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A geographical study of agricultural change since the 1930s in Shixini Location, Gatyana district, Transkei

  • Authors: Andrew, Maura
  • Date: 1992
  • Subjects: Agriculture -- South Africa -- Transkei Land tenure -- South Africa -- Transkei Transkei (South Africa) -- Rural conditions
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:4834 , http://hdl.handle.net/10962/d1005509
  • Description: This study examines the dynamics of agricultural change amongst traditional African smallholder farmers in Shixini location, Gatyana District, Transkei. This entailed an examination of the historical, regional and local causes of agricultural change and the response of the local community. What became evident was that there had been a gradual decline in agricultural output after the 1930s due to a combination of socio-economic and environmental constraints. Pressure on limited resources and land degradation, a consequence of socio-economic pressures on the African peasantry and agricultural expansion, reduced carrying capacities and soil fertility within the African reserves. Racially discriminatory policies also reduced African access to agricultural markets and forced peasants into migrant labour. The initial response to this agricultural decline was to maintain cultivation and pastoral practices, despite declining output, and rely more heavily on migrant labour. However, massive population ~owth from the mid 1950s onwards stimulated a rapid change in cultivation practices. Rural households found it increasingly difficult to gain access to arable land in river valleys and growing poverty undermined their ability to cultivate fields. In response to these conditions the rural population abandoned their fields and expanded garden cultivation. Garden cultivation was a more intensive method of cultivation which made more efficient use of household resources, maintained long-term yields and had a less detrimental impact on the soil. This study attempts to make a contribution to southern African historiography and historical geography. Since the rise of radical human geography in the 1970s there has been a growing number of political economy studies focusing on capitalist expansion, racially discriminatory state policies and associated class conflicts in South Africa. However, most of these studies have focused on urban communities. The political economy of African rural areas has been sorely neglected by human geographers despite the enormous growth of such studies amongst historians and other social scientists. This study of agricultural change in Shixini location, Transkei adds to the small collection of geographical research on the political economy of African rural areas. It also adds to the large body of historical research by focusing on the recent past, a much less well documented period. The most important component of the study was an examination of the response of the rural community to socio-economic and environmental changes. This brought the often neglected role of human agency within the world political economy into the study. Environmental factors, often neglected by'historians and human geographers, were also brought into the analysis. The examination of such a broad range of factors was facilitated through the use of a wide variety of source material including historical, anthropological and socio-economic literature, official statistics, archival records, aerial photographs and a sample survey
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  • Date Issued: 1992

Project water (Grahamstown) : a case study of the development of an environmental education project

Regulation of the indoleamines by sex steroids

  • Authors: Awah, Edmund Kpabi
  • Date: 1992
  • Subjects: Steroids -- Research , Steroid drugs -- Research
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4053 , http://hdl.handle.net/10962/d1004114 , Steroids -- Research , Steroid drugs -- Research
  • Description: Alteration of serum tryptophan leads to parallel alterations in brain tryptophan levels. Such changes in brain tryptophan levels has been shown to lead to mood disturbances. The primary enzyme responsible for altering serum tryptophan levels is the liver cytosolic enzyme, tryptophan pyrrolase. Activation of this enzyme is responsible for the enhanced catabolism of circulating tryptophan. The purpose of the present study was firstly to establish whether there is a link between sex steroids and tryptophan pyrrolase activity especially since sex steroids are also known to cause mood disturbances and secondly to determine the effects of sex steroids on brain indolamine metabolism. The results show that all three sex steroids induce the activity of tryptophan pyrrolase implying that they decrease serum tryptophan levels by the activation of tryptophan pyrrolase, thus making less tryptophan available for uptake by the brain. It was also shown that the sex steroids enhance the uptake of ¹⁴C-tryptophan by brain synatopsomes. In addition, the sex steroids influenced the pattern of metabolism of serotonin by organ cultures of rat pineal glands. It is possible that the sex steroids regulate the availability and uptake of indoleamines in the brain.
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  • Date Issued: 1992

The role of the teachers' centre in the professional development and in-service training of teachers with specific reference to the East London Teachers' Centre

