A study of the transdermal drug diffusion properties of rooperol tetra-acetate
- Authors: Pefile, Sibongile C.
- Date: 1998 , 2013-08-29
- Subjects: Transdermal medication , Skin absorption , Dermatologic agents
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3838 , http://hdl.handle.net/10962/d1007649 , Transdermal medication , Skin absorption , Dermatologic agents
- Description: The rapidly growing interest in the potential use of topical drug delivery formulations has resulted in increased use of the skin as a vital port for drug delivery. Extensive research has been conducted in designing vehicles capable of delivering a desired amount of drug to a specific site, to produce the desired pharmacological response. Rooperol tetra-acetate is a lipophilic, cytotoxic drug with the potential for use in the treatment of solar keratosis. For effective pharmacological action, delivery of the drug to the epidermal/dermal junction of the skin is required. A study of the topical penetration properties of rooperol tetra-acetate from different topical bases, each possessing different physico-chemical properties, was performed. The assessment involved a comparison of the diffusion properties under occlusive and non occlusive conditions when the drug was formulated into a gel, Cetomacrogol Cream B.P. (oil-inwater), Simple Ointment B.P. and an extemporaneously prepared water-in-oil topical cream. The in vitro experiments were conducted using polydimethylsiloxane and rat membrane mounted in a Franz diffusion cell. The topical permeation kinetics of rooperol tetra-acetate were determined by exploring the release characteristics of the active ingredient from the vehicles formulated and the permeability properties of the drug through the membranes employed. Further studies involved investigating the utilization of supersaturated systems intended to increase the thermodynamic activity of the drug when formulated into a propylene glycol/water vehicle (with and without polymer). To measure the release of rooperol tetra-acetate into the skin from a topical base it was necessary to, firstly, develop a suitable quantitative method for the analysis of the active drug in the aqueous receptor phase of in vitro diffusion cells. The second stage of product development was the design of an effective delivery system to facilitate the release of the diffusant from its base. A high performance liquid chromatographic method was utilized for the identification and quantification of the active drug. As validation is an important aspect in the development and subsequent utilization of an analytical procedure, the developed HPLC technique was validated by determining the precision, accuracy, range, limit of quantitation and sensitivity of the system. Lastly, the stability of rooperol tetra-acetate at elevated temperatures was assessed and a stability profile of the drug was generated for the three-month period of analysis. The results obtained following chromatographic analysis of the receptor phase sampled during the diffusion experiments indicate that the gel and oil-in-water formulations most effectively promoted the diffusion of rooperol tetra-acetate across polydimethylsiloxane membrane. The water-in-oil system exhibited lower flux rates and the ointment showed the least drug release. Occlusion of the topical vehicle increased the diffusitivity of the permeant from all formulations analysed. The permeation assessment results of the supersaturated systems showed enhanced diffusion of rooperol tetra-acetate across polydimethylsiloxane and rat membrane. The high thermodynamic activity existing in supersaturated systems most effectively increased the driving force for drug diffusion resulting in enhanced percutaneous penetration of rooperol tetra-acetate beyond the release and transport limitations of saturated solutions. These results provide the basis on which an effective topical drug delivery vehicle may be designed for this new drug entity.
- Full Text:
- Date Issued: 1998
A nutritional evaluation of effluent grown algae and zooplakton as feed ingredients for Xiphohorous helleri, Poecilia reticulata and Poecilia velifera (Pisces : Poeciliidae)
- Authors: Potts, Warren M
- Date: 1998
- Subjects: Poeciliidae , Poeciliidae -- Nutrition , Zooplankton , Algae , Poeciliidae -- Feeding and feeds
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5306 , http://hdl.handle.net/10962/d1005151 , Poeciliidae , Poeciliidae -- Nutrition , Zooplankton , Algae , Poeciliidae -- Feeding and feeds
- Description: The aim of this study was to evaluate the nutritional value of algae and zooplankton grown in an algal integrated ponding system for poeciliids. The available information on the nutritional requirements of poeciliids was compared with a proximate analysis of the algae and zooplankton. The effluent grown algae and zooplankton had a crude protein value of 41.47 ± 0.2% and 36.84 ± 0.3%, a lipid content of 4.8 ±. 0.4% and 11.1 ± 0.8% and a carbohydrate content of 35.13 ± 0.8% and 31.06 ± 0.6% respectively. These values compared favourably with those of the known nutritional requirements of poeciliids. To test if the nutritional value of the algae and zooplankton in the AlPS was constant, the species composition of the algae and the crude protein content of the algae and zooplankton in the high rate oxidation ponds were measured monthly and bi-weekly for a year respectively. The species composition remained fairly stable for the duration of the experiment and the average protein composition of the algae and zooplankton was 43.4 ± 4.4% and 38.6 ±2.8% respectively. This indicated that the algae and zooplankton in the AlPS provided high protein biomass through the year. The quality of the effluent grown algal and zooplankton biomass was evaluated by analysing their amino acid composition and comparing it with the amino acid composition of the body tissue of X. helleri. With respect to the amino acid composition of the body tissue of X. helleri, the amino acid profile of the algae had a 69% and the zooplankton a 63% similarity. The quality of the pure algal and zooplankton protein was also tested biologically, by feeding them directly to poeciliids during a ten week growth trial. The algae and zooplankton diets did not result in adequate growth compared to poeciliids which were fed a formulated control diet. The initial growth trial also evaluated the effect of processing on the chemical composition of the algae and its biological effect on fish fed with it. There were no significant differences in the chemical composition of fresh and sun dried algae and this was reflected in the growth rates of the fish which did not differ significantly. Freeze dried algae had a lower crude protein content than fresh and sun dried algae and a poorer amino acid composition. Fish fed freeze dried algae exhibited poorer growth and survival in comparison to the other treatments. The gut transit times of X. helleri and the gastric evacuation times of poeciliids were determined using colour dyes incorporated in the diet and by sacrificing fish at predetermined intervals after feeding respectively. The gut transit time of X. helleri fed a sun dried algal diet and a formulated diet was 225 ± 8.55 minutes and 261.93 ± 10.86 minutes respectively. The gastric evacuation times of X. helleri, P. reticu/ata and P. velifera were 7, 9 and 8 hours respectively. Since the maximum amount of food in the hindgut after feeding was detemined to be 3, 5 and 3 hours in X. helleri, P. reticulata and P. velifera respectively, fish were sacrificed at these times in the digestibility study. The digestibility of sun dried algae was determined using 1 % chromic oxide as an internal marker in the algae. The apparent crude protein digestibility of sun dried effluent grown algae ranged from 65%-75% in the three poeciliid species. Based on the results of the chemical and biological analysis of the algae and zooplankton, conventional diets incorporating algae at 5% and 20% protein inclusion levels were formulated. These diets and a treatment in which zooplankton, reared in the AlPS were fed as a dietary supplement to a formulated diet were fed to poeciliids for twelve weeks. No significant differences in the growth of poeciliids fed any of the test diets were observed. It was concluded that the algae could be incorporated into poeciliid formulated diets up to level of 20% protein inclusion without any negative effect on the growth of the fish. The chemical and biological evaluation of the algae suggested that it had a similar nutritional quality to soyabean meal. Poeciliid growth was not enhanced with a zooplankton supplement, however a possible low feeding rate by poeciliids on the zooplankton as a result of their small size may have affected the result. The colour enhancement potential of effluent grown algae and zooplankton was evaluated biologically in ten and twelve week growth trials using visual observation (31 people) and by using a chromameter. While pure, sun dried algae significantly enhanced the colour of P. reticulata, no significant differences in the colour of poeciliids were observed or recorded when fish were fed diets incorporating sun dried algae up to levels of 20% protein inclusion. The effect of effluent grown algae and zooplankton on poeciliid health was also tested biologically in the ten and twelve week growth trials. The high mortalities (75%-84%) recorded for X. hel/eri when fed the pure algal and zooplankton diets were considered to be as a result of the nutritional inadequacy of the diets since there were significantly less mortalities in fish fed the formulated control diet and 63% of the fish that died during the course of the trial were emaciated. In addition, fewer mortalities (10%-40%) were recorded in X. hel/eri fed the nutritionally adequate formulated diets in the twelve week growth trial. No symptoms of disease were recorded in the twelve week growth trial and the algae was considered to have no toxicological or pathological effects on poeciliids. Centrifugation, sand filtration, sedimentation, microstraining and biological harvest were evaluated as methods of small scale algal harvest from the high rate oxidation ponds. Algae could be harvested most efficiently with little associated labour by sedimentation (without flocculating agents) and by microstraining with 60IJm mesh. Effluent grown algae can replace conventional feed ingredients up to a level of 20% protein inclusion without negatively effecting the growth, colour, health or survival of poeciliids.
