Ionic liquids as media for electro-organic synthesis
- Authors: Kruger, Elna
- Date: 2007
- Subjects: Ionic solutions , Inorganic compounds -- Synthesis , Electrochemistry
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10413 , http://hdl.handle.net/10948/538 , Ionic solutions , Inorganic compounds -- Synthesis , Electrochemistry
- Description: The IL’s used in this study were either synthesized or commercially available. Preparation of the IL’s involved 2 step processes: firstly the heating of distilled 1-methylimidazole with distilled 1-chlorobutane under reflux to obtain 1-butyl-3- methylimidazolium chloride; secondly, the metathesis reaction of sodium tetrafluoroborate with 1-butyl-3-methylimidazolium chloride to obtain 1-butyl-3- methylimidazolium tetrafluoroborate. The addition of sodium tetrafluoroborate, sodium hexafluorophosphate and lithium trifluoromethane sulfonamide with 1-butyl-3-methylimidazolium chloride produced good yields of 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide respectively. The IL’s are hygroscopic and must be stored under a nitrogen atmosphere. The IL’s were analyzed using 1H and 13C NMR analysis with CDCl3 as solvent. The physical and chemical properties of these IL’s were compared to commercial products. The physical and chemical properties compared well to reference values from the literature. The physical properties measured include the density, conductivity and electrochemical window. The electrochemical window is dependant primarily on the resistance of the cation to reduction and the resistance of the anion to oxidation. The electrochemical windows of the IL’s were very similar to the reference windows obtained from literature and it can be seen that some IL’s have a slightly lower window which can be due to water present. Water content in the IL’s was determined with the use of a Karl Fischer titrator, with Hydranal 5 Composite as titrant and HPLC grade methanol as the base. The concentration of halide in the IL’s was determined with a Perkin-Elmer ICP-MS.
- Full Text:
- Date Issued: 2007
- Authors: Kruger, Elna
- Date: 2007
- Subjects: Ionic solutions , Inorganic compounds -- Synthesis , Electrochemistry
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10413 , http://hdl.handle.net/10948/538 , Ionic solutions , Inorganic compounds -- Synthesis , Electrochemistry
- Description: The IL’s used in this study were either synthesized or commercially available. Preparation of the IL’s involved 2 step processes: firstly the heating of distilled 1-methylimidazole with distilled 1-chlorobutane under reflux to obtain 1-butyl-3- methylimidazolium chloride; secondly, the metathesis reaction of sodium tetrafluoroborate with 1-butyl-3-methylimidazolium chloride to obtain 1-butyl-3- methylimidazolium tetrafluoroborate. The addition of sodium tetrafluoroborate, sodium hexafluorophosphate and lithium trifluoromethane sulfonamide with 1-butyl-3-methylimidazolium chloride produced good yields of 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide respectively. The IL’s are hygroscopic and must be stored under a nitrogen atmosphere. The IL’s were analyzed using 1H and 13C NMR analysis with CDCl3 as solvent. The physical and chemical properties of these IL’s were compared to commercial products. The physical and chemical properties compared well to reference values from the literature. The physical properties measured include the density, conductivity and electrochemical window. The electrochemical window is dependant primarily on the resistance of the cation to reduction and the resistance of the anion to oxidation. The electrochemical windows of the IL’s were very similar to the reference windows obtained from literature and it can be seen that some IL’s have a slightly lower window which can be due to water present. Water content in the IL’s was determined with the use of a Karl Fischer titrator, with Hydranal 5 Composite as titrant and HPLC grade methanol as the base. The concentration of halide in the IL’s was determined with a Perkin-Elmer ICP-MS.
- Full Text:
- Date Issued: 2007
Isolation and characterization of genes encoding heat shock protein 70s (hsp 70s) from two species of the coelacanth, Latimeria chalumnae and Latimeria menadoensis
- Modisakeng, Keoagile William
- Authors: Modisakeng, Keoagile William
- Date: 2007
- Subjects: Coelacanth Coelacanth -- Genetics Heat shock proteins Molecular chaperones Proteins -- Analysis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3971 , http://hdl.handle.net/10962/d1004030
- Description: The extant coelacanths have a close resemblance to the coelacanth fossil records dating back to 230mya. Like their predecessors, the extant coelacanths inhabit rocky caves at a depth of 100-300m below sea level. In the Comoros, the water temperature at these depths is estimated to fluctuate between 14-20°C. High-level adaptation to these environment and lack of competition are thought to have led to the morphological uniformity and slow change throughout the history of the coelacanths. Under stress conditions, proteins unfold or misfold leading to the formation of aggregates. Molecular chaperones facilitate the correct folding of other proteins so that they can attain a stable tertiary structure. In addition, molecular chaperones aid the refolding of denatured proteins and the degradation of terminally misfolded protein after cellular stress. Heat shock proteins form one of the major classes of molecular chaperones. Here we show that, despite high-level adaptation to a unique habitat and slow change, the genome of the coelacanth encodes the major and highly conserved molecular chaperone, Hsp70. Latimeria menadoensis and Latimeria chalumnae contain intronless hsp70 genes encoding Hsp70 proteins archetypal of known Hsp70s. Based on the coelacanth codon usage, we have shown that bacterial protein expression systems, particularly Escherichia coli, may not be appropriate for the overproduction of coelacanth Hsp70s and coelacanth proteins in general. Also interesting, was the discovery that like the rat Hsc70, the L. menadoensis Hsp70 could not reverse thermal sensitivity in a temperate sensitive E. coli DnaK mutant strain, BB2362. We also report the successful isolation of a 1.2 kb region of L. menadoensis hsp70 upstream regulatory region. This region contain three putative heat shock elements, a TATA- box and two CAAT-boxes. This regulatory region resembled the Xenopus, mouse, and particularly tilapia hsp70 promoters, all of which have been shown to drive the expression of reporter genes in a heat dependent manner. Taken together, this data is the first to strongly suggest an inducible Hsp70-base cytoprotection mechanism in the coelacanth. It further provides basis to formulate testable predictions about the regulation, structure and function of Hsp70s in the living fossil, Latimeria.
- Full Text:
- Date Issued: 2007
- Authors: Modisakeng, Keoagile William
- Date: 2007
- Subjects: Coelacanth Coelacanth -- Genetics Heat shock proteins Molecular chaperones Proteins -- Analysis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3971 , http://hdl.handle.net/10962/d1004030
- Description: The extant coelacanths have a close resemblance to the coelacanth fossil records dating back to 230mya. Like their predecessors, the extant coelacanths inhabit rocky caves at a depth of 100-300m below sea level. In the Comoros, the water temperature at these depths is estimated to fluctuate between 14-20°C. High-level adaptation to these environment and lack of competition are thought to have led to the morphological uniformity and slow change throughout the history of the coelacanths. Under stress conditions, proteins unfold or misfold leading to the formation of aggregates. Molecular chaperones facilitate the correct folding of other proteins so that they can attain a stable tertiary structure. In addition, molecular chaperones aid the refolding of denatured proteins and the degradation of terminally misfolded protein after cellular stress. Heat shock proteins form one of the major classes of molecular chaperones. Here we show that, despite high-level adaptation to a unique habitat and slow change, the genome of the coelacanth encodes the major and highly conserved molecular chaperone, Hsp70. Latimeria menadoensis and Latimeria chalumnae contain intronless hsp70 genes encoding Hsp70 proteins archetypal of known Hsp70s. Based on the coelacanth codon usage, we have shown that bacterial protein expression systems, particularly Escherichia coli, may not be appropriate for the overproduction of coelacanth Hsp70s and coelacanth proteins in general. Also interesting, was the discovery that like the rat Hsc70, the L. menadoensis Hsp70 could not reverse thermal sensitivity in a temperate sensitive E. coli DnaK mutant strain, BB2362. We also report the successful isolation of a 1.2 kb region of L. menadoensis hsp70 upstream regulatory region. This region contain three putative heat shock elements, a TATA- box and two CAAT-boxes. This regulatory region resembled the Xenopus, mouse, and particularly tilapia hsp70 promoters, all of which have been shown to drive the expression of reporter genes in a heat dependent manner. Taken together, this data is the first to strongly suggest an inducible Hsp70-base cytoprotection mechanism in the coelacanth. It further provides basis to formulate testable predictions about the regulation, structure and function of Hsp70s in the living fossil, Latimeria.
