The demography, breeding biology and management of two mullet species (Pisces : Mugilidae) in the Eastern Cape, South Africa
- Authors: Bok, Anton
- Date: 1984
- Subjects: Fishes -- South Africa -- Eastern Cape Mullidae -- South Africa -- Eastern Cape Estuarine ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5213 , http://hdl.handle.net/10962/d1004931
- Description: Aspects of the life history of Myxus capensis which were likely to be most affected by man-induced habitat changes, were studied in the eastern Cape. Myxus capensis was found to be specialized for a catadromous life history. The fry migrate into freshwater reaches of rivers within a few months of being spawned at sea and return to an estuarine or marine environment when maximum size has been attained and large energy reserves necessary for spawning have been accumulated. Myxus capensis penetrates considerable distances up eastern Cape rivers and although present in the upper reaches of some estuaries, is only common in freshwater-dominated systems. Myxus capensis has adapted its life history style in a number of ways to overcome the constraints associated with the spatial separation of the freshwater feeding areas and the marine spawning grounds in a region prone to droughts and erratic river flow. Research on the more estuarine-dependent Mugil cephalus, which is also found in the freshwater reaches of eastern Cape rivers, enabled useful comparisons to be drawn. As the latter species is not dependent on a freshwater phase in its life cycle, it is subject to different selection pressures. This comparative approach gave insights into the adaptive significance of the life history tactics of Myxus capensis. Myxus capensis displays a number of life history tactics characteristic of migratory fish species which are thought to increase population fecundity by increasing the number of large females and hence maximizing egg production. These include a sex ratio in favour of females, faster female growth, females remaining longer in the freshwater feeding areas and reaching a larger ultimate size. Possible adaptations to the periodic isolation of the feeding and spawning areas include: (i) the development of ripe gonads only in estuarine or marine areas when access to the spawning grounds is ensured; (ii) year-round spawning and hence recruitment which enables the erratic floods to be used at any time for downriver spawning migrations and reduces the chances of total recruitment failure due to short-term adverse environmental conditions and (iii) a relatively wide range of size and age at first (and final) sexual maturity (2+ to 5+ years); this tends to ensure successful reproduction and recruitment in spite of a series of poor years, as well as dampen population fluctuations after long periods of isolation in fresh water. The dependence of Myxus capensis on the freshwater reaches of eastern Cape rivers makes this species vulnerable to man-induced habitat changes. The erection of barriers to migration has cut off large stretches of suitable habitat and almost completely eliminated Myxus capensis from certain rivers. This detrimental effect has been largely responsible for the recent inclusion of this species on the Red Data list of endangered fish species in South Africa. This study demonstrated the considerable fisheries potential of both mullet species and this should ensure that their conservation and wise utilization be given high priority. Management proposals include: (i) the netting and lifting of Myxus capensis over barriers to migration; (ii) the construction of fish ladders when feasible and (iii) the artificial propagation of this species to enable large-scale stockings of existing man-made impoundments as well as natural habitats to be carried out. It is predicted that the life history characteristics of Myxus capensis, which evolved in response to an erratic freshwater environment, should ensure that when man-induced habitat changes are rectified, this species will again flourish in eastern Cape rivers.
- Full Text:
- Date Issued: 1984
- Authors: Bok, Anton
- Date: 1984
- Subjects: Fishes -- South Africa -- Eastern Cape Mullidae -- South Africa -- Eastern Cape Estuarine ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5213 , http://hdl.handle.net/10962/d1004931
- Description: Aspects of the life history of Myxus capensis which were likely to be most affected by man-induced habitat changes, were studied in the eastern Cape. Myxus capensis was found to be specialized for a catadromous life history. The fry migrate into freshwater reaches of rivers within a few months of being spawned at sea and return to an estuarine or marine environment when maximum size has been attained and large energy reserves necessary for spawning have been accumulated. Myxus capensis penetrates considerable distances up eastern Cape rivers and although present in the upper reaches of some estuaries, is only common in freshwater-dominated systems. Myxus capensis has adapted its life history style in a number of ways to overcome the constraints associated with the spatial separation of the freshwater feeding areas and the marine spawning grounds in a region prone to droughts and erratic river flow. Research on the more estuarine-dependent Mugil cephalus, which is also found in the freshwater reaches of eastern Cape rivers, enabled useful comparisons to be drawn. As the latter species is not dependent on a freshwater phase in its life cycle, it is subject to different selection pressures. This comparative approach gave insights into the adaptive significance of the life history tactics of Myxus capensis. Myxus capensis displays a number of life history tactics characteristic of migratory fish species which are thought to increase population fecundity by increasing the number of large females and hence maximizing egg production. These include a sex ratio in favour of females, faster female growth, females remaining longer in the freshwater feeding areas and reaching a larger ultimate size. Possible adaptations to the periodic isolation of the feeding and spawning areas include: (i) the development of ripe gonads only in estuarine or marine areas when access to the spawning grounds is ensured; (ii) year-round spawning and hence recruitment which enables the erratic floods to be used at any time for downriver spawning migrations and reduces the chances of total recruitment failure due to short-term adverse environmental conditions and (iii) a relatively wide range of size and age at first (and final) sexual maturity (2+ to 5+ years); this tends to ensure successful reproduction and recruitment in spite of a series of poor years, as well as dampen population fluctuations after long periods of isolation in fresh water. The dependence of Myxus capensis on the freshwater reaches of eastern Cape rivers makes this species vulnerable to man-induced habitat changes. The erection of barriers to migration has cut off large stretches of suitable habitat and almost completely eliminated Myxus capensis from certain rivers. This detrimental effect has been largely responsible for the recent inclusion of this species on the Red Data list of endangered fish species in South Africa. This study demonstrated the considerable fisheries potential of both mullet species and this should ensure that their conservation and wise utilization be given high priority. Management proposals include: (i) the netting and lifting of Myxus capensis over barriers to migration; (ii) the construction of fish ladders when feasible and (iii) the artificial propagation of this species to enable large-scale stockings of existing man-made impoundments as well as natural habitats to be carried out. It is predicted that the life history characteristics of Myxus capensis, which evolved in response to an erratic freshwater environment, should ensure that when man-induced habitat changes are rectified, this species will again flourish in eastern Cape rivers.
- Full Text:
- Date Issued: 1984
The demography, spatial ecology and reproductive success of the black rhinoceros, Diceros bicornis, in Hluhluwe-iMfolozi Park, Kwazulu-Natal, South Africa
- Authors: Nhleko, Zoliswa Nombulelo
- Date: 2014
- Subjects: Hluhluwe-iMfolozi Park (South Africa) , Black rhinoceros -- South Africa -- Hluhluwe , Animal populations -- South Africa -- Hluhluwe , Spatial ecology -- South Africa -- Hluhluwe , Black rhinoceros -- Reproduction
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5849 , http://hdl.handle.net/10962/d1011825 , Hluhluwe-iMfolozi Park (South Africa) , Black rhinoceros -- South Africa -- Hluhluwe , Animal populations -- South Africa -- Hluhluwe , Spatial ecology -- South Africa -- Hluhluwe , Black rhinoceros -- Reproduction
- Description: Black rhinoceroses (Diceros bicornis) are endangered; there are only ~5000 individuals remaining worldwide. Consequently, black rhinos are managed as a metapopulation in southern Africa. This means that even though several sub-populations of black rhinos are geographically separated, they are managed as a single population. This is achieved by interchanging genetic material between the sub-populations. The main aim of the metapopulation management approach is to increase black rhino numbers in the sub-region. The Rhino Management Group (RMG), formed in 1989, was tasked with setting scientifically defensible demographic targets for the remaining black rhino sub-populations in southern Africa. In the same year, the RMG set fecundity rate at 25% and stated that each black rhino sub-population should achieve a minimum growth rate of 5% per year. The black rhino population in the Hluhluwe-iMfolozi Park (HiP), KwaZulu-Natal, South Africa, is of international importance as it has historically been a significant donor population for the translocation of black rhinos to establish new subpopulations elsewhere in the sub-region. However, the black rhino population at HiP is performing poorly in terms of reproductive success. My study was initiated to assess the reproductive life-histories of the black rhino population at HiP and to determine whether the population was meeting the demographic targets set by the RMG. I also wished to assess the use of space by black rhinos in HiP as a potential explanation for the observed reproductive output. Detailed life-history information for known black rhinos (n = 120) was used to investigate reproductive success between 1998 and 2012. The mean age at sexual maturity (ASM) was determined as 12 years, which is higher than the ASM found in black rhino populations that are considered to be performing poorly (ASM = ~ 7 years). The intercalving interval (ICI) was three years, nine months; this was also longer than the ICI of most black rhino populations. Further, the 2012 black rhino population at HiP had a growth rate of 6.4%, and the population comprised 60% adults, 23% sub-adults and 13% juveniles. Such demographics are usually observed in stable populations and it is possible that poor habitat quality could be resulting in the delayed ASM and longer ICI’s at HiP. In addition, 5% of the population is removed annually as part of the Black Rhino Range Expansion Program (BRREP) to establish new sub-populations. This could also be negatively influencing the reproductive performance of the HiP population. To determine the home range and habitat use of black rhinos at HiP, field data from 13 individual adult black rhinos (n = 9 females and 4 males) over a two-year period (2011-2012) were analyzed. Black rhino female home ranges were slightly smaller (15.4 ± 12.9 km²) than the home ranges of males (23.3 ±14.0 km²) and both sexes utilized similar habitats in the centre of the park. In addition, both the male and female black rhinos were found closer to rivers and drainage lines than expected. However, the assessment of black rhino space use in HiP was limited by a small sample size, making inferences of the impact of space use on reproductive success difficult. Nevertheless, my study suggests that food availability likely influences the location and sizes of black rhino home ranges at HiP. I believe that my study forms the first step in understanding the factors that influence the reproductive success and habitat use patterns of the current black rhino population at HiP. The information produced by my study should enable park management to identify future research to be conducted at HiP, which will yield more robust data for making informed black rhino management decisions at HiP and elsewhere.