- Full Text:
- Date Issued: 1998
Reproductive behaviour of the skunk clownfish, Amphiprion akallopisos, under captive conditions
- Authors: Haschick, Rory Dean
- Date: 1998
- Subjects: Anemonefishes -- Spawning , Amphiprion -- Reproduction , Fishes -- Reproduction , Hatchery fishes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5316 , http://hdl.handle.net/10962/d1005161 , Anemonefishes -- Spawning , Amphiprion -- Reproduction , Fishes -- Reproduction , Hatchery fishes
- Description: The objectives of the study were to determine whether or not behaviour could be used to predict spawning in Amphiprion akallopisos, and to document the behaviour of this species under various environmental conditions in captivity. The spawning behaviour of A. akallopisos was studied and quantified. Three behaviour patterns - belly touching, nest cleaning by the female and mutual nest cleaning (by the male and the female) were identified as predictors for spawning. The reproductive behaviour of A.akallopisos under three photoperiods was investigated. The photoperiods were: 14L:10D, 10hr15minL:13hr45minD and a natural photoperiod cycle condensed into three months. A. akallopisos maintained under 14 L:10D exhibited a significantly higher frequency and duration of chasing, nest cleaning and total interaction compared to fish kept under 10hr15minL:13hr45minD. A photoperiod of 14L:10D was selected for further studies. As manipulation of photoperiod did not induce spawning, GnRHa was administered to the fish in the diet at levels of 10, 20, 40 and 80 μg/kg BW. Control groups were fed untreated food. None of the dosages were successful in inducing spawning, or spawning behaviour in A. akallopisos. It is possible that the method of hormone application was not suitable for this species. It is also possible that behaviour may regulate blood hormone levels as opposed to endocrine status influencing behaviour. In the third trial, A. akallopisos was maintained with, and without sea anemones in order to determine whether or not anemone hosts are necessary for spawning. The presence of anemones did not induce spawning and A. akallopisos kept without anemones exhibited significantly more interactive behaviour than fish kept with hosts. Spawning of A. akallopisos at a later date without anemones suggests that anemones are not necessary for spawning in A. akallopisos. Light intensity was investigated as a cue for spawning. The reproductive behaviour of A. akallopisos was then studied under light intensities of 4.16 x 10¹⁵ quanta.sec⁻¹.cm⁻², 8.85 x 10¹⁵ quanta.sec⁻¹.cm⁻² and this intensity plus natural light. Spawning occurred mainly under 8.85 x 10¹⁵ quanta.sec⁻¹.cm⁻². Fish maintained under this light intensity exhibited significantly more of nest cleaning behaviour in terms of frequency and duration than fish maintained under low light intensity. A minimum light intensity of 8.85 x 10¹⁵ quanta. sec⁻¹.cm⁻² is recommended for conditioning of this species. This study can be of practical relevance to hatchery managers who can use the methods developed and record predictors for spawning in A. akallopisos and other Amphiprion species. In this way imminence of spawning may be estimated. Most importantly, the study also has academic merit as little work has been undertaken in this field. Although the observational method used in this study was adequate for the purposes of the investigation, future work of this nature should incorporate other methods of documenting gonadal development such as gonadal staging and GSI in order to obtain more conclusive results.
- Full Text:
- Date Issued: 1998
Transformational leadership and organisational effectiveness in the administration of cricket in South Africa
- Authors: Ristow, Adrian
- Date: 1998
- Subjects: Cricket--South Africa , Cricket -- South Africa -- Management , Sports administration -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1182 , http://hdl.handle.net/10962/d1002799 , Cricket--South Africa , Cricket -- South Africa -- Management , Sports administration -- South Africa
- Description: After years of isolation from the international sporting arena, South African sports teams have recently achieved much success. This study is concerned specifically with managing for organisational effectiveness in South African cricket. According to the theory of transformational leadership, there should be a positive relationship between this style of leadership and organisational effectiveness. The Multifactor Leadership Questionnaire was used to collect information about leadership while data for organisational effectiveness, the dependent variable, was collected using the Effectiveness Survey for Cricket Administration. Most of the results regarding the relationship of the transformational leadership factors and organisational effectiveness were significant. On the other hand, most of the results regarding the relationship of the transactional leadership factors and organisational effectiveness were not significant. The overall results provide general support of the relevance of the transformational leadership theory in the context of cricket administration in South Africa. The results also support Bass's (1990b) argument of the universal application of the transformational leadership theory.
