Growing of trees in home-gardens by rural households in the Eastern Cape and Limpopo Provinces, South Africa:
- Authors: Shackleton, Charlie M , Paumgarten, Fiona , Cocks, Michelle L
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141360 , vital:37965 , DOI: 10.1080/13504500509469647
- Description: Trees provide a wide range of goods and services to rural households which, when incorporated into their livelihood strategies, help reduce their vulnerability to adversity. Governments and policy makers often ignore the contribution made by trees and consequently resources are focussed on cash crops and livestock. Villagers in the Eastern Cape and Limpopo Province, South Africa utilise a range of trees from home-gardens for various purposes, although predominantly for fruit and shade. Trees are either planted or actively retained in households' home-gardens. There were noticeable differences between the villages in the Eastern Cape and those in Limpopo Province, particularly with respect to the overall density of trees per hectare and the number of species per household, both being significantly greater in Limpopo Province. The five most preferred species were listed for each village, revealing a preference for exotic fruit trees in Limpopo Province and a mix of exotic fruit trees and shade trees in the Eastern Cape. Households also retained useful indigenous species, predominantly fruit-bearing species. A range of factors constrain tree growing in home-gardens and households engage in practices to grow and maintain their trees. Not all of these constraints and practices were significantly different between the various localities.
- Full Text:
- Date Issued: 2009
Mulch tower treatment system Part I: Overall performance in greywater treatment
- Authors: Zuma, Bongumusa M , Tandlich, Roman , Whittington-Jones, Kevin J , Burgess, Jo E
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71537 , vital:29862 , https://doi.org/10.1016/j.desal.2008.03.030
- Description: A mulch tower (MT) system for greywater treatment is introduced in this paper. Materials used to assemble the MT system included mulch, coarse sand, fine and coarse gravel. Limited removal efficiency of the MT system was demonstrated for alkalinity, total hardness, pH, Cl–, PO43–, NH4+, and SO42–, with the estimated cumulative removals ranging from 7 to 12%. Intermediate removal efficiency was observed for chemical oxygen demand (COD), NO3–, and S2– with the estimated cumulative removals ranging from 24 to 28%. The highest removal efficiency was observed for the total suspended solids (TSS) with the estimated cumulative removal equal to 52%. Given the minute residence time in the MT system, the results obtained were promising and justify scale-up studies for potential on-site applications. The MT effluent did not meet hygienic norms with respect to the faecal coliform concentration (FC) and the total coliform concentration (TC), and further effluent treatment is required before any discharge or reuse of the treated greywater. Further research should focus on characterisation of the microbial community of the MT, and the fate of Cl–, PO43–, NH4+, and SO42–.
- Full Text: false
- Date Issued: 2009
Umabatha: Zulu play or Shakespeare translation?
- Authors: Wright, Laurence
- Date: 2009
- Language: English
- Type: text , article
- Identifier: vital:7062 , http://hdl.handle.net/10962/d1007426 , https://www.taylorfrancis.com/books/e/9781351963381/chapters/10.4324%2F9781315264219-12
- Description: preprint , There can be few recent theatrical productions in greater need of interpretative effort than Welcome Msomi’s Umabatha. From its inception debate has raged over the cultural status of the production: was it an authentic expression of Zulu culture, or a tacky piece of ‘blacksploitation’? – to use Russell Vandenbroucke’s term. Was the production pleasing evidence of Shakespeare’s universality, a gift to the colonies returning joyfully to the motherland with interest accruing? Could it perhaps be a case of Zulu culture triumphing over Shakespeare, native invention swamping and overwhelming a colonially-imposed ‘high culture’? Was the show performing ‘Africa’ for the world and, if so, was this the way Africa ought to be represented in the twentieth century? Or were we perhaps looking at a fetishized theatrical commodity, wrenched from any authentic cultural roots, and circulating aimlessly but profitably through a globalised theatrical cosmopolis? Such speculative questions – and there are many others – have regularly jostled each other in the bulky heritage of Umabatha’s reception history. The central problem underlying this chapter is whether it might not be possible to define a basis for a more objective response to some of them, so that the issues involved no longer rest quite so slackly in the realm of mere critical opinion.
