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The role of the queen in wax secretion and comb building in the Cape honeybee, Aps mellifera capensis (Escholtz)

  • Authors: Whiffler, Lynne Anne
  • Date: 1992
  • Subjects: Honeybee Honey, Comb Beeswax Bee culture -- Queen rearing
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5763 , http://hdl.handle.net/10962/d1005451
  • Description: The role of the queen in wax secretion and comb building was studied in the the Cape honeybee, Apis mellifera capensis (Escholtz). The percentage of bees bearing wax and the amount of wax borne by these bees did not differ between the experiments. This meant that the queenless and queenright colonies had the potential to construct equal amounts of comb as the amounts of wax available for comb building was the same. Contrary to this prediction, queenright colonies constructed 8 times more comb than their queenless counterparts. Queenright Apis mellifera scutellata colonies constructed 4 times more comb than their queenless counterparts. The increased amount of 9-oxo-2-decanoic acid (90DA) in the A.m.capensis mandibular gland secretions could not alone account for this difference. In fact, A.m.capensis and A.m.scutellata colonies constructed similar amounts of comb when they were given their own queens or queens from the other race. Worker bees need to have direct contact with their queen for comb building to be enhanced. Even when the queen had her mandibular glands extirpated and tergite glands occluded large amounts of comb were constructed than when access to the queen was limited. Direct access to the head of a mated queen proved to be the stimulus enhancing comb building. No comb was constructed when the workers had access to the abdomen of the queen. Virgin queens did not stimulate comb building. The relatively large amounts of 90DA and 9HDA from the mandibular glands of Cape virgin queens had not influenced comb building. Worker sized cells were generally constructed. These cells were slightly smaller than those constructed by European honeybees, but were indicative of African bees. A few queen less colonies constructed cells that were of an intermediate drone and worker size. Four mandibular gland pneromones were measured by gas chromatography. No correlations between these pheromones and the comb construction measurements were found. It is unlikely that the mandibular gland pheromones are the only pheromones that stimulate comb building. Pheromones from other glands on the head may contribute towards the enhancement of comb building, and they are not present in virgin queens
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  • Date Issued: 1992

Recruitment of juvenile marine fishes into permanently open and seasonally open estuarine systems on the southern coast of South Africa

  • Authors: Whitfield, Alan K , Kok, H M
  • Date: 1992
  • Subjects: Marine fishes -- Migration -- South Africa , Estuarine fisheries
  • Language: English
  • Type: Text
  • Identifier: vital:15020 , http://hdl.handle.net/10962/d1019801 , ISBN 0-86810-232-6 , Ichthyological Bulletin of the J.L.B. Smith Institute of Ichthyology; No. 57
  • Description: The recruitment of juvenile marine fishes into the Knysna and Swartvlei estuaries was monitored over 30 months using seine, scoop and cast nets. The relative abundance, seasonality and growth of the dominant species are presented, and includes the Cape stumpnose Rhabdosargus holubi, white steenbras Lithognathus lithognathus, blacktail Diplodus sargus, strepie Sarpa salpa, Cape moony Monodactylus falciformis, southern mullet Liza richardsonii, groovy mullet Liza dumerilii, striped mullet Liza tricuspidens, flathead mullet Mugil cephalus, freshwater mullet Myxus capensis and leervis Lichia amia. Information on a further 12 species is also provided. Recruitment of most fish species into the Swartvlei and Knysna estuaries reaches a peak during summer, which coincides with maximum food resource availability and corresponds to the time when systems along this section of the coast are often open to the sea. Artificial winter breaching of the Swartvlei mouth has occurred in the past, and has generally led to the premature closure of the system and loss of the ‘head’ of water needed for the summer opening. This type of mouth manipulation leads to reduced availability of estuarine nursery areas for marine fishes along the southern Cape coast. Comparisons between the recruitment of juvenile fishes into the Knysna and Swartvlei estuaries indicate that higher densities of most species were recorded in the former system. This is attributed mainly to the fact that the Knysna mouth is deep, permanently open, and has a strong marine influence when compared to the shallow, narrow and seasonally closed Swartvlei mouth. However, in a regional context both Knysna and Swartvlei are large, unpolluted systems, which serve as important nursery areas for many species of fish. On this basis alone, these contrasting estuarine systems should be allocated the highest possible conservation status. , Rhodes University Libraries (Digitisation)
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  • Date Issued: 1992

A rhetorical analysis of 1 Timothy 2:9-15 with a special focus on the role of women in the church

  • Authors: Williams, Allan Alexander
  • Date: 1992
  • Subjects: Bible -- Criticism, interpretation, etc. , Women in the Bible , Women in Christianity -- History -- Early church, ca. 30-600 , Women in Christianity , Sexism in religion
  • Language: English
  • Type: Thesis , Masters , MTh
  • Identifier: vital:1299 , http://hdl.handle.net/10962/d1015721
  • Description: This thesis investigates the role of women in the early church as portrayed in 1 Timothy 2:9-15 using the recently-developed method of Rhetorical Analysis. It makes use of a rhetorical approach largely based on the method proposed by Kennedy, supplemented by insights from scholars who have emphasised the argumentative element in rhetoric. This method illustrates how the role of women in the church is decisively determined by the argument in the letter as a whole. A brief survey of classical rhetoric is given. The typical structure of a rhetorical discourse is listed with its component sections. The validity of using rhetorical analysis as a means for interpreting New Testament texts is justified. Textual units are identified from the structure of the text. Rhetorical insights are used to explain how the identified units cohere within the overall structure of the letter and how they relate to one another and interact. The thesis is developed that the section on women and teaching can only be meaningfully investigated in the light of the text as a whole and of the motifs in the letter. The thesis has a special focus on 2:9-15. This section is analysed in more detail than the rest of the text with the exception of 1 Timothy 1. As exordium, the latter provides the introduction to the situation dealt with in the letter, introduces the case, and sets the tone for the rest of the letter. The persuasive power of rhetoric in any situation depends to a large extent on its use of common tradition. The socio-cultural setting of the author is consequently analysed. Finally, the role of women in Graeco-Roman society is analysed in terms of motifs found in 1 Timothy 2:9-15.
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  • Date Issued: 1992