- Full Text:
- Date Issued: 1998
Ecological interactions on a rocky shore : the control of macroalgal distribution by intertidal grazers
- Authors: Whittington-Jones, Kevin John
- Date: 1998
- Subjects: Limpets -- South Africa , Mollusks -- Ecology , Mollusks -- Feeding and feeds , Mollusks -- South Africa , Cryptogams , Cryptogams -- South Africa , Algae -- Control , Algae -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5665 , http://hdl.handle.net/10962/d1005350 , Limpets -- South Africa , Mollusks -- Ecology , Mollusks -- Feeding and feeds , Mollusks -- South Africa , Cryptogams , Cryptogams -- South Africa , Algae -- Control , Algae -- South Africa
- Description: The aim of the present study was to determine the potential impact of intertidal grazers on the distribution of macro algae on the south coast of South Africa. Particular attention was paid to the large patellid limpet, Patella oculus, which is found thoughout the intertidal zone. Studies of gut contents revealed that Patella oculus was capable of ingesting not only the thallus of foliose (eg. Ulva spp.) and encrusting coralline macroalgae, but also spores and diatoms. The inclusion of these relatively small particles in the diet was surprising, as electron micrographs of the radula of P.oculus revealed that it is typically docoglossan in structure. Such radulae are thought to be poorly suited for collecting small food particles. Sand made up a significantly higher proportion of the gut contents than other particles at all shore heights, which suggests that P.oculus might be capable of excavating the rocky substratum, or of sweeping up sand, while searching for food. Analysis of the gut contents of other local herbivorous molluscs, was also carried out. These species included the winkles, Oxystele variegata and O.sinensis, and the small pulmonate limpets, Siphonaria concinna, S.capensis, and S.serrata. The guts of all species contained mainly spores and diatoms, although small fragments of Ulva sp. were found. The population structure of Patella oculus was investigated at two sites, Cannon Rocks and Old Woman's River. At Cannon Rocks, mean shell length of low-shore animals was significantly lower than that of both mid- and high-shore animals, while at Old Woman's River, no significant difference was found among shore heights. A regression equation for In (shell length) vs In (dry weight) was calculated, and based on length data, the biomass density (g dry mass.m⁻²) of P.oculus at Old Woman's River was estimated. Values ranged from 2.8 on the low- and midshore to 0.37 on the high-shore. A manipulative field experiment was used to determine the impact of mesograzers and macrograzers (such as Patella oculus) on the distribution of intertidal macro algae on the mid- and low-shore at Old Woman's River. Grazers were excluded using mesh cages (mesh size = 3mm), in two separate experiments, one in winter and the other in spring. Percentage cover of macroalgal species and sessile invertebrates was estimated at approximately 6 week intervals for up to 3 months. MANOV A showed that treatments did not significantly affect cover of macroalgae or barnacles during winter. However, towards the end of the spring experiment (midshore only) cover of barnacles and green foliose turfs did increase in those plots from which mesograzers and/or macro grazers were excluded. The failure of the statistical tests to detect significant differences at some time intervals may have been caused by high levels of variation among replicates. This suggests that factors other than grazing are of overriding importance in determining the distribution of local macroalgae. The existence of a possible symbiotic relationship between Patella oculus and the red foliose alga, Gelidium pristoides, was investigated. The availability of various substratum types, including rock, limpet shells, barnacles etc., and the proportion of the total cover of G.pristoides on each, was calculated. It was shown that a significantly higher proportion of the alga grew on limpet shells, although the availability of this substratum type was low. It is thought that the aggressive behaviour of P.oculus prevents all but juvenile Patella longicosta from grazing on its shell, thus providing a refuge from grazing for G.pristoides.
- Full Text:
- Date Issued: 1998
Ammophila arenaria (L.) Link (marram grass) in South Africa and its potential invasiveness
- Authors: Hertling, Ursula Margret
- Date: 1998
- Subjects: Grasses -- South Africa Alien plants -- South Africa Sand dune plants -- South Africa Grasses -- Ecology -- South Africa Sand dune ecology -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4198 , http://hdl.handle.net/10962/d1003767
- Description: Ammophila arenaria (L.) Link is a European sand binding plant which was introduced to South Africa in the 1870's for the purpose of dune stabilisation. Because of its known invasiveness along the west coast of North America, and the problems South African ecosystems experience with alien invader plants, it was deemed necessary to study the biology and ecology of this species in South Africa. The aim of this thesis is to establish the potential invasiveness of A. arenaria on Cape coastal dunes and assess whether its use for dune stabilisation is still justifiable. A. arenaria occurs nowadays between the Langebaan area on the west coast and Gonubie in the Eastern Cape. Although widespread, the grass appears to occur only in areas where it has been planted. Its unaided spread may be prevented by adverse climatic conditions. Studies on the community biology of South African A. arenaria communities as compared to indigenous dune plant communities and natural A. arenaria communities in Europe cannot confirm the aggressive behaviour that A. arenaria shows in California and Oregon. In South Africa, A. arenaria does not exert strong floristic control over other species or outcompete and replace them, neither does it alter the topography of South African beaches and dunes. It forms weaker species associations and tends to develop communities of little species variability along the coast, thereby proving its alienness in South Africa, but this does not imply its invasiveness. Studies on succession of A. arenaria stabilisation areas show that monospecific A. arenaria plantings can be succeeded by a species-rich indigenous dune scrub or dune fynbos within a few decades. Plant-parasitic nematodes have been recorded, which may play an important role in the succession of A. arenaria stands in South Africa as was observed in Europe. Monitoring of A. arenaria communities and indigenous communities over nearly three years shows that A. arenaria is not spreading and replacing indigenous plants but in fact rather being replaced by the latter. A. arenaria profits from a superior sand burial tolerance but is affected by adverse climatic factors, mostly the lack of rainfall and strong radiation. In comparison to the indigenous dune grasses Thinopyrum distichum and Ehrharta villosa, it does not show any superior demographic traits such as an unusually high growth rate or large aboveground biomass production. Although A. arenaria produces viable seed in South Africa, the indigenous grasses show better germination and seedling establishment in the field. This study indicates that A. arenaria is not invasive in South Africa, nor likely to become an invader species in the near future. However, more research is required to confirm these results and more caution recommended regarding the further use of this alien grass for dune stabilisation.
