40,754 research outputs found
The construction of Karen Karnak: The multi-author-function
No full textThis thesis is situated within the comparatively recent developments of Web 2.0 and the emergence of interactive WikiMedia, and explores the mode of authorship within a Read/Write culture compared to that of a Read/Only tradition. The hypothesis of this study is that the role of the audience has become merged with the author, and as such, represents new functions and attributes, distinct from a more conventional concept of authorship, in which the roles of audience and author are more separate. Read/Write and participatory culture, as defined by this study, is focused on collaboration, and includes the influences of D.I.Y. culture, Open-Source practices and the production of text by multiple authors. Multi-authorship presents a re-thinking of several concepts which support the notion of the individual author, since the focus of multi-authorship is not on attribution and ownership of a finished text, but on the continued malleability of a text. Modes of multi-authorship, demonstrated in the use of the pseudonyms Alan Smithee and Karen Eliot, represent declarative authors whose names signify multiple origins, whilst concurrently indicating a distinct body of work. The function of these names form an important context to this study, since primary research involves the construction of an experimental mode of multi-authorship utilising WikiMedia technology and the interaction of thirty nine participants, who are invited to create a body of work under the collective pseudonym Karen Karnak. The data generated by this experiment is analysed using aspects of Michel Foucault's author-function to identify and determine power structures inherent in the WikiMedia context. The interplay of power structures, including concepts such as identity, ownership and the body of work, affect the resulting mode of authorship and contribute to the construction of Karen Karnak, suggesting further areas of research into the emerging multi-author
Foreign bodies in a pediatric emergency department in South Africa.
No full textObjectives: Foreign body-related pediatric trauma has a high incidence, but studies with large data sets are rare and typically stem from Western settings. The aim of this study was to identify characteristics of foreign body-related trauma in children treated at our trauma unit in South Africa. Methods: In this retrospective study, we analyzed all foreign body-related trauma admissions from 1991 to 2009. We collected detailed data including age, sex, type of foreign body, injury severity, and anatomical location of the foreign body. Results: We analysed 8149 cases. Marginally more boys (54.9%) than girls were involved. The overall median age was 3 years (interquartile range, 2-6 years); 78.8% were younger than 7 years. The predominant anatomical sites were the respiratory tract and the gastrointestinal tract (39.1%); ears (23.9%); nose (19.4%); and extremities (8.8%). The commonest objects were coins (20.8 %), (parts of) jewelry (9.5%), and food (8.7%). Three quarters (74.5%) of patients presented between 1 and 2 hours afte Conclusions: Preventive parent education programs targeting foreign body-related injury should mainly focus on both sexes younger than 7 years. Parents should be taught to keep small objects out of reach of young children, especially coins, because these most often result in a trauma unit visit
Biological synthesis of gold nanoparticles by Thermus scotoductus SA-01