- Full Text:
- Date Issued: 2014
- Authors: Nhleko, Zoliswa Nombulelo
- Date: 2014
- Subjects: Hluhluwe-iMfolozi Park (South Africa) , Black rhinoceros -- South Africa -- Hluhluwe , Animal populations -- South Africa -- Hluhluwe , Spatial ecology -- South Africa -- Hluhluwe , Black rhinoceros -- Reproduction
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5849 , http://hdl.handle.net/10962/d1011825 , Hluhluwe-iMfolozi Park (South Africa) , Black rhinoceros -- South Africa -- Hluhluwe , Animal populations -- South Africa -- Hluhluwe , Spatial ecology -- South Africa -- Hluhluwe , Black rhinoceros -- Reproduction
- Description: Black rhinoceroses (Diceros bicornis) are endangered; there are only ~5000 individuals remaining worldwide. Consequently, black rhinos are managed as a metapopulation in southern Africa. This means that even though several sub-populations of black rhinos are geographically separated, they are managed as a single population. This is achieved by interchanging genetic material between the sub-populations. The main aim of the metapopulation management approach is to increase black rhino numbers in the sub-region. The Rhino Management Group (RMG), formed in 1989, was tasked with setting scientifically defensible demographic targets for the remaining black rhino sub-populations in southern Africa. In the same year, the RMG set fecundity rate at 25% and stated that each black rhino sub-population should achieve a minimum growth rate of 5% per year. The black rhino population in the Hluhluwe-iMfolozi Park (HiP), KwaZulu-Natal, South Africa, is of international importance as it has historically been a significant donor population for the translocation of black rhinos to establish new subpopulations elsewhere in the sub-region. However, the black rhino population at HiP is performing poorly in terms of reproductive success. My study was initiated to assess the reproductive life-histories of the black rhino population at HiP and to determine whether the population was meeting the demographic targets set by the RMG. I also wished to assess the use of space by black rhinos in HiP as a potential explanation for the observed reproductive output. Detailed life-history information for known black rhinos (n = 120) was used to investigate reproductive success between 1998 and 2012. The mean age at sexual maturity (ASM) was determined as 12 years, which is higher than the ASM found in black rhino populations that are considered to be performing poorly (ASM = ~ 7 years). The intercalving interval (ICI) was three years, nine months; this was also longer than the ICI of most black rhino populations. Further, the 2012 black rhino population at HiP had a growth rate of 6.4%, and the population comprised 60% adults, 23% sub-adults and 13% juveniles. Such demographics are usually observed in stable populations and it is possible that poor habitat quality could be resulting in the delayed ASM and longer ICI’s at HiP. In addition, 5% of the population is removed annually as part of the Black Rhino Range Expansion Program (BRREP) to establish new sub-populations. This could also be negatively influencing the reproductive performance of the HiP population. To determine the home range and habitat use of black rhinos at HiP, field data from 13 individual adult black rhinos (n = 9 females and 4 males) over a two-year period (2011-2012) were analyzed. Black rhino female home ranges were slightly smaller (15.4 ± 12.9 km²) than the home ranges of males (23.3 ±14.0 km²) and both sexes utilized similar habitats in the centre of the park. In addition, both the male and female black rhinos were found closer to rivers and drainage lines than expected. However, the assessment of black rhino space use in HiP was limited by a small sample size, making inferences of the impact of space use on reproductive success difficult. Nevertheless, my study suggests that food availability likely influences the location and sizes of black rhino home ranges at HiP. I believe that my study forms the first step in understanding the factors that influence the reproductive success and habitat use patterns of the current black rhino population at HiP. The information produced by my study should enable park management to identify future research to be conducted at HiP, which will yield more robust data for making informed black rhino management decisions at HiP and elsewhere.
- Full Text:
- Date Issued: 2014
The depersonalization of the concept of ownership in contemporary society brought about by the use of title as a security device: inaugural lecture delivered at Rhodes University
- Authors: Harker, J R, 1943-
- Date: 1987
- Subjects: Property -- South Africa , Possession (Law) -- South Africa
- Language: English
- Type: Text
- Identifier: vital:634 , http://hdl.handle.net/10962/d1020703 , ISBN 0868101575
- Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1987
- Authors: Harker, J R, 1943-
- Date: 1987
- Subjects: Property -- South Africa , Possession (Law) -- South Africa
- Language: English
- Type: Text
- Identifier: vital:634 , http://hdl.handle.net/10962/d1020703 , ISBN 0868101575
- Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1987
The depiction of female characters by male writers in selected isiXhosa drama works
- Authors: Peter, Zola Welcome
- Date: 2010
- Subjects: Xhosa drama -- 20th century -- History and criticism , Women in literature , Feminism and literature , Xhosa drama -- Male authors , Gender identity in literature
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:8446 , http://hdl.handle.net/10948/1482 , Xhosa drama -- 20th century -- History and criticism , Women in literature , Feminism and literature , Xhosa drama -- Male authors , Gender identity in literature
- Description: This research expresses female character portrayal in various drama works written by males. Chapter one is a general introduction that gives the key to this study, the motivation that leads to the selection of this topic; a literary review on the portrayal of female characters in literary works written by males; the scope of study, the basic composition of the ensuing chapters and the definitions of terms that are of paramount importance for this research. Various literary theories are used in Chapter two for the analysis of the research texts. These literary theories include womanism, gender and feminism which expose the social effects caused by the negative perception of females in social life and the negative portrayal of female characters in male dramatic writings. Other literary theories include onomastics as a literary theory, which exposes the relationship between the name giver of a person and the power the name gives to its bearer, as well as psychoanalysis as a theory which proved to be unavoidable, since this study analyses the personal behaviour of the individual characters within their literary environment. Chapter three depicts the general victimization of female characters in male drama works and exposes the various effects of the attitudes of male writers towards female characters in terms of gender role. Chapter four shows a general stereotypical portrayal of female characters in male written drama texts. This chapter shows the impact of stereotyping on female characters from drama works that puts them in a vulnerable position, showing that it is risky to become a victim of ill-treatment in their communities and the literary world. Chapter five deals with the psychological literary review of female characters, showing them as being suicidal and murderers who easily take their own lives and those of other people. Chapter six is a general conclusion of the works which includes observer remarks from other literary researchers of the literature.
- Full Text:
- Date Issued: 2010
- Authors: Peter, Zola Welcome
- Date: 2010
- Subjects: Xhosa drama -- 20th century -- History and criticism , Women in literature , Feminism and literature , Xhosa drama -- Male authors , Gender identity in literature
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:8446 , http://hdl.handle.net/10948/1482 , Xhosa drama -- 20th century -- History and criticism , Women in literature , Feminism and literature , Xhosa drama -- Male authors , Gender identity in literature
- Description: This research expresses female character portrayal in various drama works written by males. Chapter one is a general introduction that gives the key to this study, the motivation that leads to the selection of this topic; a literary review on the portrayal of female characters in literary works written by males; the scope of study, the basic composition of the ensuing chapters and the definitions of terms that are of paramount importance for this research. Various literary theories are used in Chapter two for the analysis of the research texts. These literary theories include womanism, gender and feminism which expose the social effects caused by the negative perception of females in social life and the negative portrayal of female characters in male dramatic writings. Other literary theories include onomastics as a literary theory, which exposes the relationship between the name giver of a person and the power the name gives to its bearer, as well as psychoanalysis as a theory which proved to be unavoidable, since this study analyses the personal behaviour of the individual characters within their literary environment. Chapter three depicts the general victimization of female characters in male drama works and exposes the various effects of the attitudes of male writers towards female characters in terms of gender role. Chapter four shows a general stereotypical portrayal of female characters in male written drama texts. This chapter shows the impact of stereotyping on female characters from drama works that puts them in a vulnerable position, showing that it is risky to become a victim of ill-treatment in their communities and the literary world. Chapter five deals with the psychological literary review of female characters, showing them as being suicidal and murderers who easily take their own lives and those of other people. Chapter six is a general conclusion of the works which includes observer remarks from other literary researchers of the literature.
- Full Text:
- Date Issued: 2010
The deployment of an e-commerce platform and related projects in a rural area in South Africa
- Dalvit, Lorenzo, Muyingi, H Hyppolite, Terzoli, Alfredo, Thinyane, Mamello
- Authors: Dalvit, Lorenzo , Muyingi, H Hyppolite , Terzoli, Alfredo , Thinyane, Mamello
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428545 , vital:72519 , https://nru.uncst.go.ug/bitstream/handle/123456789/6552/Information%20Communica-tion%20Technologies%20%20page%20410.pdf?sequence=1andisAllowed=y#page=256
- Description: In our paper we describe the development and deployment of an ecommerce platform in Dwesa, a rural area in the former homeland of Transkei in South Africa. The system is designed to promote tourism and advertise local arts, crafts and music, and it entails a number of re-lated projects. Deployment of infrastructure, technical support, promo-tion of the initiative and teaching of computer literacy take place during monthly visits of approximately one week, and involve young research-ers from two universities (one previously disadvantaged; the other his-torically privileged). This ensures a synergy between technical exper-tise and understanding of the local context. Findings so far emphasise the importance of contextualising the intervention to suit local needs and adjust to the local context. The platform is currently being extended to include e-government, e-learning and e-health capabilities. If proven successful, this model can be exported to similar areas in South africa and in the rest of Africa. This could open up potential opportunities for the still unexplored market for ICT in rural Africa.
- Full Text:
- Date Issued: 2007
- Authors: Dalvit, Lorenzo , Muyingi, H Hyppolite , Terzoli, Alfredo , Thinyane, Mamello
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428545 , vital:72519 , https://nru.uncst.go.ug/bitstream/handle/123456789/6552/Information%20Communica-tion%20Technologies%20%20page%20410.pdf?sequence=1andisAllowed=y#page=256
- Description: In our paper we describe the development and deployment of an ecommerce platform in Dwesa, a rural area in the former homeland of Transkei in South Africa. The system is designed to promote tourism and advertise local arts, crafts and music, and it entails a number of re-lated projects. Deployment of infrastructure, technical support, promo-tion of the initiative and teaching of computer literacy take place during monthly visits of approximately one week, and involve young research-ers from two universities (one previously disadvantaged; the other his-torically privileged). This ensures a synergy between technical exper-tise and understanding of the local context. Findings so far emphasise the importance of contextualising the intervention to suit local needs and adjust to the local context. The platform is currently being extended to include e-government, e-learning and e-health capabilities. If proven successful, this model can be exported to similar areas in South africa and in the rest of Africa. This could open up potential opportunities for the still unexplored market for ICT in rural Africa.
- Full Text:
- Date Issued: 2007
The deployment of the medico-psychological gaze and disability expertise in relation to children with intellectual disability
- Mckenzie, Judith A, Macleod, Catriona I
- Authors: Mckenzie, Judith A , Macleod, Catriona I
- Date: 2012
- Language: English
- Type: Article
- Identifier: vital:6294 , http://hdl.handle.net/10962/d1014732 , http://www.tandfonline.com/doi/full/10.1080/13603116.2010.540042
- Description: In this study, we adopt the concepts of Michel Foucault on the medical gaze and Nikolas Rose on psychological expertise to differentiate between two forms of expertise evident in the education of intellectually disabled children. We draw on a discourse analytic study carried out in South Africa on intellectual disability in relation to educational practice to examine the operation of a medico-psychological gaze that calls for disability expertise in the management of disability. We conclude our discussion by noting that the dichotomy between impairment and disability that is proposed in the social model of disability does little to destabilise the power of the medico-psychological gaze since impairment is conceded to biomedical knowledge as an object of positive knowledge. This tacit acceptance of the medical authority gives sanction to disability expertise that operates in diffuse ways to regulate the educational experience of learners with intellectual disability. The implications of this conception for inclusive education are briefly explored, and further areas for research are suggested.
- Full Text:
- Date Issued: 2012
- Authors: Mckenzie, Judith A , Macleod, Catriona I
- Date: 2012
- Language: English
- Type: Article
- Identifier: vital:6294 , http://hdl.handle.net/10962/d1014732 , http://www.tandfonline.com/doi/full/10.1080/13603116.2010.540042
- Description: In this study, we adopt the concepts of Michel Foucault on the medical gaze and Nikolas Rose on psychological expertise to differentiate between two forms of expertise evident in the education of intellectually disabled children. We draw on a discourse analytic study carried out in South Africa on intellectual disability in relation to educational practice to examine the operation of a medico-psychological gaze that calls for disability expertise in the management of disability. We conclude our discussion by noting that the dichotomy between impairment and disability that is proposed in the social model of disability does little to destabilise the power of the medico-psychological gaze since impairment is conceded to biomedical knowledge as an object of positive knowledge. This tacit acceptance of the medical authority gives sanction to disability expertise that operates in diffuse ways to regulate the educational experience of learners with intellectual disability. The implications of this conception for inclusive education are briefly explored, and further areas for research are suggested.