- Full Text:
- Date Issued: 1998
Media reach and reception in development communication: the case of the Rural Industries Innovation Centre in Botswana
- Authors: Maleke, Jackson Mogopodi
- Date: 1998
- Subjects: Rural Industries Innovation Centre (Kanye, Botswana) , Communication in rural development , Mass media in community development
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3455 , http://hdl.handle.net/10962/d1002909 , Rural Industries Innovation Centre (Kanye, Botswana) , Communication in rural development , Mass media in community development
- Description: The study was conducted in Phitshane-Molopo in Botswana. Phitshane-Molopo is located about 115 kilometers south of the main village of Kanye in which the Rural Industries Innovation Centre operates. The study constitutes the first attempt at evaluating audience reach and reception of the RIIC media messages. In this study, a sample of 50 representatives of households (the rationale is covered in chapter 1) was taken, for which a questionnaire was administered, including conducting in-depth interviews with key informants. The study found that RIlC media are not reaching the audience in keeping with the corporate goals and assumptions on the basis of which the communication strategy was established. The audience has claimed that the print media relayed to them through the extension officer channel do not reach them. The study also found that the audience possessed adequate literacy skills and the majority of them could read materials produced in Setswana. Only a few individuals preferred media text produced in the English language. The study therefore deplores RIIC's proclivity towards producing its media texts only in the English language. This has tended to marginalise members of the audience who cannot read in English. It is thus hoped that this study would provide a learning experience for RIIC to consider producing its communication media in relation to the needs of the audience. The study also found that the impact of the RIIC radio programme is very poor, with only a low of 2% of the sample population having listened to this programme. The problem stems from the poor Radio Botswana transmission system. The audience said that for the larger part of the day, they can't get Radio Botswana on air. As a result, they have shifted their interest to the South African radio stations such as Radio Tswana and Radio Mmabatho, which are constantly on air. The study concludes that the RIIC communication strategy is failing in the study area because the paradigm in which it is located is somewhat flawed, as a result of which it does not effectively impact upon reach and reception. At the core of this failure rate are implementation problems and the lack of evaluation that would have picked up the - problems earlier, for which solutions would have been found. Consequently, th~$tudy recommends the need to explore the suitability and effectiveness of the indigenous media for possible syncretization with conventional media as recommended in the need based integrative model (Nwosu and Megwa: 1993). Indigenous media are ideally suited to rural communication needs because they are consistent with the socio-cultural expectations of the audience. RIIC therefore stands to benefit from these media because the bulk of its audience resides in rural areas.
- Full Text:
- Date Issued: 1998
Family diversity : a South African perspective focusing on Whites in Grahamstown
- Authors: Ziehl, Susan C
- Date: 1998
- Subjects: Families -- History -- Research Families -- South Africa -- Grahamstown Families Families -- Research -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3341 , http://hdl.handle.net/10962/d1004467
- Description: Drawing on developments in the field of family history and studies of families in contemporary settings, the study addresses the question of explaining variations in household patterns. Its empirical basis is a survey of White households in Grahamstown. The surveyed population was broken down in terms of class (occupation) and culture (language) and analyses conducted to determine if there are any statistically significant relationships between these variables and the tendency to reside in particular household structures. The question of 'family ideology' was also addressed as an attempt was made to uncover subjects' views on a variety of family-related issues. On the basis of the research results, a model of the relationship between class, culture and household structure was developed. Its application to a comparison of Black and White household structures in South Africa as well as the United States, is discussed. Finally, attempts at redefining the family are addressed and a new definition of the family proposed.
- Full Text:
- Date Issued: 1998
'n Intertekstuele studie : Die werfbobbejaan van Alexander Strachan
- Authors: Loots, Sonja
- Date: 1998
- Subjects: Strachan, Alexander Die Werfbobbejaan
- Language: Afrikaans
- Type: Thesis , Masters , MA
- Identifier: vital:3592 , http://hdl.handle.net/10962/d1002167 , Strachan, Alexander Die Werfbobbejaan
- Description: The title, "'n Intertekstuele studie: Die werfbobbejaan van Alexander Strachan", refers to an analysis of the way in which intertextual processes generate meaning in this text. It is analysed with specific regard to the way in which it enters into signifying and detennining relationships with other texts, notably texts by the same author. A significant part of the intertexts that are reassembled, refined, restated, amplified, contradicted or diffused throughout Die werfbobbejaan are located in other works in the Strachan oeuvre: n Wereld sonder grense (1984) and Die jakkalsjagter (1990). These three texts are related as a triptych of intertextual association, and the boundaries between them are not hermetically sealed. Intertextual activity in Die werfbobbejaan involves an intricate network of interfigural relationships. The identities of numerous characters in the text start to coincide with those of other characters to which they are linked intertextually. Characters travel across the boundaries supposedly separating "different" texts. The doubling and displacing of characters alert us to the fact that the text is not fixed within stable boundaries. Codes, scenes, snippets of dialogue and even moods also penetrate the boundaries between "different" texts and recur in the form of mirror images or ghostly transformations of themselves. These intertextual patterns mobilise an active reading process and unify the act of reading with that of writing in "a single signifying process" (Barthes 1979: 79). The narrator in Die werfbobbejaan is a woman writing a biography about an author. Reading his novels and unpublished manuscript she finds that the manuscript of her subject anticipates and later even dictates "extra-textual" reality and inserts her into the fiction. The way in which the biography is taken up in the play of intertextuality leads to the perception that the fictional author is an intertextual mirror image of the real author, who belongs to the extra-textual world outside the book. In this way intertextual activity in Die werfbobbejaan destabilizes the frame between fiction and reality. No reading of Die werfbobbejaan can be complete without taking into account the plurality of simultaneously perceived meanings triggered by intertextual activity in the text.
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- Date Issued: 1998
A social history of white working class women in industrializing Port Elizabeth, 1917-1936
- Authors: Gibbs, Patricia Anne
- Date: 1998
- Subjects: Women -- South Africa -- Port Elizabeth -- History , Women -- Employment -- South Africa -- Port Elizabeth -- History , Port Elizabeth (South Africa) -- History
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2543 , http://hdl.handle.net/10962/d1002395 , Women -- South Africa -- Port Elizabeth -- History , Women -- Employment -- South Africa -- Port Elizabeth -- History , Port Elizabeth (South Africa) -- History
- Description: The study period saw a significant increase in the urbanisation of whites and blacks in Port Elizabeth induced by droughts and coercive legislation, but also by burgeoning industrialisation. Industry had been given great stimulus by World War 1 and maintained by protectionist legislation in the 1920s which the local state and industrialists came to endorse. The ethos of the town was overwhelmingly British in terms of the population, the composition of the local council, business interests and the prevailing culture. Whites formed the largest component of the population in Port Elizabeth during the inter-war years. The majority of white women lived in the North End, the industrial hub and a major working class area of the city. Although the provision of housing was initially neglected, economic and subeconomic housing in the 1930s helped to create both racial separation and a sense of community between sectors of the working class. Yet, white working class women did not form a homogenous group, but rather consisted of different ethnic groups, occupations and classes. The Afrikaans speaking sector, formed a significant component of the industrial labour force especially in the leather, food and beverage and clothing industries. In a centre where white labour was favoured and marketed as an advantage to outside investors, they rapidly displaced coloured women. The female workforce was basically young, underpaid (especially in comparison to wages on the Rand) and temporary. While white women were still in evidence in other occupations such as domestic work and in the informal sector, their numbers here steadily diminished as both racial segregation and municipal regulation, were implemented. Against a background of chaotic social conditions, large slum areas and the spread of infectious diseases, the local council did much to improve health services particularly for women and children. Poor relief instituted in 1919 was, however, less forthcoming and female - headed households were often left to rely on the services of local welfare organisations. The extended family, however, was the norm affording support against atomization. Although pressurised by social ills throughout the period, the family was increasingly buttressed by state assistance. Prevailing morality was likewise actively constructed in terms of legislative repression and racial division. This often lead to social aberrations such as infanticide which was only reduced by the increase of state assistance and, in the longer term, social mobility of the whites.