  • Authors: Badenhorst, John Henry
  • Date: 1992
  • Subjects: Teachers -- In-service training -- South Africa , Education -- South Africa -- East London , Professional education -- South Africa , Educational change -- South Africa
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1755 , http://hdl.handle.net/10962/d1003639 , Teachers -- In-service training -- South Africa , Education -- South Africa -- East London , Professional education -- South Africa , Educational change -- South Africa
  • Description: Teachers' Centres are one of the means whereby teachers needs for in-service education and training (Inset) can be met. The professional basis of Teachers' Centres as providers of in-service education and training derives from the need of teachers to develop professionally throughout their careers. Aspects which need to be considered are the need for professional growth and the professional nature of teaching. The effective provision of in-service training requires a knowledge of effective in-service training practise and the barriers that could be encountered in presenting it. Central to any Inset for teachers would be the teachers' needs for such activity. Following on a general statement of teachers needs for Inset the role of the Teachers' Centre in meeting these needs will be examined. Teachers' Centres have specific advantages in meeting certain areas of need for Inset by teachers. A knowledge of the professional activities of teachers activity and methods of establishing the needs for Inset of teachers should promote the effective provision of these programmes. The teacher as an adult learner is important to effective Teachers' Centre operation and the nature of adult learning and variables which affect it will determine the Teachers' Centre reaction in providing Inset. Subject study group activity is very important in Teachers' Centres in the Cape Province and the principles involved in their operation together with practical considerations regarding their operation are important in the provision of Inset. The practical application of theory is illustrated by examples from the East London Teachers' Centre with an emphasis on organisation and the creation of a climate within the Centre for the existence of study groups. The presentation methods used in these study group activities are important and will vary according to the needs of the study group. The selection of methods together with the organisation of presentations and practical methods used in presentation will have an important effect on how they operate. Teachers' Centres have a role to play in promoting change and innovation in schools. The theories of promoting innovation and the roles of the change agent are important. Practical examples from the East London Teachers' Centre are provided. This research, thus, provides a theoretical study of the role of Teachers' Centres in meeting some of the inset needs of teachers as well as practical examples of such activities.
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  • Date Issued: 1992

Neuropharmacological interactions in the rat pineal gland a study of antidepressant drugs

  • Authors: Banoo, Shabir
  • Date: 1992
  • Subjects: Antidepressants -- Research , Pineal gland -- Research
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3744 , http://hdl.handle.net/10962/d1003222 , Antidepressants -- Research , Pineal gland -- Research
  • Description: The rat pineal gland provides a convenient model for investigating nor adrenergic receptor neurotransmission and the effects of various drugs on these processes in health and disease. The effect of a variety of antidepressant drugs on rat pineal gland function following acute and chronic administration is described. Antidepressants from several different classes increase melatonin synthesis in rat pineal gland cultures when administered acutely. This effect appears to be mediated by noradrenaline acting on postsynaptic β-adrenoceptors. Activation of these receptors, in turn, activates the enzyme serotonin N-acetyltransferase via a cyclic adenosine monophosphate (cAMP) second messenger system. Serotonin N-acetyltransferase catalyses the rate-limiting conversion of serotonin to melatonin. Blockade of postsynaptic β-adrenoceptors prevents the antidepressant-induced increase in melatonin synthesis. The possibility that atypical antidepressants as well as those that selectively inhibit serotonin reuptake may increase melatonin synthesis via a β-adrenoceptor mechanism is discussed. In contrast, however, antidepressants from different classes have variable effects on rat pineal gland function when administered repeatedly. Chronic treatment with antidepressants that selectively inhibit noradrenaline reuptake appear to down-regulate the β-adrenoceptor system while, simultaneously, increasing melatonin output. Atypical antidepressants and those that selectively inhibit serotonin reuptake appear to be without these effects when administered repeatedly. The pineal gland of normal rats may therefore not represent a suitable model for evaluating the biochemical effects of chronic antidepressant treatment. In an attempt to investigatc pineal gland function in rats with "model depression" , antidepressants were administered to chronically reserpinized rats. Treatment with reserpine produced an increase in the density of pineal β-adrenoceptors. In addition, pineal cyclic AMP accumulation and N-acetyltransferase activity were increased in reserpinized rats following exogenous catecholamine stimulation. Reserpine, by depleting intraneuronal catecholamine stores, prevented the nocturnal induction of N-acetyltransferase activity and reduced the synthesis of melatonin in pineal gland cultures. A variety of antidepressants, irrespective of their acute pharmacological actions, reversed these effects when administered chronically to resepinized rats. Acute antidepressant administration was not associated with a reversal of the reserpine-induced effects. These findings provide additional evidence against the hypothesis that antidepressant drugs act by reducing noradrenergic neurotransmission and casts doubt on the importance of β-adrenoceptor down-regulation in the mechanism of antidepressant action. The possibility that the pineal gland of the reserpinized rat may represent an alternative model for evaluating antidepressant therapies is discussed.
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  • Date Issued: 1992

