An examination of feedback on draft essays, using Halliday's definition of context:
- Authors: Quinn, Lynn
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/69500 , vital:29544 , https://doi.org/10.1080/10286632.2016.1255206
- Description: An historical structural understanding underpins the research reported on in this paper. The ideas of the systemic functional linguist, Michael Halliday, are used to examine a draftingresponding-redrafting process used to develop students'. academic writing in the English Language for Academic Purposes (ELAP) course at Rhodes University. Using the Hallidayan framework, I examine how the process can help students adapt to the broader culture of the university and at a more micro level how the comments made by the respondent can help student writers to acquire the academic literacy required to write essays in the context of situation of the ELAP course. The features of field, tenor and mode and their associated textual meanings (that is, experiential meaning, interpersonal meaning and textual meaning) are used to categorise the ways in which comments made at the draft stage of the writing process can develop students' writing. As a result of my research I argue in this paper that it might be useful for writing consultants/lecturers to think of their feedback to students' writing in terms of these categories and to consider whether they have helped students to develop their writing by taking into account the features of the particular social context in which the writing takes place.
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An intercultural approach to implementing multilingualism at Rhodes University, South Africa
- Authors: Kaschula, Russell H , Maseko, Pamela , Dalvit, Lorenzo , Mapi, Thandeka , Nelani, Linda , Nosilela, Bulelwa , Sam, Msindisi S
- Date: 2009
- Subjects: Multilingualism -- South Africa , Intercultural communication , Education, Higher -- South Africa , Language and culture -- South Africa , Language and education -- South Africa , Rhodes University
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59390 , vital:27579 , doi: 10.5842/39-0-74
- Description: The work of intercultural communication theorists such as Ting-Toomey (1999) and Gudykunst (2003) has informed curriculum design and teaching methodology of the courses developed for teaching isiXhosa for vocational purposes to second language (L2) learners. This seems to be an appropriate theoretical paradigm within multilingual South Africa, where intercultural communication is becoming a daily reality for a growing portion of the population. We make use of this theory to introduce and develop experiential understanding of multilingualism at Rhodes University in various departments and, more generally, on campus.
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Evaluating the IRI topside model for the South African region: An overview of the modelling techniques
- Authors: Sibanda, Patrick , McKinnell, Lee-Anne
- Date: 2009
- Language: English
- Type: text , Article
- Identifier: vital:6810 , http://hdl.handle.net/10962/d1004303
- Description: The representation of the topside ionosphere (the region above the F2 peak) is critical because of the limited experimental data available. Over the years, a wide range of models have been developed in an effort to represent the behaviour and the shape of the electron density (Ne) profile of the topside ionosphere. Various studies have been centred around calculating the vertical scale height (VSH) and have included (a) obtaining VSH from Global Positioning System (GPS) derived total electron content (TEC), (b) calculating the VSH from ground-based ionosonde measurements, (c) using topside sounder vertical Ne profiles to obtain the VSH. One or a combination of the topside profilers (Chapman function, exponential function, sech-squared (Epstein) function, and/or parabolic function) is then used to reconstruct the topside Ne profile. The different approaches and the modelling techniques are discussed with a view to identifying the most adequate approach to apply to the South African region’s topside modelling efforts. The IRI-2001 topside model is evaluated based on how well it reproduces measured topside profiles over the South African region. This study is a first step in the process of developing a South African topside ionosphere model.
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Investigating the effect of Genetic Algorithms on Filter Optimisation Within Fast Packet Classifiers
- Authors: Nottingham, Alastair , Irwin, Barry V W
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428674 , vital:72528 , https://www.researchgate.net/profile/Marijke-Coet-zee/publication/220803190_A_Framework_for_Web_Services_Security_Policy_Negotiation/links/0fcfd50f7d806aafc8000000/A-Framework-for-Web-Services-Security-Policy-Negotiation.pdf#page=119
- Description: Packet demultiplexing and analysis is a core concern for network secu-rity, and has hence inspired numerous optimisation attempts since their conception in early packet demultiplexing filters such as CSPF and BPF. These optimisations have generally, but not exclusively, focused on improving the speed of packet classification. Despite these im-provements however, packet filters require further optimisation in order to be effectively applied within next generation networks. One identified optimisation is that of reducing the average path length of the global filter by selecting an optimum filter permutation. Since redundant code generation does not change the order of computation, the initial filter order before filter optimisation affects the average path length of the resultant control-flow graph, thus selection of an optimum permutation of filters could provide significant performance improvements. Unfortu-nately, this problem is NP-Complete. In this paper, we consider using Genetic Algorithms to’breed’an optimum filter permutation prior to re-dundant code elimination. Specifically, we aim to evaluate the effec-tiveness of such an optimisation in reducing filter control flow graphs.