- Full Text:
- Date Issued: 1998
The notion of commitment in selected works of Maishe Maponya
- Authors: Moorosi, Mabitle
- Date: 1998
- Subjects: Maponya, Maishe , Commitment (Psychology) in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2142 , http://hdl.handle.net/10962/d1002374 , Maponya, Maishe , Commitment (Psychology) in literature
- Description: This study is a critical analysis of selected works of the playwright Maishe Maponya namely, The Hungry Earth, Jika and Gangsters. The main thrust of the analysis of the thesis is centred on questions around what 'Commitment' might mean in literature and drama. This concept has appeared in many names and guises. In theatre, it has assumed names like Theatre of Commitment, Theatre of the Dispossessed, Theatre ofthe Oppressed, Theatre of Resistance, as well as Theatre of Radicalization (Bentley 1968; Boal 1974; Mda 1985; Maponya 1992). These names came into existence as a result of a concerted effort to refrain from the use of the traditional conventional theatre, which does not appear to address itself to societal problems - the preoccupation of Theatre of Commitment. Chapter One is principally concerned with the concept of Commitment and its implications in art and literature, more specifically in theatre. Further, the following interacting elements in South African theatre are highlighted: censorship, banning, detention and other restrictions, as well as DET education and religious institutions. Finally, Maponya is introduced, with his political inclinations and his views on art, together with the issue of theatricality in his plays. Chapter two initiates the proposed critical analysis with a focus on The Hungry Earth. The focus is on Theatre of Commitment and the background events that inspired Maponya's response. Chapter three concerns itself with the critical analysis of Jika, "a play about the making of revolutionaries in South Africa ... and serves a political purpose - as a recording of pivotal moment in South African history ... " (Haysom, 1988: 1). An attempt is made to assess the extent to which the playwright has succeeded or failed to strike a chord harmonious with the pronouncements quoted. Chapter four ends the critical analysis with the treatment of Gangsters. Here an observation is made on the fusing of the three personas, namely Rasechaba, Biko and Maponya, into one symbolic whole representing the image of Jesus Christ on the cross - the Saviour who sacrificed His life for the salvation of sinners. Maponya is seen to have sacrificed his time and energy for the liberation of the downtrodden. The conclusion summarizes the study by placing the selected works in their suitable perspective in respect of the notion of Commitment in literature, with particular reference to theatre. Maponya is seen to have played a commendable role in the liberation of his peoples' minds by teaching them the business of organizing revolutions, as well as by championing the liberation struggle.
- Full Text:
- Date Issued: 1998
The child witness in the accusatorial system
- Authors: Müller, Karen, 1964-
- Date: 1998
- Subjects: Child witnesses , Children -- Legal status, laws, etc. , Child witnesses -- South Africa , Evidence (Law)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3715 , http://hdl.handle.net/10962/d1007708 , Child witnesses , Children -- Legal status, laws, etc. , Child witnesses -- South Africa , Evidence (Law)
- Description: For the purpose of this study tbe child witness in the accusatorial system will be viewed as a source of information. When a witness gives evidence in court, the function of the witness is to provide the court with certain information. A number of crucial questions arise when the witness is a child. Do children bave the ability to remember and relate an event accurately? Are children prone to suggestion and fantasy? What effect, if any, does the court environment have on a child 's ability to convey information? What perceptions do children have about the legal process, and how do these perceptions affect their ability to testify? Do adults influence the information which children impart by the techniques they employ to obtain such information? Accepting the hypothesis that child witnesses are sources of information, the purpose of this study is to evaluate all aspects of the criminal justice system relating to child witnesses as well as available research on children to determine whether it is possible to obtain reliable and accurate information from children. Proposals will be formulated regarding the most successful methods of obtaining reliable and accurate information from children, and how these can be adapted for use by the legal system. The purpose of the study is to develop an approach to children in the legal system that will be fair to children while at the same time protecting the rights of the accused, and which will lead to a successful method of obtaining accurate information.
- Full Text:
- Date Issued: 1998
Asymmetric induction in reactions of chiral carboxylic esters and silyl enol ethers
- Authors: Evans, Melanie Daryl
- Date: 1998
- Subjects: Ethers -- Synthesis Esters -- Synthesis Chirality Asymmetric synthesis Organic compounds -- Synthesis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4409 , http://hdl.handle.net/10962/d1006762
- Description: Several camphor and pinane derivatives have been synthesised and evaluated for use as chiral auxiliaries in asymmetric synthesis. Various blocking groups have been attached to the camphor skeleton in attempts to improve stereofacial selectivity; these include α-methoxybenzyl and xylyl groups, and novel stereoisomeric ketal moieties derived from meso- and (R,R)-(-)-2,3-butanediol. Benzylation reactions carried out on the lithium enolates of ester derivatives of the camphor-derived chiral auxiliaries afforded α-benzylated products in 5-60% diastereomeric excess. Stereochemical aspects have been explored using high resolution NMR, X-ray crystallographic and computer modelling techniques, and hydrolysis of selected α-benzylated products has permitted the diasteroselective bias to be confirmed. Opposite configurations at the new stereogenic centre are clearly favoured by the xylyl and ketal blocking groups - an observation rationalised in terms of the presence or absence of chelating potential in the blocking group. Baylis-Hillman reactions carried out on a series of specially prepared camphor-derived acrylic esters containing the ketal blocking group exhibited both low diastereoselectivities (0-30% d.e.) and very long reaction times. Chiral silyl enol ethers, synthesised using both pinane and camphor derivatives as chiral auxiliaries, showed up to 20% diastereomeric excess in MCPBA oxidation, alkylation and Mukaiyama reactions. Attempts to bring the prochiral centre in the silyl enol ether substrates closer to the chiral auxiliary, and thus improve the stereofacial selectivity, proved unsuccessful. The silyl enol ether derivatives, however, display interesting fragmentation patterns in their electron impact mass spectra, which were investigated using a combination of high resolution MS, comparative low resolution MS and metastable peak analysis.