- Full Text:
- Date Issued: 2012
The depositional history and evaluation of two late quaternary, diamondiferous pocket beaches, south-western Namibia
- Authors: Milad, Micael George
- Date: 2004-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/420934 , vital:71795
- Description: The two Late Quaternary, diamondiferous pocket beach deposits studied here are situated along a 10 km stretch of the storm-dominated, Atlantic coastline of the Sperrgebiet, south-western Namibia. The pocket beaches are approximately 130 km north of the Orange River mouth, which is widely accepted as a long-lived point source for diamonds sourced from the interior of southern Africa. A total of fourteen pocket beach deposits were recently evaluated in this area, but only two of these, namely Site 2 (to the south) and Site 3 (to the north), are considered here. The main diamondbearing horizons are beach gravels, which occur within, and form part of, the pocket beach sequences. The beach gravels are mostly blanketed by sand overburden, meaning that exposures available for study were limited, and much reliance was placed on borehole logging and observations of evaluation sample tailings. The main aims are to unravel the depositional history of the pocket beach sequences, identify the controls on diamond mineralisation in the beach gravels, and critically examine two different methods of estimating average diamond size for the deposits. In pursuit of these aims, sedimentological characteristics of the unconsolidated pocket beach deposits were recorded using small diameter drill holes, hydraulic grab bulk samples, trench exposures and surface outcrops. The surface geology, geomorphology and modern wave patterns were mapped using high-resolution, Airborne Laser Survey imagery coupled with extensive field checking. Three-dimensional geological modeling software was used to gain insight into the subsurface morphology of the deposits. Fossil shell samples were used to aid interpretation of ancient depositional environments and to date parts of the pocket beach sequences. Variations in diamond concentration and the size of diamonds were recorded using bulk samples, some of which were taken from a trench, but most of which were excavated using a hydraulic grab tool called the GB50. Finally, by using diamond size data from Site 3, sample data from diamondiferous beach gravels to the south of the study area and sample campaign simulations, two alternative methods of evaluating average diamond size in marine gravel deposits were appraised.The pocket beach sequences occur within north-south trending valleys of a major deflation basin and are separated from one another by rocky headlands. The ridge-and-valley topography of the deflation basin has resulted from differential erosion of Late Proterozoic basement rock units, alternating layers of which differ greatly in their resistance to the long-lived, local denudationalprocesses. On the basis of the stratigraphic information collected from the unconsolidated pocket beach valley fills, interpreted within the context of global, Late Pleistocene sea level records, the following depositional history is deduced : a) Deposition of sheetflood gravels by ephemeral streams, activated during a regressive phase. b) Transgression, culminating in the deposition of a gravel beach, representing a sea level highstand of +4 metres above mean sea level (mamsl) at between 120 000 and 130 000 BP. c)A regressive phase, resulting in deflation of former valley fills to the bedrock valley floor and accompanied by re-activation of ephemeral stream activity to form sheetflood deposits; this represents a protracted period of subaerial exposure of the +4 m gravel beach deposit. d) Deposition of a great volume of sediment in the valleys during the latter stages of the transgression from the Last Glacial Maximum (LGM). The sequence generated during this phase, which started at ca. 9 000 BP, contains : i) pan/coastal sabkha sediments, ii) shallow, sheltered bay sediments, iii) back-barrier lagoonal sediments, iv) a gravel beach deposit representing a sea level stillstand at -5 mamsl, laid down between 7 600 and 5 600 BP, v) another gravel beach deposit representing the well-known Middle Holocene sea level highstand at +2 to +3 mamsl, laid down at ca. 5 000 BP, and which terminated the transgression from the LGM. e) A minor regression to the current sea level, accompanied by progradation of the shoreline to its current position. This progradational marine unit consists almost entirely of sand and grit, reflecting the lack of gravel supply to this part of the coastline in the most recent past. f) Deposition of modern coastal dunes, which cap the pocket beach sequence and are the youngest sediments in the study area. Using trench and hydraulic grab evaluation sample results, in combination with analysis of wave patterns and field observations, the following local controls on the density distribution (ie. concentration) and size distribution of diamonds in the gravel beach deposits (+4, -5 and +2 to +3 mamsl stands) are recognised: a) Gravel beach depositional processes, which are responsible for clast sorting on the beach, have influenced the density and size distribution of diamonds. The infill zone, or beach toe, favours maximum diamond concentration while diamond size decreases from the imbricate zone (intertidal) to the infill zone (subtidal). b) Wave energy is identified as the dominant local control on diamond size distribution, but has also influenced diamond concentration to a limited degree. Larger diamonds are intimately associated with coarser beach gravels, both of which are a reflection of increased wave energy. Higher concentrations of diamonds are sometimes associated with zones of coarser gravel and therefore greater wave energy. c) The time of deposition of the host gravel beach is seen to be the dominant controlling factor with respect to diamond concentration. This is seen as evidence of significant temporal variation in the availability of diamonds in the littoral evironment. A significant reduction (20%) in average diamond size from Site 2 to Site 3, over a distance of only 6 km, is evident. The following were identified as reasons for this reduction in diamond size : a) Longshore sorting processes, of which the long-lived northerly littoral drift is a key part, are known to have played a role in the diminution of diamond size northwards from the Orange River mouth point source. However, it is believed that this can only partly account for the observed 20% reduction in diamond size. b) Input of sediment and smaller diamonds at Site 3, reworked out of an older, Eocene-aged marine succession in the hinterland, is recognised as a possible additional reason for the large reduction in diamond size from Site 2 to Site 3. It is also speculated that the large size of the pocket beach at Site 3, relative to Site 2, may have resulted in lower average wave energy at Site 3, with consequent reduced average diamond size. Diamond size in the beach gravels of Site 3, as well as in beach gravels elsewhere in the Sperrgebiet, is seen to be lognormally-distributed within geologically homogeneous zones. In theory, lognormal mean estimators represent the best method of estimating average diamond size in such cases, whereas the arithmetic mean estimator has the tendency to overestimate when large outlier values occur. Lognormal mean estimators have the added benefit of providing for the calculation of confidence limits, which are becoming increasingly more important as financial lending institutions insist on better quantification of the risk involved in resource estimates. Sample campaign simulations demonstrate, for the kinds of diamond size-frequency distributions typical of beach gravel deposits at Site 3, that there is no significant improvement in the accuracy of average diamond size estimates when lognormal mean estimators are used instead of the arithmetic mean estimator. This is because the variance (a ) of the diamond populations is low, and large outlier values are extremely unlikely to occur. However, simulation of a diamond population with high variance, drawn from a sample of beach gravels near the Orange River mouth, shows that lognormal estimators produce significantly more accurate results when a is large. Since individual diamond weights were not recorded during evaluation sampling of Site 3, numerical solution of lognormal estimators is not possible, and these would need to be solved using a less accurate graphical method. It is therefore recommended that individual diamond weights are recorded in future sampling campaigns, allowing for the use of lognormal mean estimators, and the calculation of confidence limits for average diamond size estimates. , Thesis (MSc) -- Science, Geology, 2004
- Full Text:
- Date Issued: 2004-03
- Authors: Milad, Micael George
- Date: 2004-03
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/420934 , vital:71795
- Description: The two Late Quaternary, diamondiferous pocket beach deposits studied here are situated along a 10 km stretch of the storm-dominated, Atlantic coastline of the Sperrgebiet, south-western Namibia. The pocket beaches are approximately 130 km north of the Orange River mouth, which is widely accepted as a long-lived point source for diamonds sourced from the interior of southern Africa. A total of fourteen pocket beach deposits were recently evaluated in this area, but only two of these, namely Site 2 (to the south) and Site 3 (to the north), are considered here. The main diamondbearing horizons are beach gravels, which occur within, and form part of, the pocket beach sequences. The beach gravels are mostly blanketed by sand overburden, meaning that exposures available for study were limited, and much reliance was placed on borehole logging and observations of evaluation sample tailings. The main aims are to unravel the depositional history of the pocket beach sequences, identify the controls on diamond mineralisation in the beach gravels, and critically examine two different methods of estimating average diamond size for the deposits. In pursuit of these aims, sedimentological characteristics of the unconsolidated pocket beach deposits were recorded using small diameter drill holes, hydraulic grab bulk samples, trench exposures and surface outcrops. The surface geology, geomorphology and modern wave patterns were mapped using high-resolution, Airborne Laser Survey imagery coupled with extensive field checking. Three-dimensional geological modeling software was used to gain insight into the subsurface morphology of the deposits. Fossil shell samples were used to aid interpretation of ancient depositional environments and to date parts of the pocket beach sequences. Variations in diamond concentration and the size of diamonds were recorded using bulk samples, some of which were taken from a trench, but most of which were excavated using a hydraulic grab tool called the GB50. Finally, by using diamond size data from Site 3, sample data from diamondiferous beach gravels to the south of the study area and sample campaign simulations, two alternative methods of evaluating average diamond size in marine gravel deposits were appraised.The pocket beach sequences occur within north-south trending valleys of a major deflation basin and are separated from one another by rocky headlands. The ridge-and-valley topography of the deflation basin has resulted from differential erosion of Late Proterozoic basement rock units, alternating layers of which differ greatly in their resistance to the long-lived, local denudationalprocesses. On the basis of the stratigraphic information collected from the unconsolidated pocket beach valley fills, interpreted within the context of global, Late Pleistocene sea level records, the following depositional history is deduced : a) Deposition of sheetflood gravels by ephemeral streams, activated during a regressive phase. b) Transgression, culminating in the deposition of a gravel beach, representing a sea level highstand of +4 metres above mean sea level (mamsl) at between 120 000 and 130 000 BP. c)A regressive phase, resulting in deflation of former valley fills to the bedrock valley floor and accompanied by re-activation of ephemeral stream activity to form sheetflood deposits; this represents a protracted period of subaerial exposure of the +4 m gravel beach deposit. d) Deposition of a great volume of sediment in the valleys during the latter stages of the transgression from the Last Glacial Maximum (LGM). The sequence generated during this phase, which started at ca. 9 000 BP, contains : i) pan/coastal sabkha sediments, ii) shallow, sheltered bay sediments, iii) back-barrier lagoonal sediments, iv) a gravel beach deposit representing a sea level stillstand at -5 mamsl, laid down between 7 600 and 5 600 BP, v) another gravel beach deposit representing the well-known Middle Holocene sea level highstand at +2 to +3 mamsl, laid down at ca. 5 000 BP, and which terminated the transgression from the LGM. e) A minor regression to the current sea level, accompanied by progradation of the shoreline to its current position. This progradational marine unit consists almost entirely of sand and grit, reflecting the lack of gravel supply to this part of the coastline in the most recent past. f) Deposition of modern coastal dunes, which cap the pocket beach sequence and are the youngest sediments in the study area. Using trench and hydraulic grab evaluation sample results, in combination with analysis of wave patterns and field observations, the following local controls on the density distribution (ie. concentration) and size distribution of diamonds in the gravel beach deposits (+4, -5 and +2 to +3 mamsl stands) are recognised: a) Gravel beach depositional processes, which are responsible for clast sorting on the beach, have influenced the density and size distribution of diamonds. The infill zone, or beach toe, favours maximum diamond concentration while diamond size decreases from the imbricate zone (intertidal) to the infill zone (subtidal). b) Wave energy is identified as the dominant local control on diamond size distribution, but has also influenced diamond concentration to a limited degree. Larger diamonds are intimately associated with coarser beach gravels, both of which are a reflection of increased wave energy. Higher concentrations of diamonds are sometimes associated with zones of coarser gravel and therefore greater wave energy. c) The time of deposition of the host gravel beach is seen to be the dominant controlling factor with respect to diamond concentration. This is seen as evidence of significant temporal variation in the availability of diamonds in the littoral evironment. A significant reduction (20%) in average diamond size from Site 2 to Site 3, over a distance of only 6 km, is evident. The following were identified as reasons for this reduction in diamond size : a) Longshore sorting processes, of which the long-lived northerly littoral drift is a key part, are known to have played a role in the diminution of diamond size northwards from the Orange River mouth point source. However, it is believed that this can only partly account for the observed 20% reduction in diamond size. b) Input of sediment and smaller diamonds at Site 3, reworked out of an older, Eocene-aged marine succession in the hinterland, is recognised as a possible additional reason for the large reduction in diamond size from Site 2 to Site 3. It is also speculated that the large size of the pocket beach at Site 3, relative to Site 2, may have resulted in lower average wave energy at Site 3, with consequent reduced average diamond size. Diamond size in the beach gravels of Site 3, as well as in beach gravels elsewhere in the Sperrgebiet, is seen to be lognormally-distributed within geologically homogeneous zones. In theory, lognormal mean estimators represent the best method of estimating average diamond size in such cases, whereas the arithmetic mean estimator has the tendency to overestimate when large outlier values occur. Lognormal mean estimators have the added benefit of providing for the calculation of confidence limits, which are becoming increasingly more important as financial lending institutions insist on better quantification of the risk involved in resource estimates. Sample campaign simulations demonstrate, for the kinds of diamond size-frequency distributions typical of beach gravel deposits at Site 3, that there is no significant improvement in the accuracy of average diamond size estimates when lognormal mean estimators are used instead of the arithmetic mean estimator. This is because the variance (a ) of the diamond populations is low, and large outlier values are extremely unlikely to occur. However, simulation of a diamond population with high variance, drawn from a sample of beach gravels near the Orange River mouth, shows that lognormal estimators produce significantly more accurate results when a is large. Since individual diamond weights were not recorded during evaluation sampling of Site 3, numerical solution of lognormal estimators is not possible, and these would need to be solved using a less accurate graphical method. It is therefore recommended that individual diamond weights are recorded in future sampling campaigns, allowing for the use of lognormal mean estimators, and the calculation of confidence limits for average diamond size estimates. , Thesis (MSc) -- Science, Geology, 2004