No full textEnglish: The usual strategy to prepare gold nanoparticles involves the reduction of a gold salt in solution by various reducing agents in the presence of a stabilizer. These particles are mostly spherical with poor monodispersity. An alternative means is to use biological material to mediate particle synthesis. Microorganisms such as fungi have demonstrated the ability to produce nanoparticles of different shapes and sizes extending beyond the scope of chemical means, and the microbial interaction with metals also supply eco-friendly methods for nanoparticle production. It has been hypothesized that the proteins involved in nanoparticle synthesis require a co-factor such as NADH / NADPH, as previous studies have indicated that NADH- and NADPH-dependent enzymes are important factors in the biosynthesis of metal nanoparticles. Thermus scotoductus SA-01, a thermophilic bacterium, isolated from an AngloGold Ashanti mine near Carletonville, Republic of South Africa, was used for purification of a gold(III) reducing and nanoparticle synthesizing protein. This bacterium has the ability to produce gold nanoparticles, and more than one pathway can be followed to produce these particles. A protein was purified to homogeneity by using a combination of several liquid chromatography resins. The N-terminal sequence was obtained by using automated Edman degradation. The protein purified is not a classical oxido-reductase and was identified as an ABC transporter peptide-binding protein (~70kDa). This discovery shows that gold nanoparticles can be produced by proteins other than oxidoreductases. The interaction of the protein extracted and purified from Thermus scotoductus SA-01, as well as the recombinant proteins, with liquid gold under varying physico-chemical conditions have been studied using TEM, EDS, and by measuring the plasmon resonance band, to illustrate the effect on particle morphology and to elucidate the protein mechanism. The size and the shape of particles could, to an extent, be manipulated by controlling the environmental parameters. The purified protein as well as the recombinant proteins was only able to produce nanoparticles in the presence of sodium dithionite and it is thus hypothesized that the donation of electrons via the disulphide bridge in the protein is involved in the reduction of the gold ions. Even though the recombinant proteins had the ability toproduce nanoparticles they were not as efficient as the native protein, but when the optimum parameters for the recombinant proteins are established they could be used in the upscale production of gold nanoparticles or gold nanosheets.Afrikaans: Die algemeenste strategie vir die voorbereiding van nanopartikels behels die reduksie van ʼn
opgeloste goudsout deur verskeie reduseermiddels in die teenwoordigheid van ʼn
stabiliseerder. Hierdie partikels is meestal sferies met lae monodispersiteit. ʼn Alternatiewe
manier om partikels te vorm is om biologiese materiaal te gebruik. Mikroörganismes, soos
fungi, beskik oor die vermoeë om nanopartikels van verskillende vorme en groottes te
produseer, wat ʼn verbetering is op die gebruik van chemiese metodes. Hierdie mikrobiese
interaksie met metale verskaf ook ʼn omgewingsvriendelike metode vir die produksie van
nanopartikels.
Vorige studies het getoon dat NADH- en NAD(P)H- afhanklike ensieme belangrike
faktore is in die biosintese van metaal nanopartikels. Dit het gelei tot die hipotese dat
proteïene wat betrokke is by goud nanopartikel sintese ʼn kofaktor soos NADH / NAH(P)H
benodig.
ʼn Proteïen wat in staat is om goud te reduseer en nanopartikels te vorm, is gesuiwer
vanuit die termofiele bacterium, Thermus scotoductus SA-01. Hierdie bakterium was
geïsoleer vanuit ʼn AngloGold Ashanti myn naby Carletonville, Republiek van Suid-Afrika en
het die vermoeë om goud nanopartikels te produseer deur meer as een biologiese weg te volg.
Die proteïen is gesuiwer deur gebruik te maak van ʼn kombinasie van verskeie vloeistofchromatografie
harse. Die N-terminale proteïen volgorde is verkry deur gebruik te maak van
Edman degradering. Die gesuiwerde proteïen is nie ʼn klasieke oksido-reduktases nie, maar is
geïdentifiseer as ʼn ABC transporter-peptied-bindings proteïen (~70kDa). Hierdie ontdekking
wys dat goud nanopartikels geproduseer kan word deur ander proteïene as oksido-reduktases.
TEM, EDS en die meeting van die plasmon resonans band is gebruik om die effek van
variërende fisiese-chemiese kondisies op partikel morfologie te toon en om die proteïen
meganisme op te klaar. Vir die doel is die gesuiwerde proteïen vanuit Thermus scotoductus
SA-01 asook rekombinante proteïene gebruik.
