Effects of polymerisation conditions on the mechanism and properties of furfuryl alcohol resin
- Authors: Iroegbu, Austine Ofondu
- Date: 2018
- Subjects: Polymerization , Polyethylene
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/30386 , vital:30937
- Description: The purpose of this study was to do a comparative investigation on the acid- and heat catalysed polymerisation and resinification of furfuryl alcohol and the effects of these polymerisation conditions on the mechanism, morphology, molecular weight and thermal properties of the polyfurfuryl alcohol resins. The formation of furfuryl alcohol polymers was confirmed using size exclusion chromatography (SEC); the synthesised polymer resins were investigated using Fourier transform infrared spectroscopy (FTIR,), scanning electron microscopy (SEM) and Thermogravimetric analysis (TGA). The effects of polymerisation conditions on the mechanism of polyfurfuryl alcohol polymerisation was a major focus of this study. The obtained results confirm that the surface topology, mechanism of polymerisation, thermal behaviour and molecular weights of polyfurfuryl alcohol polymer resins are dependent on the polymerisation condition. The acid and heat catalysed polyfurfuryl alcohol resin polymers presented interesting and promising results.
- Full Text:
- Date Issued: 2018
- Authors: Iroegbu, Austine Ofondu
- Date: 2018
- Subjects: Polymerization , Polyethylene
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/30386 , vital:30937
- Description: The purpose of this study was to do a comparative investigation on the acid- and heat catalysed polymerisation and resinification of furfuryl alcohol and the effects of these polymerisation conditions on the mechanism, morphology, molecular weight and thermal properties of the polyfurfuryl alcohol resins. The formation of furfuryl alcohol polymers was confirmed using size exclusion chromatography (SEC); the synthesised polymer resins were investigated using Fourier transform infrared spectroscopy (FTIR,), scanning electron microscopy (SEM) and Thermogravimetric analysis (TGA). The effects of polymerisation conditions on the mechanism of polyfurfuryl alcohol polymerisation was a major focus of this study. The obtained results confirm that the surface topology, mechanism of polymerisation, thermal behaviour and molecular weights of polyfurfuryl alcohol polymer resins are dependent on the polymerisation condition. The acid and heat catalysed polyfurfuryl alcohol resin polymers presented interesting and promising results.
- Full Text:
- Date Issued: 2018
Effects of production systems and canola meal supplementation on carcass and meat quality characteristics of spent laying hens
- Authors: Semwogerere, Farouk
- Date: 2018
- Subjects: Broilers (Chickens) -- Feeding and feeds Chickens -- Feeding and feeds Chicken industry -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/9242 , vital:34309
- Description: This study evaluated the carcass and meat quality traits of spent laying hens as influenced by production systems (conventional cages and free range) and the inclusion/exclusion of canola meal in their diets. A total of 30 free range and 60 battery cage reared Lohmann Brown-Elite spent laying hens were obtained from a commercial egg producer. The 30 free range hens (53 weeks of age) and 30 of the caged hens (40 weeks of age) were fed a conventional diet, while the remaining 30 caged hens (48 weeks of age) were fed a diet supplemented with canola meal (20 percent). Carcass, portion and organ weights were determined. Physical attributes and proximate composition were analyzed for, with additional fatty acids and sensory profiles being determined for the effects of canola meal inclusion in the diet. Caged hens had heavier (P ≤ 0.05) warm and cold carcasses, thigh, wing and feet compared to free range hens. The percentages of the breast (26.1 ± 0.51 vs. 28.3 ± 0.28), drum, breast bones, breast thaw and cooking losses and thigh cooking loss were lower (P ≤ 0.05) for caged hens than for free range hens. Free range hens had heavier (P ≤ 0.05) gizzards (33.9 ± 1.04 vs. 30.5 ± 0.73) and bones and a lower (P ≤ 0.05) breast meat percentage (47.3 ± 0.94 vs. 51.7 ± 1.35). Meat redness (a*) (0.54 ± 0.222 vs. 1.40 ± 0.135) and hue angle value, skin redness (a*), breast and thigh, Warner-Bratzler shear force (WBSF) values (breast: 12.37 ± 0.411 vs. 17.10 ± 0.751, thigh: 29.68 ± 0.306 vs. 39.75 ± 0.826), breast moisture and thigh ash content were lower (P ≤ 0.05) for caged hens than free range hens. Caged hens had higher (P ≤ 0.05) thigh thaw loss and breast ash content than free range hens. Canola-fed hens had higher (P ≤ 0.05) drum percentages, breast bone weights and percentages, with lower (P ≤ 0.05) thigh and breast meat percentages. Canola-fed hens had lower (P ≤ 0.05) thaw losses, skin yellowness (b*) and Chroma values, breast fat content with higher cooking losses, skin redness (a*) and hue angle value, as well as breast WBSF (12.37 ± 0.411 vs. 15.43 ± 0.600). Palmitic acid, stearic acid, heneicosanoic acid acid, palmitoleic acid, saturated fatty acids (SFA) (34.0 ± 0.56 vs. 38.7 ± 0.71), n-6:n-3 polyunsaturated fatty acids (PUFA) ratio (5.5 ± 0.13 vs. 7.2 ± 0.28), atherogenic index (IA), thrombogenic index (IT), delta-5 desaturase (D5D, elongase index and thiosterase index were lower (P ≤ 0.05) for canola-fed hen breast meat. Breast meat from conventionally fed hens had lower (P ≤ 0.05) myristic acid, lignoceric acid, nervonic acid, alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), PUFA:SFA ratio (0.7 ± 0.05 vs. 0.9 ± 0.02), n-3 PUFA (3.4 ± 0.31 vs. 5.1 ± 0.17), hypocholesterolemic:Hypercholesterolaemic (h/H), stearoyl-CoA desaturase 16 (SCD16) and stearoyl-CoA desaturase 18 (SCD18). The breast meat from conventionally fed hens had lower (P ≤ 0.05) metallic flavor than that from canola-fed hens. Strong positive correlations were observed for overall aroma with chicken (r = 0.965, P < 0.001) and brothy aroma (r = 0.827, P < 0.001); overall aroma with overall flavor (r = 0.680, P < 0.001), chicken flavor (r = 0.668, P < 0.001) and brothy flavor (r = 0.548, P = 0.006); initial juiciness with sustained juiciness (r = 0.771, P < 0.001) and tenderness (r = 0.537, P = 0.007); sustained juiciness with tenderness (r = 0.790, P < 0.001) and chewiness with residue (r = 0.783, P < 0.001). Whilst strong negative correlations were observed for: sustained juiciness with chewiness (r = -0.655, P = 0.001) and residue (r = 0.783, P < 0.001) and for tenderness with chewiness (r = 0.845, P < 0.001) and residue (r = -0.855, P < 0.001). Results of this study highlight that a free range production system when compared to a conventional cage system increased undesirable carcass and physical meat traits of spent laying hens. On the other hand, canola meal inclusion incorporates beneficial health aspects without affecting the sensory profile of meat derived from spent laying hens, both groups of hens being reared in battery cage system. Spent laying hen breasts can be consumed as a functional food (especially canolafed) since the fat content and composition was observed to be close to that which is recommended for a healthy diet.