- Full Text:
- Date Issued: 2007
Isolation of a Clostridium Beijerinckii sLM01 cellulosome and the effect of sulphide on anaerobic digestion
- Authors: Mayende, Lungisa
- Date: 2007
- Subjects: Cellulose , Clostridium , Cellulase , Sulfides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3973 , http://hdl.handle.net/10962/d1004032 , Cellulose , Clostridium , Cellulase , Sulfides
- Description: Cellulose is the most abundant and the most resistant and stable natural organic compound on earth. Enzyme hydrolysis is difficult because of its insolubility and heterogeneity. Some (anaerobic) microorganisms have overcome this by having a multienzyme system called the cellulosome. The aims of the study were to isolate a mesophilic Clostridium sp. from a biosulphidogenic bioreactor, to purify the cellulosome from this culture, to determine the cellulase and endoglucanase activities using Avicel and carboxymethylcellulose (CMC) as substrates and the dinitrosalicyclic (DNS) method. The organism was identified using 16S rDNA sequence analysis. The sequence obtained indicated that a strain of Clostridium beijerinckii was isolated. The cellulosome was purified from the putative C. beijerinckii sLM01 host culture using affinity chromatography purification and affinity digestion purification procedures. The cellulosomal and non-cellulosomal fractions of C. beijerinckii sLM01 were separated successfully, but the majority of the endoglucanase activity was lost during the Sepharose 4B chromatography step. These cellulosomal and non-cellulosomal fractions were characterised with regards to their pH and temperature optima and effector sensitivity. Increased additions of sulphide activated the cellulase activity of the cellulosomal and non-cellulosomal fractions up to 700 %, while increased additions of sulphate either increased the activity slightly or inhibited it dramatically, depending on the cellulosomal and non-cellulosomal fractions. Increased additions of cellobiose, glucose and acetate inhibited the cellulase and endoglucanase activities. pH optima of 5.0 and 7.5 were observed for cellulases and 5.0 for endoglucanases of the cellulosomal fraction. The noncellulosomal fraction exhibited a pH optimum of 7.5 for both cellulase and endoglucanase activities. Both fractions and enzymes exhibited a temperature optimum of 30 °C. The fundamental knowledge gained from the characterisation was applied to anaerobic digestion, where the effect of sulphide on the rate-limiting step was determined. Sulphide activated cellulase and endoglucanase activities and increased the % chemical oxygen demand (COD) removal rate. Levels of volatile fatty acids (VFAs) were higher in the bioreactor containing sulphide, substrate and C. beijerinckii. Sulphide therefore accelerated the rate-limiting step of anaerobic digestion.
- Full Text:
- Date Issued: 2007
- Authors: Mayende, Lungisa
- Date: 2007
- Subjects: Cellulose , Clostridium , Cellulase , Sulfides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3973 , http://hdl.handle.net/10962/d1004032 , Cellulose , Clostridium , Cellulase , Sulfides
- Description: Cellulose is the most abundant and the most resistant and stable natural organic compound on earth. Enzyme hydrolysis is difficult because of its insolubility and heterogeneity. Some (anaerobic) microorganisms have overcome this by having a multienzyme system called the cellulosome. The aims of the study were to isolate a mesophilic Clostridium sp. from a biosulphidogenic bioreactor, to purify the cellulosome from this culture, to determine the cellulase and endoglucanase activities using Avicel and carboxymethylcellulose (CMC) as substrates and the dinitrosalicyclic (DNS) method. The organism was identified using 16S rDNA sequence analysis. The sequence obtained indicated that a strain of Clostridium beijerinckii was isolated. The cellulosome was purified from the putative C. beijerinckii sLM01 host culture using affinity chromatography purification and affinity digestion purification procedures. The cellulosomal and non-cellulosomal fractions of C. beijerinckii sLM01 were separated successfully, but the majority of the endoglucanase activity was lost during the Sepharose 4B chromatography step. These cellulosomal and non-cellulosomal fractions were characterised with regards to their pH and temperature optima and effector sensitivity. Increased additions of sulphide activated the cellulase activity of the cellulosomal and non-cellulosomal fractions up to 700 %, while increased additions of sulphate either increased the activity slightly or inhibited it dramatically, depending on the cellulosomal and non-cellulosomal fractions. Increased additions of cellobiose, glucose and acetate inhibited the cellulase and endoglucanase activities. pH optima of 5.0 and 7.5 were observed for cellulases and 5.0 for endoglucanases of the cellulosomal fraction. The noncellulosomal fraction exhibited a pH optimum of 7.5 for both cellulase and endoglucanase activities. Both fractions and enzymes exhibited a temperature optimum of 30 °C. The fundamental knowledge gained from the characterisation was applied to anaerobic digestion, where the effect of sulphide on the rate-limiting step was determined. Sulphide activated cellulase and endoglucanase activities and increased the % chemical oxygen demand (COD) removal rate. Levels of volatile fatty acids (VFAs) were higher in the bioreactor containing sulphide, substrate and C. beijerinckii. Sulphide therefore accelerated the rate-limiting step of anaerobic digestion.
- Full Text:
- Date Issued: 2007
Isolation of bioactive metabolites with activity against HIV-1 target proteins from extracts of Sutherlandia frutescens and Lobostemon trigonus
- Authors: Dambuza, Ntokozo Shirley
- Date: 2007
- Subjects: Medicinal plants -- Africa, Southern , HIV infections -- Alternative treatment -- Africa, Southern , Plant bioactive compounds
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10335 , http://hdl.handle.net/10948/492 , http://hdl.handle.net/10948/d1012003 , Medicinal plants -- Africa, Southern , HIV infections -- Alternative treatment -- Africa, Southern , Plant bioactive compounds
- Description: Acquired Immunodeficiency Syndrome (AIDS) is a human disease caused by the human immunodeficiency virus type 1 (HIV-1) and it is one of the biggest social, economic and health challenges in the world. The Joint United Nations Programme on HIV/AIDS (UNAIDS) and World Health Organization (WHO) estimated that between 33.4 to 46.0 million people around the world were living with HIV/AIDS in December 2005 and the highest estimates are in the Sub-Saharan Africa (around 25 million). In more developed countries a combined antiretroviral therapy called highly active antiretroviral therapy (HAART) is used, which results in reduced progression to AIDS in most patients. Despite the beneficial effects of HAART, significant side effects are experienced by treated patients. In addition, most infected people live in countries where the treatment is very expensive or, in many cases, not available at all. These people therefore rely on medicinal plants for health care. In this study, aqueous extracts from Sutherlandia frutescens and Lobostemon trigonus were screened for potential anti-HIV activities in a series of in vitro enzymatic assays, including reverse transcriptase, HIV-1 protease and glycohydrolases. Two extracts of Sutherlandia leaves (SFL-1 and SFL-2) were prepared that inhibited HIV reverse transcriptase and a Lobostemon leaf extract (LTL) was shown to also inhibit this enzyme. All extracts were assayed at 1.25mg/ml. Tannin content was determined for all active extracts using a tannic acid assay. SFL-1 and SFL-2 were found to contain about 6 percent and 7 percent tannins, respectively, and LTL contained 31% tannins by weight. Tannins were removed using polyamide columns and three fractions were collected for each. The extracts were also fractionated with Sephadex G-25, Amberlite IR 120 and Dowex 1-X8 as size exclusion, cation exchange and anion exchange, respectively. Extracts were also fractionated by preparative thin layer chromatography where two compounds were separated from S. frutescens extract with high activity against reverse transcriptase while showing insignificant inhibition towards other enzymes tested. SFL-BFW-10 and SFL-WEF-7 inhibited reverse transcriptase by almost 100 percent and the IC50 values calculated for these compounds were 0.34 and 0.23mg/ml, respectively. Cytotoxicity of these compounds was evaluated on Chang liver cells and peripheral blood mononuclear cells (PBMCs). None of these compounds showed any significant inhibition of cell proliferation. The purity of these compounds could not be confirmed because there was insufficient material to use in the techniques required to show purity and identification. Therefore, TLC was used to determine the nature of these compounds. SFL-BFW-10 was identified as an organic acid and SFL-WEF-7 was identified as flavonoid.