Die grootte en vorm van die partikels kon tot ʼn mate gemanipuleer word deur
omgewingsfaktore te beheer. Die gesuiwerde proteïen asook die rekombinante proteïene kon
slegs nanopartikels produseer in die teenwoordigheid van natriumdithionaat en ʼn hipotese is geformuleer dat die disulfied brug in die proteïen betrokke is by die reduksie van die goud
ione. Alhoewel die rekombinante proteïene oor die vermoeë beskik om nanopartikels te
produseer is dié nie so effektief soos die gesuiwerde proteïen nie. Indien die optimale
kondisies vir die rekombinante proteïene uitgeklaar word, sal dié waarskynlik in die
grootskaalse produksie van goud nanopartikels of goud nanoplate gebruik kan word
Uberbestuurders : jammer, maar nie werkenemers van Uber SA nie
No full text“Uber” is wyse van vervoer wat wêreldwyd groot afmetings aanneem. Hierdie moderne verskynsel ondermyn gevestigde taxiondernemings in groot stede en regerings wend verskillende maatreëls aan om Uber te reguleer. In Duitsland, Spanje en China is dit byvoorbeeld verbied en in die Verenigde State van Amerika en in Engeland het die howe Uberbestuurders as “werknemers” bestempel. In Suid-Afrika het die Kommissie vir Versoening, Bemiddeling en Arbitrasie hulle aanvanklik as werknemers beskou, maar in Uber South Africa Technology Services (Pty) Ltd v National Union of Public Service and Allied Workers het die Arbeidshof beslis dat hulle nie werknemers van Uber SA is nie. Hierdie bydrae bevraagteken die Arbeidshof se benadering. Uit grondwetlike hoek beskou, moes die hof internasionale regspraak oorweeg het; sou dit sin gemaak het om op die omskrywing van “werkgewer” ingevolge artikel 200B van die Wet op Arbeidsverhoudinge te steun; en moes breër grondwetlike benadering gevolg word deur diensverhoudings van die bestaan van formele kontrak te skei.http://www.lexisnexis.co.zaam2018Mercantile La
1) SA Literature Research / SA Letterkundenavorsing; en 2) Woorde as Dade. Taalhandelinge as Letterkunde
No full textBook Reviews / Boekresensies
SA Literature Research / SA Letterkundenavorsing Charles Malan (red.). 1984 Pretoria: Raad vir Geesteswetenskaplike Navorsing
Woorde as Dade. Taalhandelinge as Letterkunde Van Coller, H.P.; Van Jaarsveld, G.J. (reds.). 1984. Durban: Butterworth
The Tshivenḓa-English Ṱahalusamaipfi/Dictionary as a Product of South African Lexicographic Processes
No full text<p>ABSTRACT: The publication of a dictionary is regarded as the result of a lexicographic process. Three subtypes of a lexicographic process have been noted, namely the primary comprehensive, the secondary comprehensive and the dictionary specific lexicographic processes. In South Africa, the three lexicography processes correspond to the respective mandates of the Pan South African Language Board (PanSALB), the National Lexicography Units (NLUs) and the editorial teams involved in the compilation of the specific dictionaries. This hierarchical arrangement of the lexicographic practice is supported by the government within the country's national multilingual policy which was lauded in linguistic and lexicographic circles as a triumph for cultural democracy. It is almost a decade since these planned lexicographic processes have been in place. It seems the right time to consider the products of these South African lexicographic processes which are envied by many foreign lexicographers, especially in Africa. Accordingly, the article evaluates these lexicographic processes with special reference to the Tshivend√a–English T√halusamaipfi/Dictionary. Specifically, it addresses the question: To what extent does this dictionary represent lexicographic development in the indigenous South African languages which were marginalised before the establishment of the NLUs? A few insights are drawn from modern lexicographic theories for the general improvement of future lexicographic practice in languages with limited lexicographic tools such as Venda.