- Full Text:
- Date Issued: 2009
A global study of forensically significant calliphorids: implications for identification
- Authors: Harvey, M L , Gaudieri, S , Villet, Martin H , Dadour, I R
- Date: 2008
- Language: English
- Type: text , Article
- Identifier: vital:6863 , http://hdl.handle.net/10962/d1011156
- Description: A proliferation of molecular studies of the forensically significant Calliphoridae in the last decade has seen molecule-based identification of immature and damaged specimens become a routine complement to traditional morphological identification as a preliminary to the accurate estimation of post-mortem intervals (PMI), which depends on the use of species-specific developmental data. Published molecular studies have tended to focus on generating data for geographically localised communities of species of importance, which has limited the consideration of intraspecific variation in species of global distribution. This study used phylogenetic analysis to assess the species status of 27 forensically important calliphorid species based on 1167 base pairs of the COI gene of 119 specimens from 22 countries, and confirmed the utility of the COI gene in identifying most species. The species Lucilia cuprina, Chrysomya megacephala, Ch. saffranea, Ch. albifrontalis and Calliphora stygia were unable to be monophyletically resolved based on these data. Identification of phylogenetically young species will require a faster-evolving molecular marker, but most species could be unambiguously characterised by sampling relatively few conspecific individuals if they were from distant localities. Intraspecific geographical variation was observed within Ch. rufifacies and L. cuprina, and is discussed with reference to unrecognised species.
- Full Text:
- Date Issued: 2008
Beneficial effects of medicinal plants in fish diseases
- Authors: Stratev, Deyan , Zhelyazkov, Georgi , Noundou, Xavier Siwe , Krause, Rui W M
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123487 , vital:35447 , https://doi.org/10.1007/s10499-017-0219-x
- Description: Fish are constantly in contact with pathogens inhabiting water. High population density as well as poor hydrodynamic conditions and feeding lead to an increased sensitivity towards infections. In order to prevent major economic losses due to diseases, various medications are used for treatment and prevention of infections. The use of antimicrobial drugs in aquacultures could lead to emergence of resistance in pathogenic microorganisms. Alternatives are being sought over the last few years to replace antibiotics, and medicinal plants are one of available options for this purpose. These plants are rich in secondary metabolites and phytochemical compounds, which have an effect against viral, bacterial, and parasitic diseases in fish. Their main advantage is their natural origin and most of these plants do not represent threat for human health, the fish, and the environment. The goal of this review is to present information on the treatment of viral, bacterial, and parasitic diseases in fish through medicinal plants, with focus on the mechanisms of action of the identified secondary metabolites, fractions, or plant extracts.
- Full Text:
- Date Issued: 2008
Industrial relations in Namibia since independence: between neo-liberalism and neo-corporatism?
- Authors: Klerck, Gilton
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6320 , http://hdl.handle.net/10962/d1011314
- Description: The paper seeks to examine the changes and continuities in industrial relations in post-independence Namibia. In particular, it aims to explore some of the key elements in the process through which the distribution of the costs and rewards of economic and industrial restructuring is institutionalised. The paper concentrates, through in-depth interviews with key role players, on how the attempts at sustaining a durable and redistributive trade-off between economic efficiency and social equality led to a contradictory fusion of neo-liberal and neo-corporatist forms of labour market regulation. The research reveals that changes in the regulation of the labour market since independence have created opportunities for advancement and participation by groups of more skilled and organised employees, while weaker and less skilled groups have generally experienced a decline in employment conditions and the absence of collective representation. These developments reflect and reproduce patterns of racial and gender discrimination, industrial structure, trade union membership and collective bargaining across the various sectors and occupations. The paper shows that a system of low-skill, low-wage and low-trust relations - with an emphasis on cost reduction and employment "flexibility" - is fast becoming embedded in industrial relations in Namibia. Given the prevailing economic policies, industrial strategies and labour market structures, Namibia's integration into the global economy will most likely involve the increasing dislocation and exclusion of vulnerable and "peripheral" workers from the formal economy. The paper highlights the ways in which the transformation of industrial relations in Namibia is shaped by the legacy of apartheid-colonialism and the pressures of globalisation. Specifically, the conjunction of increasingly deregulated product markets and increasingly regulated labour markets has driven a wedge between the pursuit of short-term objectives and the attainment of long-term transformational goals.
