Histological validation of gonadal macroscopic staging criteria for Labeo cylindricus (Pisces: Cyprinidae)
- Authors: Booth, Anthony J , Weyl, Olaf L F
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124593 , vital:35634 , https://doi.org/10.1080/15627020.2000.11657094
- Description: Histological examination of gametogenesis revealed that the current staging criteria used to assess gonadal recrudescence of the redeye labeo, Labeo cylindricus, were adequate. Gametogenesis was qualitatively similar to that of freshwater teleosts with a clearly defined seasonal reproductive cycle. L. cylindricus undergoes seasonal gross morphological and cytological gonadal changes with previtellogenesis dominating during the winter, vitellogenic development during spring and summer culminating in large-scale spawning at the end of summer. Post-spawning mass atresia of oocytes was evident in autumn. The histological data presented support macroscopical evidence that L. cylindricus is a synchronous iteroparous spawner, reproducing over a short period each year throughout its life-span.
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To be Xhosa or not to be Xhosa… that is the question:
- Authors: De Klerk, Vivian A
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/158096 , vital:40148 , https://doi.org/10.1080/01434630008666401
- Description: It has long been recognised that indigenous languages are endangered because of powerful social, political and economic pressures. In South Africa, the legacy of apartheid has left its indigenous languages particularly vulnerable, and since 1994 huge efforts have been made to reverse the situation. Despite the new language policy and accompanying legislation, it would seem that many Xhosa speakers themselves want English, and not Xhosa,for their children. This paper reports on a multi-faceted quantitative and qualitative survey in and around Grahamstown in the Eastern Cape Province, which focused on the steady trickle of speakers of Xhosa into English-medium schools in thearea, and examined the reasons underlying decisions to send Xhosa children to these schools and the subsequent linguistic and psycho-social effects of the move on the children.
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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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Language shift in Grahamstown: A case study of selected Xhosa-speakers
- Authors: De Klerk, Vivian A
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/158106 , vital:40149 , https://0-doi.org.wam.seals.ac.za/10.1515/ijsl.2000.146.87
- Description: A number of scholars (Fasold 1984; Aitchison 1991; Denison 1977; Dorian 1980; Gal 1979) have examined the issue of language maintenance and shift, trying to discover why certain languages (or language variants) sometimes replace each other among some Speakers, particularly in certain domains of linguistic behaviour under some conditions or intergroup contact. This article provides an overview of the main factors that have been identified as playing an important role in influencing language shift and then reports on the relative importance of these factors in a survey that examined the experiences and attitudes of Xhosa-speaking parents who have recently chosen to send their children to English-medium schools in Grahamstown (Eastern Cape, South Africa). The research was carried out during 1998, and the project was a multifaceted quantitative and qualitative longitudinal study involving responses to a postal questionnaire sent to all non-English parents at English-medium schools in the town, and follow-up Interviews with 26 parents.
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Discourse domination?: the role of gender in seminar interaction
- Authors: De Klerk, Vivian A , Hunt, Sally
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/139160 , vital:37710 , https://www.ajol.info/index.php/salas/article/view/6501
- Description: This paper focuses on the effect of the gender of participants on the discourse patterns of university seminars, and compares the interaction patterns in two undergraduate seminars with those in two post-graduate seminars at Rhodes University. In the undergraduate seminars, two different groups of students at first year level in different disciplines were videotaped. The major difference was in terms of composition: in one seminar, there were equal numbers of male and female students, while in the other, female students dominated numerically (75%). In addition, five of the six formed a close-knit group of friends, which proved to be an important factor in the analysis. At the postgraduate level, the student participants were identical and met in the same venue and at the same time on two successive days to discuss the same topic (affirmative action in the workplace). The important difference between the two classes was the fact that the first seminar was led by a female tutor and the second seminar by a male tutor, both under 40 years of age and white, both members of staff in the department, and both known to the students. The discourse patterns in these two sets of seminars were analysed in order to investigate the ways in which the gender of tutors and students influenced the floor-winning and floor-holding conventions of participants.