- Full Text:
- Date Issued: 2018
- Authors: Semwogerere, Farouk
- Date: 2018
- Subjects: Broilers (Chickens) -- Feeding and feeds Chickens -- Feeding and feeds Chicken industry -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/9242 , vital:34309
- Description: This study evaluated the carcass and meat quality traits of spent laying hens as influenced by production systems (conventional cages and free range) and the inclusion/exclusion of canola meal in their diets. A total of 30 free range and 60 battery cage reared Lohmann Brown-Elite spent laying hens were obtained from a commercial egg producer. The 30 free range hens (53 weeks of age) and 30 of the caged hens (40 weeks of age) were fed a conventional diet, while the remaining 30 caged hens (48 weeks of age) were fed a diet supplemented with canola meal (20 percent). Carcass, portion and organ weights were determined. Physical attributes and proximate composition were analyzed for, with additional fatty acids and sensory profiles being determined for the effects of canola meal inclusion in the diet. Caged hens had heavier (P ≤ 0.05) warm and cold carcasses, thigh, wing and feet compared to free range hens. The percentages of the breast (26.1 ± 0.51 vs. 28.3 ± 0.28), drum, breast bones, breast thaw and cooking losses and thigh cooking loss were lower (P ≤ 0.05) for caged hens than for free range hens. Free range hens had heavier (P ≤ 0.05) gizzards (33.9 ± 1.04 vs. 30.5 ± 0.73) and bones and a lower (P ≤ 0.05) breast meat percentage (47.3 ± 0.94 vs. 51.7 ± 1.35). Meat redness (a*) (0.54 ± 0.222 vs. 1.40 ± 0.135) and hue angle value, skin redness (a*), breast and thigh, Warner-Bratzler shear force (WBSF) values (breast: 12.37 ± 0.411 vs. 17.10 ± 0.751, thigh: 29.68 ± 0.306 vs. 39.75 ± 0.826), breast moisture and thigh ash content were lower (P ≤ 0.05) for caged hens than free range hens. Caged hens had higher (P ≤ 0.05) thigh thaw loss and breast ash content than free range hens. Canola-fed hens had higher (P ≤ 0.05) drum percentages, breast bone weights and percentages, with lower (P ≤ 0.05) thigh and breast meat percentages. Canola-fed hens had lower (P ≤ 0.05) thaw losses, skin yellowness (b*) and Chroma values, breast fat content with higher cooking losses, skin redness (a*) and hue angle value, as well as breast WBSF (12.37 ± 0.411 vs. 15.43 ± 0.600). Palmitic acid, stearic acid, heneicosanoic acid acid, palmitoleic acid, saturated fatty acids (SFA) (34.0 ± 0.56 vs. 38.7 ± 0.71), n-6:n-3 polyunsaturated fatty acids (PUFA) ratio (5.5 ± 0.13 vs. 7.2 ± 0.28), atherogenic index (IA), thrombogenic index (IT), delta-5 desaturase (D5D, elongase index and thiosterase index were lower (P ≤ 0.05) for canola-fed hen breast meat. Breast meat from conventionally fed hens had lower (P ≤ 0.05) myristic acid, lignoceric acid, nervonic acid, alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), PUFA:SFA ratio (0.7 ± 0.05 vs. 0.9 ± 0.02), n-3 PUFA (3.4 ± 0.31 vs. 5.1 ± 0.17), hypocholesterolemic:Hypercholesterolaemic (h/H), stearoyl-CoA desaturase 16 (SCD16) and stearoyl-CoA desaturase 18 (SCD18). The breast meat from conventionally fed hens had lower (P ≤ 0.05) metallic flavor than that from canola-fed hens. Strong positive correlations were observed for overall aroma with chicken (r = 0.965, P < 0.001) and brothy aroma (r = 0.827, P < 0.001); overall aroma with overall flavor (r = 0.680, P < 0.001), chicken flavor (r = 0.668, P < 0.001) and brothy flavor (r = 0.548, P = 0.006); initial juiciness with sustained juiciness (r = 0.771, P < 0.001) and tenderness (r = 0.537, P = 0.007); sustained juiciness with tenderness (r = 0.790, P < 0.001) and chewiness with residue (r = 0.783, P < 0.001). Whilst strong negative correlations were observed for: sustained juiciness with chewiness (r = -0.655, P = 0.001) and residue (r = 0.783, P < 0.001) and for tenderness with chewiness (r = 0.845, P < 0.001) and residue (r = -0.855, P < 0.001). Results of this study highlight that a free range production system when compared to a conventional cage system increased undesirable carcass and physical meat traits of spent laying hens. On the other hand, canola meal inclusion incorporates beneficial health aspects without affecting the sensory profile of meat derived from spent laying hens, both groups of hens being reared in battery cage system. Spent laying hen breasts can be consumed as a functional food (especially canolafed) since the fat content and composition was observed to be close to that which is recommended for a healthy diet.