- Full Text:
- Date Issued: 2007
- Authors: Dambuza, Ntokozo Shirley
- Date: 2007
- Subjects: Medicinal plants -- Africa, Southern , HIV infections -- Alternative treatment -- Africa, Southern , Plant bioactive compounds
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10335 , http://hdl.handle.net/10948/492 , http://hdl.handle.net/10948/d1012003 , Medicinal plants -- Africa, Southern , HIV infections -- Alternative treatment -- Africa, Southern , Plant bioactive compounds
- Description: Acquired Immunodeficiency Syndrome (AIDS) is a human disease caused by the human immunodeficiency virus type 1 (HIV-1) and it is one of the biggest social, economic and health challenges in the world. The Joint United Nations Programme on HIV/AIDS (UNAIDS) and World Health Organization (WHO) estimated that between 33.4 to 46.0 million people around the world were living with HIV/AIDS in December 2005 and the highest estimates are in the Sub-Saharan Africa (around 25 million). In more developed countries a combined antiretroviral therapy called highly active antiretroviral therapy (HAART) is used, which results in reduced progression to AIDS in most patients. Despite the beneficial effects of HAART, significant side effects are experienced by treated patients. In addition, most infected people live in countries where the treatment is very expensive or, in many cases, not available at all. These people therefore rely on medicinal plants for health care. In this study, aqueous extracts from Sutherlandia frutescens and Lobostemon trigonus were screened for potential anti-HIV activities in a series of in vitro enzymatic assays, including reverse transcriptase, HIV-1 protease and glycohydrolases. Two extracts of Sutherlandia leaves (SFL-1 and SFL-2) were prepared that inhibited HIV reverse transcriptase and a Lobostemon leaf extract (LTL) was shown to also inhibit this enzyme. All extracts were assayed at 1.25mg/ml. Tannin content was determined for all active extracts using a tannic acid assay. SFL-1 and SFL-2 were found to contain about 6 percent and 7 percent tannins, respectively, and LTL contained 31% tannins by weight. Tannins were removed using polyamide columns and three fractions were collected for each. The extracts were also fractionated with Sephadex G-25, Amberlite IR 120 and Dowex 1-X8 as size exclusion, cation exchange and anion exchange, respectively. Extracts were also fractionated by preparative thin layer chromatography where two compounds were separated from S. frutescens extract with high activity against reverse transcriptase while showing insignificant inhibition towards other enzymes tested. SFL-BFW-10 and SFL-WEF-7 inhibited reverse transcriptase by almost 100 percent and the IC50 values calculated for these compounds were 0.34 and 0.23mg/ml, respectively. Cytotoxicity of these compounds was evaluated on Chang liver cells and peripheral blood mononuclear cells (PBMCs). None of these compounds showed any significant inhibition of cell proliferation. The purity of these compounds could not be confirmed because there was insufficient material to use in the techniques required to show purity and identification. Therefore, TLC was used to determine the nature of these compounds. SFL-BFW-10 was identified as an organic acid and SFL-WEF-7 was identified as flavonoid.
- Full Text:
- Date Issued: 2007
Isolation of microsatellite markers for the endangered Knysna seahorse Hippocampus capensis and their use in the detection of a genetic bottleneck
- Galbusera, Peter H A, Gillemot, Sarah, Jouk, Phillippe, Teske, Peter R, Hellemans, Bart, Volckaert, Filip A M J
- Authors: Galbusera, Peter H A , Gillemot, Sarah , Jouk, Phillippe , Teske, Peter R , Hellemans, Bart , Volckaert, Filip A M J
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445678 , vital:74413 , https://doi.org/10.1111/j.1471-8286.2007.01688.x
- Description: We report the isolation and characterization of 15 (12 di‐, 1 tri‐ and 2 tetranucleotide) microsatellite markers from Hippocampus capensis, the Knysna seahorse. This marker set allows the detection of a genetic bottleneck as shown in a captive population. Furthermore, we test their genotyping potential in eight other seahorse taxa.
- Full Text:
- Date Issued: 2007
- Authors: Galbusera, Peter H A , Gillemot, Sarah , Jouk, Phillippe , Teske, Peter R , Hellemans, Bart , Volckaert, Filip A M J
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445678 , vital:74413 , https://doi.org/10.1111/j.1471-8286.2007.01688.x
- Description: We report the isolation and characterization of 15 (12 di‐, 1 tri‐ and 2 tetranucleotide) microsatellite markers from Hippocampus capensis, the Knysna seahorse. This marker set allows the detection of a genetic bottleneck as shown in a captive population. Furthermore, we test their genotyping potential in eight other seahorse taxa.
- Full Text:
- Date Issued: 2007
Isolation, propagation and rapid molecular detection of the Kalahari truffle, a mycorrhizal fungus occurring in South Africa
- Authors: Adeleke, Rasheed Adegbola
- Date: 2007 , 2013-04-03
- Subjects: Truffles -- Kalahari Desert , Fungi -- Identification , Mycorrhizal fungi -- South Africa , Edible fungi -- South Africa , Mushroom culture -- South Africa , Fungi -- Cultures and culture media -- South Africa , Truffles -- South Africa , Truffles -- Lifecycles , Mycorrhizal fungi -- Lifecycles
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3889 , http://hdl.handle.net/10962/d1002951 , Truffles -- Kalahari Desert , Fungi -- Identification , Mycorrhizal fungi -- South Africa , Edible fungi -- South Africa , Mushroom culture -- South Africa , Fungi -- Cultures and culture media -- South Africa , Truffles -- South Africa , Truffles -- Lifecycles , Mycorrhizal fungi -- Lifecycles
- Description: Terfezia pfeilii is an edible mycorrhizal fungus that thrives in the Kalahari Desert of southern Africa. It is best known by desert dwellers for its flavour and as a source of nutrition. Although the genus Terfezia is generally regarded as being an ectomycorrhizal mycobiont, the exact mycorrhizal type formed by T. pfeilli and its' associated host plants remains uncertain. Discovery of the host plants for T. pfeilii would first be required in order to further investigate the life cycle and cultivation of this truffle. This study focussed on the isolation of mycelia from the ascocarp, optimising the growth conditions of the mycelial cultures, rapid molecular identification of T. pfeilii, investigation of potential helper bacteria and mycorrhizal synthesis experiments. T. pfeilii ascocarps were harvested from the Spitskop Nature Reserve in Upington, South Africa. Ascocarps were successfully identified using both morphological and molecular methods. Despite the delayed growth mostly caused by contaminating microorganisms, the isolation of T. pfeilii mycelia culture was successful. Molecular techniques were used to confirm the identity of the pure culture. Further studies were conducted on ways to improve the growth conditions of the mycelial culture on Fontana medium. An optimum temperature of 32°C, the addition of Bovine Serum Albumin as a nitrogen source and a pH of 7.5 significantly improved the growth of T. pfeilii in vitro. A rapid PeR-based molecular method was developed to speed up the identification of T. pfeilii. Specific primers that can exclusively amplify the ITS region of T. pfeilii were designed and used to identify both the ascocarps and the mycelial culture. The specificity of these primers was confirmed by their inability to amplify DNA from the isolates of contamining fungi obtained during the isolation process. Molecular comparison was made to confirm the reclassification of South African samples of T. pfeilii as Kalaharituber pfeilii as proposed by Ferdman et al.,(2005). However, in this study, the name T. pfeilii has been retained. A total of 17 bacterial isolates were obtained from the fruiting bodies of T. pfeaii and these were tested for stimulation of mycelial growth in vitro, indole production and phosphate solubilising capabilities. Bacterial isolates that showed potential to be Mycorrhization Helper Bacteria (MHB) were identified as Paenibacillus sp., Bacillus sp. and Rhizobium tropici. Selected plant seedlings were inoculated with T. pfeilii cultures or ascocarp slurry in order to re-establish the mycorrhizal association. After 8 months, light microscopy observations revealed an endomycorrhizal type association between Cynodon dactylon and T. pfeilii. This was confirmed with molecular analysis using specific T. pfeilii ITS primers. After 15 months, molecular methods confirmed Acacia erioloba as another host plant. These results have provided essential information paving the way for further investigation into the life cycle and biology of the Kalahari truffle. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 2007
- Authors: Adeleke, Rasheed Adegbola
- Date: 2007 , 2013-04-03
- Subjects: Truffles -- Kalahari Desert , Fungi -- Identification , Mycorrhizal fungi -- South Africa , Edible fungi -- South Africa , Mushroom culture -- South Africa , Fungi -- Cultures and culture media -- South Africa , Truffles -- South Africa , Truffles -- Lifecycles , Mycorrhizal fungi -- Lifecycles
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3889 , http://hdl.handle.net/10962/d1002951 , Truffles -- Kalahari Desert , Fungi -- Identification , Mycorrhizal fungi -- South Africa , Edible fungi -- South Africa , Mushroom culture -- South Africa , Fungi -- Cultures and culture media -- South Africa , Truffles -- South Africa , Truffles -- Lifecycles , Mycorrhizal fungi -- Lifecycles