A study of the role of nature conservation law enforcement officers as facilitators of environmental education

  • Authors: Barrett, Janice Anne
  • Date: 1992
  • Subjects: Environmental education Nature conservation
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1783 , http://hdl.handle.net/10962/d1003668
  • Description: This study explores the potential roles of a sample of 18 nature conservation law enforcement officers, as facilitators of environmental education. More specifically it examines their attitudes towards their dual duties of enforcing laws and providing extension services. Attitudes were examined by means of qualitative data analysis from semi-structured interviews. Officers' environmental attitudes, as well the relative emphasis placed on law enforcement and extension, and their own perspectives of working with communities, are explored. The historical and cultural context of officers' work, as well as worldviews and personality traits are also discussed. Certain recommendations regarding officers' roles as facilitors of environmental education are made.
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  • Date Issued: 1992

Educational computing in secondary schools of the Cape Education Department: a research survey to assess computing facility acquisition and its utilization

  • Authors: Bean, Pat
  • Date: 1992
  • Subjects: Education, Secondary -- South Africa -- Data processing Education, Secondary -- South Africa -- Computer network resources Computer-assisted instruction -- South Africa
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1505 , http://hdl.handle.net/10962/d1003387
  • Description: Secondary schools under the jurisdiction of the Cape Education Department (CED) have, over the past 10 years, been acquiring computer equipment without a national policy on educational computing in South Africa, and within only broad parameters provided by their department. The aim of this study was to determine the present status of educational computing in these schools. A literature survey on educational computing was undertaken and a number of international and local 'computers-in-schools' initiatives were elucidated. A field survey, involving all CED secondary schools (239), was initiated by sending questionnaires to principals of these schools - a return rate of 89% was achieved. The results of the research revealed that most CED secondary schools have already acquired computer facilities. The role of pressure groups such as teachers, parents, business sector etc together with other factors that might have influenced schools in acquiring their computer facilities was also investigated. The investigation also revealed where and how these facilities are being utilised: most schools use their computers for administrative functions, with the computer-as-a-tool for teachers and pupils also fast gaining ground. Computer-assisted learning activities, where the computer is integrated with subject curricula, are however still limited. The extent of both teachers' formal training in educational computing and their familiarity with different software applications were also determined. Schools were also required to indicate the areas where they experience problems in getting teachers and pupils more involved in 'computers-in-education' activities. The present educational computing position in secondary schools of the CED will have to serve as a foundation for the department's CISR Project embarked upon in 1991.
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  • Date Issued: 1992

The university and a free society

  • Authors: Bengu, S M E
  • Date: 1992
  • Subjects: Academic Freedom -- South Africa
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/662 , vital:19979
  • Description: Has the clamour for University autonomy and academic freedom in our country not served to legitimize repression in the hands of a narrow, undemocratic “oligarchy”? Has the narrow understanding of academic freedom and university autonomy excluded the freedom of individuals and groups such as women, black communities, students, and non-academics? Before we consider the relationship that will, hope fully, exist between universities and a free society that is going to emerge in this country, we ought to accept the fact that university autonomy and academic freedom are hollow in an oppressed society such as we still have in our country.
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  • Date Issued: 1992

Selecting educational computer software and evaluating its use, with special reference to biology education