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- Date Issued: 2008
Marginalisation and demographic change in the semi-arid Karoo, South Africa
- Authors: Nel, Etienne L , Hill, Trevor R
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6719 , http://hdl.handle.net/10962/d1006792
- Description: Semi-arid areas are often considered to be environmentally and economically marginal, a situation which has been exacerbated by economic change, shifts in agricultural production and land use, and changing state policy. These themes are explored with reference to a semi-arid landscape, namely the Karoo, which covers some 40% of the geographic space of South Africa and is used primarily for extensive livestock farming. Despite long-term decline in agricultural output, the traditional mainstay of the region, and weakening small town economies, the Karoo's population and the economies of its largest service centres are growing. There are, real socio-economic needs and development backlogs, and the situation has been exacerbated by recent political marginalisation. In this study, the small towns of the region are focal points of investigation and provide a lens to investigate the changing demographic and economic dynamics of the Karoo. Most of the region's population lives in these centres which are service, collection, and distribution points for what traditionally has been an agriculture-based regional economy. This paper explores the concept of marginalisation with specific reference to historical, economic, and demographic change.
- Full Text:
- Date Issued: 2008
Rock magnetic stratigraphy of a mafic layered sill: a key to the Karoo volcanics plumbing system
- Authors: Maes, S M , Ferré, E E , Tikoff, B , Brown, P E , Marsh, Julian S
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144901 , vital:38389 , https://doi.org/10.1016/j.jvolgeores.2005.07.038
- Description: The Insizwa sill is an 1 km-thick subhorizontal layered mafic intrusion and part of the Karoo Large Igneous Province in South Africa. This well-exposed intrusion consists of several superimposed petrologically and geochemically distinct units. Magnetic methods were used to study the intrusion in order to constrain the physical processes active in these types of bodies during crystallization. Rock magnetism studies indicate that within different petrologic units bulk susceptibility is controlled by primary magnetite (with minor pyrrhotite) and/or paramagnetic minerals (olivine, pyroxene). New magnetic data based on 659 specimens obtained from 3 vertical borehole cores, each spaced 5 km apart, confirm the prominent vertical zonation in low field magnetic susceptibility (Klf), degree of anisotropy (Pj) and orientation of the anisotropy of magnetic susceptibility (AMS) axes.
- Full Text:
- Date Issued: 2008
School principals' perceptions of team management : a multiple case-study of secondary schools
- Authors: Van der Mescht, Hennie , Tyala, Zakunzima
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6105 , http://hdl.handle.net/10962/d1009732
- Description: The notion of school management through teams (team management), though not a new phenomenon in South Africa, was formalized after the advent of democracy in 1994 and the subsequent reorganization of the education system. The concept was subsequently fleshed out in official documentation where the composition and roles of school management teams (SMTs) were elaborated upon. The notion of team management is rooted in theories that stress participation, notably site-based (school-based) management, teamwork, and distributed leadership. We report on a study in which the perceptions of secondary school principals, in Grahamstown, South Africa, of team management were explored. The study was interpretive in orientation, and utilized qualitative data gathering techniques in all (ten) of the state-aided secondary schools in Grahamstown in the Eastern Cape province. We found that, while team management was generally welcomed and even celebrated by principals, there were fundamental tensions surrounding principals' understanding of their leadership roles in a team context. We consider the implications of these findings for leadership development in the context of team management.
- Full Text:
- Date Issued: 2008
Tracing and erasure in Kathryn Smith's Psychogeographies: the washing away of wrongs
- Authors: de Jager, Maureen
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147413 , vital:38634 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC31057
- Description: Kathryn Smith's Psychogeographies: The Washing Away of Wrongs is a series of twelve prints comprising photographs and handwritten text, wherein she records her 'pilgrimage' to the former homes of British serial killer Dennis Nilsen. As such, it utilises photographic and autographic traces to 'track' the elusive traces left by Nilsen. Given the lapse of two decades between Nilsen's arrest and Smith's visit, the traces of Nilsen's 'wrongs' seem all but erased by the banal façade of suburban living which has continued on, regardless. In taking this as a starting point, the following article considers the motif of absence that characterises Smith's work as intrinsic to traces per se.