- Description: Terfezia pfeilii is an edible mycorrhizal fungus that thrives in the Kalahari Desert of southern Africa. It is best known by desert dwellers for its flavour and as a source of nutrition. Although the genus Terfezia is generally regarded as being an ectomycorrhizal mycobiont, the exact mycorrhizal type formed by T. pfeilli and its' associated host plants remains uncertain. Discovery of the host plants for T. pfeilii would first be required in order to further investigate the life cycle and cultivation of this truffle. This study focussed on the isolation of mycelia from the ascocarp, optimising the growth conditions of the mycelial cultures, rapid molecular identification of T. pfeilii, investigation of potential helper bacteria and mycorrhizal synthesis experiments. T. pfeilii ascocarps were harvested from the Spitskop Nature Reserve in Upington, South Africa. Ascocarps were successfully identified using both morphological and molecular methods. Despite the delayed growth mostly caused by contaminating microorganisms, the isolation of T. pfeilii mycelia culture was successful. Molecular techniques were used to confirm the identity of the pure culture. Further studies were conducted on ways to improve the growth conditions of the mycelial culture on Fontana medium. An optimum temperature of 32°C, the addition of Bovine Serum Albumin as a nitrogen source and a pH of 7.5 significantly improved the growth of T. pfeilii in vitro. A rapid PeR-based molecular method was developed to speed up the identification of T. pfeilii. Specific primers that can exclusively amplify the ITS region of T. pfeilii were designed and used to identify both the ascocarps and the mycelial culture. The specificity of these primers was confirmed by their inability to amplify DNA from the isolates of contamining fungi obtained during the isolation process. Molecular comparison was made to confirm the reclassification of South African samples of T. pfeilii as Kalaharituber pfeilii as proposed by Ferdman et al.,(2005). However, in this study, the name T. pfeilii has been retained. A total of 17 bacterial isolates were obtained from the fruiting bodies of T. pfeaii and these were tested for stimulation of mycelial growth in vitro, indole production and phosphate solubilising capabilities. Bacterial isolates that showed potential to be Mycorrhization Helper Bacteria (MHB) were identified as Paenibacillus sp., Bacillus sp. and Rhizobium tropici. Selected plant seedlings were inoculated with T. pfeilii cultures or ascocarp slurry in order to re-establish the mycorrhizal association. After 8 months, light microscopy observations revealed an endomycorrhizal type association between Cynodon dactylon and T. pfeilii. This was confirmed with molecular analysis using specific T. pfeilii ITS primers. After 15 months, molecular methods confirmed Acacia erioloba as another host plant. These results have provided essential information paving the way for further investigation into the life cycle and biology of the Kalahari truffle. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 2007
JM Coetzee and the ethics of reading:
- Authors: Marais, Mike
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144253 , vital:38325 , https://www.jstor.org/stable/pdf/26286886.pdf
- Description: One of Derek Attridge's principal concerns in J. M. Coetzee and the Ethics of Reading is the relationship that is established with alterity in the writing and reading of literary works. As is evident from the fact that some of the chapters in the book date back more than a decade, this is an abiding concern. Indeed, The Singularity of Literature, which also appeared in 2004, theorizes this relationship at great length. In it, Attridge describes the literary text as the emanation of an act of creation, that is, that mysterious experience in which the writer, who is located in culture's familiar modes of understanding, encounters something strange (in that it does not yet exist within the horizon that culture provides for thinking and feeling) and is required to resist the mind's tendency to reduce novelty by understanding it in terms of the familiar.
- Full Text:
- Date Issued: 2007
- Authors: Marais, Mike
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144253 , vital:38325 , https://www.jstor.org/stable/pdf/26286886.pdf
- Description: One of Derek Attridge's principal concerns in J. M. Coetzee and the Ethics of Reading is the relationship that is established with alterity in the writing and reading of literary works. As is evident from the fact that some of the chapters in the book date back more than a decade, this is an abiding concern. Indeed, The Singularity of Literature, which also appeared in 2004, theorizes this relationship at great length. In it, Attridge describes the literary text as the emanation of an act of creation, that is, that mysterious experience in which the writer, who is located in culture's familiar modes of understanding, encounters something strange (in that it does not yet exist within the horizon that culture provides for thinking and feeling) and is required to resist the mind's tendency to reduce novelty by understanding it in terms of the familiar.
- Full Text:
- Date Issued: 2007
John Michael Berning (14.12.1941- 17.12.2006) : obituary
- Authors: Lewis, Colin A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6184 , http://hdl.handle.net/10962/d1012381
- Description: [From Introduction] Mike Berning was born in 1941. He attended the King Edward VII School in Johannesburg before going up to Rhodes University in 1960, where he read Honours in History, graduating in 1963. Having decided on a career in librarianship, Mike proceeded from Rhodes to the University of Cape Town in 1964, initially to read for a Certificate in that subject. In 1968 he was awarded his Diploma in Librarianship from UCT. In the first part of 1965 Mike was employed in the South African Library in Cape Town, but in September of that year he was appointed Librarian of the Cory Library at Rhodes University. From 1978 until 1986 he acted as Deputy to the University Librarian until, in 1988, the post of Deputy University Librarian was created, to which he was appointed. Mike retired in 1999. , Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
- Full Text:
- Date Issued: 2007
- Authors: Lewis, Colin A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6184 , http://hdl.handle.net/10962/d1012381
- Description: [From Introduction] Mike Berning was born in 1941. He attended the King Edward VII School in Johannesburg before going up to Rhodes University in 1960, where he read Honours in History, graduating in 1963. Having decided on a career in librarianship, Mike proceeded from Rhodes to the University of Cape Town in 1964, initially to read for a Certificate in that subject. In 1968 he was awarded his Diploma in Librarianship from UCT. In the first part of 1965 Mike was employed in the South African Library in Cape Town, but in September of that year he was appointed Librarian of the Cory Library at Rhodes University. From 1978 until 1986 he acted as Deputy to the University Librarian until, in 1988, the post of Deputy University Librarian was created, to which he was appointed. Mike retired in 1999. , Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
- Full Text:
- Date Issued: 2007
Karen Horney : a psychobiographical study
- Authors: Green, Sarah-Jane
- Date: 2007
- Subjects: Horney, Karen, 1885-1952 Women psychologists Levinson, Daniel J., d.1994 Levinson, Daniel J., d.1994 -- The seasons of a woman's life
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3186 , http://hdl.handle.net/10962/d1008374
- Description: This psychobiography on the life of Karen Horney is an exploratory-descriptive study that aims to explore and describe Horney's life structure development according to Daniel Levinson's (1996) theory of adult development. The method of research uses a qualitative single-case research design that studies her life over her entire lifespan and highlights the individual characteristics of Horney in a holistic manner within her socio-historical context. A purposive sampling procedure was used to select Karen Horney as the subject of the research and only published data was analyzed in the research. Multiple sources of data are used to obtain the information in this research, including an autobiography and three biographies written by three different authors. This data is organized according to the temporal sequence of her lifespan and the developmental periods and time frame of Levinson's theory. Horney's life is described and explored to highlight those areas of her life that conform to the developmental theory and those aspects of her life that are not included in the theoretical constructs of Levinson 's theory. By exploring the significant relationships that Horney developed throughout her life with family, friends, work colleagues, community and religious affiliations, and the important issues in her development, this study verifies Levinson's theory by corroborating his conceptualisation of adult development as a process of sequential stages divided into four main eras of development, linked by three periods of transition. A shortcoming of Levinson's theory relates to his omission of self-esteem issues and religious concerns as relevant factors experienced during the era of pre-adulthood and spiritual concerns during the era of late adulthood.