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Recent progress in electrochemical oxidation of saccharides at gold and copper electrodes in alkaline solutions
- Authors: Torto, N
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6599 , http://hdl.handle.net/10962/d1004348
- Description: This article reviews the progress made in the past 10 years, on electrochemical oxidation of saccharides in alkaline media for gold and copper electrodes. The mechanism and processes associated with the electrochemical oxidation of saccharides at native and surface coated electrodes continues to be of great interest. Despite the effort and various mechanisms proposed, still the need for an electrochemically active material that understands the complexity associated with saccharides continues to increase as their detection poses a challenge for bioanalytical chemistry and liquid chromatography.
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Reform in defence of sovereignty: South Africa in the UN Security Council, 2007–2008
- Authors: Bischoff, Paul, 1954-
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/161431 , vital:40626 , https://0-doi.org.wam.seals.ac.za/10.1177/000203970904400205
- Description: After 1994, South Africa became the sine qua non of an internationalist state, willing to promote cooperation amongst a plurality of actors, believing common interests to be more important than their differences. This raised the hopes of constitutionalists, and those who believed in the expansion of a liberal democratic peace. South Africa has acted out two seemingly contradictory roles: those of a reformer and those of a conserver. By 2007–2008 she had shifted towards the latter, conservative-reformist position. Thus, South Africa's voting record at the General Assembly expressed her overriding concern to regionalise African issues and minimise the US and the West shaping political events. This brought her foreign policy into sharper relief. But while in some sense successful, it came at a price: a controversy about her surrendering her internationalism and principles on human rights for African unity and traditional sovereignty. But it also marked the arrival of South Africa in the world of international Realpolitik.
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A preliminary survey of the estuaries on the south coast of South Africa, Cape St Blaize, Mossel Bay - Robberg Peninsula, Plettenberg Bay, with particular reference to the fish fauna
- Authors: James, Nicola C , Harrison, T D
- Date: 2008
- Language: English
- Type: text , Article
- Identifier: vital:7141 , http://hdl.handle.net/10962/d1011834
- Description: The coastal river systems on the south coast of South Africa from Cape St Blaize to Robberg Peninsula were surveyed during October and November 1994. The ichthyofaunal and physico-chemical characteristics of each system are presented and their suitability as estuarine nursery areas is discussed. Five systems (Rooi, Meul, Grooteiland, Kranshoek and Crooks) are outlets of small coastal streams and probably provide little or no habitat for either resident estuarine or migrant marine fishes owing to their small size. Four systems (Maalgate, Gwaing, Skaapkop and Kaaimans) are located within deeply incised valleys and have a permanent connection with the sea. The amount of marginal and intertidal habitat available to fishes, however, is limited due to their morphology. Six systems (Hartenbos, Groot Brak, Touw, Swartvlei, Goukamma and Noetsie) are intermittently open to the sea. Although the Touw and Swartvlei are connected to coastal lake systems, flow within these estuaries is not sufficient to prevent the build up of a sand barrier at the mouth. The Hartenbos, Groot Brak, Goukamma, and Noetsie are also periodically closed by a sand bar. The construction of a dam in the lower catchment of the Groot Brak has affected the hydrology of the system. The two remaining estuaries (Klein Brak and Knysna) are permanently open. In addition to strong tidal currents, the fixing of the mouth of the Knysna Estuary between rocky headlands also serves to maintain a permanent connection with the sea. Mugilidae and Sparidae were represented by the greatest number of species, and also dominated catches numerically and by mass. The fish fauna of all the estuaries surveyed were dominated by the juveniles of estuarine-dependent marine species and estuarine-resident species were also well represented in catches. The estuaries surveyed provide a vital habitat for both marine migrant species and resident species, most of which are endemic to the region.
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Global diversity of mayflies (Ephemeroptera, Insecta) in freshwater
- Authors: Barber-James, Helen M , Gattolliat, J-L , Sartori, Michel , Hubbard, Michael D
- Date: 2008
- Language: English
- Type: text , Article
- Identifier: vital:6895 , http://hdl.handle.net/10962/d1011655
- Description: The extant global Ephemeroptera fauna is represented by over 3,000 described species in 42 families and more than 400 genera. The highest generic diversity occurs in the Neotropics, with a correspondingly high species diversity, while the Palaearctic has the lowest generic diversity, but a high species diversity. Such distribution patterns may relate to how long evolutionary processes have been carrying on in isolation in a bioregion. Over an extended period, there may be extinction of species, but evolution of more genera. Dramatic extinction events such as the K-T mass extinction have affected current mayfly diversity and distribution. Climatic history plays an important role in the rate of speciation in an area, with regions which have been climatically stable over long periods having fewer species per genus, when compared to regions subjected to climatic stresses, such as glaciation. A total of 13 families are endemic to specific bioregions, with eight among them being monospecific. Most of these have restricted distributions which may be the result of them being the relict of a previously more diverse, but presently almost completely extinct family, or may be the consequence of vicariance events, resulting from evolution due to long-term isolation.
