Photophysicochemical and photodynamic antimicrobial chemotherapeutic studies of novel phthalocyanines conjugated to silver nanoparticles
- Authors: Rapulenyane, Nomasonto
- Date: 2013 , 2013-06-10
- Subjects: Phthalocyanines , Photochemistry , Photochemotherapy , Cancer -- Photochemotherapy , Anti-infective agents , Escherichia coli , Nanoparticles , Silver , Zinc
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4291 , http://hdl.handle.net/10962/d1003912 , Phthalocyanines , Photochemistry , Photochemotherapy , Cancer -- Photochemotherapy , Anti-infective agents , Escherichia coli , Nanoparticles , Silver , Zinc
- Description: This work reports on the synthesis, characterization and the physicochemical properties of novel unsymmetrically substituted zinc phthalocyanines: namely tris{11,19, 27-(1,2- diethylaminoethylthiol)-2-(captopril) phthalocyanine Zn ((ZnMCapPc (1.5)), hexakis{8,11,16,19,42,27-(octylthio)-1-(4-phenoxycarboxy) phthalocyanine} Zn (ZnMPCPc(1.7)) and Tris {11, 19, 27-(1,2-diethylaminoethylthiol)-1,2(caffeic acid) phthalocyanine} Zn ((ZnMCafPc (1.3)). Symmetrically substituted counterparts (tetrakis(diethylamino)zinc phthalocyaninato (3.8), octakis(octylthio)zinc phthalocyaninato (3.9) and tetrakis (carboxyphenoxy)zinc phthalocyaninato (3.10) complexes) were also synthesized for comparison of the photophysicochemical properties and to investigate the effect of the substituents on the low symmetry Pcs. The complexes were successfully characterized by IR, NMR, mass spectral and elemental analyses. All the complexes showed the ability to produce singlet oxygen, while the highest triplet quantum yields were obtained for 1.7, 1.5 and 3.9 (0.80, 0.65 and 0.62 respectively and the lowest were obtained for 1.3 and 3.10 (0.57 and 0.47 respectively). High triplet lifetimes (109-286 μs) were also obtained for all complexes, with 1.7 being the highest (286 μs) which also corresponds to its triplet and singlet quantum yields (0.80 and 0.77 respectively). The photosensitizing properties of low symmetry derivatives, ZnMCapPc and ZnMCafPc were investigated by conjugating glutathione (GSH) capped silver nanoparticles (AgNP). The formation of the amide bond was confirmed by IR and UV-Vis spectroscopies. The photophysicochemical behaviour of the novel phthalocyanine-GSH-AgNP conjugates and the simple mixture of the Ag NPs with low the symmetry phthalocyanines were investigated. It was observed that upon conjugation of the phthalocyanines to the GSH-AgNPs, a blue shift in the Q band was induced. The triplet lifetimes and quantum yields improved upon conjugation as compared to the phthalocyanines (Pc) alone. Complex 1.5 triplet lifetimes increased from 109 to 148 and triplet quantum yield from 0.65 to 0.86 upon conjugation. Fluorescence lifetimes and quantum yields decreased for the conjugates compared to the phthalocyanines alone, due to the quenching caused by the Ag NPs. The antimicrobial activity of the zinc phthalocyanines (complexes 1.3 and 1.5) and their conjugates against Escherichia coli was investigated. Only 1.3 and 1.5 complexes were investigated because of the availability of the sample. In general phthalocyanines showed increase in antibacterial activity with the increase in phthalocyanines concentration in the presence and absence of light. The Pc complexes and their Ag NP conjugates showed an increase in antibacterial activity, due to the synergistic effect afforded by Ag NP and Pcs. Improved antibacterial properties were obtained upon irradiation. 1.5-AgNPs had the highest antibacterial activity compared to 1.3-AgNPs conjugate; these results are in agreement with the photophysical behaviour. This work demonstrates improved photophysicochemical properties of low symm
- Full Text:
- Authors: Rapulenyane, Nomasonto
- Date: 2013 , 2013-06-10
- Subjects: Phthalocyanines , Photochemistry , Photochemotherapy , Cancer -- Photochemotherapy , Anti-infective agents , Escherichia coli , Nanoparticles , Silver , Zinc
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4291 , http://hdl.handle.net/10962/d1003912 , Phthalocyanines , Photochemistry , Photochemotherapy , Cancer -- Photochemotherapy , Anti-infective agents , Escherichia coli , Nanoparticles , Silver , Zinc
- Description: This work reports on the synthesis, characterization and the physicochemical properties of novel unsymmetrically substituted zinc phthalocyanines: namely tris{11,19, 27-(1,2- diethylaminoethylthiol)-2-(captopril) phthalocyanine Zn ((ZnMCapPc (1.5)), hexakis{8,11,16,19,42,27-(octylthio)-1-(4-phenoxycarboxy) phthalocyanine} Zn (ZnMPCPc(1.7)) and Tris {11, 19, 27-(1,2-diethylaminoethylthiol)-1,2(caffeic acid) phthalocyanine} Zn ((ZnMCafPc (1.3)). Symmetrically substituted counterparts (tetrakis(diethylamino)zinc phthalocyaninato (3.8), octakis(octylthio)zinc phthalocyaninato (3.9) and tetrakis (carboxyphenoxy)zinc phthalocyaninato (3.10) complexes) were also synthesized for comparison of the photophysicochemical properties and to investigate the effect of the substituents on the low symmetry Pcs. The complexes were successfully characterized by IR, NMR, mass spectral and elemental analyses. All the complexes showed the ability to produce singlet oxygen, while the highest triplet quantum yields were obtained for 1.7, 1.5 and 3.9 (0.80, 0.65 and 0.62 respectively and the lowest were obtained for 1.3 and 3.10 (0.57 and 0.47 respectively). High triplet lifetimes (109-286 μs) were also obtained for all complexes, with 1.7 being the highest (286 μs) which also corresponds to its triplet and singlet quantum yields (0.80 and 0.77 respectively). The photosensitizing properties of low symmetry derivatives, ZnMCapPc and ZnMCafPc were investigated by conjugating glutathione (GSH) capped silver nanoparticles (AgNP). The formation of the amide bond was confirmed by IR and UV-Vis spectroscopies. The photophysicochemical behaviour of the novel phthalocyanine-GSH-AgNP conjugates and the simple mixture of the Ag NPs with low the symmetry phthalocyanines were investigated. It was observed that upon conjugation of the phthalocyanines to the GSH-AgNPs, a blue shift in the Q band was induced. The triplet lifetimes and quantum yields improved upon conjugation as compared to the phthalocyanines (Pc) alone. Complex 1.5 triplet lifetimes increased from 109 to 148 and triplet quantum yield from 0.65 to 0.86 upon conjugation. Fluorescence lifetimes and quantum yields decreased for the conjugates compared to the phthalocyanines alone, due to the quenching caused by the Ag NPs. The antimicrobial activity of the zinc phthalocyanines (complexes 1.3 and 1.5) and their conjugates against Escherichia coli was investigated. Only 1.3 and 1.5 complexes were investigated because of the availability of the sample. In general phthalocyanines showed increase in antibacterial activity with the increase in phthalocyanines concentration in the presence and absence of light. The Pc complexes and their Ag NP conjugates showed an increase in antibacterial activity, due to the synergistic effect afforded by Ag NP and Pcs. Improved antibacterial properties were obtained upon irradiation. 1.5-AgNPs had the highest antibacterial activity compared to 1.3-AgNPs conjugate; these results are in agreement with the photophysical behaviour. This work demonstrates improved photophysicochemical properties of low symm
- Full Text:
Photophysicochemical properties of aluminium phthalocyanine-platinum conjugates
- Authors: Malinga, Nduduzo Nkanyiso
- Date: 2013 , 2013-04-05
- Subjects: Phthalocyanines , Photochemistry , Photochemotherapy , Aluminium , Platinum , Nanoparticles , Cancer -- Photochemotherapy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4285 , http://hdl.handle.net/10962/d1002954 , Phthalocyanines , Photochemistry , Photochemotherapy , Aluminium , Platinum , Nanoparticles , Cancer -- Photochemotherapy
- Description: The combination of chemotherapy and photodynamic therapy was investigated by synthesis and characterization of octacarboxy phthalocyanine covalent conjugates with platinum complexes. This work presents the synthesis, characterization and photophysicochemical properties of aluminium (diaquaplatinum) octacarboxyphthalocyanine and aluminium (diammine) octacarboxyphthalocyanine. The conjugates were prepared by conjugating aluminium octacarboxy phthalocyanine with potassium tetrachloro platinate to yield aluminium tetrakis and trikis (diaquaplatinum) octacarboxy phthalocyanine. The aluminium octacarboxy phthalocyanine was also conjugated with cis-diamminedichloroplatinum to yield aluminium bis and tris (diaquaplatinum) octacarboxy phthalocyanine. From the characterization of the conjugates it was discovered that the aluminium (diaquaplatinum) octacarboxy phthalocyanine had formed platinum nanoparticles with the Pc acting as a capping agent. The triplet lifetimes decreased with the increasing number of platinum complexesconjugated to the Pc. The heavy atom effect improved the overall photophysicochemical properties.