The artificial recharge of urban stormwater runoff in the Atlantis coastal aquifer

  • Authors: Wright, Alan
  • Date: 1992
  • Subjects: Atlantis water resource management scheme , Urban hydrology -- South Africa , Urban runoff -- South Africa , Storm sewers -- South Africa , Water resources development -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4817 , http://hdl.handle.net/10962/d1005491 , Atlantis water resource management scheme , Urban hydrology -- South Africa , Urban runoff -- South Africa , Storm sewers -- South Africa , Water resources development -- South Africa
  • Description: The thesis covers the investigation of the storm water runoff and artificial recharge components of the Atlantis Water Resource Management Scheme in the Southwestern Cape. The objective of the study was to obtain an in-depth knowledge of the process of artificial recharge of urban storm water runoff, in order to identify the most efficient recharge management strategy for the Atlantis aquifer. To achieve the objective it was necessary to first study the existing knowledge on urban storm water hydrology and artificial recharge by spreading, and to create a conceptual model of what might be expected. The study area was then investigated to examine how closely the actual situation was reflected by the conceptual model, enabling recommendations to be made for the sound management of the system. The stormwater runoff component was found to differ from most urban hydrological studies as a result of its large baseflow component. The sandy nature of the catchment, small percentage area of effective impervious surface, and high groundwater table resulted in the baseflow constituting more than 40% of the total storm water runoff and accounting for over 60% of the pollution load. The "first flush" effect established as a major source of pollution in other studies, was found to be of minor significance in this study area. The overall stormwater quality (excluding the noxious industrial baseflow) was found acceptable for artificial recharge within the study area, although the baseflow from the industrial sub-catchments showed the potential for being a major source of pollution in the future. The treated wastewater used for artificial recharge prior to 1987 was found to be unacceptable for recharge purposes. The treated industrial effluent should under no circumstances be recharged up-gradient of the Witzand well field. The treated domestic effluent although of a poorer quality than the resident Witzand well field groundwater could be recharged in order to boost recharge volumes and form a buffer against further intrusion by the poor quality groundwater from the Brakkefontein area. This would however only be acceptable if strict water quality control is maintained and recharge does not take place west of the present basin. The recharge basin was found to be well situated with respect to influencing the Witzand wellfield and maintaining a groundwater buffer against poor quality groundwater flow from the northeast towards the central area of the wellfield. Unfortunately the surrounding low-lying topography and sandy retaining walls have resulted in return flow and raised groundwater-levels. The raised groundwater mound does not comply with the conceptual model and together with the sandy nature of the unsaturated zone resulted in less effective purification during infiltration. The practice of letting large portions of the basin floor dry-out during summer was shown to be beneficial and the periodic cleaning of the deeper portions of the basin essential. The artificially recharged water was found to have influenced the upper portion of the aquifer well beyond the West Coast Road. The study of groundwater quality being a good method for tracing artificially recharged water. The groundwater quality has improved as a result of artificial recharge since the removal of treated wastewater from the recharge basin. The groundwater was (ii) found to be very responsive to the slightest changes in recharge basin water quality or/and quantity. Management of the recharge basin therefore had to be very much of a compromise between qualitative and quantitative approaches. The present approach of recharging all the stormwater runoff throughout the year providing the most efficient compromise under the present conditions. The study revealed that the most efficient recharge management strategy would be the recharge of treated domestic sewage effluent in the present recharge basin and all residential storm water runoff plus industrial "storm flow" stormwater runoff in a new recharge basin located northwest of the present basin. Strict water quality control must be maintained on the water discharged into the basins and an annual wet/dry cycle implemented within the basins to boost infiltration. The entire system should continue being monitored to safe guard the groundwater resource from pollution and over exploitation.
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  • Date Issued: 1992

A letter signed by D B Farrell, 21 March 1992

A.P.A. Chubb's letter to Rhodes Museum Curator, dated 26 April 1992

International Woman of the Year Award

  • Date: 1992 , 2022-10-06
  • Subjects: Bam, Brigalia , Bam, Brigalia -- Awards
  • Language: English
  • Type: award , realia
  • Identifier: http://hdl.handle.net/10948/56925 , vital:57204
  • Description: Dr. Brigalia Bam received the International Woman of the Year award from the International Biographical Centre of Cambridge, England 1991-1992. She received the award for recognition of her services to women’s struggle for recognition. , Donated/gifted to Nelson Mandela University Archives , Forms part of: Brigalia Bam collection
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  • Date Issued: 1992
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