- Full Text:
- Date Issued: 2018
Effects of the carboxylic acid substituents on the photophysical and nonlinear optical properties of asymmetrical Zn (II) phthalocyanines–quantum dots conjugates
- Mgidlana, Sithi, Oluwole, David O, Nyokong, Tebello
- Authors: Mgidlana, Sithi , Oluwole, David O , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187662 , vital:44684 , xlink:href="https://doi.org/10.1080/24701556.2018.1503684"
- Description: This work reports on three asymmetrical Zn(II) phthalocyanines, namely: zinc(II) 3–(4-phenoxy)propanoic acid) phthalocyanine(1), zinc(II) 3–(4-phenoxy carboxylic acid) phthalocyanine (2) and zinc(II) 3–(4–oxy)phenoxy)acetic acid phthalocyanine (3) when covalently linked to glutathione(GSH) capped CdTe/ZnSe and CdTe/ZnSe/ZnO quantum dots (QDs). Of the Pc complexes alone, 1 afforded the highest triplet quantum yield (ΦT) value of 0.67 with corresponding largest nonlinear absorption coefficient (βeff) value of 14.0 cm/GW compared to 2 and 3. The conjugates afforded improved triplet quantum yield and nonlinear optical behavior in comparison to the Pc complexes alone.
- Full Text:
- Date Issued: 2018
- Authors: Mgidlana, Sithi , Oluwole, David O , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187662 , vital:44684 , xlink:href="https://doi.org/10.1080/24701556.2018.1503684"
- Description: This work reports on three asymmetrical Zn(II) phthalocyanines, namely: zinc(II) 3–(4-phenoxy)propanoic acid) phthalocyanine(1), zinc(II) 3–(4-phenoxy carboxylic acid) phthalocyanine (2) and zinc(II) 3–(4–oxy)phenoxy)acetic acid phthalocyanine (3) when covalently linked to glutathione(GSH) capped CdTe/ZnSe and CdTe/ZnSe/ZnO quantum dots (QDs). Of the Pc complexes alone, 1 afforded the highest triplet quantum yield (ΦT) value of 0.67 with corresponding largest nonlinear absorption coefficient (βeff) value of 14.0 cm/GW compared to 2 and 3. The conjugates afforded improved triplet quantum yield and nonlinear optical behavior in comparison to the Pc complexes alone.
- Full Text:
- Date Issued: 2018
Efficient Biometric Access Control for Larger Scale Populations
- Brown, Dane L, Bradshaw, Karen L
- Authors: Brown, Dane L , Bradshaw, Karen L
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/465667 , vital:76630 , xlink:href="https://www.researchgate.net/profile/Dane-Brown-2/publication/335378829_Efficient_Biometric_Access_Control_for_Larger_Scale_Populations/links/5d61159ea6fdccc32ccd2c8a/Efficient-Biometric-Access-Control-for-Larger-Scale-Populations.pdf"
- Description: Biometric applications and databases are growing at an alarming rate. Processing large or complex biometric data induces longer wait times that can limit usability during application. This paper focuses on increasing the processing speed of biometric data, and calls for a parallel approach to data processing that is beyond the capability of a central processing unit (CPU). The graphical processing unit (GPU) is effectively utilized with compute unified device architecture (CUDA), and results in at least triple the processing speed when compared with a previously presented accurate and secure multimodal biometric system. When saturating the CPU-only implementation with more individuals than the available thread count, the GPU-assisted implementation outperforms it exponentially. The GPU-assisted implementation is also validated to have the same accuracy of the original system, and thus shows promising advancements in both accuracy and processing speed in the challenging big data world.
- Full Text:
- Date Issued: 2018
- Authors: Brown, Dane L , Bradshaw, Karen L
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/465667 , vital:76630 , xlink:href="https://www.researchgate.net/profile/Dane-Brown-2/publication/335378829_Efficient_Biometric_Access_Control_for_Larger_Scale_Populations/links/5d61159ea6fdccc32ccd2c8a/Efficient-Biometric-Access-Control-for-Larger-Scale-Populations.pdf"
- Description: Biometric applications and databases are growing at an alarming rate. Processing large or complex biometric data induces longer wait times that can limit usability during application. This paper focuses on increasing the processing speed of biometric data, and calls for a parallel approach to data processing that is beyond the capability of a central processing unit (CPU). The graphical processing unit (GPU) is effectively utilized with compute unified device architecture (CUDA), and results in at least triple the processing speed when compared with a previously presented accurate and secure multimodal biometric system. When saturating the CPU-only implementation with more individuals than the available thread count, the GPU-assisted implementation outperforms it exponentially. The GPU-assisted implementation is also validated to have the same accuracy of the original system, and thus shows promising advancements in both accuracy and processing speed in the challenging big data world.