- Full Text:
- Date Issued: 2008
New Unity Movement Bulletin
- Date: 2007-04
- Subjects: Government, Resistance to -- South Africa , South Africa -- History -- 20th century , South Africa -- Politics and government
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10948/31726 , vital:31740 , Bulk File 7
- Description: The Bulletin was the official newsletter of the New Unity Movement. It was published about twice a year and contained articles reflecting the organisation's views on resistance to the Apartheid government.
- Full Text: false
- Date Issued: 2007-04
Enabling and constraining ICT practice in secondary schools: case studies in South Africa
- Authors: Hodgkinson-Williams, Cheryl , Siebörger, Ingrid , Terzoli, Alfredo
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428923 , vital:72546 , https://www.inderscienceonline.com/doi/epdf/10.1504/IJKL.2007.015551
- Description: The use of Information Communication Technology (ICT) in education is being seen as a way of widening access to education, particularly in developing countries. This paper addresses the issue of ICT implemen-tation in secondary schools and focuses specifically on the practices that enable or constrain the successful implementation of ICT for teach-ing and learning activities. It reflects upon the lessons learned from a collective case study undertaken in 12 of the 13 secondary schools in Grahamstown in the Eastern Cape in South Africa. School principals and designated IT teachers were interviewed and on-site infrastructure audits conducted. This paper identifies a number of key enabling and constraining factors surrounding practical issues, including sufficient hardware, appropriate software and affordable connectivity, sufficient technical support and training, policy-related issues such as the role of national, provincial and school policy, the vital contribution of principal leadership and champion teachers as well as ongoing teacher profes-sional development coupled with a willingness to change.
- Full Text:
- Date Issued: 2007
Enlarged arguments in Bantu : evidence from Chichewa
- Authors: Simango, Silvester Ron
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6140 , http://hdl.handle.net/10962/d1011592
- Description: This paper re-examines two types of constructions that have featured in the discussion of possessor ascension in Bantu: one type – an applicative construction – is associated with alienable possession, and the other – non-applicative – is associated with inalienable possession. The study shows that the former expresses affectedness, and that the possessor reading arises only by construal; whereas the latter expresses a part–whole relationship. The paper argues that the two constructions differ in more significant ways than has previously been acknowledged; and that their distinct derivations cannot be captured by traditional possessor ascension (PA) analyses. The putative “alienable” possessor constructions belong to the class of (benefactive) applicative constructions and should be analyzed as such. The paper proposes that the so-called “inalienable” possessor constructions can best be accounted for by positing the existence of “enlarged arguments” wherein the possessum functions as a nominal predicate which more narrowly pinpoints the locus of the action described by the verb.
- Full Text:
- Date Issued: 2007
Lessons from the dead masters: Wordsworth and Byron in J. M. Coetzee's Disgrace
- Authors: Beard, Margot
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6114 , http://hdl.handle.net/10962/d1003827
- Description: As one whose research interests lie in the field of Romanticism, most specifically Wordsworth and Byron, I was obviously intrigued by J. M. Coetzee's use of these poets in Disgrace. Subsequent readings of the work have convinced me that more attention needs to be paid to the deeper implications of their presence in the text. Certainly many scholars have explored the significance of David Lurie's professional interest in the Romantic poets and the novel's imbeddedness in what Jane Taylor has referred to as "the European Enlightenment's legacy of the autonomy of the individual" as well as a specifically "eighteenth century model of philosophical sympathy" (1999, 25). Yet I feel that insufficient attention has been paid to the significance of Romanticism, the Wordsworthian and the Byronic in the novel. Generally, the commentary ranges from seeing Lurie's academic interests as symptomatic of his white colonialist mentality to a more nuanced but insufficiently developed focus on the possibilities lying behind Coetzee's startling juxtaposition of two of the most famed and yet most overtly antagonistic of the Romantic poets. Zoë Wicomb is representative of the first approach. In her estimation, Lurie may be rejected since he "looks to Europe as the centre of reference" and "our feelings and experiences of nature need not be structured by poetic discourses from the metropolis".