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Impediments to the delivery of socioeconomic rights in South Africa
- Authors: Roodt, Monty J
- Date: 2008
- Language: English
- Type: Conference paper
- Identifier: vital:6318 , http://hdl.handle.net/10962/d1011315
- Description: [from the Introduction] The purpose of including Second and Third Generation (STG) rights in a constitution is to provide guidelines to lawmakers to formulate policy and to enable the courts to intervene where these policies are not being implemented satisfactorily. In theory these rights allow citizens to demand from the state access to basic needs, such as adequate land, housing, education, health care, nutrition, and social security. However, this inclusion of rights in the constitution often does not translate into action. The first reason for this is that Second and Third Generation rights may clash with First Generation rights. For example the right to private property may, and in South Africa does, contradict the need for land for the majority. The major problem is whether the policies flowing out of Second and Third Generation rights are pursued with enough vigour by governments, the private sector, primary groups and individuals to overcome this contradiction. In many countries in the world it is the poorest sections of the population, and as Mamdani (1996) pointed out, migrant non-citizens, that bear the brunt of administrative and bureaucratic bungling and neglect.
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The Cultural Use of the Wild Olive Tree by the amaXhosa People in the Eastern Cape Province of South Africa:
- Authors: Cocks, Michelle L , Dold, Anthony P
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141314 , vital:37961 , DOI: 10.1558/jsrnc.v2i3.292
- Description: The cultural meanings of harvested plants have for the most part been ignored in academic research on non-timber forest products (NTFPs) in southern Africa. Historically scientists have tended to ignore the complex relationships between nature and culture. Given the country's unique political and economic past and the current search for sustainable use of natural resources, a focus on the convergence of natural science and cultural diversity is important at this time. Empirical data on cultural practices is being collected in order to develop fresh and relevant insights into the complex relationships between culture and bítKÜversity. The purpose of this paper is to demonstrate that the concept of culture needs to be brought into our understanding of the role of NTFPs. We dtxrument the use and value of a specific tree, Olea europaea L. subsp. africana (Mill.) P,S. Green, called Umiicjuma in the Xhosa language, for cultural purposes, by both rural and urban households.
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The Late Glacial and Holocene avifauna of the island of St Helena, South Atlantic Ocean
- Authors: Lewis, Colin A
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6702 , http://hdl.handle.net/10962/d1006738
- Description: Bird bones from unconsolidated sediments provide a record of the changing avifauna of St Helena from the Late Glacial, at ~ 14000BP, until the present. Changes in avifauna apparently reflect climatic and associated ecological conditions, as well as the effects of human occupation since the island was discovered in 1502. Introduced mammals decimated birds in the seventeenth century and seven endemic species are now extinct, while seven other species are locally extinct. At least nine species that now breed on St Helena have been introduced anthropogenically to the island since it was discovered. The failure to find evidence of native songbirds in the former woodlands of the interior of the island deserves explanation.
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Development of a regional GPS-based ionospheric TEC model for South Africa
- Authors: Opperman, Ben D L , Cilliers, Pierre J , McKinnell, Lee-Anne , Haggard, Raymond
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6799 , http://hdl.handle.net/10962/d1003925
- Description: Advances in South African space physics research and related disciplines require better spatial and time resolution ionospheric information than was previously possible with the existing ionosonde network. A GPS-based, variable degree adjusted spherical harmonic (ASHA) model was developed for near real-time regional ionospheric total electron content (TEC) mapping over South Africa. Slant TEC values along oblique GPS signal paths are quantified from a network of GPS receivers and converted to vertical TEC by means of the single layer mapping function. The ASHA model coefficients and GPS differential biases are estimated from vertical TEC at the ionospheric pierce points and used to interpolate TEC at any location within the region of interest. Diurnal TEC variations with one minute time resolution and time-varying 2D regional TEC maps are constructed. In order to validate the ASHA method, simulations with an IRI ionosphere were performed, while the ASHA results from actual data were compared with two independent GPS-based methodologies and measured ionosonde data.
