Articles by Author: R N Porter

Search results for R N Porter

We found 11 results for you
  1. THE BITE OF THE LEECH <em>LIMNATIS FENESTRATA</em> MOORE 1939, IN NATAL

    THE BITE OF THE LEECH <em>LIMNATIS FENESTRATA</em> MOORE 1939, IN NATAL

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa
    The leech Limnatis fenestrata is a hazard to fishermen and limnologists working in the field in Natal. Since nothing is known of the pathogenicity of this leech, its bite and the sequelae following attack by L. fenestrate are described.
  2. NOTE ON BRIDGING THEOREMS FOR SEMISIMPLICIAL SETS

    NOTE ON BRIDGING THEOREMS FOR SEMISIMPLICIAL SETS

    Item type: Journal Article • Journal: Quaestiones Mathematicae
    In this note we present a variant of bridging theorems in abstract homotopy theory which applies to the category of semisimplicial sets yielding bridging theorems for semisimplicial sets which might prove useful in semi-algebraic topology.
  3. Short Notes

    Short Notes

    Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology
  4. On H-closed and U-closed functions

    On H-closed and U-closed functions

    Item type: Journal Article • Journal: Quaestiones Mathematicae
    In this article, we extend the work on H-closed functions started by Cammaroto, Fedorchuk and Porter in 1998. Also, U-closed functions are introduced and characterized in terms of filters and adherence. The hereditary and productivity properties are examined and developed...
  5. Association of the pitch canker pathogen <em>Fusarium circinatum</em> with grass hosts in commercial pine production areas of South Africa

    Association of the pitch canker pathogen <em>Fusarium circinatum</em> with grass hosts in commercial pine production areas of South Africa

    Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science
    The pitch canker pathogen, Fusarium circinatum, has major impacts on production in pine nurseries and plantations in South Africa. Thus far, efforts to reduce local spread have focused on rouging of infected pines and sanitation to eliminate local sources of...
  6. Cardinal functions <em>F</em><sub><em>θ</em></sub>(<em>X</em>) and <em>t</em><sub><em>θ</em></sub>(<em>X</em>) for H-closed spaces

    Cardinal functions <em>F</em><sub><em>θ</em></sub>(<em>X</em>) and <em>t</em><sub><em>θ</em></sub>(<em>X</em>) for H-closed spaces

    Item type: Journal Article • Journal: Quaestiones Mathematicae
    This article extends the results proved by Cammaroto and Kočinac in 1993 by showing that tθ(X) = tθ(Xs) = t(Xs) = Fθ(X) = Fθ(Xs) = F(Xs) for every H-closed and Urysohn space. Examples are developed to study all of the...
  7. Monitoring the recovery of a previously exploited surf-zone fish community in the St Lucia Marine Reserve, South Africa, using a no-take sanctuary area as a benchmark

    Monitoring the recovery of a previously exploited surf-zone fish community in the St Lucia Marine Reserve, South Africa, using a no-take sanctuary area as a benchmark

    Item type: Journal Article • Journal: African Journal of Marine Science
    Limiting accessibility to a fishing area can reduce fishing effort effectively and may therefore promote local recovery of depleted stocks. In January 2002, beach driving was banned in South Africa, thereby reducing angler access to large areas of the coastline,...