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Behavioural interactions of predators and spawning chokka squid off South Africa: towards quantification
- Authors: Smale, Malcolm J , Sauer, Warwick H H , Roberts, Michael J
- Date: 2001
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123921 , vital:35516 , https://doi.10.1007/s002270100664
- Description: The interaction of a suite of predators with mating and spawning chokka squid (Loligo vulgaris reynaudii) was studied at inshore (<50 m) spawning grounds off South Africa. This study provides the first detailed records of predator–prey interactions of squids on their spawning grounds and is the first attempt to time disruptions caused by predators to the egg-laying behaviour of squids, thereby quantifying the perceived threat to the prey. The squids are focused on mate choice and reproduction while they aggregate over egg beds and they may be more vulnerable to predation than at other times. Their vulnerability to different predators in the field is examined and the tactics used against different predatory species are illustrated using recordings made with underwater video cameras. Predators recorded included two cephalopods (Octopus vulgaris and L. v. reynaudii), five teleosts (Pagellus bellotii natalensis, Spondyliosoma emarginatum, Pachymetopon aeneum, Cheimerius nufar and Pomatomus saltatrix), seven chondrichthyians (Squalus megalops, Mustelus mustelus, Carcharias taurus, Dasyatis brevicaudata, Gymnura natalensis, Poroderma africanum and P. pantherinum) and three marine mammals (Arctocephalus puscillus, Tursiops aduncus and Delphinus delphis). Analysis of behavioural interactions between predators and prey showed that predator disruption of egg laying may be quantified in terms of time. Marine mammals caused the most acute disruption, whereas other taxa had more chronic disruption effects because they spent more time on the spawning grounds. During November 1995, the suite of predators changed during the course of a 2-day period of underwater video recording, possibly because of an increase in water temperature. The hypothesis that predators would be concentrated around a spawning aggregation was tested by surveying the spawning ground using an underwater camera towed by a boat navigating with differential GPS. The results supported the hypothesis because predators were located only around the spawning sites. The serial spawning of chokka squids in recently upwelled water may reduce predation pressure. Furthermore, it may be difficult for predators to predict the specific spawning site on a particular day because squids disperse away from egg beds at night and use numerous spawning sites along the coast.
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Spatial aspects of the reproductive and feeding biology of the striped robber, Brycinus lateralis (Pisces: Characidae), in the Okavango Delta, Botswana
- Authors: Booth, Anthony J , McKinlay, Bruce W
- Date: 2001
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/127020 , vital:35944 , https://doi.10.1080/15627020.2001.11657111
- Description: The Okavango Delta is a vast inland wetland system situated in northern Botswana. High rainfall is received in early summer in the southern Angolan highlands and throughout the Delta with the flood waters reaching the upper riverine floodplain between March and May where it percolates through to the lower drainage rivers between July and September. Aspects of the reproductive and feeding biology of two allopatric populations of the striped robber, Brycinus lateralis, a small characin species inhabiting the northern riverine floodplain and southern drainage rivers, were investigated. Both populations were similar in the biological aspects studied, with the flood cycle having little influence on the timing of reproduction, sexual maturity and dietary composition. Female fish from both populations matured sexually at 57mmSL, breeding over a protracted period during the warm, summer months. In both populations, the sex ratio was female-dominated at 4.8:1 (riverine floodplain) and 2.2:1 (drainage rivers). The striped robber is an opportunistic micro-carnivore with immature fish feeding predominantly on Daphnia spp. and adults being largely insectivorous.
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A 1394-based Architecture for professional audio production
- Authors: Moses, Bob , Laubscher, Rob , Foss, Richard
- Date: 2000
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427318 , vital:72430 , https://www.aes.org/e-lib/browse.cfm?elib=9092
- Description: With the advent of the IEEE 1394 standard, many audio device manufacturers have anticipated its employment within audio production systems, with the hope that future audio production systems will utilize this single connection type for the transmission of all audio and control data. This paper outlines extensive work that has been performed on the design and implementation of 1394 audio production components and, in the process, describes the resolution of the problems that arise when audio and audio device control data pass across 1394.
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A portfolio of original compositions with a commentary
- Authors: Nkuna, Musa
- Date: 2000
- Subjects: String quartets -- Scores Song cycles -- Scores Music -- Africa -- Scores
- Language: English
- Type: text , Thesis , Masters , MMus
- Identifier: vital:2698 , http://hdl.handle.net/10962/d1018689
- Description: This portfolio consists of four diverse original compositions written in 1999 : a string quartet, a cello suite and a set of two choral pieces.
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Academic literacy in management education
- Authors: Pearse, Noel J , Amos, Trevor L
- Date: 2000
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/270065 , vital:54392 , xlink:href="https://hdl.handle.net/10520/EJC36783"
- Description: Although management education aims to equip students with relevant knowledge, skills and competencies, making explicit and developing the cognitive thought processes necessary for management students to deal effectively with the current and future demands of the world of work, have been neglected. This article argues for the development of "complicated understanding" (Bartunek, Gordon and Weathersby 1983) in management students, through cultivating academic literacy. Using mediation, reflective inquiry and reflective writing interactively, it is illustrated how academic literacy could be promoted at the post-graduate level.