- Full Text:
- Date Issued: 2018
Electrocatalytic activity of a push-pull phthalocyanine in the presence of reduced and amino functionalized graphene quantum dots towards the electrooxidation of hydrazine
- Centane, Sixolile, Sekhosana, Kutloano E, Matshitse, Refilwe, Nyokong, Tebello
- Authors: Centane, Sixolile , Sekhosana, Kutloano E , Matshitse, Refilwe , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/233456 , vital:50092 , xlink:href="https://doi.org/10.1016/j.jelechem.2018.05.005"
- Description: We report on the electrochemical behaviour of reduced graphene quantum dots (rGQDs) compared to amino functionalized graphene quantum dots (NH2GQDs). Reduction of the GQDs entails the elimination of the excessive carboxyl and hydrogen groups on the GQDs surface, thereby reducing the energy band gap. The energy band gap of graphene is directly proportional to the available oxygen atoms. The two GQD types were conjugated to a novel cobalt phthalocyanine (cobalt tris-(tert-butyl phenoxy)-mono-carboxyphenoxy phthalocyanine, CoPc) via covalent and nom-covalent interactions. The resulting conjugates were tested towards the electrooxidation of hydrazine. The conjugates are represented as rGQDs(π)CoPc, NH2(π)CoPc, rGQDs@CoPc and NH2GQDs@CoPc. The resulting conjugates were adsorbed onto a glassy carbon electrode using the drop and dry method. The lowest limit of detection (LOD) was obtained for rGQDs(π)CoPc.
- Full Text:
- Date Issued: 2018
- Authors: Centane, Sixolile , Sekhosana, Kutloano E , Matshitse, Refilwe , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/233456 , vital:50092 , xlink:href="https://doi.org/10.1016/j.jelechem.2018.05.005"
- Description: We report on the electrochemical behaviour of reduced graphene quantum dots (rGQDs) compared to amino functionalized graphene quantum dots (NH2GQDs). Reduction of the GQDs entails the elimination of the excessive carboxyl and hydrogen groups on the GQDs surface, thereby reducing the energy band gap. The energy band gap of graphene is directly proportional to the available oxygen atoms. The two GQD types were conjugated to a novel cobalt phthalocyanine (cobalt tris-(tert-butyl phenoxy)-mono-carboxyphenoxy phthalocyanine, CoPc) via covalent and nom-covalent interactions. The resulting conjugates were tested towards the electrooxidation of hydrazine. The conjugates are represented as rGQDs(π)CoPc, NH2(π)CoPc, rGQDs@CoPc and NH2GQDs@CoPc. The resulting conjugates were adsorbed onto a glassy carbon electrode using the drop and dry method. The lowest limit of detection (LOD) was obtained for rGQDs(π)CoPc.
- Full Text:
- Date Issued: 2018
Electrospinning of carbon nanofibers for investigating the behaviour of lead electrodeposits on the carbon surface
- Authors: Madikane, Zipporah Kayakazi
- Date: 2018
- Subjects: Materials science , Nanotechnology Nanostructured materials
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/31622 , vital:31629
- Description: Over the years, the lead acid battery’s performance in modern vehicles has improved considerably to adapt to the new demands of vehicle electronics and start-stop applications. Although vehicles are valuable for commuting, their high volume of usage has resulted in an increase of fuel prices and emitted carbon dioxide (CO2). Due to the drastic global warming concerns, vehicle manufactures have been pressured into developing a variety of hybrid electric vehicles (HEV) that would reduce their fuel consumption and thereby reduced CO2 emission. The HEVs construction requires the implementation of advanced battery systems that operate under high rate partial state of charge (HRPSoC) conditions. During battery’s discharge, the Pb contained on the negative plate is oxidised to insulating PbSO4 crystals. When the battery is charged, the PbSO4 is reduced back to Pb. With prolonged use at HRPSoC, the battery undergoes an irreversible process wherein small PbSO4 crystallites dissolve and precipitate into large passivating PbSO4 crystals that accumulate as a dense layer on the surface of the negative plate. This layer restricts the diffusion of the H2SO4 electrolyte into the reaction sites for further reactions, resulting in the battery to fail prematurely. Research has shown that the inclusion of appropriate carbon materials on the negative active material (NAM) improves the performance of the batteries in HRPSoC cycling. This study looked at the making of some of the carbon-based additives by using relatively cheap materials such as polyvinyl alcohol (PVA) polymer with a sucrose blend in ratios of 75:25, 50:50 and 25:75, respectively. The blended materials were electrospun into PVA/Sucrose nanofibers. These were further stabilised by iodine and carbonised at 500 °C in a tube furnace. The properties of the carbon fibres were investigated by a number of analytical techniques such as TGA, DSC, XRD, BET, FTIR and SEM. The obtained carbon fibre surfaces were further electroplated with Pb in order to investigate the chemical bonding, the relationship between the carbon-based material interface and the Pb was investigated by SEM and CV techniques. The results of the study demonstrated that the varied ratios of the PVA/Sucrose nanofibers influenced the differences in their respective chemical and physical properties. Thermal analysis demonstrated that at approximately 500 °C, the final residue of the PVA/Sucrose nanofibers decreased as the sucrose content decreased. iii Carbonisation of the nanofibers was confirmed by the structural changes corresponding to the disappearance of the major bonds of PVA and sucrose materials, as well as by the appearance of C=C stretches. Carbonisation was also confirmed by the XRD diffractogram that demonstrated two broad amorphous peaks that corresponded to the planes of the graphite structure. The broadness of the peaks confirmed the amorphous nature of the carbon fibres. The morphological studies demonstrated that upon blending PVA with increasing quantities of sucrose, the uniformity of the fibres was altered into beaded fibrous structures with large diameters due to the increased viscosity of the electrospinning solution. The behaviour of the Pb deposits on the carbon surfaces was influenced by the high quantity of PVA present on the blend and the fibrous structure of the carbonised material. The Pb had high affinity towards the fibrous carbon derived from 75:25 as it deposited widely across the surface. Whereas, the absence of Pb deposits on the surface of the carbon derived from the 25:75 ratio was an indication that the high sucrose content and the bulky non-fibrous structure hindered the electrodeposition. The electrochemical study findings demonstrated that the bare Pb electrode had two distinct current peaks corresponding to the anodic (discharge) and cathodic (charge) reactions of Pb/PbSO4. Upon the inclusion of the electrospun carbon materials on the Pb electrode, the intensities of the anodic and cathodic peaks were reduced. Implying that none of the carbon materials enhanced the electrochemical redox reactions of the Pb/PbSO4 couple in the H2SO4 electrolyte.