  • Authors: Beyers, Ronald Noel
  • Date: 1992
  • Subjects: Biology -- Study and teaching -- Computer programs Education -- Data processing Biology -- Computer-assisted instruction
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1764 , http://hdl.handle.net/10962/d1003649
  • Description: In the field of Biology there is a reasonable amount of software available for educational use but in the researcher's experience there are few teachers who take the computer into the classroom/laboratory, Teachers will make use of video machines and tape recorders quite happily, but a computer is a piece of apparatus which they are not prepared to use in the classroom/laboratory. This thesis is an attempt to devise an educational package, consisting of a Selection Form and an Evaluation Form, which can be used by teachers to select and evaluate educational software in the field of Biology. The forms were designed specifically for teachers to use in preparation of a computer lesson. The evaluation package also provides the teacher with a means of identifying whether the lesson has achieved its objectives or not. The teacher may also be provided with feedback about the lesson. The data is gathered by means of a questionnaire which the pupils complete. It would appear that teachers are uncertain as regards the purchase of software for their subject from the many catalogues that are available. The evaluation package implemented in this research can be regarded as the beginnings of a data base for the accumulation of information to assist teachers with details on which software to select. Evidence is provided in this thesis for the practical application of the Selection and Evaluation Forms, using Biology software.
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  • Date Issued: 1992

" Past the wit of Man": A Midsummer Night's Dream's debt to Praise of Folly

  • Authors: Birkinshaw, Catherine
  • Date: 1992
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/457711 , vital:75672 , https://hdl.handle.net/10520/AJA1011582X_129
  • Description: There have been several attempts to explore Shakespeare's debt to Erasmus, notably Waiter Kaiser's in Praisers of Folly (1964), which concentrates on the figure of Falstaff. But on account of the Christian-Classical tradition both writers share, and on account also of Erasmus's widespread influence in the sixteenth century, direct borrowing is generally hard or impossible to prove.
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  • Date Issued: 1992

The geology and evaluation of the "A"-reef at No.3 shaft, Western Holdings Mine, Welkom goldfield

  • Authors: Blamey, Nigel John Frederick
  • Date: 1992
  • Subjects: Gold mines and mining -- South Africa -- Free State , Gold ores -- Geology -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4957 , http://hdl.handle.net/10962/d1005569 , Gold mines and mining -- South Africa -- Free State , Gold ores -- Geology -- South Africa
  • Description: The "A" -Reef occurs within the Aandenk Formation of the Central Rand Group, Witwatersrand Supergroup, in the Welkom Goldfield. It comprises the Witpan and Uitsig Reefs which are both oligomictic conglomerates, and are exploited for their gold content by Anglo American Corporation. The main Witpan channel complex is orientated in a NW-SE direction and occurs close to No.3 Shaft of Western Holdings Mine where it is currently being mined. The Witpan Reef varies in thickness from 7-220cm, with lateral facies changes controlling the thickness. Within the reef, gold is associated with degradation surfaces, carbonaceous material, increase in pebble sphericity, and channel edges. Two channel edges have yielded the best gold values on No.3 Shaft although the potential for further payable gold lies in the recognition of sieve conditions. The potential also exists for extensions of the "carbon"-bearing Uitsig channel currently being mined on President Steyn Mine. The palaeo-environment proposed for formation of the Witpan Reef is a braidplain that was partly reworked by a brief transgression. Ore evaluation using geostatistics was considered a valid technique as the dataset is sufficiently well structured. Semi-variograms in the channel and across-channel directions differ markedly. It was found that variograms of gold in cmg/t lacked sufficient structure for modelling, however, log semi-variogram modelling followed by simple log-kriging and back-transformation, proved to be the most successful method. Owing to the morphology and distribution of gold within the reef, a geologically based geostatistical valuation method is proposed. The potential for further exploration of "A" -Reef depends on a substantially higher gold price. In this event, exploration of Uitsig Reef to the southwest of the current mining area is recommended as well as a new exploration strategy for Witpan Reef.
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  • Date Issued: 1992

Fieldwork as a compensatory teaching strategy for rural black senior secondary schools