- Full Text:
- Date Issued: 2007
Signatures of seaway closures and founder dispersal in the phylogeny of a circumglobally distributed seahorse lineage
- Authors: Teske, Peter R , Hamilton, Healy , Matthee, Conrad A , Barker, Nigel P
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6549 , http://hdl.handle.net/10962/d1006005
- Description: The importance of vicariance events on the establishment of phylogeographic patterns in the marine environment is well documented, and generally accepted as an important cause of cladogenesis. Founder dispersal (i.e. long-distance dispersal followed by founder effect speciation) is also frequently invoked as a cause of genetic divergence among lineages, but its role has long been challenged by vicariance biogeographers. Founder dispersal is likely to be common in species that colonize remote habitats by means of rafting (e.g. seahorses), as long-distance dispersal events are likely to be rare and subsequent additional recruitment from the source habitat is unlikely. In the present study, the relative importance of vicariance and founder dispersal as causes of cladogenesis in a circumglobally distributed seahorse lineage was investigated using molecular dating. A phylogeny was reconstructed using sequence data from mitochondrial and nuclear markers, and the well-documented closure of the Central American seaway was used as a primary calibration point to test whether other bifurcations in the phylogeny could also have been the result of vicariance events. The feasibility of three other vicariance events was explored: a) the closure of the Indonesian Seaway, resulting in sister lineages associated with the Indian Ocean and West Pacific, respectively; b) the closure of the Tethyan Seaway, resulting in sister lineages associated with the Indo-Pacific and Atlantic Ocean, respectively, and c) continental break-up during the Mesozoic followed by spreading of the Atlantic Ocean, resulting in pairs of lineages with amphi-Atlantic distribution patterns.
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- Date Issued: 2007
Stratigraphic correlation of the Awahab and Tafelberg Formations, Etendeka Group, Namibia, and location of an eruptive site for flood basalt volcanism
- Authors: Marsh, Julian S , Milner, Simon C
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6738 , http://hdl.handle.net/10962/d1007552 , http://dx.doi.org/10.1016/j.jafrearsci.2007.04.004
- Description: Detailed field and geochemical investigations in the vicinity of the type section of the Tafelberg Formation of the early Cretaceous Etendeka Group, NW Namibia, have revealed the existence of a large eruptive vent in the lower part of the regional volcanic sequence produced by Strombolian and Vulcanian eruptions. The vent is filled with the thick, differentiated, ponded Kudu-Run olivine-rich basaltic flow, which has a distinctive low Zr/Y geochemical signature as well as a Tafelberg-type tabular basalt and the Nil Desperandum latite. Field evidence indicates that the Kudu-Run basalt and the latite were erupted from fissures located within the vent. Associated with the vent is an extensive pyroclastic apron extending from the vent edge and which is interbedded with the regional stratigraphy. Blocks of Precambrain basement lithologies occur within this deposit and indicate that the vent was excavated to a depth of at least 350 m below the palaeosurface at that time. The original Tafelberg Formation type section described by Erlank et al. [Erlank, A.J., Marsh, J.S., Duncan, A.R., Miller, R.McG., Hawkesworth, C.H., Betton, P.J., Rex, D.C. 1984. Geochemistry and petrogenesis of the Etendeka volcanic rocks from SWA/Namibia, 195–247. In: Erlank, A.J. (Ed.), Petrogenesis of Volcanic Rocks of the Karoo province. Special Publication of the Geological Society of South Africa, vol. 13, 395 p.] the Tafelberg Gully section, crosses from the lower part of the regional sequence into the intra-vent sequence and returns to the regional sequence higher up. In doing so it includes some of the localized intra-vent flows and excludes a number of flows which are part of the regional sequence in its lower part, thus rendering it inappropriate as a type section. A revised type section for the Tafelberg Formation is described by combining the upper part of the Tafelberg Gully section with a new section of 14 flows at the base of the regional sequence in the Tafelberg North (TBN) section some 2 km N of the Tafeleberg Gully. Distinctive flows in the TBN section can be mapped southwards where their precise stratigraphic relationship to the northward-thinning Springbok and Goboboseb Quarts Latite members of the Awahab Formation can be demonstrated. These stratigraphic relationships are entirely consistent with palaeomagnetic reversal stratigraphy and demonstrate that the same N–R–N polarity sequence occurs in the type sections of the Awahab and Tafelberg formations. Thus, the Awahab and Tafelberg magma systems were contemporaneous but the Tafelberg system outlived that of the Awahab. The Awahab system was built from eruptive centres located S of the Huab River whereas the Tafelberg vents were located further north. , Full text article access in Journal of African Earth Sciences, 48 (5). pp. 329-340. Available: http://dx.doi.org/10.1016/j.jafrearsci.2007.04.004