- Full Text:
- Authors: Malinga, Nduduzo Nkanyiso
- Date: 2013 , 2013-04-05
- Subjects: Phthalocyanines , Photochemistry , Photochemotherapy , Aluminium , Platinum , Nanoparticles , Cancer -- Photochemotherapy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4285 , http://hdl.handle.net/10962/d1002954 , Phthalocyanines , Photochemistry , Photochemotherapy , Aluminium , Platinum , Nanoparticles , Cancer -- Photochemotherapy
- Description: The combination of chemotherapy and photodynamic therapy was investigated by synthesis and characterization of octacarboxy phthalocyanine covalent conjugates with platinum complexes. This work presents the synthesis, characterization and photophysicochemical properties of aluminium (diaquaplatinum) octacarboxyphthalocyanine and aluminium (diammine) octacarboxyphthalocyanine. The conjugates were prepared by conjugating aluminium octacarboxy phthalocyanine with potassium tetrachloro platinate to yield aluminium tetrakis and trikis (diaquaplatinum) octacarboxy phthalocyanine. The aluminium octacarboxy phthalocyanine was also conjugated with cis-diamminedichloroplatinum to yield aluminium bis and tris (diaquaplatinum) octacarboxy phthalocyanine. From the characterization of the conjugates it was discovered that the aluminium (diaquaplatinum) octacarboxy phthalocyanine had formed platinum nanoparticles with the Pc acting as a capping agent. The triplet lifetimes decreased with the increasing number of platinum complexesconjugated to the Pc. The heavy atom effect improved the overall photophysicochemical properties.
- Full Text:
Phylogeography and conservation of a newly identified galaxiid from the Joubertina area, South Africa
- Authors: Mataruse, Gamuchirai
- Date: 2013
- Subjects: Galaxiidae -- South Africa -- Joubertina , Phylogeography -- South Africa -- Joubertina , Galaxiidae -- Conservation -- South Africa -- Joubertina , Galaxiidae -- Effect of exotic animals on -- South Africa -- Joubertina , Galaxiidae -- Effect of habitat modification on -- South Africa -- Joubertina , Galaxiidae -- Genetics -- South Africa -- Joubertina , Galaxiidae -- Variation -- South Africa -- Joubertina , Galaxiidae -- Geographical distribution -- South Africa -- Joubertina
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5199 , http://hdl.handle.net/10962/d1003050 , Galaxiidae -- South Africa -- Joubertina , Phylogeography -- South Africa -- Joubertina , Galaxiidae -- Conservation -- South Africa -- Joubertina , Galaxiidae -- Effect of exotic animals on -- South Africa -- Joubertina , Galaxiidae -- Effect of habitat modification on -- South Africa -- Joubertina , Galaxiidae -- Genetics -- South Africa -- Joubertina , Galaxiidae -- Variation -- South Africa -- Joubertina , Galaxiidae -- Geographical distribution -- South Africa -- Joubertina
- Description: The dispersal of freshwater fishes in the Cape Floristic Region of South Africa has been attributed to river capture events and confluence of rivers during sea level regression. The role of low drainage divides and inter-basin water transfers have received less attention. A unique lineage of Galaxias zebratus (hereafter the Joubertina galaxias) occurs in two currently isolated river systems, the Gamtoos and Krom. The present study mapped the distribution of the Joubertina galaxias and used mitochondrial and nuclear DNA sequences to assess the processes that could have influenced its current distribution pattern. Analyses of both mitochondrial cytochrome ♭ and nuclear (S7) sequences revealed that observed genetic differentiation cannot be explained by isolation between the Gamtoos and Krom River systems. No genetic differentiation was found between the Krom River System and the Twee River (a tributary of the Gamtoos River System). Shallow genetic differentiation (0.4% for cytochrome ♭ and 0.3% for S7) was found between the Krom and the remaining populations in the Gamtoos River System. High levels of genetic structuring were observed within the Gamtoos River System with most tributaries having one or more unique alleles. Inter-basin dispersal during pluvial periods or recent human mediated translocation seems to be the most plausible explanations for presence of the Joubertina galaxias in the Krom River System. The present study also assessed the threats and habitat preferences of the Joubertina galaxias, and an evaluation of the conservation status of this lineage was done. The Joubertina galaxias is threatened mainly by alien fish invasion, habitat loss and loss of genetic diversity due to fragmentation of its populations. Due to its very restricted geographic range, small known population sizes and the intensity of threats to this lineage’s survival, this lineage has been assessed as Endangered. The lineage has a restricted Area of Occupancy (AOO) and Extent of Occurrence (EOO). The extent of occurrence has declined in all tributaries and is continuing to decline in all except two tributaries that are secure. The lineage may have had natural fragmentation among its populations, but recent threats have completely isolated the populations. The threats affect the lineage’s survival potential in the four tributaries which have small populations that are not presently viable. The densities observed for the Joubertina galaxias ranged from 0.16 - 1.3 fish /m² and the number of mature individuals for the whole population seems to be less than 2500 mature individuals. There is therefore a need for specific conservation actions to ensure the long-term survival of this unique lineage.
- Full Text:
- Authors: Mataruse, Gamuchirai
- Date: 2013
- Subjects: Galaxiidae -- South Africa -- Joubertina , Phylogeography -- South Africa -- Joubertina , Galaxiidae -- Conservation -- South Africa -- Joubertina , Galaxiidae -- Effect of exotic animals on -- South Africa -- Joubertina , Galaxiidae -- Effect of habitat modification on -- South Africa -- Joubertina , Galaxiidae -- Genetics -- South Africa -- Joubertina , Galaxiidae -- Variation -- South Africa -- Joubertina , Galaxiidae -- Geographical distribution -- South Africa -- Joubertina
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5199 , http://hdl.handle.net/10962/d1003050 , Galaxiidae -- South Africa -- Joubertina , Phylogeography -- South Africa -- Joubertina , Galaxiidae -- Conservation -- South Africa -- Joubertina , Galaxiidae -- Effect of exotic animals on -- South Africa -- Joubertina , Galaxiidae -- Effect of habitat modification on -- South Africa -- Joubertina , Galaxiidae -- Genetics -- South Africa -- Joubertina , Galaxiidae -- Variation -- South Africa -- Joubertina , Galaxiidae -- Geographical distribution -- South Africa -- Joubertina
- Description: The dispersal of freshwater fishes in the Cape Floristic Region of South Africa has been attributed to river capture events and confluence of rivers during sea level regression. The role of low drainage divides and inter-basin water transfers have received less attention. A unique lineage of Galaxias zebratus (hereafter the Joubertina galaxias) occurs in two currently isolated river systems, the Gamtoos and Krom. The present study mapped the distribution of the Joubertina galaxias and used mitochondrial and nuclear DNA sequences to assess the processes that could have influenced its current distribution pattern. Analyses of both mitochondrial cytochrome ♭ and nuclear (S7) sequences revealed that observed genetic differentiation cannot be explained by isolation between the Gamtoos and Krom River systems. No genetic differentiation was found between the Krom River System and the Twee River (a tributary of the Gamtoos River System). Shallow genetic differentiation (0.4% for cytochrome ♭ and 0.3% for S7) was found between the Krom and the remaining populations in the Gamtoos River System. High levels of genetic structuring were observed within the Gamtoos River System with most tributaries having one or more unique alleles. Inter-basin dispersal during pluvial periods or recent human mediated translocation seems to be the most plausible explanations for presence of the Joubertina galaxias in the Krom River System. The present study also assessed the threats and habitat preferences of the Joubertina galaxias, and an evaluation of the conservation status of this lineage was done. The Joubertina galaxias is threatened mainly by alien fish invasion, habitat loss and loss of genetic diversity due to fragmentation of its populations. Due to its very restricted geographic range, small known population sizes and the intensity of threats to this lineage’s survival, this lineage has been assessed as Endangered. The lineage has a restricted Area of Occupancy (AOO) and Extent of Occurrence (EOO). The extent of occurrence has declined in all tributaries and is continuing to decline in all except two tributaries that are secure. The lineage may have had natural fragmentation among its populations, but recent threats have completely isolated the populations. The threats affect the lineage’s survival potential in the four tributaries which have small populations that are not presently viable. The densities observed for the Joubertina galaxias ranged from 0.16 - 1.3 fish /m² and the number of mature individuals for the whole population seems to be less than 2500 mature individuals. There is therefore a need for specific conservation actions to ensure the long-term survival of this unique lineage.
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Planting season
- Authors: Ntabajyana, Sylvestre
- Date: 2013
- Subjects: South African poetry (English)--21st century , Creative writing (Higher education) , English language--Writing
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:5968 , http://hdl.handle.net/10962/d1002014
- Description: In this thesis I present a collection of semi-narrative poems about a rural Africa that is a place of folk-lore and tradition, but also a place of otherworldly, almost grotesque, incident. My characters are, similarly, range in type, from buskers, to guards, school-children, paupers and tycoons. Through the work a place that is both familiar and unknown, common-place and mysterious, emerge.
- Full Text:
- Authors: Ntabajyana, Sylvestre
- Date: 2013
- Subjects: South African poetry (English)--21st century , Creative writing (Higher education) , English language--Writing
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:5968 , http://hdl.handle.net/10962/d1002014
- Description: In this thesis I present a collection of semi-narrative poems about a rural Africa that is a place of folk-lore and tradition, but also a place of otherworldly, almost grotesque, incident. My characters are, similarly, range in type, from buskers, to guards, school-children, paupers and tycoons. Through the work a place that is both familiar and unknown, common-place and mysterious, emerge.
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Polyunsaturated fatty acid metabolism and effects on colon cancer cell biology in vitro.