- Full Text:
- Date Issued: 2018
- Authors: Madikane, Zipporah Kayakazi
- Date: 2018
- Subjects: Materials science , Nanotechnology Nanostructured materials
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/31622 , vital:31629
- Description: Over the years, the lead acid battery’s performance in modern vehicles has improved considerably to adapt to the new demands of vehicle electronics and start-stop applications. Although vehicles are valuable for commuting, their high volume of usage has resulted in an increase of fuel prices and emitted carbon dioxide (CO2). Due to the drastic global warming concerns, vehicle manufactures have been pressured into developing a variety of hybrid electric vehicles (HEV) that would reduce their fuel consumption and thereby reduced CO2 emission. The HEVs construction requires the implementation of advanced battery systems that operate under high rate partial state of charge (HRPSoC) conditions. During battery’s discharge, the Pb contained on the negative plate is oxidised to insulating PbSO4 crystals. When the battery is charged, the PbSO4 is reduced back to Pb. With prolonged use at HRPSoC, the battery undergoes an irreversible process wherein small PbSO4 crystallites dissolve and precipitate into large passivating PbSO4 crystals that accumulate as a dense layer on the surface of the negative plate. This layer restricts the diffusion of the H2SO4 electrolyte into the reaction sites for further reactions, resulting in the battery to fail prematurely. Research has shown that the inclusion of appropriate carbon materials on the negative active material (NAM) improves the performance of the batteries in HRPSoC cycling. This study looked at the making of some of the carbon-based additives by using relatively cheap materials such as polyvinyl alcohol (PVA) polymer with a sucrose blend in ratios of 75:25, 50:50 and 25:75, respectively. The blended materials were electrospun into PVA/Sucrose nanofibers. These were further stabilised by iodine and carbonised at 500 °C in a tube furnace. The properties of the carbon fibres were investigated by a number of analytical techniques such as TGA, DSC, XRD, BET, FTIR and SEM. The obtained carbon fibre surfaces were further electroplated with Pb in order to investigate the chemical bonding, the relationship between the carbon-based material interface and the Pb was investigated by SEM and CV techniques. The results of the study demonstrated that the varied ratios of the PVA/Sucrose nanofibers influenced the differences in their respective chemical and physical properties. Thermal analysis demonstrated that at approximately 500 °C, the final residue of the PVA/Sucrose nanofibers decreased as the sucrose content decreased. iii Carbonisation of the nanofibers was confirmed by the structural changes corresponding to the disappearance of the major bonds of PVA and sucrose materials, as well as by the appearance of C=C stretches. Carbonisation was also confirmed by the XRD diffractogram that demonstrated two broad amorphous peaks that corresponded to the planes of the graphite structure. The broadness of the peaks confirmed the amorphous nature of the carbon fibres. The morphological studies demonstrated that upon blending PVA with increasing quantities of sucrose, the uniformity of the fibres was altered into beaded fibrous structures with large diameters due to the increased viscosity of the electrospinning solution. The behaviour of the Pb deposits on the carbon surfaces was influenced by the high quantity of PVA present on the blend and the fibrous structure of the carbonised material. The Pb had high affinity towards the fibrous carbon derived from 75:25 as it deposited widely across the surface. Whereas, the absence of Pb deposits on the surface of the carbon derived from the 25:75 ratio was an indication that the high sucrose content and the bulky non-fibrous structure hindered the electrodeposition. The electrochemical study findings demonstrated that the bare Pb electrode had two distinct current peaks corresponding to the anodic (discharge) and cathodic (charge) reactions of Pb/PbSO4. Upon the inclusion of the electrospun carbon materials on the Pb electrode, the intensities of the anodic and cathodic peaks were reduced. Implying that none of the carbon materials enhanced the electrochemical redox reactions of the Pb/PbSO4 couple in the H2SO4 electrolyte.
- Full Text:
- Date Issued: 2018
Electrospun 3, 5-dithienylvinyleneBODIPY embedded polystyrene nanofibers for the photocatalytic degradation of azo dyes in industrial wastewaters
- Lebechi, Augustus K, Gai, Lizhi, Shen, Zhen, Nyokong, Tebello, Mack, John
- Authors: Lebechi, Augustus K , Gai, Lizhi , Shen, Zhen , Nyokong, Tebello , Mack, John
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187679 , vital:44686 , xlink:href="https://doi.org/10.1142/S1088424618500360"
- Description: The potential utility of electrospun polystyrene (PS) nanofibers embedded with 2,6-diiodo-8-phenyl-1,7-dimethyl-3,5-di-2-thienylvinyleneBODIPY for the photocatalytic degradation of azo dyes is investigated. A comparison of the singlet oxygen quantum yield of the ππ-extended BODIPY dye in solution and in the PS nanofibers demonstrates that its photosensitizer properties are retained when it is embedded in the solid phase. The photocatalytic degradation properties of the PS nanofibers for Methyl Orange and Orange G were determined by using a Thorlabs 625 nm light emitting diode. The rate of photodegradation increases with the Orange G and Methyl Orange concentration and follows pseudo-first order kinetics at pH 6.7.