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- Date Issued: 2007
The effect of sulfide on -glucosidases: implications for starch degradation in anaerobic bioreactors
- Authors: Wutor, V C , Togo, C A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6463 , http://hdl.handle.net/10962/d1005792 , dx.doi.org/10.1016/j.chemosphere.2006.03.011
- Description: Membrane associated α-glucosidase activity was investigated in a methanogenic bioreactor (MR) and a biosulfidogenic bioreactor (SR). Temperature and pH optima studies showed temperature optima of 50 °C and pH optima of 8.0 for the α-glucosidases from both the MR and SR. Sulfide (at a concentration of 150 mg l[superscript (−1)]) resulted in the complete loss of all α-glucosidase activity in both the MR and SR. β-Glucosidase activities in our bioreactors were previously shown to be stimulated in the presence of sulfide. α-Glucosidases, in contrast, are inhibited by sulfide. This differential effect of sulfide on α-glucosidase and β-glucosidase activities is highlighted and is of crucial consequence to the respective degradation and utilization of starch and cellulose substrates in natural anaerobic environments and anaerobic bioreactors specifically designed for the accelerated digestion of wastewater sludge under biosulfidogenic conditions.
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- Date Issued: 2007
The humanities, vocationalism and the public good: exploring 'the Hamlet factor'
- Authors: Wright, Laurence
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:7028 , http://hdl.handle.net/10962/d1007214 , https://doi.org/10.1080/17535360712331393503
- Description: preprint , This paper argues that the social mission of the humanities is no longer well understood by the public, sometimes not even by the very institutions seeking to attract students to these disciplines, the universities. It becomes difficult to argue for the cogency of research in the humanities, let alone for a specific national research agenda, when the general relation between the humanities and society is widely mistaken. To address such misapprehensions, the discussion outlines as clearly as possible the characteristic procedures of the humanities, the manner in which they inform individual and social transformation, and the contemporary predicament which makes them more rather than less needed in society’s repertoire of educational resources. With this understanding in place, the paper then puts forward suggestions for strengthening research in the humanities as part of a broader programme to renovate the humanities in the South African education system.
- Full Text:
- Date Issued: 2007
Time-resolved luminescence of low sensitivity quartz from crystalline rocks
- Authors: Chithambo, Makaiko L , Preusser, F , Ramseyer, K , Ogundare, F O
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:6801 , http://hdl.handle.net/10962/d1004164 , https://doi.org/10.1016/j.radmeas.2006.07.005
- Description: preprint , Time-resolved luminescence spectra of low sensitivity natural quartz from crystalline rocks are presented. The luminescence was pulse-stimulated at width using 470 nm blue light from quartz separated from plutonic, metamorphic, volcanic and hydrothermal samples. Measurements were made at 20 °C. All samples show evidence of a short lifetime component less than long although in several cases too weak in intensity to be evaluated accurately. On the other hand, the value of the principal lifetime component varies considerably being about in metamorphic quartz, in plutonic quartz, and in one example of hydrothermal quartz. The results illustrate a new feature of luminescence from quartz for which lifetimes less than or greater than have never been reported at room temperature before. It is argued that the thermal provenance of the quartz and so the annealing it will have experienced influences the size of the observed lifetime. In particular, the results are explained in terms of a model consisting of three luminescence centers with the dominant lifetime linked to preferential recombination at one center depending on the thermal history of the sample and hence the hole concentration of the center.
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- Date Issued: 2007
Indigenous languages and the media in South Africa:
- Authors: Kaschula, Russell H
- Date: 2006
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175137 , vital:42546 , https://hdl.handle.net/10520/EJC15168
- Description: This article explores the status of South Africa’s indigenous languages and how they are being used in the media. More specifically, the performance of these languages in the print media, the broadcasting media and the Internet, is outlined. This is done against the backdrop of the South African Constitution, Section 6, which entrenches eleven official languages. Contrary to the Constitution’s provisions, it is found that the indigenous languages are achieving varying levels of success within the media. The reasons for this are outlined. Finally, the effects of globalisation on the indigenous languages within the media are assessed.
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- Date Issued: 2006