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Dose response and kinetic analysis of thermoluminescence of Li–Zn fluoroborate glass

  • Authors: Thomas, Sunil , Chithambo, Makaiko L
  • Date: 2017
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/116164 , vital:34326 , https://doi.org/10.1080/10420150.2017.1313844
  • Description: The intention of this study is to explore the thermoluminescence properties of beta-irradiated Li–Zn fluoroborate glass. The glow-curve corresponding to 10 Gy shows two peaks when measured at 1°C/s. The dose response of the glass to beta irradiation was investigated. The trapping level parameters such as activation energy, frequency factor and order of kinetics associated with the observed glow-peak were determined using different methods. The thermoluminescence is affected by thermal quenching. A possible mechanism for the thermoluminescence is described.
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  • Date Issued: 2017

Reconfiguring the Omweso board game: performing narratives of Buganda material culture

  • Authors: Kirumira, Rose Namubiru
  • Date: 2019
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/145996 , vital:38487 , https://0-doi.org.wam.seals.ac.za/10.1162/afar_a_00460
  • Description: My artwork titled Nakulabye, which is 4 meters long and weighs 440 pounds, is an intimidating sculptural replica of the Omweso game board (Fig. 1). The wooden sculpture, twenty times larger than an average Omweso game board, includes four cane stools to sit on during play. Its composition is derived from a human face, and it has thirty-two pits (8 × 4) in the configuration of a mancala board. This sculpture was inspired by my engagement with a group of men that I visited in July 2016 in Nakulabye, a town in an urban area of Kampala City, Uganda. At the Nakulabye Omweso Club, a shop veranda in Nakulabye Town, these men play Omweso and chat against the backdrop of a small television that mostly screens British Premiere Leagues. Observing their exchanges, which seem to be informed by moves on the Omweso board and reveal strong, clearly gendered power dynamics, I became curious about the performative place of Omweso as a cultural artifact of the Baganda people.
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  • Date Issued: 2019

The Educational Journal

Activated carbon from lignocellulosic waste residues: effect of activating agent on porosity characteristics and use as adsorbents for organic species

  • Authors: Olorundare, O F , Okonkwo, J O , Msagati, T A M , Mamba, Bhekie B , Krause, Rui W M
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/125233 , vital:35748 , https://doi.org/10.1007/s11270-014-1876-2
  • Description: This paper reports on the effect of activating agents such as the impregnation ratio of phosphoric acid (1:1–1:5) at constant activation temperature on the performance of porous activated carbon from waste residues (maize tassel). The variation in the impregnation ratio of the produced activated carbon (AC) from 1:1 to 1:5 enabled the preparation of a high surface area (1,263 m2/g) and a large pore volume (1.592 cm3/g) of AC produced from maize tassel (MT) using a convectional chemical activating agent (phosphoric acid). Impregnation ratios (IR) of the precursors were varied between 1:1 and 1:5 in which it was found that the ratio of 1:4 was optimal based on the high surface area, while 1:5 has the optimal pore volume value for the produced activated carbon.
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  • Date Issued: 2014

The use and appreciation of urban green spaces: the case of selected botanical gardens in South Africa

  • Authors: Ward, Catherine D , Parker, Caitlin M , Shackleton, Charlie M
  • Date: 2010
  • Language: English
  • Type: Article
  • Identifier: vital:6662 , http://hdl.handle.net/10962/d1007086
  • Description: There are few formal studies on the contribution of botanical gardens as urban green spaces, particularly within developing countries. Therefore, this paper reports on an assessment of the use and appreciation of botanical gardens as urban green spaces in South Africa. Users and staff were surveyed in six national botanical gardens. The gardens provided numerous benefits in terms of conservation, education and recreation. However, the people using the gardens were not demographically representative of the general population of the surrounding city or town. Generally, most of the visitors were middle- to old-aged, well-educated professionals with medium to high incomes. Most were white and English was their home language. There was an even gender representation. Most visited only a few times per year. The majority of users visited the gardens for recreation and psychological reasons rather than educational ones. However, the staff of each garden placed emphasis on education in the gardens and amongst surrounding schools. Most visitors appreciated the conservation dimensions of botanical gardens, and felt that there was insufficient public green space in their town or city. Understanding how people perceive and use the botanical gardens of South Africa is important to inform future research and strategies regarding the conservation of urban green space within a developing country.
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  • Date Issued: 2010

Mapping GPS-derived ionospheric Total Electron Content over Southern Africa during different epochs of solar cycle 23