</p><p>OPSOMMING: Die Tshivenda–English Thalusamaipfi / Dictionary as 'n produk van Suid-Afrikaanse leksikografiese prosesse. Die publikasie van 'n woordeboek word beskou as die resultaat van 'n leksikografiese proses. Drie ondersoorte van 'n leksikografiese proses is onderskei, naamlik die primêr omvattende, die sekondêr omvattende en die woordeboek-spesifieke leksikografiese prosesse. In Suid-Afrika stem die drie leksikografiese prosesse ooreen met die onderskeie mandate van die Pan-Suid-Afrikaanse Taalraad (PanSAT), die Nasionale Leksikografie-eenhede (NLE's) en die redaksiespanne betrokke by die samestelling van die bepaalde woordeboeke. Hierdie hiërargiese rangskikking van die leksikografiese praktyk word ondersteun deur die regering binne die land se nasionale veeltalige beleid wat in taalkundige en leksikografiese kringe geloof is as 'n triomf vir kulturele demokrasie. Dit is byna 'n dekade sedert hierdie beplande leksikografiese prosesse in plek is. Dit lyk na die regte tyd om die produkte van hierdie Suid-Afrikaanse leksikografiese prosesse te beskou wat deur baie vreemde leksikograwe, veral in Afrika, beny word. Gevolglik beoordeel die artikel hierdie leksikografiese prosesse met spesiale verwysing na die Tshivenda–English Thalusamaipfi/Dictionary. Dit roer veral die vraag aan: Tot watter mate verteenwoordig hierdie woordeboek leksikografiese ontwikkeling in die inheemse Suid-Afrikaanse tale wat gemarginaliseer is voor die totstandkoming van die NLE's? 'n Aantal insigte word verkry van moderne leksikografiese teorieë vir die algemene verbetering van die toekomstige leksikografiese praktyk in tale met beperkte leksikografiese gereedskap, soos Venda.</p><p>Sleutelwoorde: LEKSIKOGRAFIESE PROSES, LEKSIKOGRAFIESE BEPLANNING, PANSAT, NASIONALE LEKSIKOGRAFIE-EENHEDE, LEKSIKOGRAFIESE PRAKTYK, METALEKSIKOGRAFIE, WOORDEBOEK, TWEETALIGE WOORDEBOEK, MAKROSTRUKTUUR, MIKROSTRUKTUUR</p>
Language Change and SA-OT: The case of sentential negation
No full textSimulated Annealing for Optimality Theory (SA-OT) updates Optimality Theory by adding a model of performance to a theory of linguistic competence. Our aim is to show that SA-OT can contribute to language change simulations. Performance "errors" are considered to be one of the causes of variation and change. We have chosen to model the evolution of sentential negation (SN). The descriptive background adopts Jespersen's Cycle, according to which the evolution of sentential negation follows three main stages (1. pre-verbal, 2. discontinuous, and 3. post-verbal). Therefore, we advance a novel model for SN, based on SA-OT. It reproduces the three pure and the two observed mixed stages, whereas it correctly predicts the lack of an intermediate stage between 3 and 1. The success of the approach corroborates the computational, performance-based approach to the data. Finally, we employ the iterated learning paradigm to reproduce historical changes in a "simulated corpus study". This enterprise turns out to be more difficult than one would naively believe.Appeared open access as: Computational Linguistics in the Netherlands Journal (CLIN), vol. 1 (2011), pp. 21-40, and is available at http://www.clinjournal.org/sites/default/files/Lopopolo.pdfA. Lopopolo and Biró, T., “Language Change and SA-OT. The case of sentential negation”, Computational Linguistics in the Netherlands Journal, vol. 1, pp. 21-40, 2011.Peer Reviewe
Catchment management in semi-arid area of central South Africa: Strategy for improving water productivity
No full textPublished ArticleIn the semi-arid part of central South Africa, population growth and industrial
development are the driving forces for an increased demand for water. This accentuates
the need for wise decisions by catchment management agencies (CMAs), especially
in water scarce semi-arid areas. These decisions become more and more complex
as the range of demands widens over the spectrum of water consumers, i.e.