  • Authors: Boqwana, Eleanor Pindiwe
  • Date: 1992
  • Subjects: Black people -- Education -- South Africa , Geography -- Fieldwork -- Study and teaching , Geography -- Study and teaching -- South Africa
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1544 , http://hdl.handle.net/10962/d1003426 , Black people -- Education -- South Africa , Geography -- Fieldwork -- Study and teaching , Geography -- Study and teaching -- South Africa
  • Description: The understanding of geographical concepts and the development of skills requires the use of appropriate teaching strategies. Modern school syllabuses emphasize the development of concepts and skills which are basic to the understanding of geography. Geography provides practical learning opportunities which directly involve the learner. Techniques which directly involve the learner are perceived to be the most valuable. Fieldwork, which embraces a wide range of innovative teaching strategies, is the one best suited to give first-hand experience to the pupils. This study investigates the potential of fieldwork to promote conceptual understanding in geography with special reference to pupils in rural schools. Extensive literature on fieldwork in geographical education was analysed. Surveys of geography teachers and pupils in senior secondary schools were conducted to assess their attitudes towards geography and the use of learner-centred approaches with special reference to fieldwork. The role of fieldwork to promote conceptual understanding was evaluated by exposing two groups of pupils to different field activities. This revealed that fieldwork promotes understanding, stimulates interest and builds up confidence even when first introduced at senior secondary level.
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  • Date Issued: 1992

The effect of pineapple cultivation on factors influencing soil erodibility in the Eastern Cape, South Africa

  • Authors: Boucher, Kim Gillian
  • Date: 1992
  • Subjects: Soil erosion -- South Africa Pineapple industry -- South Africa -- Eastern Cape Agriculture -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4827 , http://hdl.handle.net/10962/d1005502
  • Description: The study examines the effect of ridged pineapple cultivation on factors influencing the soil erodibility of Glenrosa and Oakleaf soil forms in the Bathurst district of South Africa. A number of physical and chemical variables influencing soil erodibility are investigated, namely soil moisture, bulk density, porosity, infiltration rate, aggregate stability, shear strength, soil texture, soil structure, penetrability, organic carbon, pH and cation exchange capacity. These soil characteristics are examined in undisturbed soils under natural vegetation and compared to those on adjacent traffic areas, pineapple ridges and pineapple furrows. The results of the analyses between the four sample sites indicate that ridged cultivation of pineapples has a negative effect on factors influencing soil erodibility on the areas studied. The results of the analysis within each of the sample sites do not illustrate any clear relationships and thus depict the complexity and multiplicity of the soil erodibility phenomenon. A further study, augmenting the soil erodibility data with actual soil loss data, is recommended
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  • Date Issued: 1992

In search of home : Hillman's archetypal perspective on the therapeutic process of an adult patient

  • Authors: Bradley, Margaret Antoinette
  • Date: 1992
  • Subjects: Hillman, James , Archetype (Psychology) , Psychotherapy -- Case studies
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3127 , http://hdl.handle.net/10962/d1006290 , Hillman, James , Archetype (Psychology) , Psychotherapy -- Case studies
  • Description: The case study method was used to trace the therapeutic process of a 23 year old woman, over a period of 12 sessions. The focus of the study was her issue with abandonment which emerged as the central theme in therapy. Hillman's archetypal approach was used as a framework in understanding the process and resolution of her feelings of abandonment. According to Hillman, the therapy process activates the archetypal abandoned child. For a successful therapeutic outcome the process of de-literalisation must occur in order for the patient to move from literal acting out to symbolic containment. Core moments in the therapeutic process were used, together with an interpretation from Hillman's approach, to illustrate the various themes around the issue of abandonment. The present case study illustrates how the theory in area was relevant in practice with this particular case.
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  • Date Issued: 1992

In vitro effects of three organic calcium channel blockers on the rat pineal gland