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Global diversity of mayflies (Ephemeroptera, Insecta) in freshwater
- Authors: Barber-James, Helen M , Gattolliat, Jean-Luc , Sartori, Michel , Hubbard, Michael D
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:7002 , http://hdl.handle.net/10962/d1008361
- Description: The extant global Ephemeroptera fauna is represented by over 3,000 described species in 42 families and more than 400 genera. The highest generic diversity occurs in the Neotropics, with a correspondingly high species diversity, while the Palaearctic has the lowest generic diversity, but a high species diversity. Such distribution patterns may relate to how long evolutionary processes have been carrying on in isolation in a bioregion. Over an extended period, there may be extinction of species, but evolution of more genera. Dramatic extinction events such as the K-T mass extinction have affected current mayfly diversity and distribution. Climatic history plays an important role in the rate of speciation in an area, with regions which have been climatically stable over long periods having fewer species per genus, when compared to regions subjected to climatic stresses, such as glaciation. A total of 13 families are endemic to specific bioregions, with eight among them being monospecific. Most of these have restricted distributions which may be the result of them being the relict of a previously more diverse, but presently almost completely extinct family, or may be the consequence of vicariance events, resulting from evolution due to long-term isolation.
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Inetvis: a graphical aid for the detection and visualisation of network scans
- Authors: Irwin, Barry V W , van Riel, Jean-Pierre
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430381 , vital:72687 , https://www.cs.ru.ac.za/research/g02V2468/publications/Irwin-VizSEC2007_draft.pdf
- Description: This paper presents an investigative analysis of network scans and scan detection algorithms. Visualisation is employed to review network telescope traffic and identify incidents of scan activity. Some of the identified phenomena appear to be novel forms of host discovery. The scan detection algorithms of Snort and Bro are critiqued by comparing the visualised scans with alert output. Where human assessment disa-grees with the alert output, explanations are sought after by analysing the detection algorithms. The algorithms of the Snort and Bro intrusion detection systems are based on counting unique connection attempts to destination addresses and ports. For Snort, notable false positive and false negative cases result due to a grossly oversimplified method of counting unique destination addresses and ports.
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Olive Schreiner in Rhodesia: an episode in a biography
- Authors: Walters, Paul S , Fogg, W Jeremy M
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6123 , http://hdl.handle.net/10962/d1004707
- Description: Readers of biographies of Olive Schreiner - except for the pioneering work of Vera Buchanan-Gould (see 1948, 198-99) - could be forgiven for doubting whether Olive Schreiner ever was in Rhodesia. Although her husband's edition of her Letters includes three which cover this journey (Cronwright-Schreiner 1924a), he makes no mention of it in his Life (1924), and it is not touched on either in First and Scott (1980) or in Stanley's impressive biographical chapter (2002). Arguably, it does nothing to alter the by now well-established outlines of Olive Schreiner's life; yet, as we shall see, the visit itself might have meant the premature end of that life. Moreover, it documents Schreiner's visit to two sites of immense importance to her : the 'Hanging Tree' in Bulawayo which features in the (deliberately shocking) photographic frontispiece to the first edition of Trooper Peter Halket of Mashonaland (1897), and, secondly, Cecil Rhodes's grave in the Matopos. In just over a decade (13 Aug. 1921), she too would lie in her chosen mountaintop tomb.
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Pretopological and topological lattice-valued convergence spaces
- Authors: Jäger, Gunter
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6827 , http://hdl.handle.net/10962/d1012337
- Description: We show that the classical axiom which characterizes pretopological convergence spaces splits into two axioms in the general Heyting algebra-valued case. Furthermore we present a generalization of Kowalski’s diagonal condition to the lattice-valued case.