- Full Text:
- Date Issued: 2018
- Authors: Lebechi, Augustus K , Gai, Lizhi , Shen, Zhen , Nyokong, Tebello , Mack, John
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187679 , vital:44686 , xlink:href="https://doi.org/10.1142/S1088424618500360"
- Description: The potential utility of electrospun polystyrene (PS) nanofibers embedded with 2,6-diiodo-8-phenyl-1,7-dimethyl-3,5-di-2-thienylvinyleneBODIPY for the photocatalytic degradation of azo dyes is investigated. A comparison of the singlet oxygen quantum yield of the ππ-extended BODIPY dye in solution and in the PS nanofibers demonstrates that its photosensitizer properties are retained when it is embedded in the solid phase. The photocatalytic degradation properties of the PS nanofibers for Methyl Orange and Orange G were determined by using a Thorlabs 625 nm light emitting diode. The rate of photodegradation increases with the Orange G and Methyl Orange concentration and follows pseudo-first order kinetics at pH 6.7.
- Full Text:
- Date Issued: 2018
Elevated CO2 determines cell damage and nitrogen allocation in barley subjected to aphid herbivory
- Authors: Gallagher, Sean
- Date: 2018
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/64337 , vital:28535
- Description: Expected release date-May 2019
- Full Text:
- Date Issued: 2018
- Authors: Gallagher, Sean
- Date: 2018
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/64337 , vital:28535
- Description: Expected release date-May 2019
- Full Text:
- Date Issued: 2018
Emplacement of inflated Pāhoehoe flows in the Naude’s Nek Pass, Lesotho remnant, Karoo continental flood basalt province: use of flow-lobe tumuli in understanding flood basalt emplacement
- Jay, Anne E, Marsh, Julian S, Fluteau, F, Courtillot, V
- Authors: Jay, Anne E , Marsh, Julian S , Fluteau, F , Courtillot, V
- Date: 2018
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/60752 , vital:27826 , https://link.springer.com/article/10.1007/s00445-017-1189-6
- Description: Physical volcanological features are presented for a 710-m-thick section, of the Naude’s Nek Pass, within the lower part of the Lesotho remnant of the Karoo Large Igneous Province. The section consists of inflated pāhoehoe lava with thin, impersistent sedimentary interbeds towards the base. There are seven discreet packages of compound and hummocky pāhoehoe lobes containing flow-lobe tumuli, making up approximately 50% of the section. Approximately 45% of the sequence consists of 14 sheet lobes, between 10 and 52-m-thick. The majority of the sheet lobes are in two packages indicating prolonged periods of lava supply capable of producing thick sheet lobes. The other sheet lobes are as individual lobes or pairs, within compound flows, suggesting brief increases in lava supply rate. We suggest, contrary to current belief, that there is no evidence that compound flows are proximal to source and sheet lobes (simple flows) are distal to source and we propose that the presence of flow-lobe tumuli in compound flows could be an indicator that a flow is distal to source. We use detailed, previously published, studies of the Thakurvadi Formation (Deccan Traps) as an example. We show that the length of a lobe and therefore the sections that are ‘medial or distal to source’ are specific to each individual lobe and are dependent on the lava supply of each eruptive event, and as such flow lobe tumuli can be used as an indicator of relative distance from source.
- Full Text:
- Date Issued: 2018
- Authors: Jay, Anne E , Marsh, Julian S , Fluteau, F , Courtillot, V
- Date: 2018
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/60752 , vital:27826 , https://link.springer.com/article/10.1007/s00445-017-1189-6
- Description: Physical volcanological features are presented for a 710-m-thick section, of the Naude’s Nek Pass, within the lower part of the Lesotho remnant of the Karoo Large Igneous Province. The section consists of inflated pāhoehoe lava with thin, impersistent sedimentary interbeds towards the base. There are seven discreet packages of compound and hummocky pāhoehoe lobes containing flow-lobe tumuli, making up approximately 50% of the section. Approximately 45% of the sequence consists of 14 sheet lobes, between 10 and 52-m-thick. The majority of the sheet lobes are in two packages indicating prolonged periods of lava supply capable of producing thick sheet lobes. The other sheet lobes are as individual lobes or pairs, within compound flows, suggesting brief increases in lava supply rate. We suggest, contrary to current belief, that there is no evidence that compound flows are proximal to source and sheet lobes (simple flows) are distal to source and we propose that the presence of flow-lobe tumuli in compound flows could be an indicator that a flow is distal to source. We use detailed, previously published, studies of the Thakurvadi Formation (Deccan Traps) as an example. We show that the length of a lobe and therefore the sections that are ‘medial or distal to source’ are specific to each individual lobe and are dependent on the lava supply of each eruptive event, and as such flow lobe tumuli can be used as an indicator of relative distance from source.