- Authors: Bulcao, Candice
- Date: 2013
- Subjects: Unsaturated fatty acids , Unsaturated fatty acids in human nutrition , Colon (Anatomy)-- Cancer , Cancer -- Nutritional aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4137 , http://hdl.handle.net/10962/d1016128
- Description: Colon cancer is a leading cause of cancer related deaths worldwide. Lifestyle factors such as diet and exercise have been implicated as important agents in colon cancer development and progression. Epidemiological, in vivo and in vitro studies have found that n-3 polyunsaturated fatty acids (PUFAs) reduce colon carcinoma. The role of n-6 PUFAs remains a controversial topic, with studies indicating both promoting and preventing capabilities published. In order to better understand the effects of PUFAs on colon carcinoma, it is important to have an understanding of how they will be broken down in the body. During this study, in silico metabolism of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and arachidonic acid (AA) predicted the formation of hydroxy-, di-hydroxy- and epoxy-FAs. A gas chromatography-mass spectrometry method was developed and validated for the detection of these PUFAs and their cytochrome P450 (CYP) metabolites. A human liver microsomal system for the in vitro metabolism of EPA, DHA and AA was optimised in terms of microsomal and PUFA concentration. The system resulted in the metabolism of the positive control, lauric acid, to 12-hydroxy-lauric acid but was unable to metabolise the PUFAs of interest. EPA, DHA and AA reduced cell viability in the colon carcinoma cell lines SW480 and SW620 in the micromolar concentration range (25 – 200 μM). The CYP epoxidation metabolite of EPA, 17, 18-epoxyeicosatetraenoic acid (17, 18-EpETE) resulted in a significant reduction in SW480 cell viability relative to the parent compound at lower concentrations (25 and 50 μM). Annexin V apoptosis analysis revealed that EPA and 17, 18- EpETE did not result in apoptosis in SW480 cells at a concentration of 25 μM and over an incubation period of 24 hours. A significant reduction in reactive oxygen species production was seen in SW480 cells after incubation with 25 μM 17, 18-EpETE for 24 hours. EPA and 17, 18-EpETE were implicated in the reduction of colon cancer metastasis since they were able to reduce SW480 migration and anchorage independent cell growth. These results indicate that the dietary intake of EPA, DHA and AA may be beneficial to one’s health due to the negative effects that these PUFAs had on colon carcinoma. Future studies are needed to confirm these benefits and compare the effects of the PUFAs to their CYP-metabolites.
- Full Text:
- Authors: Bulcao, Candice
- Date: 2013
- Subjects: Unsaturated fatty acids , Unsaturated fatty acids in human nutrition , Colon (Anatomy)-- Cancer , Cancer -- Nutritional aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4137 , http://hdl.handle.net/10962/d1016128
- Description: Colon cancer is a leading cause of cancer related deaths worldwide. Lifestyle factors such as diet and exercise have been implicated as important agents in colon cancer development and progression. Epidemiological, in vivo and in vitro studies have found that n-3 polyunsaturated fatty acids (PUFAs) reduce colon carcinoma. The role of n-6 PUFAs remains a controversial topic, with studies indicating both promoting and preventing capabilities published. In order to better understand the effects of PUFAs on colon carcinoma, it is important to have an understanding of how they will be broken down in the body. During this study, in silico metabolism of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and arachidonic acid (AA) predicted the formation of hydroxy-, di-hydroxy- and epoxy-FAs. A gas chromatography-mass spectrometry method was developed and validated for the detection of these PUFAs and their cytochrome P450 (CYP) metabolites. A human liver microsomal system for the in vitro metabolism of EPA, DHA and AA was optimised in terms of microsomal and PUFA concentration. The system resulted in the metabolism of the positive control, lauric acid, to 12-hydroxy-lauric acid but was unable to metabolise the PUFAs of interest. EPA, DHA and AA reduced cell viability in the colon carcinoma cell lines SW480 and SW620 in the micromolar concentration range (25 – 200 μM). The CYP epoxidation metabolite of EPA, 17, 18-epoxyeicosatetraenoic acid (17, 18-EpETE) resulted in a significant reduction in SW480 cell viability relative to the parent compound at lower concentrations (25 and 50 μM). Annexin V apoptosis analysis revealed that EPA and 17, 18- EpETE did not result in apoptosis in SW480 cells at a concentration of 25 μM and over an incubation period of 24 hours. A significant reduction in reactive oxygen species production was seen in SW480 cells after incubation with 25 μM 17, 18-EpETE for 24 hours. EPA and 17, 18-EpETE were implicated in the reduction of colon cancer metastasis since they were able to reduce SW480 migration and anchorage independent cell growth. These results indicate that the dietary intake of EPA, DHA and AA may be beneficial to one’s health due to the negative effects that these PUFAs had on colon carcinoma. Future studies are needed to confirm these benefits and compare the effects of the PUFAs to their CYP-metabolites.
- Full Text:
Population size, demography and spatial ecology of cheetahs in the Timbavati Private Nature Reserve, South Africa
- Authors: Dyer, Siobhan Margaret
- Date: 2013
- Subjects: Timbavati Game Reserve (South Africa) Cheetah -- South Africa -- Timbavati Game Reserve Spatial behavior in animals Cheetah -- Behavior -- South Africa -- Timbavati Game Reserve Animal populations Population biology Rare mammals -- South Africa -- Timbavati Game Reserve Cheetah -- Effect of human beings on -- South Africa -- Timbavati Game Reserve
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5608 , http://hdl.handle.net/10962/d1002058
- Description: The cheetah (Acinonyx jubatus) has experienced a drastic decline in numbers over the last 20 years globally and is currently listed as vulnerable by the International Union for the Conservation of Nature (IUCN). In South Africa, there are only an estimated 763 free-ranging cheetahs and conflict with humans is arguably the most significant reason for this low number. The aim of my study was to determine the population size and demographic characteristics of the cheetah population within the Timbavati Private Nature Reserve (TPNR), South Africa, and to contribute to a better understanding of cheetah space use and habitat selection. The research was conducted on TPNR between November 2009 and June 2011 and I used a photographic survey to assess cheetah population size and demographic characteristics. Location data was obtained by collaring two adult male cheetahs with GPS/GSM collars and ad hoc sightings data from across the reserve for an adult female with cubs and three adolescent females. A relatively high minimum population density of 4.46 cheetahs/100km² was estimated, signifying a relatively healthy cheetah population. The sex ratio data indicated a higher male to female ratio and an average litter size of three cubs. The relatively high cub survival rate and density is promising in terms of the status of species within the area, as the data denote the success and potential persistence of the species. Cheetah home ranges varied between 20.97km² for the female with cubs and 659.65km² for the younger collared male. Season did not appear to be a determining factor in terms of home range sizes for the three social groups within the TPNR. However, the males did show a slight increase in their home range sizes during the dry season when resources where presumably more widespread. My results indicate that the cheetah is an adaptable species, flexible in behaviour and able to tolerate a variety of habitat types. Such knowledge is fundamental for planning and implementing the effective management and conservation of cheetahs in South Africa.
- Full Text:
- Authors: Dyer, Siobhan Margaret
- Date: 2013
- Subjects: Timbavati Game Reserve (South Africa) Cheetah -- South Africa -- Timbavati Game Reserve Spatial behavior in animals Cheetah -- Behavior -- South Africa -- Timbavati Game Reserve Animal populations Population biology Rare mammals -- South Africa -- Timbavati Game Reserve Cheetah -- Effect of human beings on -- South Africa -- Timbavati Game Reserve
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5608 , http://hdl.handle.net/10962/d1002058
- Description: The cheetah (Acinonyx jubatus) has experienced a drastic decline in numbers over the last 20 years globally and is currently listed as vulnerable by the International Union for the Conservation of Nature (IUCN). In South Africa, there are only an estimated 763 free-ranging cheetahs and conflict with humans is arguably the most significant reason for this low number. The aim of my study was to determine the population size and demographic characteristics of the cheetah population within the Timbavati Private Nature Reserve (TPNR), South Africa, and to contribute to a better understanding of cheetah space use and habitat selection. The research was conducted on TPNR between November 2009 and June 2011 and I used a photographic survey to assess cheetah population size and demographic characteristics. Location data was obtained by collaring two adult male cheetahs with GPS/GSM collars and ad hoc sightings data from across the reserve for an adult female with cubs and three adolescent females. A relatively high minimum population density of 4.46 cheetahs/100km² was estimated, signifying a relatively healthy cheetah population. The sex ratio data indicated a higher male to female ratio and an average litter size of three cubs. The relatively high cub survival rate and density is promising in terms of the status of species within the area, as the data denote the success and potential persistence of the species. Cheetah home ranges varied between 20.97km² for the female with cubs and 659.65km² for the younger collared male. Season did not appear to be a determining factor in terms of home range sizes for the three social groups within the TPNR. However, the males did show a slight increase in their home range sizes during the dry season when resources where presumably more widespread. My results indicate that the cheetah is an adaptable species, flexible in behaviour and able to tolerate a variety of habitat types. Such knowledge is fundamental for planning and implementing the effective management and conservation of cheetahs in South Africa.
- Full Text:
Portfolio
- Hogge, Quentin Edward Somerville
- Authors: Hogge, Quentin Edward Somerville
- Date: 2013
- Subjects: Poetry , Post-apartheid , Environment , South African poetry (English) -- 21st century , Creative writing (Higher education) , English language -- Writing
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:5963 , http://hdl.handle.net/10962/d1001813
- Description: My initial intention is to try to show how, as a poet in South Africa, I suffer from a creative identity crisis. I am a white English-speaking male. I live surrounded by isiXhosa-speaking people. Is my poetry, or will my poetry be, relevant in the ‘New’ South Africa? Is English, the language of the colonial oppressors, the appropriate medium in the post-apartheid milieu? Will my subject matter be relevant? These questions and my attempts at answering them, form the basis of the poetry and the portfolio that accompanies the poems. My absorption with finding a creative ‘voice’, my concerns with the environment and a questioning of what post-apartheid poetry should write about all seem a bit Quixotic, especially to me! But at another level, they are deeply serious. (p. 5.)