  • Authors: Brown, Clint
  • Date: 1992
  • Subjects: Calcium -- Antagonists , Pineal gland -- Research
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:3745 , http://hdl.handle.net/10962/d1003223 , Calcium -- Antagonists , Pineal gland -- Research
  • Description: The calcium signal has emerged as an imponant component of intracellular regulation. Pineal function was thought to be slowed by the prominent calcification seen with increasing age, but recently it has been shown that calcium plays a crucial role in the adrenergic regulation of the gland. Beta-adrenoceptor stimulation increases melatonin (aMT) synthesis by increasing the activity of cyclic 3 '-5' adenosine mono phosphate (cAMP). Cyclic-AMP regulates the production of the pineal hormone, melatonin, from serotonin via the rate-limiting enzyme N-acetyltransferase (NAT). Increased intracellular cAMP is essential to the adrenergic induction of NAT. Noradrenaline(NA)also elevates pinealocyte cyclic guanosine monophosphate (cGMP). Adrenergic regulation of these cyclic nucleotides involves both α₁ - and β-adrenoceptors. Beta-adrenoceptor stimulation is an absolute requirement. Alphal-adrenoceptor activation, which is ineffective alone, serves to amplify the β-stimulated cAMP and cGMP responses via a positive effect on a Ca²⁺⁻/ phospholipiddependent protein kinase (Protein kinase-C) and a net influx of Ca²⁺ into the pinealocyte. Previous studies suggest the use of organic calcium channel blockers (CCBs) as probes of calcium-mediated processes. Applying this concept, the study set out to investigate the influence of a representative of each of the structurally diverse groups of calcium channel blockers viz. verapamil, diltiazem and nifedipine, and to examine their effect on β-adrenoceptor stimulation. It used the β-agonist isoprenaline (ISO) and the mixed [α₁/β]agonist noradrenaline (NA), for its combined [α₁/β]adrenoceptor stimulation, on agonist-induced increases in the production of radio-labelled aMT and N-acetylserotonin(aHT) -measured as the sum of N-acetylated product- from [¹⁴C] serotonin. This was done using organ cultures of rat pineal glands. It was speciously assumed that this drug paradigm would allow the determination of Ca²⁺ influx and/or the blocking thereof in the reported potentiation by using ISO as a non Ca²⁺ -entry stimulating agonist, compared with NA and its Ca²⁺ -entry stimulating properties. Surprisingly, all 3 CCB's potentiated the effect of NA. Only diltiazem was found not to potentiate the effect of ISO. In an attempt to uncover the reason for these results, the study moved toward a mechanistic approach,focusing in an antecedent manner on the various steps in the indole metabolic pathway to identify the point at which the change occurred, and hence possibly elucidate the mechanism responsible for the paradoxical increase. Experiments which assayed the levels of NAT, under the same drug conditions, showed the paradoxical increase to be already evident at this stage. Secondary experiments confirmed that NA stimulation of the pineal is dependent on Ca²⁺, both in organ culture and with NAT: the Ca²⁺ chelator EGTA abolished adrenergically-induced stimulation, while Ca²⁺ added after EGTA, restored the enzyme activity. The ionophore A23187 (which is able to transport Ca²⁺ directly into the pinealocyte via a mechanism which differs from the α₁ - mechanism) when used in conjunction with ISO or NA, was able to potentiate the responses of these two agonists relative to control values (agonist-alone), but by itself had no effect. With the enzyme NAT critically dependent upon cAMP for its induction, it was decided to determine the levels of cAMP and then those of its regulator, cAMP-phosphodiesterase (cAMP-PDE). This reasoning was prompted by reports of anti-calmodulin activity shown by the CCBs, in addition to their channel blocking effects. By binding to calmodulin (CaM), the CCBs are reportedly able to inhibit the CaM-dependent activation of cAMP-PDE. Following NA stimulation, verapamil caused a significant decrease in cAMP-PDE levels and an increase in cAMP. The other CCBs showed a similar trend. Glands stimulated with ISO in the presence of verapamil and nifedipine showed no significant differences in cAMP or cAMP-PDE levels. Diltiazem, however, was found to decrease the effect of ISO on cAMP while causing a concomitant increase in cAMP-PDE. This i) supported a possible hypothesis that the observed enhancement is a result of cAMP levels remaining elevated due to an inhibition of cAMP-PDE by the CCEs and ii) pointed to the possible presence of a CaM-sensitive PDE within the rat pineal gland. To test this hypothesis, two drugs which are more specific in their actions on CaM effects were chosen to see if the earlier results could be mimicked and thereby confirmed. Glands stimulated with NA in the presence of the specific CaM inhibitor R 24571 showed increased NAT activity and [¹⁴C]-aMT production. cAMP-PDE levels were clearly down, thus corroborating the possibility of cAMP-PDE inhibition. Glands incubated in the presence of M&B 22948, a CaM-sensitive PDE inhibitor, showed similar increases in NAT activity and [¹⁴C]-aMT. These findings therefore support the initial results and although indirect, confirm the hypothesis that the paradoxical increase following predominantly NA stimulation could be a result of cAMP levels remaining elevated, due to inhibition by the CCEs of the CaM-dependent activation of its regulator cAMP-PDE. In summary, data presented herein concur with proposals that: i) the CCEs are not specific enough to be used as tools to research Ca²⁺ -mediated events, as they appear to have sites of action other than the voltage operated channel (VOC); eg. binding to calmodulin, ii) there are functional differences between the CCEs as shown by diltiazem in this series of experiments, iii) there is a CaM-sensitive-PDE present in the pineal.
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  • Date Issued: 1992