- Full Text:
- Date Issued: 2007
- Authors: Green, Sarah-Jane
- Date: 2007
- Subjects: Horney, Karen, 1885-1952 Women psychologists Levinson, Daniel J., d.1994 Levinson, Daniel J., d.1994 -- The seasons of a woman's life
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3186 , http://hdl.handle.net/10962/d1008374
- Description: This psychobiography on the life of Karen Horney is an exploratory-descriptive study that aims to explore and describe Horney's life structure development according to Daniel Levinson's (1996) theory of adult development. The method of research uses a qualitative single-case research design that studies her life over her entire lifespan and highlights the individual characteristics of Horney in a holistic manner within her socio-historical context. A purposive sampling procedure was used to select Karen Horney as the subject of the research and only published data was analyzed in the research. Multiple sources of data are used to obtain the information in this research, including an autobiography and three biographies written by three different authors. This data is organized according to the temporal sequence of her lifespan and the developmental periods and time frame of Levinson's theory. Horney's life is described and explored to highlight those areas of her life that conform to the developmental theory and those aspects of her life that are not included in the theoretical constructs of Levinson 's theory. By exploring the significant relationships that Horney developed throughout her life with family, friends, work colleagues, community and religious affiliations, and the important issues in her development, this study verifies Levinson's theory by corroborating his conceptualisation of adult development as a process of sequential stages divided into four main eras of development, linked by three periods of transition. A shortcoming of Levinson's theory relates to his omission of self-esteem issues and religious concerns as relevant factors experienced during the era of pre-adulthood and spiritual concerns during the era of late adulthood.
- Full Text:
- Date Issued: 2007
Karyology of three evolutionarily hexaploid southern African species of yellowfish, Labeobarbus Rüppel, 1836 (Cyprinidae)
- Naran, Daksha, Skelton, Paul H, Villet, Martin H
- Authors: Naran, Daksha , Skelton, Paul H , Villet, Martin H
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6855 , http://hdl.handle.net/10962/d1011138 , http://dx.doi.org/10.3377/1562-7020(2007)42[254:KOTEHS]2.0.CO;2
- Description: The karyotypes of three species of yellowfish, namely Labeobarbus marequensis (A. Smith, 1841), L. capensis (A. Smith, 1841) and L. polylepis (Boulenger, 1907), were examined by Giemsa staining using an approach improved for the description of high chromosome numbers. In each case, 2n = 150; no heteromorphic chromosomes were detected; chromosomes in all morphological categories ranged smoothly from large to small, with no distinctly large submetacentric pairs; and metacentric chromosomes showed little variation in size. Labeobarbus marequensis had 26 metacentric (m), 44 submetacentric (sm), 42 subtelocentric (st) and 38 acrocentric (a) chromosomes and a fundamental number (FN) of 262; L. capensis had 16 m, 58 sm, 42 st and 34 a chromosomes and FN = 266; and L. polylepis had 18 m, 60 sm, 42 st and 30 a chromosomes and FN = 270. These results, combined with published literature, imply that Labeobarbus Rüppel, 1836 is an evolutionarily hexaploid African lineage and support its removal from synonymy with the evolutionarily tetraploid Asian genus Tor Gray, 1834. A review of fundamental numbers for conspecific Labeobarbus species examined in different studies implicated karyological technique as a confounding factor in assessing details of karyotypes, leading to recommendations for future karyological studies of barbine fishes. Potential synapomorphies are pointed out in karyological characters of species within Labeobarbus.
- Full Text:
- Date Issued: 2007
- Authors: Naran, Daksha , Skelton, Paul H , Villet, Martin H
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6855 , http://hdl.handle.net/10962/d1011138 , http://dx.doi.org/10.3377/1562-7020(2007)42[254:KOTEHS]2.0.CO;2
- Description: The karyotypes of three species of yellowfish, namely Labeobarbus marequensis (A. Smith, 1841), L. capensis (A. Smith, 1841) and L. polylepis (Boulenger, 1907), were examined by Giemsa staining using an approach improved for the description of high chromosome numbers. In each case, 2n = 150; no heteromorphic chromosomes were detected; chromosomes in all morphological categories ranged smoothly from large to small, with no distinctly large submetacentric pairs; and metacentric chromosomes showed little variation in size. Labeobarbus marequensis had 26 metacentric (m), 44 submetacentric (sm), 42 subtelocentric (st) and 38 acrocentric (a) chromosomes and a fundamental number (FN) of 262; L. capensis had 16 m, 58 sm, 42 st and 34 a chromosomes and FN = 266; and L. polylepis had 18 m, 60 sm, 42 st and 30 a chromosomes and FN = 270. These results, combined with published literature, imply that Labeobarbus Rüppel, 1836 is an evolutionarily hexaploid African lineage and support its removal from synonymy with the evolutionarily tetraploid Asian genus Tor Gray, 1834. A review of fundamental numbers for conspecific Labeobarbus species examined in different studies implicated karyological technique as a confounding factor in assessing details of karyotypes, leading to recommendations for future karyological studies of barbine fishes. Potential synapomorphies are pointed out in karyological characters of species within Labeobarbus.
- Full Text:
- Date Issued: 2007
Killing for the camera?: an investigation into the relationship between serial killers and the media
- Authors: Olivier, Erin Monique
- Date: 2007
- Subjects: Serial murderers -- Press coverage , Serial murders in mass media , Violence in mass media
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8411 , http://hdl.handle.net/10948/587 , http://hdl.handle.net/10948/d1011672 , Serial murderers -- Press coverage , Serial murders in mass media , Violence in mass media
- Description: This study focuses on the role of media portrayal and coverage in serial killing. The first objective of the study is to develop a conceptual structure that aids in the understanding of the cyclical relationship between media, serial killer, and audience. The media acts as a catalyst in this relationship, providing the stage on which serial killer and audience form a fatal relationship in which celebrity status forms the ultimate motivation. Media sensationalism of serial killing and the extreme glamorization in fictional representations has obviously negative consequences. In developing such a structure I hope to demonstrate that there is an alternative to the sensationalizing and glamorizing of serial killers in the media. This alternative will take the form education and a more documentary-style approach to films about serial murder. The study focuses mainly on developing a theoretical framework that emphasizes each of the three elements of the cyclical relationship mentioned above separately. The second chapter is devoted to the media and its role. The third chapter focuses on serial killers and the motivations involved. The fourth chapter deals with the audience attracted to serial killing as a source of identification. A number of thinkers’ work is used in coming to grips with this relationship, including both American and South African authors. The fifth and final chapter takes into consideration the moment of application by addressing the South African situation. I conclude by discussing the repercussions of media glamorization and possible documentary-style alternatives.
- Full Text:
- Date Issued: 2007
Killing for the camera?: an investigation into the relationship between serial killers and the media
- Authors: Olivier, Erin Monique
- Date: 2007
- Subjects: Serial murderers -- Press coverage , Serial murders in mass media , Violence in mass media
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8411 , http://hdl.handle.net/10948/587 , http://hdl.handle.net/10948/d1011672 , Serial murderers -- Press coverage , Serial murders in mass media , Violence in mass media
- Description: This study focuses on the role of media portrayal and coverage in serial killing. The first objective of the study is to develop a conceptual structure that aids in the understanding of the cyclical relationship between media, serial killer, and audience. The media acts as a catalyst in this relationship, providing the stage on which serial killer and audience form a fatal relationship in which celebrity status forms the ultimate motivation. Media sensationalism of serial killing and the extreme glamorization in fictional representations has obviously negative consequences. In developing such a structure I hope to demonstrate that there is an alternative to the sensationalizing and glamorizing of serial killers in the media. This alternative will take the form education and a more documentary-style approach to films about serial murder. The study focuses mainly on developing a theoretical framework that emphasizes each of the three elements of the cyclical relationship mentioned above separately. The second chapter is devoted to the media and its role. The third chapter focuses on serial killers and the motivations involved. The fourth chapter deals with the audience attracted to serial killing as a source of identification. A number of thinkers’ work is used in coming to grips with this relationship, including both American and South African authors. The fifth and final chapter takes into consideration the moment of application by addressing the South African situation. I conclude by discussing the repercussions of media glamorization and possible documentary-style alternatives.