- Full Text:
- Date Issued: 2004-03
The design and assessment of an integrated municipal waste beneficiation facility : towards improved sewage sludge management in developing countries
- Authors: Keirungi, Juliana
- Date: 2007
- Subjects: Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4755 , http://hdl.handle.net/10962/d1007138 , Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Description: This research aimed to firstly confirm the hypothesis that the current management of sewage sludge generated during the treatment of wastewater in the Eastern Cape Province of South Africa is poor and, as such, this material poses a threat to local environmental and human health. Secondly, through a rational design approach, the current research also aimed to design and assess the suitability of a novel integrated process incorporating appropriate technologies for improved sewage sludge management. The lack of an appropriate tool for the assessment of the integrated process necessitated the development of an appropriate technology assessment (TA) methodology based on environmental, technical, social and economic criteria. A combination of informal participatory methods such as semi-structured interviews and formal research methods including questionnaires, risk assessment exercises and laboratory analyses were used. Based on the above it was estimated that 116 tons dry sludge were generated in the province per day and that the concentration of heavy metals present in the sludge was generally within the limits for reuse on agricultural land. Furthermore the sludge from all sample sewage treatment works (STWs) was found to be free of any detectable pathogens. Despite the above, a preliminary risk assessment and chemical analysis revealed that existing sludge management practices at sample STWs posed a threat to the environment, particularly to water resources and exacerbated the problems associated with the discharge of poorly treated municipal wastewater. The root causes of the poor sludge management were considered to be a lack of non-regulatory incentives and financial resources. Highly integrated ecologically engineered systems were thought to offer a solution to the dual problem of poor sludge management and municipal effluent treatment, while providing necessary economic incentives. To facilitate the design of a system appropriate to local conditions, it was necessary to first develop a rational design methodology, which incorporated a detailed TA step. The result of the design process was an Integrated Waste Beneficiation Facility (IWBF) that incorporated a number of process units comprised of appropriate technologies including composting, vermicomposting, algal ponding technology and aquaculture. A detailed TA indicated that the benefits of the proposed IWBF would, at the majority of sample sites, outweigh the potential negative impacts and it was thus recommended that investigations should continue on pilot-scale facilities. Furthermore, although the proposed TA based on four sustainability criteria categories was thought to provide a more accurate assessment of the true sustainability of a technology, the acquisition of information was problematic highlighting the need to re-think current TA methodologies and to address associated constraints allowing the tool to be used and fully comprehensive.
- Full Text:
- Date Issued: 2007
- Authors: Keirungi, Juliana
- Date: 2007
- Subjects: Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4755 , http://hdl.handle.net/10962/d1007138 , Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Description: This research aimed to firstly confirm the hypothesis that the current management of sewage sludge generated during the treatment of wastewater in the Eastern Cape Province of South Africa is poor and, as such, this material poses a threat to local environmental and human health. Secondly, through a rational design approach, the current research also aimed to design and assess the suitability of a novel integrated process incorporating appropriate technologies for improved sewage sludge management. The lack of an appropriate tool for the assessment of the integrated process necessitated the development of an appropriate technology assessment (TA) methodology based on environmental, technical, social and economic criteria. A combination of informal participatory methods such as semi-structured interviews and formal research methods including questionnaires, risk assessment exercises and laboratory analyses were used. Based on the above it was estimated that 116 tons dry sludge were generated in the province per day and that the concentration of heavy metals present in the sludge was generally within the limits for reuse on agricultural land. Furthermore the sludge from all sample sewage treatment works (STWs) was found to be free of any detectable pathogens. Despite the above, a preliminary risk assessment and chemical analysis revealed that existing sludge management practices at sample STWs posed a threat to the environment, particularly to water resources and exacerbated the problems associated with the discharge of poorly treated municipal wastewater. The root causes of the poor sludge management were considered to be a lack of non-regulatory incentives and financial resources. Highly integrated ecologically engineered systems were thought to offer a solution to the dual problem of poor sludge management and municipal effluent treatment, while providing necessary economic incentives. To facilitate the design of a system appropriate to local conditions, it was necessary to first develop a rational design methodology, which incorporated a detailed TA step. The result of the design process was an Integrated Waste Beneficiation Facility (IWBF) that incorporated a number of process units comprised of appropriate technologies including composting, vermicomposting, algal ponding technology and aquaculture. A detailed TA indicated that the benefits of the proposed IWBF would, at the majority of sample sites, outweigh the potential negative impacts and it was thus recommended that investigations should continue on pilot-scale facilities. Furthermore, although the proposed TA based on four sustainability criteria categories was thought to provide a more accurate assessment of the true sustainability of a technology, the acquisition of information was problematic highlighting the need to re-think current TA methodologies and to address associated constraints allowing the tool to be used and fully comprehensive.
- Full Text:
- Date Issued: 2007
The design and construction of a recording spectrometer for the measurement of fluorescence excitation spectra in the vacuum ultra-violet region
- Authors: Davidson, A T
- Date: 1963
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:21177 , http://hdl.handle.net/10962/6761
- Description: Summary: A recording spectrometer for the measurement of fluorescence excitation spectra in the visible and ultra-violet regions of the spectrum is described. A direct method of modulating the hydrogen light source of the spectrograph is presented, whereby the discharge is driven by an A.C. power oscillator. The use of tuned amplifiers in the detecting unit is investigated as a means of eliminating the D.C. component of the dark current. Aspects of the modulation method are discussed. Fluorescence and energy transfer in aromatic hydrocarbon is discussed with particular regard to anthracene. Some absorption, fluorescence, excitation and reflection spectra of anthracene obtained by previous workers are presented9 together with Tables listing the wavelengths of principal maxima for the above spectra published in the literature. Features of the excitation spectrum of anthracene are discussed and are related to its absorption and fluorescence spectra. The role of surface effects, defects and impurities are discussed in relation to the fluorescence of anthracene. The method of A.C. detection was unable to resolve the excitation spectrum of anthracene due to the high noise level associated with the method. However, peaks in the ultra-violet region of the hydrogen molecular spectrum were recorded at a modulation frequency of 400 Kc/sec. The noise level is explained and ways of improving the signal to noise ratio of the A.C. detection system are suggested. It is concluded that D.C. detection is a simpler and more direct way of measuring excitation spectra. No modulated signals were detected when the hydrogen discharge was excited at 6·5 Mc/sec. Signals were recorded at modulation frequencies of 400 Kc/sec . The degree of modulation at 400 Kc/sec. increased with decrease in the pressure of the hydrogen discharge.
- Full Text:
- Date Issued: 1963
- Authors: Davidson, A T
- Date: 1963
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:21177 , http://hdl.handle.net/10962/6761
- Description: Summary: A recording spectrometer for the measurement of fluorescence excitation spectra in the visible and ultra-violet regions of the spectrum is described. A direct method of modulating the hydrogen light source of the spectrograph is presented, whereby the discharge is driven by an A.C. power oscillator. The use of tuned amplifiers in the detecting unit is investigated as a means of eliminating the D.C. component of the dark current. Aspects of the modulation method are discussed. Fluorescence and energy transfer in aromatic hydrocarbon is discussed with particular regard to anthracene. Some absorption, fluorescence, excitation and reflection spectra of anthracene obtained by previous workers are presented9 together with Tables listing the wavelengths of principal maxima for the above spectra published in the literature. Features of the excitation spectrum of anthracene are discussed and are related to its absorption and fluorescence spectra. The role of surface effects, defects and impurities are discussed in relation to the fluorescence of anthracene. The method of A.C. detection was unable to resolve the excitation spectrum of anthracene due to the high noise level associated with the method. However, peaks in the ultra-violet region of the hydrogen molecular spectrum were recorded at a modulation frequency of 400 Kc/sec. The noise level is explained and ways of improving the signal to noise ratio of the A.C. detection system are suggested. It is concluded that D.C. detection is a simpler and more direct way of measuring excitation spectra. No modulated signals were detected when the hydrogen discharge was excited at 6·5 Mc/sec. Signals were recorded at modulation frequencies of 400 Kc/sec . The degree of modulation at 400 Kc/sec. increased with decrease in the pressure of the hydrogen discharge.
- Full Text:
- Date Issued: 1963
The design and evaluation of a short-term group psychotherapy model for survivors of a first myocardial infarction
- Authors: Frewen, Sharon H
- Date: 2005
- Subjects: Health -- Psychological aspects , Medicine and psychology , Coronary heart disease -- Psychological aspects , Type A behavior , Stress (Psychology)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3247 , http://hdl.handle.net/10962/d1015041
- Description: There is extensive evidence that the rehabilitation of individuals with coronary heart disease needs to include psychological components to complement the exercise and dietary recommendations that are normally provided. However, psychological aspects have not been integrated into medical care in South Africa to any significant degree. Psychological interventions overseas have included the modification of the Type A behaviour pattern, stress management, cognitive restructuring, relaxation techniques, improved communication skills, the identification and expression of emotions, and emotional support. The aim of the present study was to design a short-term group intervention which incorporated these aspects and which included an exploration of the mind-body experience post infarct. In addition, the intervention aimed to increase participants' awareness of the compensatory dynamics of the Type A behaviour pattern. The intervention was tailored to South African conditions and was evaluated by means of a multiple case study design. The intervention was delivered to a group of nine coronary heart disease patients which included six survivors of myocardial infarction, the remaining participants having undergone a by-pass operation. Data included weekly feedback sheets evaluating each session, repeated measures on the Profile of Mood States, the Jenkins Activity Survey, a Spouse Rating Scale and extensive qualitative data on each participant including tape recordings of each session and data collected from a series of interviews before, during and after the programme. The feedback sheets and recordings of the sessions were used as a basis for recommendations for revising the content and structure of the programme for future use. Case narratives were written for three of the participants and provided an in-depth look at how and why individual changes did or did not occur in response to the intervention. In addition, the case narratives revealed the role played by the compensatory dynamics of the Type A behaviour pattern in complicating rehabilitation for survivors of myocardial infarction. Two participants were offered a series of individual sessions at 18-month follow-up and the material from these sessions was also used to aid in the interpretation of the data. The content of the 18-month follow-up sessions provided evidence for the importance of conducting a developmental analysis of the origins of low self-esteem and insecurity that maintain and drive the Type A behaviour pattern. In these sessions, this analysis provided the basis for a brief focused psychodynamic psychotherapy that facilitated marked changes that had not been achieved in the 12-week structured group intervention. It is recommended that future research investigate the use of brief psychodynamic psychotherapy on an individual basis as a complement to a group intervention focusing on psycho-education, building social support and management of problematic emotions in everyday situations.