A polarimetric method for collagenase activity measurement

  • Authors: Brüning, Adrian Rudolf Nicolaus Ernst
  • Date: 1992
  • Subjects: Collagenases -- Research , Hides and skins -- Preservation -- Research
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4052 , http://hdl.handle.net/10962/d1004113 , Collagenases -- Research , Hides and skins -- Preservation -- Research
  • Description: A polarimetric method for monitoring the rate of soluble collagen breakdown by collagenase enzyme action has been developed. The method represents an extension of previous physicochemical techniques based on viscometry, but is simpler and easier to carry out, particularly in the case of reaction rate studies. The method was developed arising from reports of collagenase activity measurement on inappropriate substrates such as gelatin, modified collagens and synthetic polypeptides. The optical method depends on measurement of the loss in optical rotation in solutions of soluble calfskin collagen resulting from initial enzymic cleavage of the collagen trip1e-helix, followed by spontaneous unwinding of the resultant unstable helical fragments. Specific assay conditions were chosen to ensure that the loss in optical rotation following enzymic cleavage was rapid and complete. The method is specific since in the absence of collagenase, non-specific proteinases produce only a limited decrease in solution optical activity. The method has also been compared with established physicochemical assay techniques and compares favourably with both viscometric and titrimetric collagenase assays. The availability of a rapid, sensitive and quantitative procedure for measurement of collagenase activity provides a convenient means for detecting the presence of collagenase in solution and examination of hide bacterial cultures for collagenase production. In addition, a study of biocidal compounds of potential interest in hide preservation for possible inhibitory effects on collagenase is conveniently carried out with the method. Fundamental research into synergistic action in enzymic hydrolysis of collagen is now possible, providing valuable insight into the mechanism of raw hide biodeterioration.
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  • Date Issued: 1992

Fuzzy uniform spaces

  • Authors: Burton, Michael Howard
  • Date: 1992
  • Subjects: Fuzzy sets -- Research Uniform spaces -- Research
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5408 , http://hdl.handle.net/10962/d1005222
  • Description: For a fuzzy uniform space, the notion of a Cauchy prefilter, a precompact fuzzy set, a complete fuzzy set and a bounded fuzzy set are defined in such a way that these notions are good extensions of the corresponding notions for a uniform space. A theory of fuzzy uniform spaces is developed which generalises the theory of uniform spaces.
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  • Date Issued: 1992

Public relations in community work : a public relations programme for direct service organisations