  • Authors: Moeketsi, D M , Combrinck, W L , McKinnell, Lee-Anne , Fedrizz, M
  • Date: 2007
  • Language: English
  • Type: Article
  • Identifier: vital:6802 , http://hdl.handle.net/10962/d1004165
  • Description: The Southern African Development Community and the International Global Navigation Satellite Systems Service (GNSS) network of dual frequency Global Positioning System (GPS) receivers provide an opportunity to determine Total Electron Content (TEC) over Southern Africa by taking advantage of the dispersive nature of the ionospheric medium. For this task, the University of New Brunswick (UNB) ionospheric modelling technique which applies a spatial linear approximation of the vertical TEC above each station using stochastic parameters in Kalman filter estimation, primed with data from the Southern Africa GPS network, was used for mapping TEC at South African locations during selected days and hours of different epochs of solar cycle 23. Significant enhancements in the TEC value and features, which could be associated with frequent solar events, are evident around a day of extreme solar maximum. These observations are discussed and further investigated by analyzing the GOES 8 and 10 satellites X-ray flux (0.1–0.8 nm) and SOHO Solar EUV Monitor (26.0–34.0 nm) higher resolution data. Comparison of these physical quantities reveals that for each X-ray flare observed, there is an associated EUV flare event. The latter phenomenon causes photoionisation in the daytime ionosphere which results in significant TEC enhancement. The daytime UNB TEC compared with the International Reference Ionosphere (IRI) 2001 predicted TEC found both models to show a good agreement.
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  • Date Issued: 2007

Ectomycorrhizas in association with Pinus patula in Sabie, South Africa

  • Authors: Hawley, Greer L , Taylor, A F S , Dames, Joanna F
  • Date: 2008
  • Language: English
  • Type: Article
  • Identifier: vital:6475 , http://hdl.handle.net/10962/d1006163 , http://www.scielo.org.za/scielo.php?pid=S0038-23532008000400011&script=sci_arttext
  • Description: Forestry is an economically important industry in South Africa,involving extensive exotic plantations of Eucalyptus, Pinus and Acacia species. These tree species have fungal associations, such as ectomycorrhizas, that have become locally naturalized. The forestry industry is increasingly faced with problems of long-term sustainability, increasing soil acidity and depletion of soil nutrients. It is, therefore, essential that the fundamental importance of the ectomycorrhizal (ECM) symbioses in the nutrient cycling, growth, health and survival of these tree species should not be ignored. Research on the species diversity of ECM fungi associated with forestry plant species has been hampered by the difficulty of identifying the fungi involved in the symbiosis. This investigation focused on the ECM fungi associated with Pinus patula (Schlecht. et Cham.) grown in managed plantations in the Sabie region, Mpumalanga province, South Africa. ECM roots were morphotyped and DNA was extracted. The internal transcribed spacer (ITS) region was amplified using the ITS 1F and ITS 4 primers. The sequences were BLASTed using the GenBank and UNITE databases. Twenty-seven extractions were successfully amplified representing 17 different morphotypes. Of the 27 sequences, 21 were identified as ECM fungi and, from the BLAST results, eleven different ECM species could be identified. Selected ECM root types were morphologically and anatomically described according to root morphology, mantle structure, specialized hyphae and rhizomorph arrangement. Seven dominant field types were described and identified as two Amanita species, Scleroderma citrinum, a suilloid species, Thelephora terrestris, a tometelloid species and one resembled an Albatrellus species.
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  • Date Issued: 2008

Recruiters Guidelines

  • Authors: COSATU
  • Date: 2001
  • Subjects: COSATU
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/137210 , vital:37498
  • Description: The purpose of this booklet is to touch in number of areas, which are important at this point for the recruitment campaign of the federation. It is not meant even by implication to provide details of how to handle the campaign what it does is to highlight issues and areas that we must think in the preparation for this campaign. More importantly is the fact that COSATU remains the biggest federation in South Africa and fastest growing international. Beside a loss of membership from + 2 million to + 1.8 million members. The decrease in membership is mostly because of retrenchments. The well known fact is that only about 40% of the workforce that is unionized. The aim of the recruitment drive is to access this 60% that is not unionized. The mistake must not be committed to think that the 40%, which is unionized, belong to COSATU. There are two other federations plus number of non-affiliated unions. Our commitment to One Country One Federation does not stop us to recruit from other unions as long as we remain under different bodies. This October campaign coincides with Red October campaign of the SACP and Health and Safety month of the federation this must be seen as strength than lack of co-ordination. One area that is link to recruitment is the servicing of membership. It is useless to recruit and fail to service membership because every campaign that we will take around recruitment we may find ourselves had to fight with disgruntled members and obviously it will be difficult to attract new members. This must say to us that members come first.
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  • Date Issued: 2001

Topsoil transfer from natural renosterveld to degraded old fields facilitates native vegetation recovery:

  • Authors: Ruwanza, Sheunesu
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/148639 , vital:38758 , https://doi.org/10.3390/su12093833
  • Description: The transfer of soils from intact vegetation communities to degraded ecosystems is seen as a promising restoration tool aimed at facilitating vegetation recovery. This study examined how topsoil transfer from intact renosterveld to degraded old fields improves vegetation diversity, cover, and composition. Transferred topsoil were overlaid on 30 quadrats, each measuring 1 m2, in May 2009. Eight years following the initial soil transfer, vegetation diversity in the soil transfer site showed an increase towards the natural site compared to the old field site where no soil transfer was administered. Both species richness and cover for trees and shrubs in the soil transfer site increased towards the natural site, though this was not the case for herbs and grasses. One-way analysis of similarity (ANOSIM) showed significant (R = 0.55) separation in community composition between sites. The study concludes that soil transfer from intact renosterveld to degraded old fields is a promising restoration technique because it increases species diversity and cover and facilitates vegetation recovery. A significant restoration implication of this study is that soil transfer introduces key renosterveld native tree and shrub species that can facilitate successful restoration and act as restoration foci or nurse plants.
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  • Date Issued: 2020

Human harvesting impacts on managed areas: ecological effects of socially-compatible shellfish reserves

  • Authors: Aswani, Shankar , Flores, Carola F , Broitman, Bernardo R
  • Date: 2015
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/124664 , vital:35644 , https://doi.10.1007/s11160-014-9376-4
  • Description: We examined how human harvesting impacts on managed areas affect the abundance and size distribution of the edible mangrove shellfish Anadara granosa and Polymesoda spp. in the Roviana Lagoon, Solomon Islands. We tested two hypotheses: (1) in areas permanently and temporally closed to human exploitation, abundance and size distribution of these shellfish species is significantly greater than in sites open to exploitation and (2) moderate human disturbance of shell beds, particularly of Polymesoda spp., increases their abundance. Firstly, we studied perceptions of environmental states and processes coupled to foraging and management interventions to assess sociocultural influences on harvesting practices and ascertain the types of management regime that people would consider in a context where poaching and interloping are common practices. Secondly, we compared shellfish abundance and shell size from areas that were permanently protected, temporally reserved for communal harvest, and permanently open for exploitation. Thirdly, drawing from women’s local knowledge, we measured the abundance of Polymesoda spp. in relation to mud compactness in quadrats across the three management regimes. Results showed that both species were significantly more abundant in permanent and temporally closed sites than in open sites. In the mud compactness study, however, while shell abundance was greater in moderately compacted quadrats, there was no statistical relationship between mud compactness and shell abundance within or across the three management regimes. Results suggest that even under the strong impacts of poaching, temporally closed areas have more clams than open areas and are as effective as areas that are permanently closed nominally. The results also suggest that human harvesting regimes can influence the effectiveness of local management decisions and thus are important when designing community-based conservation programs in the Solomon Islands and other Pacific Islands.
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  • Date Issued: 2015

The role of higher education in society: valuing higher education

  • Authors: Badat, Saleem
  • Date: 2009
  • Language: English
  • Type: Conference paper , text
  • Identifier: vital:7122 , http://hdl.handle.net/10962/d1006571
  • Description: From the introduction: Arthur E. Levine, President of the Teachers College of Columbia University, writes that "In the early years of the Industrial Revolution, the Yale Report of 1828 asked whether the needs of a changing society required either major or minor changes in higher education. The report concluded that it had asked the wrong question. The right question was, What is the purpose of higher education?" Levine goes on to add that questions related to higher education “have their deepest roots in that fundamental question” and that “faced with a society in motion, we must not only ask that question again, but must actively pursue answers, if our colleges and universities are to retain their vitality in a dramatically different world”. I propose to speak about three issues: the first is about our changing world; the second is about the three purposes of higher education; the third is about what I consider to be the five key roles of higher education. Finally, I want to conclude by making some observations on the sometimes unrealistic expectations of higher education. , HERS‐SA Academy 2009, University of Cape Town Graduate School of Business, Waterfront, Cape Town, 14 September 2009. Stagnant universities are expensive and ineffectual monuments to a status quo which is more likely to be a status quo ante, yesterday’s world preserved in aspic (Ralf Dahrendorf, 2000:106‐7)
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  • Date Issued: 2009

The Educational Journal

The Educational Journal

Notes on South African gobies possessing free upper pectoral fin rays (Pisces--Gobiidae)