- Full Text:
- Date Issued: 2018
Employee motivation, workplace surveillance and employee engagement among selected Zimbabwe revenue authority employees
- Tsvangirai, Fidelis Pedzisai
- Authors: Tsvangirai, Fidelis Pedzisai
- Date: 2018
- Subjects: Employee motivation Employee motivation--Zimbabwe Organizational effectiveness--Zimbabwe
- Language: English
- Type: Thesis , Doctoral , Industrial Psychology
- Identifier: http://hdl.handle.net/10353/17384 , vital:40961
- Description: Orientation: The study is located in the micro environmental circumstances in Zimbabwe where the size of the informal sector is overtaking that of the formal sector. The country is experiencing a high labour turnover averaging at 19percent per year due to an unstable economic setting. The Zimbabwe Revenue Authority (ZIMRA) is experiencing an employee engagement score as low as 2.1 out of 5. This low employee engagement level and high labour turnover call for employers to find strategies not only to keep their employees motivated and engaged but also to monitor how they work. Research purpose: The study sought to examine how employee motivation mediates between workplace surveillance and employee engagement among selected employees at the Zimbabwe Revenue Authority (ZIMRA). Motivation of the study: Public organisations often face the criticism that they do not deliver the quality of service expected and one in every five of their employees is disengaged from their work. ZIMRA’s mandate has a significant impact on the country’s gross domestic product (GDP) and the organisation needs to deliver against all odds. Currently no research exists which provides information on the mediating effect of employee motivation on the relationship between workplace surveillance and employee engagement in Zimbabwe. Research philosophy, design and method: This study adopted the positivism research philosophy and a survey research design, which is quantitative and descriptive in nature. The study utilised the principles of structural equation modelling (SEM) in formulating the research hypotheses and in data analysis. Main findings: The findings of the study, through utilising SEM, were that a negative relationship exists between workplace surveillance and employee engagement and that employee motivation has a positive significant relationship with employee engagement. The study also found that workplace surveillance positively relates to employee motivation. The study also found that employee motivation partially mediates the relationship between workplace surveillance and employee engagement. Practical/Managerial implications: A negative relationship between workplace surveillance and employee engagement calls for ZIMRA management to seek employee buy-in when implementing workplace surveillance measures. A positive relationship between employee motivation and employee engagement calls for ZIMRA management to invest much in these two variables. A positive relationship between workplace surveillance and employee motivation calls for ZIMRA management to put in place policies that ensure employees do not abuse work time by doing their own business. Contribution or value-add: The study contributes to the body of knowledge on the debate around the impact of employee motivation as a mediator of the relationship between workplace surveillance and employee engagement. This study agree with the vast amount of literature that the relationship between workplace surveillance and employee motivation is not always negative.
- Full Text:
- Date Issued: 2018
- Authors: Tsvangirai, Fidelis Pedzisai
- Date: 2018
- Subjects: Employee motivation Employee motivation--Zimbabwe Organizational effectiveness--Zimbabwe
- Language: English
- Type: Thesis , Doctoral , Industrial Psychology
- Identifier: http://hdl.handle.net/10353/17384 , vital:40961
- Description: Orientation: The study is located in the micro environmental circumstances in Zimbabwe where the size of the informal sector is overtaking that of the formal sector. The country is experiencing a high labour turnover averaging at 19percent per year due to an unstable economic setting. The Zimbabwe Revenue Authority (ZIMRA) is experiencing an employee engagement score as low as 2.1 out of 5. This low employee engagement level and high labour turnover call for employers to find strategies not only to keep their employees motivated and engaged but also to monitor how they work. Research purpose: The study sought to examine how employee motivation mediates between workplace surveillance and employee engagement among selected employees at the Zimbabwe Revenue Authority (ZIMRA). Motivation of the study: Public organisations often face the criticism that they do not deliver the quality of service expected and one in every five of their employees is disengaged from their work. ZIMRA’s mandate has a significant impact on the country’s gross domestic product (GDP) and the organisation needs to deliver against all odds. Currently no research exists which provides information on the mediating effect of employee motivation on the relationship between workplace surveillance and employee engagement in Zimbabwe. Research philosophy, design and method: This study adopted the positivism research philosophy and a survey research design, which is quantitative and descriptive in nature. The study utilised the principles of structural equation modelling (SEM) in formulating the research hypotheses and in data analysis. Main findings: The findings of the study, through utilising SEM, were that a negative relationship exists between workplace surveillance and employee engagement and that employee motivation has a positive significant relationship with employee engagement. The study also found that workplace surveillance positively relates to employee motivation. The study also found that employee motivation partially mediates the relationship between workplace surveillance and employee engagement. Practical/Managerial implications: A negative relationship between workplace surveillance and employee engagement calls for ZIMRA management to seek employee buy-in when implementing workplace surveillance measures. A positive relationship between employee motivation and employee engagement calls for ZIMRA management to invest much in these two variables. A positive relationship between workplace surveillance and employee motivation calls for ZIMRA management to put in place policies that ensure employees do not abuse work time by doing their own business. Contribution or value-add: The study contributes to the body of knowledge on the debate around the impact of employee motivation as a mediator of the relationship between workplace surveillance and employee engagement. This study agree with the vast amount of literature that the relationship between workplace surveillance and employee motivation is not always negative.