- Full Text:
- Date Issued: 2005
- Authors: Frewen, Sharon H
- Date: 2005
- Subjects: Health -- Psychological aspects , Medicine and psychology , Coronary heart disease -- Psychological aspects , Type A behavior , Stress (Psychology)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3247 , http://hdl.handle.net/10962/d1015041
- Description: There is extensive evidence that the rehabilitation of individuals with coronary heart disease needs to include psychological components to complement the exercise and dietary recommendations that are normally provided. However, psychological aspects have not been integrated into medical care in South Africa to any significant degree. Psychological interventions overseas have included the modification of the Type A behaviour pattern, stress management, cognitive restructuring, relaxation techniques, improved communication skills, the identification and expression of emotions, and emotional support. The aim of the present study was to design a short-term group intervention which incorporated these aspects and which included an exploration of the mind-body experience post infarct. In addition, the intervention aimed to increase participants' awareness of the compensatory dynamics of the Type A behaviour pattern. The intervention was tailored to South African conditions and was evaluated by means of a multiple case study design. The intervention was delivered to a group of nine coronary heart disease patients which included six survivors of myocardial infarction, the remaining participants having undergone a by-pass operation. Data included weekly feedback sheets evaluating each session, repeated measures on the Profile of Mood States, the Jenkins Activity Survey, a Spouse Rating Scale and extensive qualitative data on each participant including tape recordings of each session and data collected from a series of interviews before, during and after the programme. The feedback sheets and recordings of the sessions were used as a basis for recommendations for revising the content and structure of the programme for future use. Case narratives were written for three of the participants and provided an in-depth look at how and why individual changes did or did not occur in response to the intervention. In addition, the case narratives revealed the role played by the compensatory dynamics of the Type A behaviour pattern in complicating rehabilitation for survivors of myocardial infarction. Two participants were offered a series of individual sessions at 18-month follow-up and the material from these sessions was also used to aid in the interpretation of the data. The content of the 18-month follow-up sessions provided evidence for the importance of conducting a developmental analysis of the origins of low self-esteem and insecurity that maintain and drive the Type A behaviour pattern. In these sessions, this analysis provided the basis for a brief focused psychodynamic psychotherapy that facilitated marked changes that had not been achieved in the 12-week structured group intervention. It is recommended that future research investigate the use of brief psychodynamic psychotherapy on an individual basis as a complement to a group intervention focusing on psycho-education, building social support and management of problematic emotions in everyday situations.
- Full Text:
- Date Issued: 2005
The design and evaluation of targeted patient-centred health information to improve knowledge and behavioural outcomes in tuberculosis patients with limited literacy
- Authors: Patel, Sonal
- Date: 2015
- Subjects: Tuberculosis Patients , Health literacy , Patient education , Communication in medicine , Picture-writing
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/194071 , vital:45420 , DOI 10.21504/10962/194071
- Description: South Africa carries a significant TB burden as evidenced in the 2013 statistics which report 450 000 new active TB cases and 890 000 TB-related mortalities. For successful treatment outcomes, 90% adherence is necessary, but many patients prematurely discontinue treatment due to poor knowledge and understanding of their complex TB medicines. Patient education is pivotal in improving knowledge, health literacy and behavioural outcomes such as health information seeking, self-efficacy and adherence. In the under-resourced South African healthcare system, time and capacity to adequately counsel patients are limited. The value of written medicine information (WMI) to supplement the verbal information provided by healthcare professionals (HCPs) has been widely investigated but minimal South African research is available. Current WMI distributed in South Africa is mainly generated by pharmaceutical manufacturers and is complex, incomprehensible and undesirable to patients. TB-related WMI focuses mainly on the disease, with little information relating to TB medicines and their use. The overall aim of this project was to improve patient knowledge about their TB medicines through the use of a simple illustrated patient information leaflet (PIL). Objectives to achieve this aim included: investigation of the medicine information seeking behaviour (MISB) of long term patients attending public health sector facilities; the development and validation of a medicine literacy test (MLT) to identify patients with limited health literacy requiring additional support and counselling; the development and evaluation of a patient-centred illustrated PIL for first-line TB treatment; the assessment of self-efficacy and adherence using modified versions of the HIV Treatment Adherence Self-Efficacy Scale (HIV-ASES) and Morisky 8-item Medicine Adherence Scale (MMAS-8), respectively, and the investigation of the impact of the PIL on patient knowledge and these health-related behaviours. Six focus group discussions (FGDs) conducted in 34 isiXhosa-speaking patients with limited formal education taking long-term treatment explored themes related to information needs, information-seeking practices and awareness of and ability to utilize information sources. Codes were analysed and potential themes and subthemes were identified and refined. The findings of this study reflected a passive, disempowered patient due to both patient-related and systemic healthcare factors. Poor awareness of information sources, lack of health-related knowledge, stigma and lack of awareness of the importance of appropriate medicine-related knowledge contributed to a lack of information-seeking practice. Patients neither asked questions nor were encouraged to do so. All expressed an unmet need for information and a desire for receiving relevant, appropriate, written medicine-related information. Feedback from this phase of the study was used to inform the development of the targeted patientcentred PIL. A double-sided A4 PIL containing information about TB medicines was designed giving careful consideration to content, format and layout features. Twenty five pictograms were designed through a rigorous, iterative design process and were included in the PIL that was evaluated in a randomised control trial (RCT) conducted amongst 120 TB patients attending a high burden TB clinic in South Africa. Interviews were conducted in either isiXhosa or Afrikaans via a trained interpreter. Patients were randomly allocated to either a control (standard care) or an experimental group (standard care plus brief counselling using the PIL). Two interviews were conducted using a prepared questionnaire; one at baseline followed by a 4-week follow-up. Baseline data included demographics, medicine literacy test, health information sources, knowledge of TB medicines, self-reported adherence and self-efficacy. Data collected at the 4-week follow-up interview included TB knowledge, self-reported adherence, self-efficacy, opinion of TB medicine information and interpretation of pictograms. Data were analysed using t-test, correlations, chi-square and ANOVA tests at a 0.05 level of significance. The PIL was successful in improving patient knowledge of the disease, TB medicine-taking, side effects, drug-resistant TB and HIV and TB co-infection. At baseline, there was no significant difference in the overall mean percentage knowledge score between the control and experimental groups (p=0.074). At follow-up, the percentage knowledge score for the experimental group increased significantly from 59.0% to 84.6% (p<0.001) and showed a significantly higher score than the control group (p<0.001), displaying evidence of the impact of the PIL as a counselling tool on patient knowledge. The PIL generated a highly positive response in the experimental group who indicated that they had referred to the leaflet over the last month and that it had played an important role in improving their TB medicine-related knowledge. This was reflected in the experimental group knowledge score of greater than 80% for almost three quarters of the patients whereas only 14% in the control group achieved this score. Patients appreciated the inclusion of pictograms and strongly felt that they helped them to recall and understand the textual PIL content. The study found that patients want side effect information and, interestingly, did not perceive the presentation of side effects in pictorial form to constitute a risk factor for nonadherence. Use of the illustrated PIL (experimental group) resulted in a significant improvement in patient self-efficacy (p=0.002), but showed no effect on self-reported adherence (p=0.563). Neither self-efficacy nor adherence was influenced by gender, age or education. An education effect on knowledge was only observed in the control group at baseline. The newly developed MLT was shown to be a valid and reliable tool and a moderate, positive and significant correlation was noted between the MLT score and baseline TB medicine-related knowledge in both the control and experimental groups. As there is a paucity of studies investigating the influence of take-home written leaflets on TB medicine knowledge and on patient behaviour, this study represents a significant knowledge contribution. It is the first study to report the development and evaluation of a patient-centred PIL to address the dearth of available TB medicine information. The use of targeted user-friendly, illustrated information leaflets can be a valuable counselling aid to improve patient knowledge and self-efficacy, particularly among patients with limited literacy. However, careful consideration of the design and content, with input from the endusers at all stages of the process, will optimise its effectiveness. The proposed framework for the development and implementation of patient-centred health and medicines information in a developing country context presented in this thesis could be used as a theoretical basis for informing the development of effective information materials targeting other disease states. Local patients taking TB medicines identified nurses, WMI and media as their current sources of information but they expressed a strong desire to know more about their treatment. Targeted public health interventions that focus on medicine-taking information and behaviours and encourage patients to adopt a more active, questioning role in health consultations could improve health literacy and empower patients in their medicine-taking practices. , Thesis (PhD) -- Faculty of Pharmacy, Pharmacy, 2015
- Full Text:
- Date Issued: 2015
- Authors: Patel, Sonal
- Date: 2015
- Subjects: Tuberculosis Patients , Health literacy , Patient education , Communication in medicine , Picture-writing
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/194071 , vital:45420 , DOI 10.21504/10962/194071