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AES-24 and MIDINet-A Comparative Study of Their Object Models and Implementations
- Authors: Foss, Richard , Klinkradt, Bradley
- Date: 2000
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427390 , vital:72435 , https://www.aes.org/e-lib/browse.cfm?elib=9220
- Description: AES-24 and MIDINet object models have been used to create corresponding implementations. Both implementations utilize a network of IBM PCs running the Windows operating system. The transport protocol in each case is the Internet Protocol (IP). The object models of the two systems have some differences and similarities that have an impact on the application protocols. Arising from this study are pointers toward the incorporation of MIDI transport into the AES-24 framework.
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An investigation into the neuroprotective properties of ibuprofen
- Authors: Lambat, Zaynab Y , Conrad, Natasha , Anoopkumar-Dukie, Shailendra , Walker, Roderick B , Daya, Santylal
- Date: 2000
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184335 , vital:44209 , xlink:href="https://doi.org/10.1023/A:1011115006856"
- Description: There is increasing evidence suggesting a protective role for anti-inflammatory medications in neurological disorders such as Alzheimer's disease (AD). While there has not been any direct evidence for this, a number of clinical studies indicate that those patients who have had a history of nonsteroidal anti-inflammatory use, have a lower incidence of AD. Since there is currently no evidence on the mechanism by which these agents offer possible neuroprotection, we investigated the potential neuroprotective properties of the nonsteroidal anti-inflammatory drug, ibuprofen, by examining whether this agent could reduce lipid peroxidation and superoxide radical generation. Quinolinic acid and cyanide, known neurotoxins, were used to induce lipid peroxidation and superoxide anion formation respectively, in rat brain homogenate. The results show that ibuprofen significantly (p more than 0.05) reduced quinolinic acid-induced lipid peroxidation and cyanide-induced superoxide production. The results of the present report therefore suggest a possible mechanism for the neuroprotective effect of ibuprofen.
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Application of the Minolta chromameter to the assessment of corticosteroid-induced skin blanching
- Authors: Walker, Roderick B , Haigh, John M , Smith, Eric W
- Date: 2000
- Language: English
- Type: Book chapter , text
- Identifier: vital:6451 , http://hdl.handle.net/10962/d1006639
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Bread and honour: white working class women and Afrikaner Nationalism in the 1930s
- Authors: Vincent, Louise
- Date: 2000
- Language: English
- Type: text , Article
- Identifier: vital:6205 , http://hdl.handle.net/10962/d1008575
- Description: Women have occupied a central place in the ideological formulations of nationalist movements. In particular, the figure of woman as mother recurs throughout the history of nationalist political mobilizations. In Afrikaner nationalism, this symbolic female identity takes the form of the volksmoeder (mother of the nation) icon, commonly assumed to describe a highly circumscribed set of women's social roles, created for women by men. The academic orthodoxy holds that middle-class Afrikaner women submitted to the volksmoeder ideology early on in the development of Afrikaner nationalism but that the working class Afrikaner women of the Garment Workers' Union (GWU) represented an enclave of resistance to dominant definitions of ethnic identity. They chose instead to ally themselves with militant, class-conscious trade unionism. This paper argues that Afrikaner women of different classes helped to shape the contours of the volksmoeder icon. Whilst middle class Afrikaner women questioned the idea that their social contribution should remain restricted to narrow familial and charitable concerns, prominent working class women laid claim to their own entitlement to the volksmoeder heritage. In doing so, the latter contributed to the popularization and reinterpretation of an ideology that was at this time seeking a wider audience. The paper argues that the incorporation of Afrikaner women into the socialist milieu of the GWU did not result in these women simply discarding the ethnic components of their identity. Rather their self-awareness as Afrikaner women with a recent rural past was grafted onto their new experience as urban factory workers. The way in which leading working class Afrikaner women articulated this potent combination of 'derived' and 'inherent' ideology cannot be excluded from the complex process whereby Afrikaner nationalism achieved success as a movement appealing to its imagined community across boundaries of class and gender.
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Cape Town talks about sex workers
- Authors: Sex Workers’ Education & Advocacy Taskforce (SWEAT)
- Date: 2000
- Subjects: SWEAT
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/168829 , vital:41651
- Description: On Monday 25 September,, as- part of the One City Festival, the Black Arts Collective hosted a debate about sex work. Natasha from SWEAT spoke about the why the government should decriminalize sex work. Khadija Magardie, a journalist from the Mail and Guardian newspaper, sent a speech talking about how sex work should be abolished by changing the law to make the clients criminals, so they can be arrested for buying sex from sex workers. Members of the public came to the debate, and talked about their feelings about sex work, and asked questions and gave comments. Generally most people were supportive of the fact that sex workers deserve human rights, even if they didn’t like the idea that people sell sex for a living. The city is starting to talk about sex work and sex workers, which is very exciting. It is a chance for SWEAT to talk about the realities of the industry, and to break down some of the stereotypes that many members of the public have about sex workers and sex work. One element that is missing from these discussions is the voices of sex workers themselves. SWEAT points out that it is very difficult for sex workers to talk publicly because of the stigmatization they suffer, and because sex work is still illegal. If you are interested in talking to the public about your experiences and opinions, please contact SWEAT and let us know, so that next time there is a chance to speak to the public we can invite you along.