- Full Text:
- Date Issued: 2007
Laboratory investigation of a load carriage task observed in forestry
- Authors: Furney, Sheena Elizabeth
- Date: 2007
- Subjects: Work -- Physiological aspects , Foresters -- Workload , Human engineering , Lifting and carrying
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5145 , http://hdl.handle.net/10962/d1008188 , Work -- Physiological aspects , Foresters -- Workload , Human engineering , Lifting and carrying
- Description: The objective of the present study was to investigate and compare the human responses to two load carriage tasks performed with three different load masses and on three different gradients. The task of carrying hydrogel in one hand was observed in a silviculture industry and crude physiological and perceptual responses were measured. This task was simulated in a laboratory setting together with a suggested intervention of backpack carriage. Eighteen conditions were established which consisted of the two modes of carriage and a combination of three load masses (9kg, 12kg and 15kg) and three gradients (5%, 10% and 15%). Twenty eight Rhodes University female students comprised the sample and the experimental procedures were conducted on a Quinton treadmill. Each participant was required to complete nine of the eighteen conditions which were each four minutes in duration. Postural changes were assessed using lateral and posterior digital images taken at the second and fourth minute and compression and shearing forces were estimated with the ErgolmagerTM Physiological responses (heart rate, ventilation and metabolic responses) were measured continuously with the Quark b² and perceptual responses ('central' and 'local' RPE) were measured every minute during the experimentation and body discomfort was rated at the completion of each condition. Overall responses revealed that hand carriage (146 bt.min⁻¹ , 25.09 mIO₂. kg-l.min⁻¹) was generally found to be more physiologically stressful than backpack carriage (130 bt.min⁻¹, 22.15 mIO₂.kg⁻¹ .min⁻¹) independent of load mass and gradient. Physiological responses were higher (113 bt.min-1 to 174 bt.min⁻¹ ) in responses to increasing gradient as opposed to increasing load mass (104 bt.min-1 to 153 bt.min⁻¹ ) for both backpack and hand carriage. Categorisation using the guidelines of Sanders and McCormick (1993) allowed for classification of conditions, with respect to physiological responses, into 'moderate', 'heavy' and 'very heavy' stress. For almost all of the physiological responses the majority of conditions which were classified as 'moderate' were backpack carriage conditions and the conditions classified as 'very heavy' were mostly hand carriage conditions. In terms of postural responses hand carriage resulted in more strain and greater compression and shearing forces on the spine. In terms of the compression forces increasing gradient had a greater affect on backpack carriage (681 N to 935 N) compared to hand carriage (570N to 793N). In contrast, increasing load mass had a larger affect on hand carriage postures and compression forces (751 N to 935N) in comparison to backpack carriage (723N to 780N). Shearing forces were found to be worse in hand carriage conditions overall. Although participants generally underrated perceived exertion in relation to cardiorespiratory responses, these perceptions revealed that backpack carriage, with a mean 'central' RPE of 12 compared to 11 for hand carriage, was somewhat preferred to hand carriage and that increasing gradient was perceived to be marginally more straining than increasing load mass.
- Full Text:
- Date Issued: 2007
- Authors: Furney, Sheena Elizabeth
- Date: 2007
- Subjects: Work -- Physiological aspects , Foresters -- Workload , Human engineering , Lifting and carrying
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5145 , http://hdl.handle.net/10962/d1008188 , Work -- Physiological aspects , Foresters -- Workload , Human engineering , Lifting and carrying
- Description: The objective of the present study was to investigate and compare the human responses to two load carriage tasks performed with three different load masses and on three different gradients. The task of carrying hydrogel in one hand was observed in a silviculture industry and crude physiological and perceptual responses were measured. This task was simulated in a laboratory setting together with a suggested intervention of backpack carriage. Eighteen conditions were established which consisted of the two modes of carriage and a combination of three load masses (9kg, 12kg and 15kg) and three gradients (5%, 10% and 15%). Twenty eight Rhodes University female students comprised the sample and the experimental procedures were conducted on a Quinton treadmill. Each participant was required to complete nine of the eighteen conditions which were each four minutes in duration. Postural changes were assessed using lateral and posterior digital images taken at the second and fourth minute and compression and shearing forces were estimated with the ErgolmagerTM Physiological responses (heart rate, ventilation and metabolic responses) were measured continuously with the Quark b² and perceptual responses ('central' and 'local' RPE) were measured every minute during the experimentation and body discomfort was rated at the completion of each condition. Overall responses revealed that hand carriage (146 bt.min⁻¹ , 25.09 mIO₂. kg-l.min⁻¹) was generally found to be more physiologically stressful than backpack carriage (130 bt.min⁻¹, 22.15 mIO₂.kg⁻¹ .min⁻¹) independent of load mass and gradient. Physiological responses were higher (113 bt.min-1 to 174 bt.min⁻¹ ) in responses to increasing gradient as opposed to increasing load mass (104 bt.min-1 to 153 bt.min⁻¹ ) for both backpack and hand carriage. Categorisation using the guidelines of Sanders and McCormick (1993) allowed for classification of conditions, with respect to physiological responses, into 'moderate', 'heavy' and 'very heavy' stress. For almost all of the physiological responses the majority of conditions which were classified as 'moderate' were backpack carriage conditions and the conditions classified as 'very heavy' were mostly hand carriage conditions. In terms of postural responses hand carriage resulted in more strain and greater compression and shearing forces on the spine. In terms of the compression forces increasing gradient had a greater affect on backpack carriage (681 N to 935 N) compared to hand carriage (570N to 793N). In contrast, increasing load mass had a larger affect on hand carriage postures and compression forces (751 N to 935N) in comparison to backpack carriage (723N to 780N). Shearing forces were found to be worse in hand carriage conditions overall. Although participants generally underrated perceived exertion in relation to cardiorespiratory responses, these perceptions revealed that backpack carriage, with a mean 'central' RPE of 12 compared to 11 for hand carriage, was somewhat preferred to hand carriage and that increasing gradient was perceived to be marginally more straining than increasing load mass.
- Full Text:
- Date Issued: 2007
Lack of genetic differentiation among four sympatric southeast African intertidal limpets (Siphonariidae): phenotypic plasticity in a single species?
- Teske, Peter R, Barker, Nigel P, McQuaid, Christopher D
- Authors: Teske, Peter R , Barker, Nigel P , McQuaid, Christopher D
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445461 , vital:74390 , https://doi.org/10.1093/mollus/eym012
- Description: Specimens of four sympatric intertidal limpet species (Siphonaria dayi, S. tenuicostulata, S. anneae and S. nigerrima) were collected from four localities on the east coast of South Africa and southern Mozambique. Their phylogenetic relationships were investigated using sequences of the mitochondrial COI gene and the intron-containing nuclear ATPSβ gene. Two closely related lineages were recovered, which grouped specimens on the basis of geography rather than morphology. One lineage was associated with the subtropical coastline of South Africa's east coast and the other with the tropical coastline of northeastern South Africa and southern Mozambique. This genetic discontinuity coincides with a biogeographic boundary located in the vicinity of Cape St Lucia. Combined genetic diversity of the four species was lower than that of three other southern African congeners, and fell within the range determined for single southern African marine mollusc species. We suggest that the four limpet species are in fact different morphotypes of a single species.
- Full Text:
- Date Issued: 2007
- Authors: Teske, Peter R , Barker, Nigel P , McQuaid, Christopher D
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445461 , vital:74390 , https://doi.org/10.1093/mollus/eym012
- Description: Specimens of four sympatric intertidal limpet species (Siphonaria dayi, S. tenuicostulata, S. anneae and S. nigerrima) were collected from four localities on the east coast of South Africa and southern Mozambique. Their phylogenetic relationships were investigated using sequences of the mitochondrial COI gene and the intron-containing nuclear ATPSβ gene. Two closely related lineages were recovered, which grouped specimens on the basis of geography rather than morphology. One lineage was associated with the subtropical coastline of South Africa's east coast and the other with the tropical coastline of northeastern South Africa and southern Mozambique. This genetic discontinuity coincides with a biogeographic boundary located in the vicinity of Cape St Lucia. Combined genetic diversity of the four species was lower than that of three other southern African congeners, and fell within the range determined for single southern African marine mollusc species. We suggest that the four limpet species are in fact different morphotypes of a single species.