- Full Text:
- Authors: Hogge, Quentin Edward Somerville
- Date: 2013
- Subjects: Poetry , Post-apartheid , Environment , South African poetry (English) -- 21st century , Creative writing (Higher education) , English language -- Writing
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:5963 , http://hdl.handle.net/10962/d1001813
- Description: My initial intention is to try to show how, as a poet in South Africa, I suffer from a creative identity crisis. I am a white English-speaking male. I live surrounded by isiXhosa-speaking people. Is my poetry, or will my poetry be, relevant in the ‘New’ South Africa? Is English, the language of the colonial oppressors, the appropriate medium in the post-apartheid milieu? Will my subject matter be relevant? These questions and my attempts at answering them, form the basis of the poetry and the portfolio that accompanies the poems. My absorption with finding a creative ‘voice’, my concerns with the environment and a questioning of what post-apartheid poetry should write about all seem a bit Quixotic, especially to me! But at another level, they are deeply serious. (p. 5.)
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Preliminary normative indications for Xhosa speaking unskilled workers on the Rey-Osterrieth complex figure test
- De Kock, Heinrich Karl Theodor
- Authors: De Kock, Heinrich Karl Theodor
- Date: 2013 , 2013-08-26
- Subjects: Rey-Osterrieth Complex Figure Test Educational tests and measurements Xhosa (African people) -- Education Neuropsychological tests -- Cross-cultural studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3130 , http://hdl.handle.net/10962/d1006476
- Description: The aim of this study was to establish preliminary normative indications for Rey-Osterrieth Complex Figure test administered in English on a non-clinical population of Xhosa, unskilled workers (N = 33). The population has a history of relatively poor quality education and has received no tertiary education. The sample was stratified into two age grouping (18 – 29 and 30 – 40 years). Both sex and level of education were equally distributed within these age groupings. Within-sample statistical comparisons indicated no significant sex effect was present for any of the trials (Copy, IR or DR). Similarly, no significant age effect was present in the Copy trial. Significant age effects were observed for both recall trials (IR and DR). The local sample’s mean performance was descriptively and statistically compared to demographically equivalent nonlocal normative studies. Excluding an illiterate Columbian sample’s performance, the local sample performed significantly lower than all other available normative populations. Lastly, the local sample performed significantly lower than scores derived from a meta-analysis of normative indications in respect of educationally advantaged westernized groups for all three trials (p = .000 in all instances). These results assert the indispensable need for, and use of, culturally appropriate normative datasets in contemporary South African psychological assessments. Equally, these findings serve to highlight the significant influence of quality of education on cognitive test performance, being a critical socio-cultural variable that needs to be taken into consideration for norming purposes.
- Full Text:
- Authors: De Kock, Heinrich Karl Theodor
- Date: 2013 , 2013-08-26
- Subjects: Rey-Osterrieth Complex Figure Test Educational tests and measurements Xhosa (African people) -- Education Neuropsychological tests -- Cross-cultural studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3130 , http://hdl.handle.net/10962/d1006476
- Description: The aim of this study was to establish preliminary normative indications for Rey-Osterrieth Complex Figure test administered in English on a non-clinical population of Xhosa, unskilled workers (N = 33). The population has a history of relatively poor quality education and has received no tertiary education. The sample was stratified into two age grouping (18 – 29 and 30 – 40 years). Both sex and level of education were equally distributed within these age groupings. Within-sample statistical comparisons indicated no significant sex effect was present for any of the trials (Copy, IR or DR). Similarly, no significant age effect was present in the Copy trial. Significant age effects were observed for both recall trials (IR and DR). The local sample’s mean performance was descriptively and statistically compared to demographically equivalent nonlocal normative studies. Excluding an illiterate Columbian sample’s performance, the local sample performed significantly lower than all other available normative populations. Lastly, the local sample performed significantly lower than scores derived from a meta-analysis of normative indications in respect of educationally advantaged westernized groups for all three trials (p = .000 in all instances). These results assert the indispensable need for, and use of, culturally appropriate normative datasets in contemporary South African psychological assessments. Equally, these findings serve to highlight the significant influence of quality of education on cognitive test performance, being a critical socio-cultural variable that needs to be taken into consideration for norming purposes.
- Full Text:
Profiling for volatile compounds in the Kgalagadi desert truffle
- Authors: Bogopa, Juda
- Date: 2013
- Subjects: Desert plants -- Botswana -- Kgalagadi District Supercritical fluid extraction Gas chromatography Mass spectrometry Tuberaceae -- Analysis -- Botswana -- Kgalagadi District Truffles -- Analysis -- Botswana -- Kgalagadi District
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4280 , http://hdl.handle.net/10962/d1002006
- Description: The thesis focuses on ‘green’ sample preparation techniques that utilise minimal or no organic solvents thereby producing negligible volumes of organic waste, to ensure safety both to user and the environment. Volatile compounds were extracted and pre-concentrated from Kgalagadi desert truffles (kalaharituber) by headspace solid phase microextraction (HSSPME) and supercritical fluid extraction (SFE). PHWE was employed for the extraction of amino acids and fatty acids. Subsequent analysis of volatile compounds was carried out by gas chromatography coupled with mass spectrometry. Four types of HS-SPME fibers (PDMS 100 μm, PDMS 7 μm, Polyacrylate 85 μm, CAR/DVB/PDMS 50/30 μm) were evaluated. A total of 24 volatile compounds with a molecular weight range from 110 to 354, the most prominent peak being 2-t-Butyl-2,3-dimethyl-3-buten-1-ol (C₁₀H₂₀O, MW 156) were detected after sampling with a PDMS 100 μm fiber. Less volatile compounds were detected after SFE with CO2. A total of 16 amino acids were identified while 17 fatty acids (MW from 132.12 to 367.49) were also identified. The characteristic profile of the Kgalagadi desert truffle was found to contain mainly fatty acid methyl esters and unsaturated aliphatic hydrocarbons. The most prominent compound peaks identified were; 2-t-butyl-2,3-dimethyl- 3-buten-1-ol, disulfide, ethyl benzoic acid 2-4-dhydroxy-3,6-dimethyl-methyl ester, 8,11- octadecanoic acid methyl ester, benzoic acid, 2,4-dihydroxy-3,6-dimethyl-methyl ester, isoquinoline, 1 butyl-3,4-dihydro and 3-heptanone, 6 methyl. Optimization results indicated that fresh slices from the heart of truffles were the best to use for HS-SPME-GCMS volatile compound analysis as they showed a higher sensitivity
- Full Text:
- Authors: Bogopa, Juda
- Date: 2013
- Subjects: Desert plants -- Botswana -- Kgalagadi District Supercritical fluid extraction Gas chromatography Mass spectrometry Tuberaceae -- Analysis -- Botswana -- Kgalagadi District Truffles -- Analysis -- Botswana -- Kgalagadi District
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4280 , http://hdl.handle.net/10962/d1002006
- Description: The thesis focuses on ‘green’ sample preparation techniques that utilise minimal or no organic solvents thereby producing negligible volumes of organic waste, to ensure safety both to user and the environment. Volatile compounds were extracted and pre-concentrated from Kgalagadi desert truffles (kalaharituber) by headspace solid phase microextraction (HSSPME) and supercritical fluid extraction (SFE). PHWE was employed for the extraction of amino acids and fatty acids. Subsequent analysis of volatile compounds was carried out by gas chromatography coupled with mass spectrometry. Four types of HS-SPME fibers (PDMS 100 μm, PDMS 7 μm, Polyacrylate 85 μm, CAR/DVB/PDMS 50/30 μm) were evaluated. A total of 24 volatile compounds with a molecular weight range from 110 to 354, the most prominent peak being 2-t-Butyl-2,3-dimethyl-3-buten-1-ol (C₁₀H₂₀O, MW 156) were detected after sampling with a PDMS 100 μm fiber. Less volatile compounds were detected after SFE with CO2. A total of 16 amino acids were identified while 17 fatty acids (MW from 132.12 to 367.49) were also identified. The characteristic profile of the Kgalagadi desert truffle was found to contain mainly fatty acid methyl esters and unsaturated aliphatic hydrocarbons. The most prominent compound peaks identified were; 2-t-butyl-2,3-dimethyl- 3-buten-1-ol, disulfide, ethyl benzoic acid 2-4-dhydroxy-3,6-dimethyl-methyl ester, 8,11- octadecanoic acid methyl ester, benzoic acid, 2,4-dihydroxy-3,6-dimethyl-methyl ester, isoquinoline, 1 butyl-3,4-dihydro and 3-heptanone, 6 methyl. Optimization results indicated that fresh slices from the heart of truffles were the best to use for HS-SPME-GCMS volatile compound analysis as they showed a higher sensitivity
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Psychodynamic case formulations : reflections of a neophyte therapist's experiences of how developing and using a psychodynamic formulation may have influenced treatment?