- Description: South Africa carries a significant TB burden as evidenced in the 2013 statistics which report 450 000 new active TB cases and 890 000 TB-related mortalities. For successful treatment outcomes, 90% adherence is necessary, but many patients prematurely discontinue treatment due to poor knowledge and understanding of their complex TB medicines. Patient education is pivotal in improving knowledge, health literacy and behavioural outcomes such as health information seeking, self-efficacy and adherence. In the under-resourced South African healthcare system, time and capacity to adequately counsel patients are limited. The value of written medicine information (WMI) to supplement the verbal information provided by healthcare professionals (HCPs) has been widely investigated but minimal South African research is available. Current WMI distributed in South Africa is mainly generated by pharmaceutical manufacturers and is complex, incomprehensible and undesirable to patients. TB-related WMI focuses mainly on the disease, with little information relating to TB medicines and their use. The overall aim of this project was to improve patient knowledge about their TB medicines through the use of a simple illustrated patient information leaflet (PIL). Objectives to achieve this aim included: investigation of the medicine information seeking behaviour (MISB) of long term patients attending public health sector facilities; the development and validation of a medicine literacy test (MLT) to identify patients with limited health literacy requiring additional support and counselling; the development and evaluation of a patient-centred illustrated PIL for first-line TB treatment; the assessment of self-efficacy and adherence using modified versions of the HIV Treatment Adherence Self-Efficacy Scale (HIV-ASES) and Morisky 8-item Medicine Adherence Scale (MMAS-8), respectively, and the investigation of the impact of the PIL on patient knowledge and these health-related behaviours. Six focus group discussions (FGDs) conducted in 34 isiXhosa-speaking patients with limited formal education taking long-term treatment explored themes related to information needs, information-seeking practices and awareness of and ability to utilize information sources. Codes were analysed and potential themes and subthemes were identified and refined. The findings of this study reflected a passive, disempowered patient due to both patient-related and systemic healthcare factors. Poor awareness of information sources, lack of health-related knowledge, stigma and lack of awareness of the importance of appropriate medicine-related knowledge contributed to a lack of information-seeking practice. Patients neither asked questions nor were encouraged to do so. All expressed an unmet need for information and a desire for receiving relevant, appropriate, written medicine-related information. Feedback from this phase of the study was used to inform the development of the targeted patientcentred PIL. A double-sided A4 PIL containing information about TB medicines was designed giving careful consideration to content, format and layout features. Twenty five pictograms were designed through a rigorous, iterative design process and were included in the PIL that was evaluated in a randomised control trial (RCT) conducted amongst 120 TB patients attending a high burden TB clinic in South Africa. Interviews were conducted in either isiXhosa or Afrikaans via a trained interpreter. Patients were randomly allocated to either a control (standard care) or an experimental group (standard care plus brief counselling using the PIL). Two interviews were conducted using a prepared questionnaire; one at baseline followed by a 4-week follow-up. Baseline data included demographics, medicine literacy test, health information sources, knowledge of TB medicines, self-reported adherence and self-efficacy. Data collected at the 4-week follow-up interview included TB knowledge, self-reported adherence, self-efficacy, opinion of TB medicine information and interpretation of pictograms. Data were analysed using t-test, correlations, chi-square and ANOVA tests at a 0.05 level of significance. The PIL was successful in improving patient knowledge of the disease, TB medicine-taking, side effects, drug-resistant TB and HIV and TB co-infection. At baseline, there was no significant difference in the overall mean percentage knowledge score between the control and experimental groups (p=0.074). At follow-up, the percentage knowledge score for the experimental group increased significantly from 59.0% to 84.6% (p<0.001) and showed a significantly higher score than the control group (p<0.001), displaying evidence of the impact of the PIL as a counselling tool on patient knowledge. The PIL generated a highly positive response in the experimental group who indicated that they had referred to the leaflet over the last month and that it had played an important role in improving their TB medicine-related knowledge. This was reflected in the experimental group knowledge score of greater than 80% for almost three quarters of the patients whereas only 14% in the control group achieved this score. Patients appreciated the inclusion of pictograms and strongly felt that they helped them to recall and understand the textual PIL content. The study found that patients want side effect information and, interestingly, did not perceive the presentation of side effects in pictorial form to constitute a risk factor for nonadherence. Use of the illustrated PIL (experimental group) resulted in a significant improvement in patient self-efficacy (p=0.002), but showed no effect on self-reported adherence (p=0.563). Neither self-efficacy nor adherence was influenced by gender, age or education. An education effect on knowledge was only observed in the control group at baseline. The newly developed MLT was shown to be a valid and reliable tool and a moderate, positive and significant correlation was noted between the MLT score and baseline TB medicine-related knowledge in both the control and experimental groups. As there is a paucity of studies investigating the influence of take-home written leaflets on TB medicine knowledge and on patient behaviour, this study represents a significant knowledge contribution. It is the first study to report the development and evaluation of a patient-centred PIL to address the dearth of available TB medicine information. The use of targeted user-friendly, illustrated information leaflets can be a valuable counselling aid to improve patient knowledge and self-efficacy, particularly among patients with limited literacy. However, careful consideration of the design and content, with input from the endusers at all stages of the process, will optimise its effectiveness. The proposed framework for the development and implementation of patient-centred health and medicines information in a developing country context presented in this thesis could be used as a theoretical basis for informing the development of effective information materials targeting other disease states. Local patients taking TB medicines identified nurses, WMI and media as their current sources of information but they expressed a strong desire to know more about their treatment. Targeted public health interventions that focus on medicine-taking information and behaviours and encourage patients to adopt a more active, questioning role in health consultations could improve health literacy and empower patients in their medicine-taking practices. , Thesis (PhD) -- Faculty of Pharmacy, Pharmacy, 2015
- Full Text:
- Date Issued: 2015
The design and implementation of a fourth generation programming language
- Authors: Iverson, Carn Martin
- Date: 1989 , 2013-03-04
- Subjects: Programming languages (Electronic computers) , Fourth generation computers
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4584 , http://hdl.handle.net/10962/d1004652 , Programming languages (Electronic computers) , Fourth generation computers
- Description: IV is a very high level language designed for use in a real time production control environment. While most fourth generation languages are intended for use by end users, IV is more suitable for skilled professional programmers. One of the major design objectives of IV is a dramatic improvement in programmer efficiency during application program development. Non-procedural constructs provided by the language and the use of a number of interactive development tools provide an environment for achieving this goal. This report presents a language proposal for IV, and addresses related design and implementation issues.
- Full Text:
- Date Issued: 1989
- Authors: Iverson, Carn Martin
- Date: 1989 , 2013-03-04
- Subjects: Programming languages (Electronic computers) , Fourth generation computers
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4584 , http://hdl.handle.net/10962/d1004652 , Programming languages (Electronic computers) , Fourth generation computers
- Description: IV is a very high level language designed for use in a real time production control environment. While most fourth generation languages are intended for use by end users, IV is more suitable for skilled professional programmers. One of the major design objectives of IV is a dramatic improvement in programmer efficiency during application program development. Non-procedural constructs provided by the language and the use of a number of interactive development tools provide an environment for achieving this goal. This report presents a language proposal for IV, and addresses related design and implementation issues.
- Full Text:
- Date Issued: 1989
The design and synthesis of multidentate N-heterocyclic carbenes as metathesis catalyst ligands
- Authors: Truscott, Byron John
- Date: 2011
- Subjects: Carbenes (Methylene compounds) , Heterocyclic compounds , Ligands , Ligands -- Design , Metathesis (Chemistry) , Catalysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4304 , http://hdl.handle.net/10962/d1004962 , Carbenes (Methylene compounds) , Heterocyclic compounds , Ligands , Ligands -- Design , Metathesis (Chemistry) , Catalysis
- Description: This study has focused on the design and preparation of bi– and tridentate N–Heterocyclic Carbene (NHC) ligands in order to investigate the effect of a multidentate approach to the formation, stability and catalytic activity of coordination complexes. Chapters 1 – 3 provide background information of relevant catalysis, carbene and coordination chemistry, followed by previous work performed within our research group. In Chapter 4 attention is given to the synthetic aspects of the research conducted, comprising two distinct approaches to the preparation of unsymmetrical saturated and unsaturated NHCs. Firstly, an investigation of the saturated NHC ligands yielded three novel, unsymmetrical pro–ligands, viz., two halopropyl imidazolinium salts and a bidentate hydroxypropyl imidazolinium salt. Secondly, eight imidazolium salts have been generated, including a hydroxypropyl analogue and novel decyl and tridentate malonyl derivatives. These compounds were prepared using microwave–assisted methodology for the alkylation of N– mesitylimidazole – an approach that drastically reduced reaction times (from 8 hours – 7 days to ca. 0.5 – 2 hours) and facilitated isolation of the imidazolium salts. Many of the compounds prepared in this study are novel and were fully characterized using HRMS and 1– and 2–D NMR analysis. Coordination studies using a selection of the prepared pro–ligands afforded an alkoxy–NHC silver derivative and four novel Ru–complexes, viz., Grubbs II–type Ru–complexes containing:– chloropropyl imidazolinylidene; propenyl imidazolylidene; and bidentate alkoxypropyl imidazolylidene ligands. Furthermore, a well–defined benzyl mesitylimidazolylidene Ru–complex has been isolated, which exhibited good stability in air. DFT–level geometry–optimization studies, using the Accelrys DMol3 package have given valuable insights into the likely geometries of the prepared and putative catalysts.
- Full Text:
- Date Issued: 2011
- Authors: Truscott, Byron John
- Date: 2011
- Subjects: Carbenes (Methylene compounds) , Heterocyclic compounds , Ligands , Ligands -- Design , Metathesis (Chemistry) , Catalysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4304 , http://hdl.handle.net/10962/d1004962 , Carbenes (Methylene compounds) , Heterocyclic compounds , Ligands , Ligands -- Design , Metathesis (Chemistry) , Catalysis
- Description: This study has focused on the design and preparation of bi– and tridentate N–Heterocyclic Carbene (NHC) ligands in order to investigate the effect of a multidentate approach to the formation, stability and catalytic activity of coordination complexes. Chapters 1 – 3 provide background information of relevant catalysis, carbene and coordination chemistry, followed by previous work performed within our research group. In Chapter 4 attention is given to the synthetic aspects of the research conducted, comprising two distinct approaches to the preparation of unsymmetrical saturated and unsaturated NHCs. Firstly, an investigation of the saturated NHC ligands yielded three novel, unsymmetrical pro–ligands, viz., two halopropyl imidazolinium salts and a bidentate hydroxypropyl imidazolinium salt. Secondly, eight imidazolium salts have been generated, including a hydroxypropyl analogue and novel decyl and tridentate malonyl derivatives. These compounds were prepared using microwave–assisted methodology for the alkylation of N– mesitylimidazole – an approach that drastically reduced reaction times (from 8 hours – 7 days to ca. 0.5 – 2 hours) and facilitated isolation of the imidazolium salts. Many of the compounds prepared in this study are novel and were fully characterized using HRMS and 1– and 2–D NMR analysis. Coordination studies using a selection of the prepared pro–ligands afforded an alkoxy–NHC silver derivative and four novel Ru–complexes, viz., Grubbs II–type Ru–complexes containing:– chloropropyl imidazolinylidene; propenyl imidazolylidene; and bidentate alkoxypropyl imidazolylidene ligands. Furthermore, a well–defined benzyl mesitylimidazolylidene Ru–complex has been isolated, which exhibited good stability in air. DFT–level geometry–optimization studies, using the Accelrys DMol3 package have given valuable insights into the likely geometries of the prepared and putative catalysts.