- Full Text:
- Date Issued: 2007
Land reform policies and human rights : a South African case study
- Fabbriciani, Antonio Antonino
- Authors: Fabbriciani, Antonio Antonino
- Date: 2007
- Subjects: Land reform -- South Africa -- Case studies , Human rights -- South Africa -- Case studies
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: vital:9042 , http://hdl.handle.net/10948/502 , Land reform -- South Africa -- Case studies , Human rights -- South Africa -- Case studies
- Description: This treatise begins with a discussion of different clauses of the Bill of Rights in the South African Constitution and the land reform policies of the South African government. The inequality and injustice caused by decades of apartheid land law forms the background of the land reform programme. The treatise addresses the consequences of this legacy on the implementation of the South African Constitution including the right to property. The discussion includes the three key elements of the land reform programme namely restitution, redistribution and tenure reform. The content of this treatise ranges over these three elements of land reform, applying constitutional issues to the relevant case law, The balancing and the reconciliation of rights and interest between the individual and the public in a just manner will be the barometer. The conclusion shows that the Constitution both protects existing rights and authorises the promotion of land reform within the framework of Section 25 of the Constitution, and that every aspect of the property clause has to be regarded as part of a constitional effort in balancing individual interest and public interest in terms of a constitutional order. It is my sincere hope that this treatise will contribute toward the achievement of equity, stability and by the values of an open and democratic society based on human dignity, freedom and human rights.
- Full Text:
- Date Issued: 2007
- Authors: Fabbriciani, Antonio Antonino
- Date: 2007
- Subjects: Land reform -- South Africa -- Case studies , Human rights -- South Africa -- Case studies
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: vital:9042 , http://hdl.handle.net/10948/502 , Land reform -- South Africa -- Case studies , Human rights -- South Africa -- Case studies
- Description: This treatise begins with a discussion of different clauses of the Bill of Rights in the South African Constitution and the land reform policies of the South African government. The inequality and injustice caused by decades of apartheid land law forms the background of the land reform programme. The treatise addresses the consequences of this legacy on the implementation of the South African Constitution including the right to property. The discussion includes the three key elements of the land reform programme namely restitution, redistribution and tenure reform. The content of this treatise ranges over these three elements of land reform, applying constitutional issues to the relevant case law, The balancing and the reconciliation of rights and interest between the individual and the public in a just manner will be the barometer. The conclusion shows that the Constitution both protects existing rights and authorises the promotion of land reform within the framework of Section 25 of the Constitution, and that every aspect of the property clause has to be regarded as part of a constitional effort in balancing individual interest and public interest in terms of a constitutional order. It is my sincere hope that this treatise will contribute toward the achievement of equity, stability and by the values of an open and democratic society based on human dignity, freedom and human rights.
- Full Text:
- Date Issued: 2007
Language policy and planning: general constraints and pressures
- Authors: Wright, Laurence
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:7043 , http://hdl.handle.net/10962/d1007385
- Description: preprint , The general idea of language policy and planning is easily expressed. Christopher Brumfit, for one, defines language planning as “The attempt to control the use, status, and structure of a language through a language policy developed by a government or other authority” (see the Oxford Companion to the English Language). The Random House Dictionary of the English Language concurs, but adds some detail: language planning is “the development of policies or programmes designed to direct or change language use, as through the establishment of an official language, the standardization or modernization of a language, or the development or alteration of a writing system”. Such definitions could easily be multiplied, and they differ only slightly in nuance and depth.Language Policy is the formal, often legally entrenched, expression of language planning.
- Full Text:
- Date Issued: 2007
- Authors: Wright, Laurence
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:7043 , http://hdl.handle.net/10962/d1007385
- Description: preprint , The general idea of language policy and planning is easily expressed. Christopher Brumfit, for one, defines language planning as “The attempt to control the use, status, and structure of a language through a language policy developed by a government or other authority” (see the Oxford Companion to the English Language). The Random House Dictionary of the English Language concurs, but adds some detail: language planning is “the development of policies or programmes designed to direct or change language use, as through the establishment of an official language, the standardization or modernization of a language, or the development or alteration of a writing system”. Such definitions could easily be multiplied, and they differ only slightly in nuance and depth.Language Policy is the formal, often legally entrenched, expression of language planning.
- Full Text:
- Date Issued: 2007
Lazarus in the Constitutional Court: an exhumation of the exceptio doli generalis
- Authors: Glover, Graham B
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70678 , vital:29688 , https://hdl.handle.net/10520/EJC53775
- Description: A landmark moment in the history of South African contract law was the emphatic interment of the exceptio doli generalis by Joubert JA in Bank of Lisbon and South Africa v De Ornelas 1988 (3) SA580 (A). Throughout most of the twentieth century, the exceptio doli generalis had been viewed as an equitable defence that allowed a defendant to resist a claim for performance under a contract when there was something unconscionable about the plaintiff's seeking to enforce the contract (or a clause thereof) in the specific circumstances of that case (see A J Kerr Principles of the Law of Contract 6 ed (2002) 637ff; P J Aronstam 'Unconscionable contracts: The South African solution?' (1979) 42 THRHR 21; P van Warmelo 'Exceptio doli' 1981 De Jure 202).
- Full Text: false
- Date Issued: 2007
- Authors: Glover, Graham B
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70678 , vital:29688 , https://hdl.handle.net/10520/EJC53775
- Description: A landmark moment in the history of South African contract law was the emphatic interment of the exceptio doli generalis by Joubert JA in Bank of Lisbon and South Africa v De Ornelas 1988 (3) SA580 (A). Throughout most of the twentieth century, the exceptio doli generalis had been viewed as an equitable defence that allowed a defendant to resist a claim for performance under a contract when there was something unconscionable about the plaintiff's seeking to enforce the contract (or a clause thereof) in the specific circumstances of that case (see A J Kerr Principles of the Law of Contract 6 ed (2002) 637ff; P J Aronstam 'Unconscionable contracts: The South African solution?' (1979) 42 THRHR 21; P van Warmelo 'Exceptio doli' 1981 De Jure 202).
- Full Text: false
- Date Issued: 2007
Learning in a Changing World
- Lotz-Sisitka, Heila, O'Donoghue, Rob B, Robottom, Ian
- Authors: Lotz-Sisitka, Heila , O'Donoghue, Rob B , Robottom, Ian
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182679 , vital:43853 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122733 "
- Description: The year 2007 is a significant year for environmental education. It marks 30 years since the first internationally agreed principles of environmental education were developed at Tbilisi, commonly known as the Tbilisi Principles. It is also the year in which human beings apparently are finally ‘waking up’ to the fact that human-induced environmental change is causing impacts which are infinitely complex and difficult to resolve. This year, through various highly publicised and politicised events, people have begun to recognise that it is getting hot on planet Earth, and that the associated social, economic and environmental costs are profoundly disturbing. The Stern Review and the UN Intergovernmental Panel on Climate Change both firmly indicated that human-induced environmental change will threaten human economies and security in ways that are unprecedented in human history. Southern Africa, where this special edition of the EEASA Journal is being produced to coincide with the 25th anniversary of the existence of the Environmental Education Association of Southern Africa, and the hosting of the 4th World Environmental Education Congress, is one of the areas most vulnerable to the impacts of climate change. More than 70% of the people in southern Africa live in rural areas, and depend directly on natural resources for their livelihood and food security, making environment (and environmental education processes) a central concern in development discussions in the region. Patterns of global inequality are pronounced in the region, which has some of the poorest countries in the world. Out of its 25-year history, EEASA and its members, along with colleagues around the world, continue to seek ways of educating and empowering people to successfully participate in resolving environmental issues and create more sustainable and socially just living patterns. In drawing attention to our constant need to learn how to improve our understandings of environmental education and learning as the world around us changes, the World Environmental Education Congress organising committee chose to profile the question of ‘Learning in a Changing World’, by making this the theme of the Congress.