  • Authors: Carmichael-Kathan, Averil Margaret
  • Date: 1992 , 2012-11-28
  • Subjects: Social service -- Public relations -- Research , Community organization -- Research , Social service -- Research
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:692 , http://hdl.handle.net/10962/d1006375 , Social service -- Public relations -- Research , Community organization -- Research , Social service -- Research
  • Description: The community work method of social work is a method requiring creativity, application of specialised skills and knowledge, sound planning and administration and a persuasiveness to reach the various sectors of the community in order to accomplish broad based goals. Public relations is an occupation that has a sound body of literature and theory, a code of ethics or conduct, a host of tools and methods and also requires sound planning and administration, bound together with persuasiveness to reach the various publics in order to accomplish goals affecting image, quality of service rendering and marketing of services. The present study was concerned with identifying the commonalities and the differences between the profession of community work and the occupation of public relations in order to enhance the content of community work theory for practical application by community workers. The differences between the two would, in fact, teach content to community work. It was hypothesised that public relations has a necessary function and is an occupation that can be internalised with and applied to community work for the effective marketing of organisational services. A model for incorporating public relations into community work was designed and implemented in a direct service welfare organisation with positive results. This design is applicable to other direct service welfare organisations with innovative and flexible management teams. The results of an empirical research study, making use of random sampling and questionnaires, was analysed. The results indicated that public relations and community work were comparable entities with reference to knowledge bases, values, skills, tools, methods, techniques, ethics and programmes. A third group of respondents emerged in this study - community workers practising public relations firmly within the realm of community work. This group advocated the use of marketing and communication strategies in applying the community work method effectively. The primary difference to emerge from the work research was one of emphasis in applying methods and subsequently, community work can learn a great deal from these differences which will enhance service rendering correspondingly. The culmination of this study led to several highly relevant conclusions and recommendations for welfare organisations in a Post-apartheid South Africa. The most worthwhile conclusion was that community work has a great deal to learn from public relations, and that they are combinable entities at every level. , KMBT_223
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  • Date Issued: 1992

The tonology of Xhosa

  • Authors: Claughton, John Sellick
  • Date: 1992
  • Subjects: Xhosa language -- Tone
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3596 , http://hdl.handle.net/10962/d1002171
  • Description: This thesis is an examination of the tonology of Xhosa. After an initial survey of the surface tones of the language, and a review of previous studies of Xhosa tone, a description is given of the major tonal patterns of Xhosa noun and verb morphology. In the course of this description the major tonologica1 rules are allowed to emerge. In particular it is shown that some of these rules lead to complex patterns of variation in the pronunciation of the same individual. The derivation of the tone patterns of adjectives and relatives is discussed and it is shown that these tone patterns offer partial support for the derivation of some adjective and relative constructions as derived from embedded sentences but also support for deriving simple attributive adjective constructions by means of phrase structure rules. Some interesting tonal patterns such as that shown by reduplicated stems are then explored. The tones of loan words are then investigated and evidence for the identification of English and Afrikaans stress with high tones by Xhosa speakers is adduced. In the final chapter certain general problems of Xhosa tone are discussed. In particular it is argued that attempts to interpret the tonal system in terms of an accent are unrevealing and also it is suggested that attempts to unify the various rules that spread tones to the right are mistaken. In the appendices a comprehensive survey of the tones of Xhosa inflections is given together with a substantial list of Xhosa words with the tones marked.
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  • Date Issued: 1992

Domestic strategies of rural Transkeian women

  • Authors: Cloete, Laura
  • Date: 1992
  • Subjects: Rural families -- South Africa -- Transkei Women -- South Africa -- Transkei Women -- South Africa Sex role -- South Africa -- Transkei Rural women -- South Africa -- Transkei Transkei (South Africa) -- Social conditions Transkei (South Africa) -- Rural conditions Transkei (South Africa) -- Economic conditions
  • Language: English
  • Type: Book , Text
  • Identifier: http://hdl.handle.net/10962/2014 , vital:20247 , ISBN 0868102342
  • Description: This research, originally undertaken as part of a B.A.(Honours) Degree in Anthropology, has several aims. Firstly, it aims to reveal the various community options available to women in rural Transkei for coping with their domestic activities in the face of the large-scale absence of men. It will analyse the rationale behind the choices and their consequences for the women’s workload. Secondly, this will illuminate gender and generational roles and attitudes of community members, present and absent, in the community. The focus, in this case, will be predominantly on women, however. Thirdly, and finally, this research will analyse the relationships of power between men and women, and between adults and children by examining the various influences, such as religion and education, which constrain and coerce their behaviour and attitudes. From this, we should be left with an illuminating picture of the forces under which women operate in rural Transkei; and with some insight into their behaviour and attitudes, their beliefs and aspirations and into their lives. , Digitised by Rhodes University Library on behalf of the Institute of Social and Economic Research (ISER)
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  • Date Issued: 1992
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