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Comparative Spectroscopic and Electrochemical Properties of Bis (octakis (dodecylthio) naphthalocyaninato) europium (III) and Bis (tetra-tert-butylnaphthalocyaninato) europium (III) Complexes
- Authors: Nyokong, Tebello , Furuya, Fumio , Kobayashi, Nagao , Du, Daming , Liu, Wei , Jiang, Jianzhuang
- Date: 2000
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/293174 , vital:57062 , xlink:href="https://doi.org/10.1021/ic990483b"
- Description: Bis(substituted-2,3-naphthalocyaninato)europium(III) complexes: bis(octakis(dodecylthio)-2,3-naphthalocyaninato)europium(III) {Eu[2,3-Nc(SC12H25)8]2, 1} and bis(tetra-tert-butyl-2,3-naphthalocyaninato)europium(III) {Eu[2,3-Nc(t-Bu)4]2, 2} have been synthesized by cyclic tetramerization of naphthalonitriles with Eu(acac)3·H2O in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in refluxing n-octanol. These compounds were characterized by UV−visible, magnetic circular dichroism (MCD), near-IR, IR, EPR, and mass spectroscopies. The absorption and MCD spectra of 1 showed splitting of the Q band, with peaks at 700 and 784 nm, red shifted from the Q band of 2 at 763 nm. The absorption and MCD spectral band deconvolution calculations of complex 1 gave two A terms in the Q-band region. The A terms are assigned to 2A2 → 2E1 transitions. Cyclic voltammograms of 1 and 2 showed reversible oxidation couples at E1/2 = −0.28 V (for 2) and −0.25 V (for 1) vs ferrocenium/ferrocene (Fc+/Fc). The second oxidation exhibited a complicated behavior for both complexes. The reduction couples for 2 were observed at E1/2 = −0.61, −1.64, −1.97, and −2.42 V, and for 1 they were observed at E1/2 = −0.62, −1.60, −1.86, and −2.27 V vs Fc+/Fc. Spectral changes observed on chemical oxidation and reduction of the complexes are presented, and the behaviors of 1 and 2 are compared.
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Comparison of plant diversity in protected and communal lands in the Bushbuckridge lowveld savanna, South Africa
- Authors: Shackleton, Charlie M
- Date: 2000
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181885 , vital:43777 , xlink:href="https://doi.org/10.1016/S0006-3207(00)00001-X"
- Description: Patterns of higher plant species richness and beta diversity were assessed using standard Modified-Whittaker plots in relation to land use, slope position and mean annual rainfall across a rainfall gradient in the savanna areas of the Bushbuckridge lowveld, South Africa. In particular, comparison of communal areas with adjacent protected areas was important in showing the impacts of potential changes in land use within an overarching catchment management plan. Although most of the protected areas considered preservation of biodiversity as their primary goal, they were characterised by significantly fewer plant species than the adjacent, highly utilised, communal lands, at both the plot and point scale. Slope position also had a significant effect on plant species richness, with eutrophic bottomlands having c. 30% more species than the dystrophic toplands. This adds weight to the need for greater public awareness for the judicious use and management of the sensitive bottomlands, which fringe the primary drainage lines that are vital for sustained supplies of good quality surface water in this semi-arid environment. The total number of species increased with increasing mean annual rainfall across the rainfall gradient. This suggests that, if the catchment management plan aims to identify additional areas for conservation, the higher rainfall areas should be the first to be assessed. Species turnover was greater along the rainfall gradient than the catenal gradient between toplands and bottomlands.
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Cyanide-induced free radical production and lipid peroxidation in rat brain homogenate is reduced by aspirin
- Authors: Daya, Santylal , Walker, Roderick B , Anoopkumar-Dukie, Shailendra
- Date: 2000
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184346 , vital:44210 , xlink:href="https://doi.org/10.1007/BF02674529"
- Description: The neuroprotective properties of aspirin were investigated using cyanide-induced neurotoxicity as model. Cyanide, a known neurotoxic agent significantly increased lipid peroxidation and superoxide anion levels in rat brain homogenate in a concentration-dependent manner (0.25–1.0 mM). When homogenate, containing 1.0 mM KCN was cotreated with aspirin (1.0 mM) there was a significant decrease in lipid peroxidation. Aspirin (0.5 mM and 1.0 mM) also significantly reduced KCN-induced superoxide anion generation. The results of the present report therefore indicate a neuroprotective role for aspirin.
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