- Authors: Tebbutt, Hayley Lynne
- Date: 2013 , 2013-11-04
- Subjects: Psychodynamic psychotherapy Psychiatry -- Case formulation Eating disorders
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3133 , http://hdl.handle.net/10962/d1006812
- Description: Although it is generally acknowledged and accepted that case formulations are useful in psychotherapy treatment, there is significantly little research illustrating how case formulations are useful in treatment. Research also suggests that case formulations are seldom used in practice after initial training (Eells, 1997; Sim, Gwee, & Bateman, 2005). This research was premised on a particular case study which appeared to highlight shifts in psychotherapy treatment in the sessions directly after the writing or revising of the case formulation, thus prompting the inquiry into the influence of the case formulation on therapeutic work. The research utilised a qualitative methodology and focused on a single case which was a 19 year old university student who expressed a problem with binge eating. The data was drawn from five original and revised case formulations. The participant was seen for 27 therapy sessions, over which time five case formulations were developed and revised. The findings in this study highlight the process of how a psychodynamic case formulation can influence therapeutic work, as reflected in three broad themes of adherence to the case formulation, the confidence of the therapist, and using the formulation as an intervention. The study contributes to arguments for the revival of the case formulation as a necessary therapeutic tool. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Authors: Tebbutt, Hayley Lynne
- Date: 2013 , 2013-11-04
- Subjects: Psychodynamic psychotherapy Psychiatry -- Case formulation Eating disorders
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3133 , http://hdl.handle.net/10962/d1006812
- Description: Although it is generally acknowledged and accepted that case formulations are useful in psychotherapy treatment, there is significantly little research illustrating how case formulations are useful in treatment. Research also suggests that case formulations are seldom used in practice after initial training (Eells, 1997; Sim, Gwee, & Bateman, 2005). This research was premised on a particular case study which appeared to highlight shifts in psychotherapy treatment in the sessions directly after the writing or revising of the case formulation, thus prompting the inquiry into the influence of the case formulation on therapeutic work. The research utilised a qualitative methodology and focused on a single case which was a 19 year old university student who expressed a problem with binge eating. The data was drawn from five original and revised case formulations. The participant was seen for 27 therapy sessions, over which time five case formulations were developed and revised. The findings in this study highlight the process of how a psychodynamic case formulation can influence therapeutic work, as reflected in three broad themes of adherence to the case formulation, the confidence of the therapist, and using the formulation as an intervention. The study contributes to arguments for the revival of the case formulation as a necessary therapeutic tool. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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Real options valuation for South African nuclear waste management using a fuzzy mathematical approach
- Authors: Montsho, Obakeng Johannes
- Date: 2013 , 2013-06-06
- Subjects: Fuzzy mathematics , Real options (Finance) , Fuzzy sets , Business mathematics , Radioactive waste disposal -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5398 , http://hdl.handle.net/10962/d1003051 , Fuzzy mathematics , Real options (Finance) , Fuzzy sets , Business mathematics , Radioactive waste disposal -- South Africa
- Description: The feasibility of capital projects in an uncertain world can be determined in several ways. One of these methods is real options valuation which arose from financial option valuation theory. On the other hand fuzzy set theory was developed as a mathematical framework to capture uncertainty in project management. The valuation of real options using fuzzy numbers represents an important refinement to determining capital projects' feasibility using the real options approach. The aim of this study is to determine whether the deferral of the decommissioning time (by a decade) of an electricity-generating nuclear plant in South Africa increases decommissioning costs. Using the fuzzy binomial approach, decommissioning costs increase when decommissioning is postponed by a decade whereas use of the fuzzy Black-Scholes approach yields the opposite result. A python code was developed to assist in the computation of fuzzy binomial trees required in our study and the results of the program are incorporated in this thesis. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Authors: Montsho, Obakeng Johannes
- Date: 2013 , 2013-06-06
- Subjects: Fuzzy mathematics , Real options (Finance) , Fuzzy sets , Business mathematics , Radioactive waste disposal -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5398 , http://hdl.handle.net/10962/d1003051 , Fuzzy mathematics , Real options (Finance) , Fuzzy sets , Business mathematics , Radioactive waste disposal -- South Africa
- Description: The feasibility of capital projects in an uncertain world can be determined in several ways. One of these methods is real options valuation which arose from financial option valuation theory. On the other hand fuzzy set theory was developed as a mathematical framework to capture uncertainty in project management. The valuation of real options using fuzzy numbers represents an important refinement to determining capital projects' feasibility using the real options approach. The aim of this study is to determine whether the deferral of the decommissioning time (by a decade) of an electricity-generating nuclear plant in South Africa increases decommissioning costs. Using the fuzzy binomial approach, decommissioning costs increase when decommissioning is postponed by a decade whereas use of the fuzzy Black-Scholes approach yields the opposite result. A python code was developed to assist in the computation of fuzzy binomial trees required in our study and the results of the program are incorporated in this thesis. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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Remembering the traumatic past
- Authors: Tarr, Amie
- Date: 2013
- Subjects: Psychic trauma in art , Memory in art -- South Africa
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2431 , http://hdl.handle.net/10962/d1004216 , Psychic trauma in art , Memory in art -- South Africa
- Description: In this thesis, I explore my personal family history in relation to the difficulties and challenges raised when representing a trauma in the past. My focus was the Blaaukraantz Bridge railway disaster of 1911, where my great great grandfather, Paul Tarr, was among the 29 victims. The links between my personal family history and the disaster are explored in my art practice. In the mini thesis, I unpack theoretical concerns surrounding memory, loss, and representation of past trauma by examining selected works by Christian Boltanski, Rachel Whiteread and Doris Salcedo. I do not endeavour to provide new insights about early twentieth-century history but instead to engage with different ways of forming narratives about the past. Memory as an alternative form of history writing is the key concept in this thesis in that personal memory and testimony provides an integral perception of the past and important details that would not appear in history texts or other factual forms of writing the past. In this thesis I unpack this issue in relation to my own art practice.
- Full Text:
- Authors: Tarr, Amie
- Date: 2013
- Subjects: Psychic trauma in art , Memory in art -- South Africa
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2431 , http://hdl.handle.net/10962/d1004216 , Psychic trauma in art , Memory in art -- South Africa
- Description: In this thesis, I explore my personal family history in relation to the difficulties and challenges raised when representing a trauma in the past. My focus was the Blaaukraantz Bridge railway disaster of 1911, where my great great grandfather, Paul Tarr, was among the 29 victims. The links between my personal family history and the disaster are explored in my art practice. In the mini thesis, I unpack theoretical concerns surrounding memory, loss, and representation of past trauma by examining selected works by Christian Boltanski, Rachel Whiteread and Doris Salcedo. I do not endeavour to provide new insights about early twentieth-century history but instead to engage with different ways of forming narratives about the past. Memory as an alternative form of history writing is the key concept in this thesis in that personal memory and testimony provides an integral perception of the past and important details that would not appear in history texts or other factual forms of writing the past. In this thesis I unpack this issue in relation to my own art practice.
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Responses to the linked stressors of climate change and HIV/AIDS amongst vulnerable rural households in the Eastern Cape, South Africa
- Authors: Clarke, Caryn Lee
- Date: 2013
- Subjects: Climatic changes -- South Africa -- Eastern Cape Climatic changes -- Health aspects -- South Africa -- Eastern Cape Climatic changes -- Economic aspects -- South Africa -- Eastern Cape HIV infections -- Economic aspects -- South Africa -- Eastern Cape AIDS (Disease) -- Economic aspects -- South Africa -- Eastern Cape HIV infections -- Social aspects -- South Africa -- Eastern Cape AIDS (Disease) -- Social aspects -- South Africa -- Eastern Cape Poverty -- Social aspects -- South Africa -- Eastern Cape Income -- South Africa -- Eastern Cape Human capital -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4732 , http://hdl.handle.net/10962/d1003818
- Description: Climate change and the HIV/AIDS epidemic are two of the most critical long-term global challenges, especially for Africa and even more so Southern Africa. There is great concern that the poor will be unable to adapt to the impacts of climate variability and change while HIV/AIDS will exacerbate the impacts of such stressors and deepen the insecurities of many communities already affected by this disease. Studies that consider the interlinked effects of climate change and HIV/AIDS along with other multiple stressors are increasingly needed. This study, located in two rural communities in the Eastern Cape Province of South Africa, namely Lesseyton and Willowvale, assessed the responses of vulnerable households to the linked shocks and stressors of climate change and HIV/AIDS. This involved assessing, through household surveys, life history interviews and Participatory Learning and Action (PLA), the way in which multiple stressors interacted and affected vulnerable households, the way in which these households responded to and coped with such shocks and stressors, and the barriers which prevented them from coping and adapting effectively. Unemployment emerged as the dominant stress amongst households. The lack of development and having too few opportunities for employment has limited vulnerable households from being able to invest in assets, such as education or farming equipment. This, in combination with the impacts of increased food and water insecurity from recent drought, has created an extremely vulnerable environment for these households. They rely largely on two important safety-nets, namely social capital and the use of natural and cultivated resources; however the latter has been limited due to the impacts of water scarcity and an inability to farm. It was evident that there was little planned long-term adaptation amongst households and from government. Maladaptive short-term coping strategies, such numerous household members depending on one social grant and transactional sex, were too often relied upon, and although they may have helped relieve the stress of shocks momentarily, they did not provide for the long-term well-being of individuals and households. Poor communication and capacity between the different levels of government and between the government (especially at the local level) and the two rural communities has created an environment full of uncertainty and lacking in advocacy. Local government needs increased human, informational, and financial capacity and a clear delegation of responsibilities amongst the different departments in order for the two communities to benefit from the implementation of support strategies. There is also a great need for educational programmes and capacity development within the two rural communities, particularly based on improved coping and longer-term adaptation strategies in response to climate change in order for households to better prepare themselves for the future.