- Full Text:
- Date Issued: 1998
An investigation into the antioxidative potential and regulatory aspects of liver tryptophan 2,3-dioxygenase by tryptophan and related analogues
- Authors: Antunes, Ana Paula Martins
- Date: 1998
- Subjects: Tryptophan -- Physiological effect , Antioxidants , Liver
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4010 , http://hdl.handle.net/10962/d1004070 , Tryptophan -- Physiological effect , Antioxidants , Liver
- Description: The amino acid, tryptophan, obtained through dietary means, is metabolised by the enzymes tryptophan 2,3-dioxygenase (TDO), indoleamine 2,3-dioxygenase (IDO) and tryptophan hydroxylase. All the enzymes have an effect on circulating tryptophan levels, especially TDO, since it is the major site of tryptophan catabolism in the liver and results in the production of kynurenine metabolites, viz. kynurenine, kynurenic acid, 3-hydroxyanthranilic acid and quinolinic acid. Extrahepatically, IDO is responsible for the synthesis of the kynurenine metabolites. Tryptophan 2,3-dioxygenase and IDO activity is increased by hormones or substrates such as tryptophan, and inflammation, in the case of IDO. Tryptophan availability for serotonin (5-HT) synthesis by the enzyme tryptophan hydroxylase is primarily dependent on TDO activity. A study was attempted in order to ascertain whether any of the endogenous metabolites of the kynurenine and serotonergic pathways would be able to inhibit TDO activity. Results showed that although the kynurenines had no effect, the indoleamines, except for the indoleacetic acids, were able to reduce TDO activity. 6-Methoxy-2-benzoxazolinone (6-MBOA), a structural analogue to melatonin, was the most potent inhibitor with a reduction in activity of 55 % compared with the control. The pineal gland in the rat brain has been shown to have the highest IDO activity. With induction, the kynurenine metabolite concentrations of kynurenic acid and quinolinic acid are increased. The effects of both compounds were determined on the serotonergic pathway. Although kynurenic acid produced no significant effect, quinolinic acid significantly reduced N-acetylserotonin and melatonin synthesis at concentrations of lOJLM and 100 JLM respectively. Many authors have implicated oxygen derived species as causative agents in the important neurodegenerative disorders such as Parkinson's and Huntington's disease. Increased radical generation and lipid peroxidation have been suggested to be responsible for the toxic destruction of neurons, especially in the brain because of its high lipid content and oxygen demand. The brain is therefore vulnerable to oxidative attack. During inflammatory diseases, IDO is induced with a resultant increase in kynurenines. This study was also an attempt at determining the effect of kynurenines on lipid peroxidation. All metabolites of the kynurenine pathway were able to induce lipid peroxidation significantly. The antioxidative potential of various tryptophan analogues, viz. serotonin, melatonin and 6-methoxy-2-benzoxazolinone, was determined using quinolinic acid-induced lipid peroxidation. Serotonin, melatonin and 6-MBOA were able to significantly reduce quinolinic acid-induced lipid peroxidation.
- Full Text:
- Date Issued: 1998
Removal and recovery of heavy metals from synthetic solutions and electroplating effluents using yeast and the water fern Azolla filiculoides
- Authors: Zhao, Ming
- Date: 1998
- Subjects: Heavy metals -- Environmental aspects Azolla filiculoides -- Biological control Aquatic weeds -- Biological control Yeast Metal ions Yeast fungi -- Biotechnology Cations
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4001 , http://hdl.handle.net/10962/d1004061
- Description: The aims of the project were twofold. The initial objective of the study, based on previous results, was to develop an economically viable methodology for immobilizing yeast cells for the treatment of heavy metal-laden waste water. The non-viable yeast cross-linked by 13% (w/v) formaldehyde/1N HNO₃ exhibited satisfactory mechanical strength and rigidity in a continuous-flow column operation. No apparent disruption of the biomass after repeated use was observed. The cost of immobilizing 1kg dry yeast pellets was estimated at less than US$I. Zn uptake capacity of FA-cross-linked pellets, on batch trials, remained similar to that of raw yeast, reflecting that the immobilizing procedure did not hinder its metal removing capacity. In column studies, cation metals were effectively removed by the yeast pellets from aqueous solution at natural pHs, and then recovered completely by washing the pellets in situ with O.1M HCl. The recovered metals were concentrated in such small volumes that recycling or precipitation of them was facilitated. The metal uptake capacity of the regenerated biomass remained constant in comparison with cycle 1, indicating that reuse of the yeast would be possible. In the case of Cr⁶⁺, a gradual breakthrough curve of Cr in the column profile was noted, with a simultaneous reduction of Cr⁶⁺ to Cr³⁺. However, Cr⁶⁺ in the effluent can be markedly minimised either by accumulation onto the biomass or reduction to its trivalent form. Desorption of bound Cr⁶⁺ with either alkali or salt could not accomplish the regeneration of the biomass. A combination of reduction and desorption with FA/HNO₃ appeared promising in regeneration of the saturated biomass at 4°C. The metal sorption capacities of the yeast pellets, on a batch or a fixed-bed system are relatively lower than that of documented sorbents. Apparently more of the yeast pellets would be required for treating a certain volume of waste effluent, than with other sorbents. Therefore Azolla filiculoides was examined as a suitable sorbent for this purpose. This constitutes the second part of the project. Azolla filiculoides, a naturally-abundant water fern, was screened for its metal sorption and recovering capacities, mechanical stability, flow-permeability and reusability. The azolla biomass appeared to have fulfilled the required mechanical criteria during the repeated sorption-desorption column operations. It is water-insoluble and appears flexible under pressure when rinsed with water. These characters are of crucial importance in a continuous-flow system since a column can be operated at high flow rates without apparent compact of the biomass and pressure loss. Therefore, immobilization of the biomass can be avoided. The sorption isotherm data, obtained from batch removal of Cr⁶⁺, showed that the sorption process was effective, endothermic and highly pH dependent. Considerable amounts of Cr⁶⁺ were accumulated at the optimum pHs of 2-2.5. Column sorption of Cr⁶⁺ at a low flow rate and pH of 2.5 showed optimum performance with a total Cr uptake of 50.4mg/g at 60% saturation of the biomass. Removal of Cr⁶⁺ from an electroplating effluent using an azolla column was deemed reasonably satisfactory, although the uptake declined slightly. Desorption of bound Cr⁶⁺ with various desorbents was incomplete, which resulted in a low regeneration efficiency of about 50%. However, removal and recovery of Cr³⁺ using the azolla column was than that of Cr⁶⁺. Desorption of Cr³⁺ from the spent biomass column was accomplished with the recovery of 80% using O.5N H₂SO₄, The regeneration efficiencies for Cr³⁺ removal were up to 90% and demonstrated that the biomass is reusable. Cation metal uptake capacities of azolla, obtained either from batch or column experiments, are reasonably high in comparison with other sorbents. The uptake of Ni or Zn ions from solution is pH dependent showing the optimum pH of around 6 to 6.5, under the current experimental conditions. The sorption kinetics for cation metals was rapid with about 80% of the bound Ni ions being taken up in the first 10 min. The character of rapid binding is extremely important in a column sorption process, especially on a large scale since it favours an optimum uptake of metals at high flow rates. The Ni or Zn uptakes in column sorption were not markedly affected when the flow rates were increased from 80mllh up to 800ml/h for the 5g biomass used. The cation heavy metals removed from waste effluents were recovered in a concentrated solution of small volume. The desorption of bound Ni and Zn ions from the saturated biomass was accomplished with either O.2N HCl or H₂SO₄ that resulted in recoveries of more than 95%. The metals recovered, in the case of Ni and Zn, are identical to that of plating agents ego nickel sulphate or chloride, so that recycling of the metals is possible. An effluent-free, closed loop of Ni or Zn treatment system was proposed, whereby the Ni or Zn ions can be recycled to the plating bath whilst the purified water is fed back to the rinse tanks. Ca and Mg ions, commonly present in the electroplating effluents, appeared to affect sorption of heavy metals by azolla when metal concentrations were relatively low, presumedly through its competitive binding for the shared sites on surfaces of azolla. The data obtained from column sorption of Ni and Zn follows the BDST model well, enabling the application of the model to predicting design parameters for scale-up of the biosorption column system. It is interesting that the values of metal uptake, expressed in molar quantities, obtained on respective single-metal solutions and the multiple metal system, are similar, implying that the mechanisms involved in the sorption of all metal cations are similar and that the binding sites on surfaces of azolla are probably shared by all cation metals. The surface of the biomass provides sites for metal binding estimated in the range of 0.45-0.57mmol/g, based on the current experiments. The biomass has a surface area of 429 m²/g and water retention of 14.3 ml/g. The functional groups on the surface of azolla were partially identified using chemical modification and metal binding comparison. Among the functional groups examined, carboxyl groups, provided by amino acids and polysaccharides, appeared to play an important role in metal cation binding. The infrared spectra of the samples support this conclusion.