  • Authors: Winterbottom, Richard, 1944- , Rhodes University. J.L.B. Smith Institute of Ichthyology
  • Date: 1976-04
  • Subjects: Bathygobius fuscus , Bathygobius niger , Gobius saldanha , Monishia william , Fishes -- South Africa
  • Language: English
  • Type: text , book
  • Identifier: http://hdl.handle.net/10962/69792 , vital:29580 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
  • Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 16 , This paper arose out of difficulties in identifying collections of gobies whose upper pectoral fin rays are silklike and partially or predominantly free of membrane. Four such species have been recorded from South Africa, but there has been considerable confusion over their identification . Various unreported characters were found useful in separating the species. Certain problems exist in separating J.L.B. Smith's type specimens from the general collection. He invariably separated one specimen (labelled as "type") which was stored in a special type cupboard. This occurred whether or not a holotype was actually designated in the original description. Thus, particularly in his earlier works where no holotype was designated, these specimens (for new species based on more than one specimen) are nomenclatorally syntypes. I will refer to such "type" specimens as "syntype (= putative lectotype)". The remaining specimens (either the rest of the syntypic series or, later, the paratypes) were returned to the general collection. Owing to space limitations, all specimens of the same species were, where possible, kept in a single large jar. Paper tags were sewn on to the specimens, giving locality and date of collection. These tags have an unfortunate tendency to disintegrate. Subsequent separation of syntypes and paratypes is, therefore, subject to error. Since in a syntypic series I am referring to a "putative lectotype", the remainder of such series will be called "syntypes (= putative paralectotypes)".
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  • Date Issued: 1976-04

The Educational Journal

Film production incentives, employment transformation and domestic expenditure in South Africa: visualizing subsidy effectiveness

  • Authors: Collins, Alan , Ishizaka, Alessio , Snowball, Jeanette D
  • Date: 2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/67456 , vital:29094 , https://doi.org/10.1080/10286632.2016.1255206
  • Description: Publisher version , In 2004 the South African Department of Trade and Industry (DTI) introduced a Film and Television Production Rebate Programme. In order to qualify for the rebate, certain criteria have to be met including success in job creation and skills development within the industry, alongside a particular focus on the percentage of ‘historically disadvantaged individuals’ employed. This study sets out the issues associated with evaluating success in meeting these various criteria and is, to the best of our knowledge, the first study to apply multi-criteria visualization techniques to inform the evaluation of public subsidy effectiveness. The ‘PROMETHEE’ method is applied and apart from presenting project performance in a visually intuitive manner, the approach helps to clarify patterns of relative success, show where policy objectives are competing, and to identify project exemplars for more efficiently guiding future public support in the sector.
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  • Date Issued: 2016

Cryptic variation in an ecological indicator organism: mitochondrial and nuclear DNA sequence data confirm distinct lineages of Baetis harrisoni Barnard (Ephemeroptera: Baetidae) in southern Africa

  • Authors: Pereira-da-Conceicoa, L L , Price, Benjamin W , Barber-James, Helen M
  • Date: 2012
  • Language: English
  • Type: text , Article
  • Identifier: vital:7151 , http://hdl.handle.net/10962/d1011855
  • Description: Baetis harrisoni Barnard is a mayfly frequently encountered in river studies across Africa, but the external morphological features used for identifying nymphs have been observed to vary subtly between different geographic locations. It has been associated with a wide range of ecological conditions, including pH extremes of pH 2.9–10.0 in polluted waters. We present a molecular study of the genetic variation within B. harrisoni across 21 rivers in its distribution range in southern Africa.
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  • Date Issued: 2012

The nature of geometry instruction and observed learning-outcomes opportunities in Nigerian and South African high schools:

  • Authors: Atebe, Humphrey U , Schäfer, Marc
  • Date: 2013
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/140919 , vital:37929 , DOI: 10.1080/10288457.2011.10740712
  • Description: The purpose of this qualitative case study involving six secondary school teachers was to obtain insight into how geometry is taught in selected Nigerian and South African high schools. It also aimed, by making use of the van Hiele model of geometry instruction, to elucidate what possible learning opportunities observed instructional methods could offer learners in the subject. The sample comprised three mathematics teachers from Nigeria and three mathematics teachers from South Africa, all of whom were selected using purposive sampling techniques. Instructional activities in six geometry classrooms were recorded on videotape. The van Hiele learning phases provided the framework for data analysis. The findings of this study indicate that observed teaching methods in geometry classrooms in the participating schools offer learners scant opportunity to learn geometry.
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  • Date Issued: 2013

Reclaiming syndicalism: from Spain to South Africa to Global Labour Today

  • Authors: van der Walt, Lucien
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/144824 , vital:38382 , DOI: 10.15173/glj.v5i2.1153
  • Description: Union politics remain central to the new century. It remains central because of the ongoing importance of unions as mass movements, internationally, and because unions, like other popular movements, are confronted with the very real challenge of articulating an alternative, transformative vision. There is much to be learned from the historic and current tradition of anarcho-and revolutionary syndicalism.
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  • Date Issued: 2014

The Educational Journal

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