AF2 (Ascaris suum) is present in the free-living nematode, Panagrellus redivivus (Nematoda, Rhabditida)
- A. G. Maule, C. Shaw, J. W. Bowman, D. W. Halton, D. P. Thompson, T. G. Geary, L. Thim
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- Journal:
- Parasitology / Volume 109 / Issue 3 / September 1994
- Published online by Cambridge University Press:
- 06 April 2009, pp. 351-356
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Available primary structural information suggests that the FMRFamide-related peptides (FaRPs) from parasitic and free-living nematodes are different, and that free-living forms may not represent appropriate models for the study of the neurochemistry of parasitic forms in the laboratory. However, here we report the isolation and unequivocal identification of AF2 (originally isolated from the parasite, Ascaris suum) from acidified alcoholic extracts of the free-living species, Panagrellus redivivus. While reverse-phase HPLC analysis of extracts revealed FMRFamide-immunoreactivity to be highly heterogeneous, AF2 was the predominant FMRFamide-immunoreactive peptide present (at least 26 pmol/g wet weight of worms). This peptide was also the major immunoreactant identified by an antiserum raised to the conserved C- terminal hexapeptide amide of mammalian pancreatic polypeptide (PP), which has been used previously to isolate neuropeptide F (NPF). These observations were confirmed by radioimmunoassay and chromatographic fractionation of an acidified alcoholic extract of A. suum heads. The FMRFamide-related peptides present in a nematode extract may be highly dependent on the extraction medium employed, and these data would suggest that this complement of neuropeptides may not be as different between parasitic and free-living nematodes as initial studies have suggested. Finally, all of the evidence suggests that NPF is not present in nematodes and that the PP-immunoreactant previously demonstrated immunochemically is probably AF2.
The structure of a chemically reacting plane mixing layer
- S. M. Masutani, C. T. Bowman
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- Journal of Fluid Mechanics / Volume 172 / November 1986
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- 21 April 2006, pp. 93-126
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Experiments were performed to examine the structure of a chemically reacting, gas-phase, two-stream plane mixing layer. Temporally and spatially resolved measurements of streamwise velocity and of the concentrations of a reactant and product species and a conserved scalar were recorded across the mixing layer at streamwise locations between Redelta; = 730–2520. Non-reacting flow experiments were conducted to establish the entrainment and mixing characteristics of the layer. Reacting flow experiments were performed using dilute concentrations of the reactants, NO and O3, to ensure that the flow field remained isothermal. The probability density functions (p.d.f.s) and associated statistical quantities of the conserved and reactive scalars are compared with results from previous analytical and experimental studies. The data suggest, in concert with the Broadwell-Breidenthal model, that fluid in the mixing layer exists in three states: tongues of unmixed free-stream fluid which, on occasion, stretch across the layer; finite-thickness interfacial diffusion zones of mixed fluid which border the parcels of unmixed fluid; and regions comprising fluid of nearly homogeneous composition. The data also confirm previously reported asymmetry in entrainment rates from the two feed streams and show the important role of molecular diffusion in the mixing process. A fast-chemistry assumption, applied to predict reactive-species concentrations from the measured conserved-scalar p.d.f.s, overestimates the extent of reaction, indicating the importance of finite-rate chemistry for the present conditions. A Damköhler number, based on large-scale mixing times, is shown to be useful in determining the applicability of a fast-chemistry analysis to reacting mixing layers.
An experimental investigation of the effects of compressibility on a turbulent reacting mixing layer
- M. F. MILLER, C. T. BOWMAN, M. G. MUNGAL
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- Journal of Fluid Mechanics / Volume 356 / 10 February 1998
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- 10 February 1998, pp. 25-64
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Experiments were conducted to investigate the effect of compressibility on turbulent reacting mixing layers with moderate heat release. Side- and plan-view visualizations of the reacting mixing layers, which were formed between a high-speed high-temperature vitiated-air stream and a low-speed ambient-temperature hydrogen stream, were obtained using a combined OH/acetone planar laser-induced fluorescence imaging technique. The instantaneous images of OH provide two-dimensional maps of the regions of combustion, and similar images of acetone, which was seeded into the fuel stream, provide maps of the regions of unburned fuel. Two low-compressibility (Mc=0.32, 0.35) reacting mixing layers with differing density ratios and one high-compressibility (Mc=0.70) reacting mixing layer were studied. Higher average acetone signals were measured in the compressible mixing layer than in its low-compressibility counterpart (i.e. same density ratio), indicating a lower entrainment ratio. Additionally, the compressible mixing layer had slightly wider regions of OH and 50% higher OH signals, which was an unexpected result since lowering the entrainment ratio had the opposite effect at low compressibilities. The large-scale structural changes induced by compressibility are believed to be primarily responsible for the difference in the behaviour of the high- and low-compressibility reacting mixing layers. It is proposed that the coexistence of broad regions of OH and high acetone signals is a manifestation of a more biased distribution of mixture compositions in the compressible mixing layer. Other mechanisms through which compressibility can affect the combustion are discussed.
Corinthium aes and black bronze in the early medieval period
- C. Stapleton, S. G. E. Bowman, P. T. Craddock, S. La Niece, S. M. Youngs
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- Journal:
- The Antiquaries Journal / Volume 75 / September 1995
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- 21 April 2011, pp. 383-390
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- September 1995
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Age Disorientation in Schizophrenia: A Constant Prevalence of 25 per cent in a Chronic Mental Hospital Population?
- M. Stevens, T. J. Crow, M. J. Bowman, E. C. Coles
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- The British Journal of Psychiatry / Volume 133 / Issue 2 / August 1978
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- 29 January 2018, pp. 130-136
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- August 1978
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The prevalence of age disorientation was estimated in the population of patients with a diagnosis of schizophrenia in a large mental hospital. Of these 357 patients 25 per cent demonstrated age disorientation, defined as a five-year discrepancy between true and subjective age, and 11 per cent of the population believed themselves to be within five years of the age they were at admission, although they were a mean 28.9 years older. Age-disorientated patients differed from the age-orientated in being significantly older. However, when age-matched, they were younger at first admission and had a longer duration of stay than patients with a diagnosis of schizophrenia without age-disorientation. Age-disorientation may thus be a feature of a type of schizophrenic illness of early onset and poor prognosis.