- Full Text:
- Date Issued: 1998
Human rights: an investigation into the importance of second generation rights
- Authors: Bentley, Kristina Anne
- Date: 1998
- Subjects: Human rights -- Philosophy , Human rights
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2759 , http://hdl.handle.net/10962/d1002969 , Human rights -- Philosophy , Human rights
- Description: This study examines the notion of universal human rights in the context of the importance of social and economic rights for the agency and dignity of human beings. It argues that the recognition of basic rights to what is necessary for physical well-being is essential to any adequate theory of human rights, and that rights of the civil and political variety depend on the recognition of social and economic rights if they are to be exercised. Therefore the secondary status which is usually accorded to social and economic rights results in an imbalanced ideal of human rights both in theory and in practice. This study is an attempt to place second generation rights in their proper context and to argue for them as human rights of equal status and importance. It focuses on the derivation of human rights in general, and shows that second generation rights may be accommodated within this structure. It further supports this position by showing that the categorical differences which are asserted to exist between first and second generation rights are based on a mistaken conception of positive and negative rights and duties, as well as an inadequate conception of liberty. The thesis shows that all rights generate a variety of duties, both positive and negative, and that an adequate theory of rights has to be able to accommodate the inevitability of conflicts of rights at the level of their enforcement. Consequently, this study argues there is no reason to give either class of right primary importance, as both first and second generation human rights are essential to the agency and dignity of a human being, and they are thus interdependent. Furthermore, the thesis shows that human rights can be balanced at the level of the obligations which they generate without compromising the deontological nature of such rights. This thesis argues that a theory of rights which is rooted in the liberal democratic notion of rights, such as that characterised by the choice theory of rights, is inadequate. It therefore argues that a benefit theory of rights must be adopted in order to accommodate conflicts of rights when they arise. The thesis argues that as such conflicts of rights are" most common in cases involving the assertion of social and economic rights, this balancing of rights is of special significance for the enforcement of second generation rights. Furthermore, this thesis argues for a theory of minimal interdependence of first and second generation rights, in order to accommodate the notion of first and second generation rights of equal status and importance, as well as to prevent an inflation of rights claims which would compromise the balancing of rights. It is argued that a reordering of values is necessary to take account of material well-being, as well as civil freedom, as both of these generate fundamental rights of equal status and importance.
- Full Text:
- Date Issued: 1998
The effect of different parameters on the rupture properties of leather in a tensile test
- Authors: Makhothe, Kelebohile
- Date: 1998
- Subjects: Leather -- Testing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5462 , http://hdl.handle.net/10962/d1005247 , Leather -- Testing
- Description: This thesis explores the effect of some parameters on the breaking strain, strength and the shape of the stress-strain curve of bovine leather as revealed by uniaxial tensile tests. The parameters explored are fatliquoring, moisture content, strain rate and cyclic stressing. A basic mechanical model of a simple two-dimensional weave is created and used to describe the effect of such a weave on the shape of the stress-strain curve. It is found that fatliquoring lubricates and opens up the fibre structure and thereby makes the weave more extensible. The increase in the extensibility depends on the direction in which samples are cut and therefore the manner in which the fibres are orientated. Patliquoring is observed to increase the degree to which fibres pull out at break. There are indications that the strength of fatliquored leather decreases with time of storage, while the extensibility increases. The effect of the strain rate on the breaking strain, the tensile strength and the shape of the stress-strain curve is not very clear. The stressing and releasing leather decreases the strength of leather when the fibres are orientated preferentially along the direction of the applied stresses, but has an insignificant effect in the transverse direction. It is concluded that the degree of lubrication in a weave and the orientation of the fibre bundles significantly influence the performance of leather in a test. Both moisture and fatliquoring lubricate the weave. In both the cases the degree of fibre adhesions in a weave is decreased. A well lubricated weave allows its constituent fibres to slide and align along the direction of the applied stresses, and this tends to occur before the fibres themselves areextended. Cyclic testing, at low strains, ruptures fibre adhesions and as a result induces permanent set and makes a hide softer. Most of the work done in breaking the fibre adhesion is done in the first cycle.