- Full Text:
- Date Issued: 2011
The design and synthesis of novel fluorescent coumarin-based derivatives as chemosensory for the application of toxic metal ion detection
- Authors: Schoeman,Stiaan
- Date: 2023-04
- Subjects: Fluorescent polymers -- South Africa , Polymerization , Chemosensory
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/61270 , vital:69851
- Description: The rise of humankind has caused pollution, increasing damage to the environment. The actions of humans over hundreds of years have led to an increase in the release of heavy metal cations in concentrations that are toxic to plants, animals and humans. These toxic metals can find their way into humans’ diets through water sources or bioaccumulation in plants and animals such as fish. Heavy metals such as lead and mercury are known to cause serious health issues when consumed, affecting the functioning of the circulatory and nervous systems and causing developmental disorders. Other metal cations, such as iron and copper, can be found in the human body. However, detrimental health issues can occur when normal concentrations are disturbed (either too high or too low). Iron, for example, can be toxic if in excess in the human body, causing damage to the liver and heart and can cause neuroinflammation and Alzheimer’s disease. Many methods have been employed to detect and measure the concentrations of toxic metal cations. However, these methods are performed in a laboratory and need skilled operators using expensive equipment. This results in long and tedious sample collection, long feedback time and costly analysis. Chemosensors have been researched and proposed as a cost-effective, on-site, real-time alternative for use as metal detectors. Chemosensory can selectively detect specific metal cations and can be sensitive up to the nanomolar range. Various chemosensors have been synthesised and screened for their colourimetric and fluorometric abilities. Colourimetric chemosensors can be used to visually detect cationic and anionic analytes, whereas fluorometric chemosensors are used to detect anions using their emission properties which handheld devices can measure. , Thesis (PhD) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2023
- Full Text:
- Date Issued: 2023-04
- Authors: Schoeman,Stiaan
- Date: 2023-04
- Subjects: Fluorescent polymers -- South Africa , Polymerization , Chemosensory
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/61270 , vital:69851
- Description: The rise of humankind has caused pollution, increasing damage to the environment. The actions of humans over hundreds of years have led to an increase in the release of heavy metal cations in concentrations that are toxic to plants, animals and humans. These toxic metals can find their way into humans’ diets through water sources or bioaccumulation in plants and animals such as fish. Heavy metals such as lead and mercury are known to cause serious health issues when consumed, affecting the functioning of the circulatory and nervous systems and causing developmental disorders. Other metal cations, such as iron and copper, can be found in the human body. However, detrimental health issues can occur when normal concentrations are disturbed (either too high or too low). Iron, for example, can be toxic if in excess in the human body, causing damage to the liver and heart and can cause neuroinflammation and Alzheimer’s disease. Many methods have been employed to detect and measure the concentrations of toxic metal cations. However, these methods are performed in a laboratory and need skilled operators using expensive equipment. This results in long and tedious sample collection, long feedback time and costly analysis. Chemosensors have been researched and proposed as a cost-effective, on-site, real-time alternative for use as metal detectors. Chemosensory can selectively detect specific metal cations and can be sensitive up to the nanomolar range. Various chemosensors have been synthesised and screened for their colourimetric and fluorometric abilities. Colourimetric chemosensors can be used to visually detect cationic and anionic analytes, whereas fluorometric chemosensors are used to detect anions using their emission properties which handheld devices can measure. , Thesis (PhD) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2023
- Full Text:
- Date Issued: 2023-04
The design and synthesis of novel HIV-1 protease inhibitors
- Authors: Tukulula, Matshawandile
- Date: 2009
- Subjects: Protease Inhibitors HIV infections -- Treatment AIDS (Disease) -- Treatment HIV (Viruses) Indolizine -- Derivatives Heterocyclic compounds -- Derivatives Nuclear magnetic resonance Quinoline
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4305 , http://hdl.handle.net/10962/d1004963
- Description: This study has focused on the synthesis of truncated analogues of the hydroxyethylene dipeptide isosteres, such as Ritonavir®, currently in clinical use as HIV-1 protease inhibitors. The reactions of pyridine-2- and quinoline-2-carbaldehydes with methyl acrylate, in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) or 3- hydroxyquinuclidine (3-HQ) as nucleophilic catalysts, have afforded a series of Baylis- Hillman adducts, acetylation and cyclisation of which have provided access to a series of indolizine-2-carboxylate esters. The carboxylic acids, obtained by base-catalyzed hydrolysis of these esters, have been coupled with various protected (and unprotected) amino compounds using the peptide coupling agent, 1,1’-carbonyldiimidazole (CDI), to afford a series of indolizine-2-carboxamides as indolizine-based truncated Ritonavir® analogues in quantitative yield. Aza-Michael reactions of pyridine-3-carbaldehydederived Baylis-Hillman adducts with various amino compounds have provided access to a range of pyridine-based products as mixtures of diastereomeric aza-Michael products. The assignment of the relative stereochemistry of the aza-Michael products has been established using 1-D and 2-NOESY experiments and computer modelling techniques. Computer modelling studies have also been conducted on selected aza-Michael products using ACCELRYS Cerius2 software, followed by interactive docking into the HIV-1 protease receptor site, using AUTODOCK 4.0. The docking studies have revealed hydrogen-bonding interactions between the enzyme and the synthetic ligands. Saturation Transfer Difference (STD) NMR experiments have also indicated binding of some of the aza-Michael products to the HIV-1 protease subtype C enzyme, thus indicating their binding and possible inhibitory potential.
- Full Text:
- Date Issued: 2009
- Authors: Tukulula, Matshawandile
- Date: 2009
- Subjects: Protease Inhibitors HIV infections -- Treatment AIDS (Disease) -- Treatment HIV (Viruses) Indolizine -- Derivatives Heterocyclic compounds -- Derivatives Nuclear magnetic resonance Quinoline
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4305 , http://hdl.handle.net/10962/d1004963
- Description: This study has focused on the synthesis of truncated analogues of the hydroxyethylene dipeptide isosteres, such as Ritonavir®, currently in clinical use as HIV-1 protease inhibitors. The reactions of pyridine-2- and quinoline-2-carbaldehydes with methyl acrylate, in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) or 3- hydroxyquinuclidine (3-HQ) as nucleophilic catalysts, have afforded a series of Baylis- Hillman adducts, acetylation and cyclisation of which have provided access to a series of indolizine-2-carboxylate esters. The carboxylic acids, obtained by base-catalyzed hydrolysis of these esters, have been coupled with various protected (and unprotected) amino compounds using the peptide coupling agent, 1,1’-carbonyldiimidazole (CDI), to afford a series of indolizine-2-carboxamides as indolizine-based truncated Ritonavir® analogues in quantitative yield. Aza-Michael reactions of pyridine-3-carbaldehydederived Baylis-Hillman adducts with various amino compounds have provided access to a range of pyridine-based products as mixtures of diastereomeric aza-Michael products. The assignment of the relative stereochemistry of the aza-Michael products has been established using 1-D and 2-NOESY experiments and computer modelling techniques. Computer modelling studies have also been conducted on selected aza-Michael products using ACCELRYS Cerius2 software, followed by interactive docking into the HIV-1 protease receptor site, using AUTODOCK 4.0. The docking studies have revealed hydrogen-bonding interactions between the enzyme and the synthetic ligands. Saturation Transfer Difference (STD) NMR experiments have also indicated binding of some of the aza-Michael products to the HIV-1 protease subtype C enzyme, thus indicating their binding and possible inhibitory potential.
- Full Text:
- Date Issued: 2009
The design and testing of a national estuarine monitoring prgramme for South Africa
- Authors: Cilliers, Gerhard Jordaan
- Date: 2017
- Subjects: Estuaries -- South Africa Berg Estuary (South Africa)
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/15490 , vital:28258
- Description: Adaptive water resource management requires sound scientific based decisions, emanating from robust scientific data. The Department of Environmental Affairs are mandated for collaborative management of the South African coast, including estuaries, through the Integrated Coastal Management Act (Act no 24 of 2008) (ICMA). The Department Water and Sanitation is mandated through the National Water Act (Act no 36 of 1998) (NWA) to design, test and implement monitoring programmes to provide water resource data. Extensive freshwater monitoring programmes exist in South Africa but there is no standard long-term monitoring programme for estuaries. This study designed and tested a National Estuarine Monitoring Programme (NESMP) that is anchored in the NWA and the ICMA. The design was based on a review of international estuary monitoring programmes, consultation with relevant role players and five decades experience in the design, testing and implementation of water resource monitoring programmes by DWS. The main objective of this thesis is 1) to design a national estuarine monitoring programme 2) test the design of the programme for practical implementation by reflecting on collected data from case studies, and 3) design a Decision Support System to translate complex monitoring data into management information. The main objective of the NESMP is 1) to collect long-term data to determine trends in the condition of estuaries in South Africa and 2) to provide management orientated information for effective estuary management. The National Estuary Monitoring programme consists of three tiers. Tier 1 focuses on basic data including system variables and nutrient data. Tier 2 collects data required for the determination of the Ecological Water Requirements (EWR) of estuaries in accordance with a standardised method used by DWS. A tailor made monitoring programme addressing specific issues including pollution incidents and localised development pressure, making use of a combination of Tier 1 and Tier 2 components, forms Tier 3 of the NESMP. This study tested the Tier 1 components of the programme on 28 estuaries across the South African coast since 2012. However, due to space constraints, the data reflected on in this thesis, is only for case studies on the Berg and Breede estuaries between 2012 and 2016. The results indicate that the establishment and operation of the NESMP on South African estuaries making use of monthly surveys, and the deployment of permanent water quality loggers, in line with the proposed protocol, are possible. This does however require collaboration with other role players in order to share responsibility and associated resources. A tiered management structure ensures national, regional and local level implementation takes place seamlessly. A decision support system (DSS) was also designed as part of this thesis to assist with data interpretation and the creation of management orientated information. This DSS includes a measurement of the percentage exceedance of the Threshold of Potential Concern (TPC), which acts as an early warning system for water resource deterioration. This study showed that effective collaboration will ensure the sustainability of the NESMP. Implementation of the more complex and resource intensive Tier 2 and Tier 3 sampling will however need to be investigated to establish the overall success of the NESMP.
- Full Text:
- Date Issued: 2017
- Authors: Cilliers, Gerhard Jordaan
- Date: 2017
- Subjects: Estuaries -- South Africa Berg Estuary (South Africa)
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/15490 , vital:28258
- Description: Adaptive water resource management requires sound scientific based decisions, emanating from robust scientific data. The Department of Environmental Affairs are mandated for collaborative management of the South African coast, including estuaries, through the Integrated Coastal Management Act (Act no 24 of 2008) (ICMA). The Department Water and Sanitation is mandated through the National Water Act (Act no 36 of 1998) (NWA) to design, test and implement monitoring programmes to provide water resource data. Extensive freshwater monitoring programmes exist in South Africa but there is no standard long-term monitoring programme for estuaries. This study designed and tested a National Estuarine Monitoring Programme (NESMP) that is anchored in the NWA and the ICMA. The design was based on a review of international estuary monitoring programmes, consultation with relevant role players and five decades experience in the design, testing and implementation of water resource monitoring programmes by DWS. The main objective of this thesis is 1) to design a national estuarine monitoring programme 2) test the design of the programme for practical implementation by reflecting on collected data from case studies, and 3) design a Decision Support System to translate complex monitoring data into management information. The main objective of the NESMP is 1) to collect long-term data to determine trends in the condition of estuaries in South Africa and 2) to provide management orientated information for effective estuary management. The National Estuary Monitoring programme consists of three tiers. Tier 1 focuses on basic data including system variables and nutrient data. Tier 2 collects data required for the determination of the Ecological Water Requirements (EWR) of estuaries in accordance with a standardised method used by DWS. A tailor made monitoring programme addressing specific issues including pollution incidents and localised development pressure, making use of a combination of Tier 1 and Tier 2 components, forms Tier 3 of the NESMP. This study tested the Tier 1 components of the programme on 28 estuaries across the South African coast since 2012. However, due to space constraints, the data reflected on in this thesis, is only for case studies on the Berg and Breede estuaries between 2012 and 2016. The results indicate that the establishment and operation of the NESMP on South African estuaries making use of monthly surveys, and the deployment of permanent water quality loggers, in line with the proposed protocol, are possible. This does however require collaboration with other role players in order to share responsibility and associated resources. A tiered management structure ensures national, regional and local level implementation takes place seamlessly. A decision support system (DSS) was also designed as part of this thesis to assist with data interpretation and the creation of management orientated information. This DSS includes a measurement of the percentage exceedance of the Threshold of Potential Concern (TPC), which acts as an early warning system for water resource deterioration. This study showed that effective collaboration will ensure the sustainability of the NESMP. Implementation of the more complex and resource intensive Tier 2 and Tier 3 sampling will however need to be investigated to establish the overall success of the NESMP.
