Browsing by Author "Henning, P A"

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    A massive spiral galaxy in the zone of avoidance
    (Oxford University Press, 2006) Donley, J L; Koribalski, B S; Staveley-Smith, L; Kraan-Korteweg, R C; Schroder, A; Henning, P A
    We report the discovery of a very HI-massive disc galaxy, HIZOAJ0836-43, at a velocity of vhel = 10689kms-1, corresponding to a distance of 148Mpc (assuming H0 = 75kms-1Mpc-1). It was found during the course of a systematic HI survey of the southern Zone of Avoidance (ZOA) (|b| <= 5°) with the multibeam system at the 64-m Parkes radio telescope. Follow-up observations with the Australia Telescope Compact Array reveal an extended HI disc. We derive an HI mass of 7.5 × 1010Msolar. Using the HI radius, we estimate a total dynamical mass of 1.4 × 1012Msolar, similar to the most massive known disc galaxies such as Malin1. HIZOAJ0836-43 lies deep in the ZOA where the optical extinction is very high, AB = 9.8mag. However, in the near-infrared (NIR) wavebands, where the extinction is considerably lower, HIZOAJ0836-43 is clearly detected by both the Deep Near Infrared Survey of the Southern Sky (DENIS) and Two-Micron All-Sky Survey (2MASS). Deep Anglo-Australian Telescope NIR (Ks and H band) images show that HIZOAJ0836-43 is an inclined disc galaxy with a prominent bulge (scalelength 2.5arcsec or 1.7kpc), and an extended disc (scalelength 7arcsec or 4.7kpc) which can be traced along the major axis out to a radius of 20arcsec or 13.4kpc (at 20magarcsec-2 in Ks). The HI disc is much more extended, having a radius of 66kpc at 1Msolarpc-2. Detections in the radio continuum at 1.4GHz and at 60μm (IRAS) are consistent with HIZOAJ0836-43 forming stars at a rate of ~35Msolaryr-1. We compare the properties of HIZOAJ0836-43 with those of the most HI-massive galaxies currently known, UGC4288, UGC1752 and Malin1, all of which are classified as giant low surface brightness galaxies. The observations were obtained with the Australia Telescope which is funded by the Commonwealth of Australia for operations as a National Facility managed by CSIRO.
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    Phototherapy and exchange transfusion for neonatal hyperbilirubinaemia:Neonatal academic hospitals' consensus guidelines for South African hospitals and primary health care facilities
    (2006) Horn, A R; Kirsten, G F; Kroon, S M; Henning, P A; Möller, G; Pieper, C; Adhikari, M; Cooper, P; Hoek, B; Delport, S; Nazo, M; Mawela, B
    The purpose of this document is to address the current lack of consensus regarding the management of hyperbilirubinaemia in neonates in South Africa. If left untreated, severe neonatal hyperbilirubinaemia may cause kernicterus and ultimately death and the severity of neonatal jaundice is often underestimated clinically. However, if phototherapy is instituted timeously and at the correct intensity an exchange transfusion can usually be avoided. The literature describing intervention thresholds for phototherapy and exchange transfusion in both term and preterm infants is therefore reviewed and specific intervention thresholds that can be used throughout South Africa are proposed and presented graphically. A simplified version for use in a primary care setting is also presented. All academic heads of neonatology departments throughout South Africa were consulted in the process of drawing up this document and consensus was achieved.