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Resistance or tolerance: an examination of aphid (Sitobion yakini) phloem feeding on Betta and Betta-Dn wheat (Triticum aestivum)
- Authors: De Wet, L R , Botha, Christiaan E J
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6517 , http://hdl.handle.net/10962/d1005945
- Description: Engineering pest resistance into crops is important. However, the mechanisms of resistance are not clearly understood. In this study, we examined the effects of aphid feeding on Russian wheat aphid-resistant and -susceptible cultivars of wheat (Triticum aestivum L.); Betta-Dn and Betta, respectively, by the grass aphid, Sitobion yakini (Eastop). These cultivars were grown with or without aphid colonies. In each case, we examined the plants specifically for the formation of wound callose associated with the phloem, using aniline blue and fluorescence microscopy. We observed that aphid feeding stimulated the formation of wound callose in the susceptible cultivar, but that callose was comparatively reduced in the resistant cultivar of wheat. In a separate series of experiments, the xenobiotic, 5, 6-carboxyfluorescein diacetate was applied to attached sink leaves, distal to feeding aphids. When leaf segments were examined four hours after application, little evidence of phloem transport of the fluorescent cleavage product, 5, 6-carboxyfluorescein (5, 6-CF), was evident below known aphid-probed sieve tubes. Low levels or absence of 5, 6-CF indicates that either the aphids have successfully redirected sap to themselves, or that the phloem is no longer functional. In contrast, 5, 6-CF transport was evident below sites of aphid probing in Betta-Dn, suggesting that the phloem was still capable of long-distance transport. In addition, callose deposition was reduced in Betta-Dn leaf phloem and it is surmised that transport was not as affected by aphid feeding in the resistant cultivar. This indicates that the ‘resistant’ wheat cultivar may in fact be tolerant to aphid feeding by successfully overcoming the nutrient drain that feeding aphids imposed on the phloem transport system.
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The structural and functional diversity of Hsp70 proteins from Plasmodium falciparum
- Authors: Shonhai, Addmore , Boshoff, Aileen , Blatch, Gregory L
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6486 , http://hdl.handle.net/10962/d1006269 , http://dx.doi.org/10.1110/ps.072918107
- Description: It is becoming increasingly apparent that heat shock proteins play an important role in the survival of Plasmodium falciparum against temperature changes associated with its passage from the cold-blooded mosquito vector to the warm-blooded human host. Interest in understanding the possible role of P. falciparum Hsp70s in the life cycle of the parasite has led to the identification of six HSP70 genes. Although most research attention has focused primarily on one of the cytosolic Hsp70s (PfHsp70-1) and its endoplasmic reticulum homolog (PfHsp70-2), further functional insights could be inferred from the structural motifs exhibited by the rest of the Hsp70 family members of P. falciparum. There is increasing evidence that suggests that PfHsp70-1 could play an important role in the life cycle of P. falciparum both as a chaperone and immunogen. In addition, P. falciparum Hsp70s and Hsp40 partners are implicated in the intracellular and extracellular trafficking of proteins. This review summarizes data emerging from studies on the chaperone role of P. falciparum Hsp70s, taking advantage of inferences gleaned from their structures and information on their cellular localization. The possible associations between P. falciparum Hsp70s with their cochaperone partners as well as other chaperones and proteins are discussed.
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Destined to come to blows?: race and constructions of “rational-intellectual” masculinity ten years after apartheid
- Authors: Vincent, Louise
- Date: 2006
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141619 , vital:37990 , DOI: 10.1177/1097184X05277694
- Description: In 1994, a democratic government came to power in South Africa for the first time in the country's history. But political transition is never a single event or moment. Rather, it is a continuous process that faces setbacks and contradictions. One of the questions we might ask about a society in transition is to what extent its gender order has changed or is changing. The present paper sets out to read the country's transformation drama through the lens of contested conceptions of South African masculinity. The article is focused on one particular version of masculinity which it terms “rational-intellectual man,” and the argument is that a legacy of racism and the persistence of racialized modes of reasoning continue to marginalise black men from this and other powerful, high-status forms of hegemonic masculinity.
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Electrocatalysis of asulam on cobalt phthalocyanine modified multi-walled carbon nanotubes immobilized on a basal plane pyrolytic graphite electrode
- Authors: Siswana, Msimelelo P , Ozoemena, Kenneth I , Nyokong, Tebello
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6595 , http://hdl.handle.net/10962/d1004344
- Description: This work describes the electrochemical properties of cobalt tetra-aminophthalocyanine (CoTAPc) complex electropolymerized at the surface of multi-walled carbon nanotube (MWCNT) abrasively immobilized onto a basal plane pyrolytic graphite electrode (BPPGE). The constructed electrode displayed excellent electrocatalytic behaviour towards the oxidation of the herbicide, asulam, as evidenced by the enhancement of the oxidation peak current (~6 times) and the shift in the oxidation potential to lower values (by ~120 mV) in comparison with the bare BPPGE. The chronoamperometric detection of asulam which was carried out in 0.10 M phosphate buffer (pH 7.0) at a fixed potential of 0.65 V (versus Ag|AgCl) yielded excellent analytical parameters; a linear concentration range of 4.5–20 μM, a sensitivity of 241 × 10[superscript −3] μA/μM, a detection limit of 1.15 μM asulam (using the Y[subscript B] + 3σ criterion) and a response time of ~2 s.
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