- Full Text:
- Authors: Clarke, Caryn Lee
- Date: 2013
- Subjects: Climatic changes -- South Africa -- Eastern Cape Climatic changes -- Health aspects -- South Africa -- Eastern Cape Climatic changes -- Economic aspects -- South Africa -- Eastern Cape HIV infections -- Economic aspects -- South Africa -- Eastern Cape AIDS (Disease) -- Economic aspects -- South Africa -- Eastern Cape HIV infections -- Social aspects -- South Africa -- Eastern Cape AIDS (Disease) -- Social aspects -- South Africa -- Eastern Cape Poverty -- Social aspects -- South Africa -- Eastern Cape Income -- South Africa -- Eastern Cape Human capital -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4732 , http://hdl.handle.net/10962/d1003818
- Description: Climate change and the HIV/AIDS epidemic are two of the most critical long-term global challenges, especially for Africa and even more so Southern Africa. There is great concern that the poor will be unable to adapt to the impacts of climate variability and change while HIV/AIDS will exacerbate the impacts of such stressors and deepen the insecurities of many communities already affected by this disease. Studies that consider the interlinked effects of climate change and HIV/AIDS along with other multiple stressors are increasingly needed. This study, located in two rural communities in the Eastern Cape Province of South Africa, namely Lesseyton and Willowvale, assessed the responses of vulnerable households to the linked shocks and stressors of climate change and HIV/AIDS. This involved assessing, through household surveys, life history interviews and Participatory Learning and Action (PLA), the way in which multiple stressors interacted and affected vulnerable households, the way in which these households responded to and coped with such shocks and stressors, and the barriers which prevented them from coping and adapting effectively. Unemployment emerged as the dominant stress amongst households. The lack of development and having too few opportunities for employment has limited vulnerable households from being able to invest in assets, such as education or farming equipment. This, in combination with the impacts of increased food and water insecurity from recent drought, has created an extremely vulnerable environment for these households. They rely largely on two important safety-nets, namely social capital and the use of natural and cultivated resources; however the latter has been limited due to the impacts of water scarcity and an inability to farm. It was evident that there was little planned long-term adaptation amongst households and from government. Maladaptive short-term coping strategies, such numerous household members depending on one social grant and transactional sex, were too often relied upon, and although they may have helped relieve the stress of shocks momentarily, they did not provide for the long-term well-being of individuals and households. Poor communication and capacity between the different levels of government and between the government (especially at the local level) and the two rural communities has created an environment full of uncertainty and lacking in advocacy. Local government needs increased human, informational, and financial capacity and a clear delegation of responsibilities amongst the different departments in order for the two communities to benefit from the implementation of support strategies. There is also a great need for educational programmes and capacity development within the two rural communities, particularly based on improved coping and longer-term adaptation strategies in response to climate change in order for households to better prepare themselves for the future.
- Full Text:
Restitution : seeing past loss and abandonment
- Authors: Greenway, Paul Wayne
- Date: 2013
- Subjects: Digitally printed materials Bereavement in art
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2389 , http://hdl.handle.net/10962/d1001579
- Description: This dissertation is concerned with loss and abandonment, and together with the practical component, titled Restitution, forms part of a Master of Fine Art degree submission. Both loss and abandonment can take many forms, from the straightforward deterioration, departure or removal of objects to the more complex deterioration of memory, responsibility and dignity. It seems though, that the question, “What has been lost?” is one that is always asked once it is too late. The loss becomes irretrievable and one is left only with fragments and traces. In Chapter 1 issues of liminality and the precariousness of being between states is addressed. Dignity of the ‘other’, in this case the deceased pauper, is interrogated especially with reference to complicity, forensic investigation and the forensic aesthetic. Chapter 2 outlines photographic representation, with attention given to posthumous portraiture, the punctum and memory in the service of permanence and authenticity. Chapter 3 considers the ambition and purpose of the artist through a critique centred on contemporary photographic artist, Sally Mann. Throughout the thesis and exhibition, I am concerned with loss as it relates physically to objects. Metaphorically, I investigate loss and abandonment in relation to dignity and responsibility. In so doing I view death as being the ultimate form of loss, as there is physical loss of the body, as one part of the whole that makes up ‘the person’, as well as the psychological and emotional loss that attends the passing of life. The delayed burial of the deceased therefore is seen to be evidence of abandonment at its extreme. I end by positioning my conclusion around a stop animation series in which I dug a grave and buried a pauper at Mayfield cemetery.
- Full Text:
- Authors: Greenway, Paul Wayne
- Date: 2013
- Subjects: Digitally printed materials Bereavement in art
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2389 , http://hdl.handle.net/10962/d1001579
- Description: This dissertation is concerned with loss and abandonment, and together with the practical component, titled Restitution, forms part of a Master of Fine Art degree submission. Both loss and abandonment can take many forms, from the straightforward deterioration, departure or removal of objects to the more complex deterioration of memory, responsibility and dignity. It seems though, that the question, “What has been lost?” is one that is always asked once it is too late. The loss becomes irretrievable and one is left only with fragments and traces. In Chapter 1 issues of liminality and the precariousness of being between states is addressed. Dignity of the ‘other’, in this case the deceased pauper, is interrogated especially with reference to complicity, forensic investigation and the forensic aesthetic. Chapter 2 outlines photographic representation, with attention given to posthumous portraiture, the punctum and memory in the service of permanence and authenticity. Chapter 3 considers the ambition and purpose of the artist through a critique centred on contemporary photographic artist, Sally Mann. Throughout the thesis and exhibition, I am concerned with loss as it relates physically to objects. Metaphorically, I investigate loss and abandonment in relation to dignity and responsibility. In so doing I view death as being the ultimate form of loss, as there is physical loss of the body, as one part of the whole that makes up ‘the person’, as well as the psychological and emotional loss that attends the passing of life. The delayed burial of the deceased therefore is seen to be evidence of abandonment at its extreme. I end by positioning my conclusion around a stop animation series in which I dug a grave and buried a pauper at Mayfield cemetery.
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Rural livelihoods and adherence to HIV and AIDS antiretroviral therapy in Chivanhu Settlement, Nemamwa Village in Masvingo District, Zimbabwe
- Authors: Wapinduka, Tendai
- Date: 2013
- Subjects: AIDS (Disease) -- Social aspects -- Zimbabwe -- Masvingo Rural development -- Zimbabwe -- Masvingo AIDS (Disease) -- Treatment -- Zimbabwe -- Masvingo Antiretroviral agents -- Zimbabwe -- Masvingo
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3336 , http://hdl.handle.net/10962/d1003743
- Description: The Human Immunodeficiency Virus (HIV) and Acquired Immuno Deficiency Syndrome (AIDS) epidemic has had massive detrimental impacts on rural communities across Africa including in Zimbabwe. In response to the HIV and AIDS epidemic, the government of Zimbabwe has developed and adopted comprehensive programmes to address HIV and AIDS prevention, care and support. One of the critical components of these programmes relates specifically to treatment of the HIV infected given that HIV and AIDS is increasingly seen as a manageable threatening disease. However the success and effectiveness of the treatment regimen (involving antiretroviral drugs or ARVs) is dependent heavily on complete adherence to the rigid and complex regimens. It is against this background that this thesis studies a particular rural community in Zimbabwe called Chivanhu (in Masvingo Province) in terms of the relationship between rural livelihoods and HIV and AIDS (particularly HIV treatment and treatment adherence). Unlike other rural communities (notably in communal areas), Chivanhu is an informal and unstable community with a turbulent history. Most rural studies of HIV and AIDS in Zimbabwe and elsewhere in the region have focused on well-established and stable communities in which agricultural production is still of some significance. In such communities, the impact of HIV and AIDS on livelihoods is severe but, in more informal settlements, the vulnerability of households to the epidemic (and challenges pertaining to treatment adherence) is even more pronounced. Using a rural livelihoods framework, this thesis seeks to identify, understand and analyse the conditions which shape levels of adherence to HIV and AIDS in the informalsettlement of Chivanhu in Zimbabwe.
- Full Text:
- Authors: Wapinduka, Tendai
- Date: 2013
- Subjects: AIDS (Disease) -- Social aspects -- Zimbabwe -- Masvingo Rural development -- Zimbabwe -- Masvingo AIDS (Disease) -- Treatment -- Zimbabwe -- Masvingo Antiretroviral agents -- Zimbabwe -- Masvingo
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3336 , http://hdl.handle.net/10962/d1003743
- Description: The Human Immunodeficiency Virus (HIV) and Acquired Immuno Deficiency Syndrome (AIDS) epidemic has had massive detrimental impacts on rural communities across Africa including in Zimbabwe. In response to the HIV and AIDS epidemic, the government of Zimbabwe has developed and adopted comprehensive programmes to address HIV and AIDS prevention, care and support. One of the critical components of these programmes relates specifically to treatment of the HIV infected given that HIV and AIDS is increasingly seen as a manageable threatening disease. However the success and effectiveness of the treatment regimen (involving antiretroviral drugs or ARVs) is dependent heavily on complete adherence to the rigid and complex regimens. It is against this background that this thesis studies a particular rural community in Zimbabwe called Chivanhu (in Masvingo Province) in terms of the relationship between rural livelihoods and HIV and AIDS (particularly HIV treatment and treatment adherence). Unlike other rural communities (notably in communal areas), Chivanhu is an informal and unstable community with a turbulent history. Most rural studies of HIV and AIDS in Zimbabwe and elsewhere in the region have focused on well-established and stable communities in which agricultural production is still of some significance. In such communities, the impact of HIV and AIDS on livelihoods is severe but, in more informal settlements, the vulnerability of households to the epidemic (and challenges pertaining to treatment adherence) is even more pronounced. Using a rural livelihoods framework, this thesis seeks to identify, understand and analyse the conditions which shape levels of adherence to HIV and AIDS in the informalsettlement of Chivanhu in Zimbabwe.