- Full Text:
- Date Issued: 2007
- Authors: Lotz-Sisitka, Heila , O'Donoghue, Rob B , Robottom, Ian
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182679 , vital:43853 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122733 "
- Description: The year 2007 is a significant year for environmental education. It marks 30 years since the first internationally agreed principles of environmental education were developed at Tbilisi, commonly known as the Tbilisi Principles. It is also the year in which human beings apparently are finally ‘waking up’ to the fact that human-induced environmental change is causing impacts which are infinitely complex and difficult to resolve. This year, through various highly publicised and politicised events, people have begun to recognise that it is getting hot on planet Earth, and that the associated social, economic and environmental costs are profoundly disturbing. The Stern Review and the UN Intergovernmental Panel on Climate Change both firmly indicated that human-induced environmental change will threaten human economies and security in ways that are unprecedented in human history. Southern Africa, where this special edition of the EEASA Journal is being produced to coincide with the 25th anniversary of the existence of the Environmental Education Association of Southern Africa, and the hosting of the 4th World Environmental Education Congress, is one of the areas most vulnerable to the impacts of climate change. More than 70% of the people in southern Africa live in rural areas, and depend directly on natural resources for their livelihood and food security, making environment (and environmental education processes) a central concern in development discussions in the region. Patterns of global inequality are pronounced in the region, which has some of the poorest countries in the world. Out of its 25-year history, EEASA and its members, along with colleagues around the world, continue to seek ways of educating and empowering people to successfully participate in resolving environmental issues and create more sustainable and socially just living patterns. In drawing attention to our constant need to learn how to improve our understandings of environmental education and learning as the world around us changes, the World Environmental Education Congress organising committee chose to profile the question of ‘Learning in a Changing World’, by making this the theme of the Congress.
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- Date Issued: 2007
Lessons from the dead masters: Wordsworth and Byron in J. M. Coetzee's Disgrace
- Authors: Beard, Margot
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6114 , http://hdl.handle.net/10962/d1003827
- Description: As one whose research interests lie in the field of Romanticism, most specifically Wordsworth and Byron, I was obviously intrigued by J. M. Coetzee's use of these poets in Disgrace. Subsequent readings of the work have convinced me that more attention needs to be paid to the deeper implications of their presence in the text. Certainly many scholars have explored the significance of David Lurie's professional interest in the Romantic poets and the novel's imbeddedness in what Jane Taylor has referred to as "the European Enlightenment's legacy of the autonomy of the individual" as well as a specifically "eighteenth century model of philosophical sympathy" (1999, 25). Yet I feel that insufficient attention has been paid to the significance of Romanticism, the Wordsworthian and the Byronic in the novel. Generally, the commentary ranges from seeing Lurie's academic interests as symptomatic of his white colonialist mentality to a more nuanced but insufficiently developed focus on the possibilities lying behind Coetzee's startling juxtaposition of two of the most famed and yet most overtly antagonistic of the Romantic poets. Zoë Wicomb is representative of the first approach. In her estimation, Lurie may be rejected since he "looks to Europe as the centre of reference" and "our feelings and experiences of nature need not be structured by poetic discourses from the metropolis".
- Full Text:
- Date Issued: 2007
- Authors: Beard, Margot
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6114 , http://hdl.handle.net/10962/d1003827
- Description: As one whose research interests lie in the field of Romanticism, most specifically Wordsworth and Byron, I was obviously intrigued by J. M. Coetzee's use of these poets in Disgrace. Subsequent readings of the work have convinced me that more attention needs to be paid to the deeper implications of their presence in the text. Certainly many scholars have explored the significance of David Lurie's professional interest in the Romantic poets and the novel's imbeddedness in what Jane Taylor has referred to as "the European Enlightenment's legacy of the autonomy of the individual" as well as a specifically "eighteenth century model of philosophical sympathy" (1999, 25). Yet I feel that insufficient attention has been paid to the significance of Romanticism, the Wordsworthian and the Byronic in the novel. Generally, the commentary ranges from seeing Lurie's academic interests as symptomatic of his white colonialist mentality to a more nuanced but insufficiently developed focus on the possibilities lying behind Coetzee's startling juxtaposition of two of the most famed and yet most overtly antagonistic of the Romantic poets. Zoë Wicomb is representative of the first approach. In her estimation, Lurie may be rejected since he "looks to Europe as the centre of reference" and "our feelings and experiences of nature need not be structured by poetic discourses from the metropolis".
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- Date Issued: 2007
Light on a hill: building the Constitutional Court of South Africa, Bronwyn Law-Viljoen (Ed.): book review
- Authors: Simbao, Ruth K
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147324 , vital:38626 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC31011
- Description: Light on a hill : Building the Constitutional Court of South Africa is a visually elegant book that claims to 'reflect the spirit of the Court and be a beautiful object in its own right' (p. 8). Certainly this book is striking, with its rich photographs by Angela Buckland, its fresh, breathable design by Adele Prins, and its broad format with lavish centerfolds. Reading the text is in many ways an enlightening process of understanding the conceptual underpinnings of the buildings that make up the Constitutional Court complex, but this process of reading takes a few twists and turns along the way.
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- Date Issued: 2007
- Authors: Simbao, Ruth K
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147324 , vital:38626 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC31011
- Description: Light on a hill : Building the Constitutional Court of South Africa is a visually elegant book that claims to 'reflect the spirit of the Court and be a beautiful object in its own right' (p. 8). Certainly this book is striking, with its rich photographs by Angela Buckland, its fresh, breathable design by Adele Prins, and its broad format with lavish centerfolds. Reading the text is in many ways an enlightening process of understanding the conceptual underpinnings of the buildings that make up the Constitutional Court complex, but this process of reading takes a few twists and turns along the way.
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- Date Issued: 2007
Limiting vulnerability exposure through effective patch management: threat mitigation through vulnerability remediation
- Authors: White, Dominic Stjohn Dolin
- Date: 2007 , 2007-02-08
- Subjects: Computer networks -- Security measures , Computer viruses , Computer security
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4629 , http://hdl.handle.net/10962/d1006510 , Computer networks -- Security measures , Computer viruses , Computer security
- Description: This document aims to provide a complete discussion on vulnerability and patch management. The first chapters look at the trends relating to vulnerabilities, exploits, attacks and patches. These trends describe the drivers of patch and vulnerability management and situate the discussion in the current security climate. The following chapters then aim to present both policy and technical solutions to the problem. The policies described lay out a comprehensive set of steps that can be followed by any organisation to implement their own patch management policy, including practical advice on integration with other policies, managing risk, identifying vulnerability, strategies for reducing downtime and generating metrics to measure progress. Having covered the steps that can be taken by users, a strategy describing how best a vendor should implement a related patch release policy is provided. An argument is made that current monthly patch release schedules are inadequate to allow users to most effectively and timeously mitigate vulnerabilities. The final chapters discuss the technical aspect of automating parts of the policies described. In particular the concept of 'defense in depth' is used to discuss additional strategies for 'buying time' during the patch process. The document then goes on to conclude that in the face of increasing malicious activity and more complex patching, solid frameworks such as those provided in this document are required to ensure an organisation can fully manage the patching process. However, more research is required to fully understand vulnerabilities and exploits. In particular more attention must be paid to threats, as little work as been done to fully understand threat-agent capabilities and activities from a day to day basis. , TeX output 2007.02.08:2212 , Adobe Acrobat 9.51 Paper Capture Plug-in
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- Date Issued: 2007
- Authors: White, Dominic Stjohn Dolin
- Date: 2007 , 2007-02-08
- Subjects: Computer networks -- Security measures , Computer viruses , Computer security
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4629 , http://hdl.handle.net/10962/d1006510 , Computer networks -- Security measures , Computer viruses , Computer security
- Description: This document aims to provide a complete discussion on vulnerability and patch management. The first chapters look at the trends relating to vulnerabilities, exploits, attacks and patches. These trends describe the drivers of patch and vulnerability management and situate the discussion in the current security climate. The following chapters then aim to present both policy and technical solutions to the problem. The policies described lay out a comprehensive set of steps that can be followed by any organisation to implement their own patch management policy, including practical advice on integration with other policies, managing risk, identifying vulnerability, strategies for reducing downtime and generating metrics to measure progress. Having covered the steps that can be taken by users, a strategy describing how best a vendor should implement a related patch release policy is provided. An argument is made that current monthly patch release schedules are inadequate to allow users to most effectively and timeously mitigate vulnerabilities. The final chapters discuss the technical aspect of automating parts of the policies described. In particular the concept of 'defense in depth' is used to discuss additional strategies for 'buying time' during the patch process. The document then goes on to conclude that in the face of increasing malicious activity and more complex patching, solid frameworks such as those provided in this document are required to ensure an organisation can fully manage the patching process. However, more research is required to fully understand vulnerabilities and exploits. In particular more attention must be paid to threats, as little work as been done to fully understand threat-agent capabilities and activities from a day to day basis. , TeX output 2007.02.08:2212 , Adobe Acrobat 9.51 Paper Capture Plug-in
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- Date Issued: 2007