- Full Text:
- Date Issued: 2017
The design and use of a data base for the teaching of history at primary school level
- Authors: Paul, James R M
- Date: 1994
- Subjects: Education -- Data processing History -- Study and teaching (Elementary) -- Data processing Computer-assisted instruction
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1490 , http://hdl.handle.net/10962/d1003371
- Description: The changes brought about by society's move from an industrial to an information society has brought with it changes in the way that society operates - from the way we do business to the way we entertain ourselves and, increasingly, in the way we educate our children. That the society of tomorrow requires new skills to survive and operate had been, and continues to be, debated in a growing number of books and in the popular media. More and more educationists are calling for schools to 'restructure' so as to be able to provide the skills that this new society requires, especially those related to the management of information. The nature of these skills are discussed, together with the potential provided by information technology, particularly computers, to provide them. The current use of computers in schools is addressed, together with the apparent inability of schools to generate effective change from within using in-service training. The researcher suggests that this makes it imperative that teacher training institutions provide the next generation of teacher-trainees with a thorough understanding of the requirements of an information society and the tools that it uses. The research undertaken attempted to provide final year primary education teacher-trainees with one example of the way in which the electronic database can be used to change the teaching of history. By researching in the field and entering data into a data base, the teacher-trainees were able to look at information in new ways. By selecting and sorting data by different fields, they were able to act as ' true' historians - each interacting with the data in his or her own way to extract knowledge that is arguably unique for each participant. The data base was then used with a class of standard four pupils, with the researcher acting as participant observer. The reactions and responses of the pupils to the data was noted and these are discussed in the results . A non-participant observer, also a primary school history -teacher, provided input with respect to the validity of the learning experience and to act as a control. The research is described, together with the observations of the researcher, teacher-trainees and pupils involved. The observations of the non-participant observer are also discussed. Shortfalls and difficulties encountered are pointed out, and areas for further research suggested.
- Full Text:
- Date Issued: 1994
- Authors: Paul, James R M
- Date: 1994
- Subjects: Education -- Data processing History -- Study and teaching (Elementary) -- Data processing Computer-assisted instruction
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1490 , http://hdl.handle.net/10962/d1003371
- Description: The changes brought about by society's move from an industrial to an information society has brought with it changes in the way that society operates - from the way we do business to the way we entertain ourselves and, increasingly, in the way we educate our children. That the society of tomorrow requires new skills to survive and operate had been, and continues to be, debated in a growing number of books and in the popular media. More and more educationists are calling for schools to 'restructure' so as to be able to provide the skills that this new society requires, especially those related to the management of information. The nature of these skills are discussed, together with the potential provided by information technology, particularly computers, to provide them. The current use of computers in schools is addressed, together with the apparent inability of schools to generate effective change from within using in-service training. The researcher suggests that this makes it imperative that teacher training institutions provide the next generation of teacher-trainees with a thorough understanding of the requirements of an information society and the tools that it uses. The research undertaken attempted to provide final year primary education teacher-trainees with one example of the way in which the electronic database can be used to change the teaching of history. By researching in the field and entering data into a data base, the teacher-trainees were able to look at information in new ways. By selecting and sorting data by different fields, they were able to act as ' true' historians - each interacting with the data in his or her own way to extract knowledge that is arguably unique for each participant. The data base was then used with a class of standard four pupils, with the researcher acting as participant observer. The reactions and responses of the pupils to the data was noted and these are discussed in the results . A non-participant observer, also a primary school history -teacher, provided input with respect to the validity of the learning experience and to act as a control. The research is described, together with the observations of the researcher, teacher-trainees and pupils involved. The observations of the non-participant observer are also discussed. Shortfalls and difficulties encountered are pointed out, and areas for further research suggested.
- Full Text:
- Date Issued: 1994
The design of a 21st century administrative headquarters for the city of Gqeberha
- Authors: Borchers, Spencer Phillip
- Date: 2022-04
- Subjects: Municipal buildings -- South Africa -- Gqeberha -- Designs and plans , Architecture, Modern -- 20th century -- Designs and plans
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/57443 , vital:57870
- Description: This treatise developed through an interest in 21st century office buildings and the impact they have on the well-being of occupants. The office of the 20th century disregarded well-being and was focused on efficiently accommodating the functions of the workplace in an effort to increase productivity. Today, many of these buildings inadequately provide for the basic biological, psychological, and social needs required for the work force of the 21 st century. The nature of the office has shifted to a more socially interactive and flexible environment which attempts to obtain productivity targets through nurturing the well-being of occupants. Research has determined that biological health can be supported through the optimization of building performance; psychological health can be supported through considering environmental psychology; and social health can be supported through instilling a robust corporate culture. This treatise takes a qualitative research approach to thoroughly interpret the informants and constraints of the site in order to design additions and alterations to the existing administrative headquarters for the Nelson Mandela Bay Municipality. The updated facility will consolidate the administrative functions of local government into one 21st century administrative headquarters, located on the sites of three current NMBM offices in Govan Mbeki Avenue. , Thesis (MArch) -- Faculty of Engineering, the Built Environment and Technology, School of Architecture, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Borchers, Spencer Phillip
- Date: 2022-04
- Subjects: Municipal buildings -- South Africa -- Gqeberha -- Designs and plans , Architecture, Modern -- 20th century -- Designs and plans
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/57443 , vital:57870
- Description: This treatise developed through an interest in 21st century office buildings and the impact they have on the well-being of occupants. The office of the 20th century disregarded well-being and was focused on efficiently accommodating the functions of the workplace in an effort to increase productivity. Today, many of these buildings inadequately provide for the basic biological, psychological, and social needs required for the work force of the 21 st century. The nature of the office has shifted to a more socially interactive and flexible environment which attempts to obtain productivity targets through nurturing the well-being of occupants. Research has determined that biological health can be supported through the optimization of building performance; psychological health can be supported through considering environmental psychology; and social health can be supported through instilling a robust corporate culture. This treatise takes a qualitative research approach to thoroughly interpret the informants and constraints of the site in order to design additions and alterations to the existing administrative headquarters for the Nelson Mandela Bay Municipality. The updated facility will consolidate the administrative functions of local government into one 21st century administrative headquarters, located on the sites of three current NMBM offices in Govan Mbeki Avenue. , Thesis (MArch) -- Faculty of Engineering, the Built Environment and Technology, School of Architecture, 2022
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- Date Issued: 2022-04
The design of a 21st century headquarters for the Transnet National Ports Authority in the port of East London
- Authors: Ramjee, Neche'
- Date: 2018
- Subjects: Harbors -- South Africa -- East London -- Design and construction Marine terminals -- Design and construction National Ports Authority of South Africa
- Language: English
- Type: Thesis , Masters , MArch
- Identifier: http://hdl.handle.net/10948/23801 , vital:30621
- Description: Ports form part of an international global network that facilitates trade and economic growth. This thesis is born out of interest in communicating economic prosperity and corporate identity in a modern South African society through the design of a headquarters for the state owned company (parastatal), Transnet National Ports Authority. This paper unpacks and the reviews the strategies, methods and tools when interpreting corporate identity into corporate architecture as well as the issues and challenges when establishing a corporate identity for a parastatal company in connection with the potential role and impact that ports have on urban development in the 21st Century. Qualitative research has been conducted to investigate and understand what corporate identity is in order to establish the key symbolic components which signify a brand, within its national context, to its users, clients and the public. Furthermore theory relating to place is used in order to establish the relationship between man and nature has also been investigated in order to appropriate principles of wellness and sustainability within a corporate environment which are site specific. This provides a platform for an architectural intervention which responds to the ecological and urban issues of the site, as harbours have a dominant land use in a city they have significant implications for the physical and environmental features thereof. The findings will lead to an appropriate brief which will arrive at a design response which is an authentic architectural expression of the company’s corporate identity. An office building typology will be investigated and implemented onto the site to successfully communicate the brand and contextual identity. Urban strategies which seek to marry the rigid industrial processes with its active public interface will be investigated in order to contribute to promote trade on the East London waterfront.
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- Date Issued: 2018
- Authors: Ramjee, Neche'
- Date: 2018
- Subjects: Harbors -- South Africa -- East London -- Design and construction Marine terminals -- Design and construction National Ports Authority of South Africa
- Language: English
- Type: Thesis , Masters , MArch
- Identifier: http://hdl.handle.net/10948/23801 , vital:30621
- Description: Ports form part of an international global network that facilitates trade and economic growth. This thesis is born out of interest in communicating economic prosperity and corporate identity in a modern South African society through the design of a headquarters for the state owned company (parastatal), Transnet National Ports Authority. This paper unpacks and the reviews the strategies, methods and tools when interpreting corporate identity into corporate architecture as well as the issues and challenges when establishing a corporate identity for a parastatal company in connection with the potential role and impact that ports have on urban development in the 21st Century. Qualitative research has been conducted to investigate and understand what corporate identity is in order to establish the key symbolic components which signify a brand, within its national context, to its users, clients and the public. Furthermore theory relating to place is used in order to establish the relationship between man and nature has also been investigated in order to appropriate principles of wellness and sustainability within a corporate environment which are site specific. This provides a platform for an architectural intervention which responds to the ecological and urban issues of the site, as harbours have a dominant land use in a city they have significant implications for the physical and environmental features thereof. The findings will lead to an appropriate brief which will arrive at a design response which is an authentic architectural expression of the company’s corporate identity. An office building typology will be investigated and implemented onto the site to successfully communicate the brand and contextual identity. Urban strategies which seek to marry the rigid industrial processes with its active public interface will be investigated in order to contribute to promote trade on the East London waterfront.
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- Date Issued: 2018
The design of a 3D printing facility in Central, Port Elizabeth
- Authors: Huiskens, Riaan
- Date: 2018
- Subjects: Architecture and technology -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MArch
- Identifier: http://hdl.handle.net/10948/23739 , vital:30615
- Description: High-tech architecture is moving towards a paradigm shift with the development and incorporation of digital fabrication technology. This interest is extended into the discussion of recycling existing infrastructure. In this treatise, a topic which ties into both the heritage and ecological discourse. It recognises the significance of historical urban elements and the finite quality of heritage resources within the city. A historical building used as a host for the design of a 3D printing facility invites a dialogue between the architecture of the old and the expression of the new. The Premier Mill Building is identified as an historical urban artefact and the proposed programme complements the historical background of the building, which was a granary. A building from another time, now caught in a post-industrial age. The primary architectural exploration focuses on the possibilities offered by 3D printing in the making and expression of architecture. Therefore research is focused on the types and processes of 3D printing and there products. Secondly, the treatise employs an urban artefact as a vehicle of expression for a new programme, which requires an understanding of the topic of marrying present and past architecture. In the treatise the city, is understood through the work of Aldo Rossi’s conceptual perspective of the city. Further, the topic of digital tectonic is explored in order to establish an expression of digital fabrication. Heritage and conservation principles are investigated to complete a theoretical understanding of the project. This treatise document is a record of the design process from start to finish. The document unpacks the treatise through its various stages of growth: project background; research; design strategies and final design.
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- Date Issued: 2018
- Authors: Huiskens, Riaan
- Date: 2018
- Subjects: Architecture and technology -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MArch
- Identifier: http://hdl.handle.net/10948/23739 , vital:30615
- Description: High-tech architecture is moving towards a paradigm shift with the development and incorporation of digital fabrication technology. This interest is extended into the discussion of recycling existing infrastructure. In this treatise, a topic which ties into both the heritage and ecological discourse. It recognises the significance of historical urban elements and the finite quality of heritage resources within the city. A historical building used as a host for the design of a 3D printing facility invites a dialogue between the architecture of the old and the expression of the new. The Premier Mill Building is identified as an historical urban artefact and the proposed programme complements the historical background of the building, which was a granary. A building from another time, now caught in a post-industrial age. The primary architectural exploration focuses on the possibilities offered by 3D printing in the making and expression of architecture. Therefore research is focused on the types and processes of 3D printing and there products. Secondly, the treatise employs an urban artefact as a vehicle of expression for a new programme, which requires an understanding of the topic of marrying present and past architecture. In the treatise the city, is understood through the work of Aldo Rossi’s conceptual perspective of the city. Further, the topic of digital tectonic is explored in order to establish an expression of digital fabrication. Heritage and conservation principles are investigated to complete a theoretical understanding of the project. This treatise document is a record of the design process from start to finish. The document unpacks the treatise through its various stages of growth: project background; research; design strategies and final design.
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- Date Issued: 2018