- Full Text:
Search engine poisoning and its prevalence in modern search engines
- Authors: Blaauw, Pieter
- Date: 2013
- Subjects: Web search engines Internet searching World Wide Web Malware (Computer software) Computer viruses Rootkits (Computer software) Spyware (Computer software)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4572 , http://hdl.handle.net/10962/d1002037
- Description: The prevalence of Search Engine Poisoning in trending topics and popular search terms on the web within search engines is investigated. Search Engine Poisoning is the act of manipulating search engines in order to display search results from websites infected with malware. Research done between February and August 2012, using both manual and automated techniques, shows us how easily the criminal element manages to insert malicious content into web pages related to popular search terms within search engines. In order to provide the reader with a clear overview and understanding of the motives and the methods of the operators of Search Engine Poisoning campaigns, an in-depth review of automated and semi-automated web exploit kits is done, as well as looking into the motives for running these campaigns. Three high profile case studies are examined, and the various Search Engine Poisoning campaigns associated with these case studies are discussed in detail to the reader. From February to August 2012, data was collected from the top trending topics on Google’s search engine along with the top listed sites related to these topics, and then passed through various automated tools to discover if these results have been infiltrated by the operators of Search Engine Poisoning campaings, and the results of these automated scans are then discussed in detail. During the research period, manual searching for Search Engine Poisoning campaigns was also done, using high profile news events and popular search terms. These results are analysed in detail to determine the methods of attack, the purpose of the attack and the parties behind it
- Full Text:
- Authors: Blaauw, Pieter
- Date: 2013
- Subjects: Web search engines Internet searching World Wide Web Malware (Computer software) Computer viruses Rootkits (Computer software) Spyware (Computer software)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4572 , http://hdl.handle.net/10962/d1002037
- Description: The prevalence of Search Engine Poisoning in trending topics and popular search terms on the web within search engines is investigated. Search Engine Poisoning is the act of manipulating search engines in order to display search results from websites infected with malware. Research done between February and August 2012, using both manual and automated techniques, shows us how easily the criminal element manages to insert malicious content into web pages related to popular search terms within search engines. In order to provide the reader with a clear overview and understanding of the motives and the methods of the operators of Search Engine Poisoning campaigns, an in-depth review of automated and semi-automated web exploit kits is done, as well as looking into the motives for running these campaigns. Three high profile case studies are examined, and the various Search Engine Poisoning campaigns associated with these case studies are discussed in detail to the reader. From February to August 2012, data was collected from the top trending topics on Google’s search engine along with the top listed sites related to these topics, and then passed through various automated tools to discover if these results have been infiltrated by the operators of Search Engine Poisoning campaings, and the results of these automated scans are then discussed in detail. During the research period, manual searching for Search Engine Poisoning campaigns was also done, using high profile news events and popular search terms. These results are analysed in detail to determine the methods of attack, the purpose of the attack and the parties behind it
- Full Text:
Selected physiological and perceptual responses of batsmen during a simulated one day international century : impact on performance
- Authors: Pote, Lee
- Date: 2013 , 2013-04-02
- Subjects: Cricket -- Batting , Sports -- Physiological aspects , Sports -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5097 , http://hdl.handle.net/10962/d1001650
- Description: Background: Very few studies have examined the demands of prolonged batting on physical, psychophysical and performance responses. Objective: The purpose of this study was therefore to determine the physiological and perceptual responses of batsmen scoring a simulated One Day International century. Furthermore, the impact that these responses had on batting performance were also measured. Methods: Seventeen male cricketers currently playing for Rhodes University or the country districts side, performed a simulated bating innings (BATEX©), typical of scoring a One Day international century. The BATEX© protocol consisted of six, five over stages (21 minutes each), with each stage matched to a specific phase of play where batsmen were encouraged to bat with the mindset of that phase. During stages one, three and five players ran at a “self-selected cruise pace” whereas during stages two, four and six players were required to run at maximum speed. At set intervals, selected physiological, perceptual and performance measures were recorded. Results: Most physiological responses increased and decreased accordingly with the low and high intensity stages with the exception of respiratory exchange ratio and core temperature responses. Mean physiological responses however, showed a progressive rise over time. Central ratings of perceived exertion increased as a function of intensity and duration. Sprint times got slower as the protocol progressed, while accuracy (impact accuracy) improved significantly (p<0.05) after stage one and then stabilised for the remainder of the protocol. Conclusion: The simulated batting protocol significantly impacted the physiological and perceptual responses over time. This was due to both the intensity and the duration of the work-bout. Furthermore, the increased physiological load placed on the batsmen significantly impacted the physical performance of the batsmen. An increase in sprint times (players getting slower) towards the end of the protocol may indicate the presence of physical fatigue. This physical fatigue did not however seem to impact the batsmen cognitively as accuracy improved after the first stage and then remained constant over time.
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- Authors: Pote, Lee
- Date: 2013 , 2013-04-02
- Subjects: Cricket -- Batting , Sports -- Physiological aspects , Sports -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5097 , http://hdl.handle.net/10962/d1001650
- Description: Background: Very few studies have examined the demands of prolonged batting on physical, psychophysical and performance responses. Objective: The purpose of this study was therefore to determine the physiological and perceptual responses of batsmen scoring a simulated One Day International century. Furthermore, the impact that these responses had on batting performance were also measured. Methods: Seventeen male cricketers currently playing for Rhodes University or the country districts side, performed a simulated bating innings (BATEX©), typical of scoring a One Day international century. The BATEX© protocol consisted of six, five over stages (21 minutes each), with each stage matched to a specific phase of play where batsmen were encouraged to bat with the mindset of that phase. During stages one, three and five players ran at a “self-selected cruise pace” whereas during stages two, four and six players were required to run at maximum speed. At set intervals, selected physiological, perceptual and performance measures were recorded. Results: Most physiological responses increased and decreased accordingly with the low and high intensity stages with the exception of respiratory exchange ratio and core temperature responses. Mean physiological responses however, showed a progressive rise over time. Central ratings of perceived exertion increased as a function of intensity and duration. Sprint times got slower as the protocol progressed, while accuracy (impact accuracy) improved significantly (p<0.05) after stage one and then stabilised for the remainder of the protocol. Conclusion: The simulated batting protocol significantly impacted the physiological and perceptual responses over time. This was due to both the intensity and the duration of the work-bout. Furthermore, the increased physiological load placed on the batsmen significantly impacted the physical performance of the batsmen. An increase in sprint times (players getting slower) towards the end of the protocol may indicate the presence of physical fatigue. This physical fatigue did not however seem to impact the batsmen cognitively as accuracy improved after the first stage and then remained constant over time.
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Self, family and society in Nadine Gordimer's Burger's Daughter, Rachel Zadok's Gem Squash Tokoloshe, and Doris Lessings's The Grass is Singing
- Authors: O'Brien, Lauren Leigh
- Date: 2013 , 2013-09-08
- Subjects: Gordimer, Nadine. Burger's daughter -- Criticism and interpretation Zadok, Rachel. Gem Squash Tokoloshe -- Criticism and interpretation Lessing, Doris May, 1919-- The grass is singing -- Criticism and interpretation South African fiction (English) -- 20th century -- History and criticism South African fiction (English) -- 21st century -- History and criticism South Africa -- In literature South Africa -- Social life and customs Identification (Psychology) in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2271 , http://hdl.handle.net/10962/d1006771
- Description: This dissertation examines Nadine Gordimer’s Burger’s Daughter, Rachel Zadok’s Gem Squash Tokoloshe, and Doris Lessing’s The Grass is Singing. It focuses on the development of each of the protagonists’ identities in three realms: the individual, the familial and the societal. Additionally, it is concerned with the specific socio-political contexts in which the novels are set. It employs psychoanalytic and historical materialist frameworks in order to engage with the disparate areas of identity with which it is concerned. The introduction establishes the analytical perspective of the dissertation and explores the network of theoretical frames on which the dissertation relies. Additionally, it contextualises each of the novels, within their historical contexts, as well as in relation to the theory. The first chapter examines Nadine Gordimer’s Burger’s Daughter. It focuses on the protagonist’s assertion of an identity independent of her father’s role as a political activist, and her eventual acceptance of the universal difficulty in negotiating a life which is both private and political. The second chapter, on Rachel Zadok’s Gem Squash Tokoloshe, examines the relationship between the protagonist’s traumatic experiences as a child and her inability to assert an identity as an adult. The similarities between the protagonist’s attempts to address her traumas and thereby create herself anew and South Africa’s employment of the Truth and Reconciliation Commission as a means to acknowledge and engage with its traumatic history is of import. The third chapter which deals with Doris Lessing’s The Grass is Singing traces the life of its protagonist, whose identifications remain childish as a result of having witnessed her parents’ difficult relationship. Her understanding of the world is informed by a rigid, binary understanding, which is ultimately disrupted by her relationship with a black employee. She is incapable of readjusting her frame of reference, however, and ultimately goes mad. I conclude that, while my focus has been on personal, familial and social identifications, the standard terms in which identity is examined, namely, race, class, and gender, are present in each of the three tiers of identity with which I have been concerned.
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- Authors: O'Brien, Lauren Leigh
- Date: 2013 , 2013-09-08
- Subjects: Gordimer, Nadine. Burger's daughter -- Criticism and interpretation Zadok, Rachel. Gem Squash Tokoloshe -- Criticism and interpretation Lessing, Doris May, 1919-- The grass is singing -- Criticism and interpretation South African fiction (English) -- 20th century -- History and criticism South African fiction (English) -- 21st century -- History and criticism South Africa -- In literature South Africa -- Social life and customs Identification (Psychology) in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2271 , http://hdl.handle.net/10962/d1006771
- Description: This dissertation examines Nadine Gordimer’s Burger’s Daughter, Rachel Zadok’s Gem Squash Tokoloshe, and Doris Lessing’s The Grass is Singing. It focuses on the development of each of the protagonists’ identities in three realms: the individual, the familial and the societal. Additionally, it is concerned with the specific socio-political contexts in which the novels are set. It employs psychoanalytic and historical materialist frameworks in order to engage with the disparate areas of identity with which it is concerned. The introduction establishes the analytical perspective of the dissertation and explores the network of theoretical frames on which the dissertation relies. Additionally, it contextualises each of the novels, within their historical contexts, as well as in relation to the theory. The first chapter examines Nadine Gordimer’s Burger’s Daughter. It focuses on the protagonist’s assertion of an identity independent of her father’s role as a political activist, and her eventual acceptance of the universal difficulty in negotiating a life which is both private and political. The second chapter, on Rachel Zadok’s Gem Squash Tokoloshe, examines the relationship between the protagonist’s traumatic experiences as a child and her inability to assert an identity as an adult. The similarities between the protagonist’s attempts to address her traumas and thereby create herself anew and South Africa’s employment of the Truth and Reconciliation Commission as a means to acknowledge and engage with its traumatic history is of import. The third chapter which deals with Doris Lessing’s The Grass is Singing traces the life of its protagonist, whose identifications remain childish as a result of having witnessed her parents’ difficult relationship. Her understanding of the world is informed by a rigid, binary understanding, which is ultimately disrupted by her relationship with a black employee. She is incapable of readjusting her frame of reference, however, and ultimately goes mad. I conclude that, while my focus has been on personal, familial and social identifications, the standard terms in which identity is examined, namely, race, class, and gender, are present in each of the three tiers of identity with which I have been concerned.