municipal, industrial, irrigation and rainfed farming. A study was conducted in the
Upper Modder River catchment which is situated in the semi-arid area of central
South Africa, where crop production in the catchment using conventional production
technique is currently not suitable due to marginal and erratic rainfall. Moreover, the
area is characterised by low precipitation use efficiency as a result of large runoff and
evaporation losses on clay and duplex soils. A labour intensive in-field rainwater
harvesting (IRWH) technique recently introduced into a part of the basin occupied
by small scale farmers has been shown to increase maize and sunflower yields by 30
to 50% compared to conventional tillage, making it a feasible option for the these
farmers in the catchment. The area of land suitable for the IRWH located in the
communal land is estimated to be 23 000 ha. Two catchment management options
presented in this paper are: option-1: allowing the IRWH suitable land in the communal farming area to remain under grassland and utilizing the runoff downstream
for irrigating maize; option-2: utilizing the IRWH suitable land for maize production
in the basin, using the IRWH technique. Results showed that the expected maize
production from option-2 was higher than from option-1. A financial analysis also
showed that gross margin, expressed as Rand per m3 of rainwater utilized, was between
0.0234 to 0.0254 under option-1 and 0.0354 for option-2. This clearly shows
that use of rainwater where it falls has high socio-economic benefits for the communal
farmers who are currently struggling to achieve sustainable livelihoods
Abjection in the novels of Marlene Van Niekerk
No full textIncludes bibliographical references.In this thesis, three of Marlene van Niekerk's novels, translated from Afrikaans into English, are examined, with the focus on the representation of abjection in the texts under discussion.The theoretical point of departure of this study is Julia Kristeva's essay Powers of horror (1982), which addresses, in particular, the notion of abjection and how certain abject elements play a pivotal role in people's everyday lives. From a psychoanalytic perspective, abjection is viewed as a revolt against the mother and foregrounds particularly the influence of the maternal body over the subject. In this instance, the subject desires liberation from the hold of the maternal and seeks to subject the mother to abjection. Bodily fluids seeping out of the body, diseases, viruses, dirt and death (and in particular the corpse) are all elements that are encompassed in the concept of abjection. Manifestations of abjection in the form of the abject mother, abject spaces, abject bodies and the link between abjection and filth are comparatively analysed in the three texts. The thesis concludes by showing that Van Niekerk deliberately inscribes elements of the abject into her texts so as to transgress and deconstruct the norms associated with a patriarchal and racist society in South Africa. Van Niekerk also undermines the norms that underpin such a society: religious indoctrination, gender oppression and Othering. By writing her novel Triomf (1999) in a demotic register, Van Niekerk furthermore questions the prevalent assumptions about what is deemed proper language for writing a novel. Writing, for her, thus serves the purposes of abjecting, of rejecting the impositions of the symbolic order. Following the publication of her first collection of short stories, Die Vrou wat haar verkyker vergeet het [The woman who forgot her binoculars] in 1992, there was general consensus that the baroque nature of the language resulted in reader resistance to the text. This explains why she decided to write her first novel in the crude and obscene language of a low-class family, the Benades of Triomf
Up-scaling of rainwater harvesting for crop production in the communal lands of the Modder River basin in South Africa: comparing upstream and downstream scenarios
No full textPublished ArticleThe study area is the Upper and Middle Modder River basin situated in a semi-arid area of central South Africa. This is an important catchment because of the relatively large nearby towns of Bloemfontein, Botshabelo and Thaba Nchu. Crop production in the basin using conventional production techniques is currently not suitable due to marginal and erratic rainfall, and high evaporative demand, as well as low precipitation use efficiency on the clay and duplex soils caused by large runoff and evaporation losses. A labour-intensive in-field rain-water harvesting (IRWH) technique for crop production recently introduced into a part of the basin occupied by communal farmers has been shown to increase maize and sunflower yields by 30 to 50% compared to conventional tillage, making crop production utilising this technique a feasible proposition for these farmers. The area of land suitable for the IRWH in the basin is estimated to be 80 667 ha, of which 15 000 ha is located in the communal land. The two catchment management options compared in this paper are:
• Allowing the 80 667 ha to remain under grassland and utilising the runoff downstream for irrigating maize
• Utilising the 80 667 ha for maize production in the basin using the IRWH technique.
Results showed that the expected maize production from the options shown above were 23 040t and 137 134t respectively. The large unproductive water losses during storage and conveyance to downstream use points are probably the main reason for this large difference in production. An economic analysis, which enabled the grazing benefit to be included in the first option, shows that the gross margin of this option, expressed as R/m3 of rain water utilized, could be expected to be between 0.0234 to 0.0254 under current conditions, of which irrigation contributed about 25% or less. The comparable value for the IRWH option was 0.0354. The second option is clearly shown to be the most preferable, with high socio-economic benefits for the communal farmers who are currently struggling to achieve sustainable livelihoods
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