- Full Text:
- Date Issued: 1998
The shuttle effect : the development of a model for the prediction of variability in cognitive test performance across the adult life span
- Authors: Jordan, Ann B
- Date: 1998
- Subjects: Cognition -- Age factors Aging -- Psychological aspects Cognition in old age Human information processing -- Age factors Older people -- Psychology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3191 , http://hdl.handle.net/10962/d1008556
- Description: The aim of this thesis was to investigate inter-individual variability on cognitive task performance in normal older adults. In a review of the cognitive aging literature, the implications of a differential perspective were drawn out in order to establish a theoretical and methodological basis for an investigation into variability. A number of regularly occurring patterns, identified on the basis of available reports in the literature, were used to develop a model of variability (the shuttle model). The empirically-based model was located broadly within a neuropsychological framework, and derived explanatory power from the tenets of brain reserve capacity (BRC) theory. It served to describe the bulge in interindividual variability due to aging (the shuttle bulge), and the shifting occurrence of the bulge in relation to the age axis due to cohort and task-related influences (the shuttle shift). A two phase research study was conducted in order to test hypotheses derived from the model. Phase 1 comprised between-groups analyses of normative data covering a broad range of neuropsychological tests in the domains of attention, memory, language, visual and hand motor skills, in order to examine the progression of variability effects across the adult age range. Phase 2 constituted between and within-groups analyses of normative data from a more limited number of neuropsychological tests. It included the examination of raw score distributions and the characteristics of outliers, and was undertaken to explore more closely the nature of the variability phenomena detected in the first phase of the analysis. Taken together, the results of both phases of the investigation revealed statistically significant variability effects in support of the shuttle model. There was a consistent pattern of increased variability in association with older age regardless of functional modality; frequently, in association with later old age, there was also a subsequent decrease in variability (the shuttle bulge). The age of onset of the initial increase in variability occurred earlier or later (the shuttle shift) as a function of four factors: education, gender, task challenge and age-sensitivity of task. The finding of an earlier onset of variability effects for low education, male gender, high task challenge and high age-sensitivity of task was interpreted in terms of BRC threshold theory. The clinical and social implications of the outcome were discussed with special emphasis on the need for a differential perspective on aging, as a complement to the prevailing normative tradition. It was concluded that the shuttle model has considerable heuristic value. It presents an integrative framework for understanding existing variability data and provides clear indications for future research.
- Full Text:
- Date Issued: 1998
The invertebrates of temporary rivers in the Eastern Cape, South Africa
- Authors: Uys, Amanda Cloete
- Date: 1998
- Subjects: Rivers -- South Africa -- Eastern Cape Stream ecology -- South Africa -- Eastern Cape Freshwater invertebrates -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5628 , http://hdl.handle.net/10962/d1004908
- Description: Temporary rivers in dryland regions are subject to highly variable and unpredictable rainfall and flow, and are considered unstable systems relative to perennial rivers of temperate zones. Little is known of the ecology of South Africa's temporary rivers, despite their abundance. The research presented focusses on the aquatic invertebrates inhabiting intermittently-flowing rivers in the 'arid corridor' of the Eastern Cape, South Africa. The major aims of the work were: to investigate which invertebrates inhabit these rivers, how the fauna is affected by environmental variability at various spatial and temporal scales, whether or not a characteristic fauna can be associated with these rivers or the hydrological phases which characterise them, and to establish to what extent faunal overlap occurs between different temporary rivers and between natural and modified temporary and perennial rivers. Research results indicate that the fauna of the Eastern Cape temporary rivers shows little structure at the scales of investigation, and that communities are generally non-equilibrial in character. The major forces shaping the biota are considered to be physical rather than biological, and the most important of these are: present and antecedent hydrological conditions and their duration; time of year; and biotope character, extent and heterogeneity. Three groups of fauna were identified as inhabitants of the temporary rivers: 'residents', 'facultative taxa' and 'opportunist colonists'. Taxa were tentatively allocated to these groups. Faunal resemblance was fairly high in Eastern Cape temporary rivers at the level of family, but not at more detailed taxonomic levels. A comparison between faunas of temporary and perennial rivers in different regions of South Africa illustrated the influence of geographical location on diversity. Within regions, however, there was no indication that perennial rivers were more diverse than intermittent rivers. The relatively high diversities in temporary rivers in this study are attributed at least in part to the heterogeneity in surface water conditions over time. A conceptual framework envisioning a continuum between perennial and temporary rivers is proposed as a basis for ongoing research into these rivers. A supporting terminology for the range of river flow types in South Africa is presented.
- Full Text:
- Date Issued: 1998
Thematic integrity in filmic versions of E.M. Forster's novels
- Authors: Hayes, Kalmia Joy
- Date: 1998
- Subjects: Forster, E. M. (Edward Morgan), 1879-1970. Passage to India , Forster, E. M. (Edward Morgan), 1879-1978. Where Angels Fear To Tread , Forster, E. M. (Edward Morgan), 1879-1978. Howards End , Sturridge, Charles , Merchant Ivory Productions , Lean, David, 1908-1991 , Film adaptations , Motion pictures -- Plots, themes, etc
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2218 , http://hdl.handle.net/10962/d1002261 , Forster, E. M. (Edward Morgan), 1879-1970. Passage to India , Forster, E. M. (Edward Morgan), 1879-1978. Where Angels Fear To Tread , Forster, E. M. (Edward Morgan), 1879-1978. Howards End , Sturridge, Charles , Merchant Ivory Productions , Lean, David, 1908-1991 , Film adaptations , Motion pictures -- Plots, themes, etc
- Description: This study discusses the extent to which Charles Sturridge's Where Angels Fear to Tread, Merchant Ivory's Howards End, and David Lean's A Passage to India have aimed at, and succeeded in, exploring the thematic concerns of E.M. Forster's novels. A brief introductory chapter explains the motivation behind this research, and the choice of critical methodologies used. It concludes with an outline of some of the problems confronting film-makers wishing to explore the concerns of novels. The first chapter, which is devoted to Where Angels Fear to Tread, reveals that while Sturridge is "faithful" to Forster's novel at a superficial level, basing most of his scenes on, and taking most of his dialogue directly from, the text, he does not explore Forster's themes. The facility with which film tells stories proves to be a treacherous trap for Sturridge. His version of Where Angels Fear to Tread is totally vacuous because he failed to develop anything beyond the story -- Forster's "tapeworm" of time (Aspects of the NoyeI41). The causality that Forster calls plot seemed beyond Sturridge's comprehension, leaving his film little more than an endless progression of "and then[s]" (Forster, Aspects 87). Characters are not given their full weight; symbols and leitmotifs are overlooked; the allegorical elements he did recognize, he failed to understand, and thus misplaced, so that the epiphanic moments of the novel are lost. There is no possibility of thematic concerns emerging from a film in which plot, characterization, symbol and rhythm are ignored. Sturridge's apparent inability to understand his source is in stark contrast to Merchant Ivory's sensitivity to Howards End, and their evident familiarity with literary criticism on the work. Chapter two explores the way in which their adaptation smooths out putative flaws in characterization and plot, and uses filmic rhythm and camera work to suggest comments made by the novel's narrator. Almost wholly successful in developing the novel's themes, Merchant Ivory's Howards End does not, however, successfully explore the spiritual dimensions of Forster's novel. Film is a medium capable of great subtlety, but its strength lies in its ability to capture the seen; the unseen tends to evade its grasp. It is in dealing with the unseen that Lean's A Passage to India misses greatness, for in virtually every other respect his version of Forster's masterpiece is superb. Chapter three explores Lean's creative and flexible approach to adaptation, his acute sensitivity to the differing demands of film and novel, and his confident technical mastery. It also explores, however, the emptiness at the heart of his film, an emptiness that is the result of his trivialization of the spiritual concerns of Forster's novel.
- Full Text:
- Date Issued: 1998