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Sequence and structural investigation of the nonribosomal peptide synthetases of Bacillus atrophaeus UCMB 5137(63Z)
- Authors: Ryan, Candice Nancy
- Date: 2013 , 2013-04-19
- Subjects: Bacillus (Bacteria) , Peptides--Synthesis , Antibiotics , Drug resistance in microorganisms , Amino acids , Phytopathogenic microorganisms , Trees--Phylogeny , Ligases
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3891 , http://hdl.handle.net/10962/d1003057 , Bacillus (Bacteria) , Peptides--Synthesis , Antibiotics , Drug resistance in microorganisms , Amino acids , Phytopathogenic microorganisms , Trees--Phylogeny , Ligases
- Description: Due to increased plant resistance to the existing antibiotics produced, there is a need to develop alternatives. Nonribosomal peptides (NRPs) are important plant phytopathogens synthesized by nonribosomal peptide synthetases (NRPSs). In this study, a newly sequenced Bacillus strain Bacillus atrophaeus UCMB 5137 (63Z), found to have increased phytopathogenic activity, was investigated to gain insights to the possible reason behind this activity. NRPS modules were identified using a novel script that can act on unannotated, raw DNA sequences. The Structure Based Sequence Analysis Webserver was used to identify the amino acids incorporated into the final NRP, which were compared to the NRP database. Five NRPSs were found within the strain; fengycin/plipstatin, mycosubtilin, surfactin, bacillibactin and bacitracin. Some of the modules usually present for these NRPSs were not present in the test strain and only a few modules were found. A phylogenetic study was carried out and the topologies of the trees showed that genes were not transferred horizontally. It did, however, lead to the hypothesis that different NRPS genes are under different adaptive evolutionary pressures. Only slight conformational changes between L and D-conformation of amino acids were seen between the test and neighboring strains. All of the linker and terminal regions of synthetases were found to exhibit a large amount of conservation overall. Homology modeling was performed on the test strain on selected modules, TE and A-domains of fengycin and mycosubtilin synthetases. TE-domains between the different synthetases are different and specific for the NRP they facilitate release for. The NRPS from which the A-domain originates also influences substrate specificity as well as the module in which the A-domain occurs within the NRPS. Binding pockets of A-domains of differing substrate specificity were compared. Future work will include; refinement of the models and docking studies within the A-domain binding pocket. , Microsoft� Word 2010 , Adobe Acrobat 9.54 Paper Capture Plug-in
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- Authors: Ryan, Candice Nancy
- Date: 2013 , 2013-04-19
- Subjects: Bacillus (Bacteria) , Peptides--Synthesis , Antibiotics , Drug resistance in microorganisms , Amino acids , Phytopathogenic microorganisms , Trees--Phylogeny , Ligases
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3891 , http://hdl.handle.net/10962/d1003057 , Bacillus (Bacteria) , Peptides--Synthesis , Antibiotics , Drug resistance in microorganisms , Amino acids , Phytopathogenic microorganisms , Trees--Phylogeny , Ligases
- Description: Due to increased plant resistance to the existing antibiotics produced, there is a need to develop alternatives. Nonribosomal peptides (NRPs) are important plant phytopathogens synthesized by nonribosomal peptide synthetases (NRPSs). In this study, a newly sequenced Bacillus strain Bacillus atrophaeus UCMB 5137 (63Z), found to have increased phytopathogenic activity, was investigated to gain insights to the possible reason behind this activity. NRPS modules were identified using a novel script that can act on unannotated, raw DNA sequences. The Structure Based Sequence Analysis Webserver was used to identify the amino acids incorporated into the final NRP, which were compared to the NRP database. Five NRPSs were found within the strain; fengycin/plipstatin, mycosubtilin, surfactin, bacillibactin and bacitracin. Some of the modules usually present for these NRPSs were not present in the test strain and only a few modules were found. A phylogenetic study was carried out and the topologies of the trees showed that genes were not transferred horizontally. It did, however, lead to the hypothesis that different NRPS genes are under different adaptive evolutionary pressures. Only slight conformational changes between L and D-conformation of amino acids were seen between the test and neighboring strains. All of the linker and terminal regions of synthetases were found to exhibit a large amount of conservation overall. Homology modeling was performed on the test strain on selected modules, TE and A-domains of fengycin and mycosubtilin synthetases. TE-domains between the different synthetases are different and specific for the NRP they facilitate release for. The NRPS from which the A-domain originates also influences substrate specificity as well as the module in which the A-domain occurs within the NRPS. Binding pockets of A-domains of differing substrate specificity were compared. Future work will include; refinement of the models and docking studies within the A-domain binding pocket. , Microsoft� Word 2010 , Adobe Acrobat 9.54 Paper Capture Plug-in
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Social and cultural discourses that shape male youths' masculinity and conceptions of risk and vulnerability to HIV and AIDS in Rundu Urban Constituency, Kavango region, Namibia
- Authors: Shikukutu, Faustinus
- Date: 2013
- Subjects: AIDS (Disease) -- Social aspects -- Namibia -- Kavango AIDS (Disease) in adolescence -- Namibia -- Kavango HIV (Viruses) -- Social aspects -- Namibia -- Kavango HIV infections -- Risk factors -- Namibia -- Kavango Men -- Sexual behavior -- Namibia -- Kavango Gender identity -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1391 , http://hdl.handle.net/10962/d1001672
- Description: HIV and AIDS still challenges the best efforts of public health and medical establishments and continues to ravage communities around the world. While measures have been put in place to preclude it from further spread, recent studies in the field of HIV and AIDS prevention intimate that for more efficacious intervention to be realized, it is critical to understand and address the social and cultural practices which influence sexual behavior, particularly understanding how issues of masculinity plays a role in the perpetuation of these behavior. Relying on Bourdieu’s theory of social practice, this study explores the inherent enduring nature of habitus and its role in the production and maintenance of masculine and sexual identities that predispose young men to HIV and AIDS. The study was conducted in Rundu Urban Constituency in Kavango Region of Namibia to gain insight into male youth’s masculinity and conceptions of risk and vulnerability to HIV and AIDS. The study design was qualitative and interpretive in nature. Data collection strategies included focus group discussions and individual interviews. Twelve male youth aged 17-20 years in two secondary schools (six in each) were selected to participate in the study. Four focus group discussions and fourteen individual interviews were conducted. Institutional ethical clearance from both regional education office and the schools were obtained before undertaking the study. Participants also signed written consent forms before interviews started. The findings of this study revealed that young men from this community were under constant pressure to conform to dominant masculine norms and values. Key in the case of youth in the study was the need to procreate as a dominant marker of one’s masculine and sexual identity because it represented a primary source of a ‘real’ man’s social identity in this community. This masculine and sexual identity seemed in itself to be constructed along paternal lines and cultural beliefs, which youth preserved by not only complying, but also reproducing. The sexual activities they reported that would secure their position as `real` men were often those that put them at risk and made them vulnerable to the epidemic.
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- Authors: Shikukutu, Faustinus
- Date: 2013
- Subjects: AIDS (Disease) -- Social aspects -- Namibia -- Kavango AIDS (Disease) in adolescence -- Namibia -- Kavango HIV (Viruses) -- Social aspects -- Namibia -- Kavango HIV infections -- Risk factors -- Namibia -- Kavango Men -- Sexual behavior -- Namibia -- Kavango Gender identity -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1391 , http://hdl.handle.net/10962/d1001672
- Description: HIV and AIDS still challenges the best efforts of public health and medical establishments and continues to ravage communities around the world. While measures have been put in place to preclude it from further spread, recent studies in the field of HIV and AIDS prevention intimate that for more efficacious intervention to be realized, it is critical to understand and address the social and cultural practices which influence sexual behavior, particularly understanding how issues of masculinity plays a role in the perpetuation of these behavior. Relying on Bourdieu’s theory of social practice, this study explores the inherent enduring nature of habitus and its role in the production and maintenance of masculine and sexual identities that predispose young men to HIV and AIDS. The study was conducted in Rundu Urban Constituency in Kavango Region of Namibia to gain insight into male youth’s masculinity and conceptions of risk and vulnerability to HIV and AIDS. The study design was qualitative and interpretive in nature. Data collection strategies included focus group discussions and individual interviews. Twelve male youth aged 17-20 years in two secondary schools (six in each) were selected to participate in the study. Four focus group discussions and fourteen individual interviews were conducted. Institutional ethical clearance from both regional education office and the schools were obtained before undertaking the study. Participants also signed written consent forms before interviews started. The findings of this study revealed that young men from this community were under constant pressure to conform to dominant masculine norms and values. Key in the case of youth in the study was the need to procreate as a dominant marker of one’s masculine and sexual identity because it represented a primary source of a ‘real’ man’s social identity in this community. This masculine and sexual identity seemed in itself to be constructed along paternal lines and cultural beliefs, which youth preserved by not only complying, but also reproducing. The sexual activities they reported that would secure their position as `real` men were often those that put them at risk and made them vulnerable to the epidemic.
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