- Full Text:
- Date Issued: 2018
Employee pension and provident fund rights
- Authors: Richard, Makhado Fhatuwani
- Date: 2018
- Subjects: Pension funds -- Law and legislation -- South Africa , Pension trusts -- South Africa Pensions -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: http://hdl.handle.net/10948/35156 , vital:33642
- Description: Ideally, every employee is required to retire at some stage in life. Some retire at a relatively early age, whilst others work for as long as is possible. The generally accepted retirement ages are 55, 60 or 65, but vary from company to company as stipulated in the specific company's provident or pension fund rules or policy. Once retired, an individual would rely on social insurance as a source of income in the form of pension or a provident fund. Social insurance, in this regard, refers to the earned benefits of employees and is often linked to formal employment. South Africa, as a middle-income developing country, has incorporated such elements into its social security system. The main aim of a pension or provident fund is to provide benefits for its members when they retire from employment, retrenched, unable to work due to illness and for family in the case a member dies while still working. These forms of social security are key to people’s survival and are referred to as safety nets. benefits. Participation on a voluntary basis by the self-employed is allowed but the take-up has been low Employees’ pension and provident rights under a pension or provident scheme do not arise only under the trusts of the scheme but also as contractual terms of the employment relationship between the employer and its employees. This often takes effect on the date of taking up employment, or on entering into an agreement with the employer. Employment law covers all rights and obligations within the employee employer relationship and covers a range of legal issues such as discrimination, wrongful termination, wages and taxation. Many of these issues are governed by the applicable law. Although the South African retirement fund system is in many respects financially sound and well regulated, several individuals still reach their retirement age with inadequate savings. This occurs for several reasons. For many people, during their working life, the build-up of savings is disrupted, or the costs associated with retirement fund provisioning are relatively high. This problem is not only grave for some workers in the formal sector, but largely for those in the rapidly increasing informal sector. Majority of people still lack effective access to an affordable retirement funding vehicle, for the most part, are completely excluded from social protection schemes, social insurance schemes. The South African retirement fund industry has been heavily influenced by a racially divided past and the parallel existence of developed and emerging components of the economy. In the past, racially discriminatory exclusion from the pension fund or provident fund membership was prevalent. In many cases it was indirect discrimination based on job categorisation, such as the distinction between weekly paid and monthly paid staff. Where the staff complement was racially stratified, people were excluded from membership on the grounds of race. Discrimination in the workplace can deny individuals opportunities and thereby deprive society of what those individuals can and could contribute. This has unfortunately been the case in South Africa’s history, the administration of pension and provident funds being one of many examples.
- Full Text:
- Date Issued: 2018
- Authors: Richard, Makhado Fhatuwani
- Date: 2018
- Subjects: Pension funds -- Law and legislation -- South Africa , Pension trusts -- South Africa Pensions -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: http://hdl.handle.net/10948/35156 , vital:33642
- Description: Ideally, every employee is required to retire at some stage in life. Some retire at a relatively early age, whilst others work for as long as is possible. The generally accepted retirement ages are 55, 60 or 65, but vary from company to company as stipulated in the specific company's provident or pension fund rules or policy. Once retired, an individual would rely on social insurance as a source of income in the form of pension or a provident fund. Social insurance, in this regard, refers to the earned benefits of employees and is often linked to formal employment. South Africa, as a middle-income developing country, has incorporated such elements into its social security system. The main aim of a pension or provident fund is to provide benefits for its members when they retire from employment, retrenched, unable to work due to illness and for family in the case a member dies while still working. These forms of social security are key to people’s survival and are referred to as safety nets. benefits. Participation on a voluntary basis by the self-employed is allowed but the take-up has been low Employees’ pension and provident rights under a pension or provident scheme do not arise only under the trusts of the scheme but also as contractual terms of the employment relationship between the employer and its employees. This often takes effect on the date of taking up employment, or on entering into an agreement with the employer. Employment law covers all rights and obligations within the employee employer relationship and covers a range of legal issues such as discrimination, wrongful termination, wages and taxation. Many of these issues are governed by the applicable law. Although the South African retirement fund system is in many respects financially sound and well regulated, several individuals still reach their retirement age with inadequate savings. This occurs for several reasons. For many people, during their working life, the build-up of savings is disrupted, or the costs associated with retirement fund provisioning are relatively high. This problem is not only grave for some workers in the formal sector, but largely for those in the rapidly increasing informal sector. Majority of people still lack effective access to an affordable retirement funding vehicle, for the most part, are completely excluded from social protection schemes, social insurance schemes. The South African retirement fund industry has been heavily influenced by a racially divided past and the parallel existence of developed and emerging components of the economy. In the past, racially discriminatory exclusion from the pension fund or provident fund membership was prevalent. In many cases it was indirect discrimination based on job categorisation, such as the distinction between weekly paid and monthly paid staff. Where the staff complement was racially stratified, people were excluded from membership on the grounds of race. Discrimination in the workplace can deny individuals opportunities and thereby deprive society of what those individuals can and could contribute. This has unfortunately been the case in South Africa’s history, the administration of pension and provident funds being one of many examples.
- Full Text:
- Date Issued: 2018
Energy maximisation strategies of different African herbivores in a fire dominated and nutrient poor grassland ecosystem
- Authors: Brooke, Christopher
- Date: 2018
- Subjects: Grassland ecology -- South Africa -- Eastern Cape , Animals -- Food -- South Africa -- Eastern Cape , Herbivores -- Ecology -- South Africa -- Eastern Cape , Fire ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/21961 , vital:29807
- Description: Fire and herbivory are both major drivers in grassland ecosystems throughout the world. Although these two driving forces act independently from one another the relationship between fire and herbivory may be more significant than either acting on their own. Heterogeneity within the landscape as a result of fire results in herbivores having to adapt their behaviour in space and time. My research focussed on 1) characterising the fire regime on Mkambati Nature Reserve (hereafter Mkambati) and 2) determining the foraging choices and energy maximisation principles displayed by herbivores in relation to the biomass of vegetation and post fire vegetation age. Fire regimes were characterised between 2007-2016 in the low nutrient coastal grasslands of Mkambati in terms of fire season, seasonality of fire-prone weather conditions, fire return interval (FRI) and influence of poaching-related ignitions. Based on these results I then assessed foraging choices in terms of energy maximisation of four large herbivore species. I explored what energy maximisation strategy was employed, i.e. maximisation of daily digestible energy (DDE) (recently burnt low biomass vegetation) or instantaneous digestible energy (IDE) (older high biomass vegetation), by herbivore species with different morpho-physiological traits. Common reedbuck (Redunca arundinum), red hartebeest (Alcelaphus buselaphus subsp. caama), zebra (Equus quagga) and eland (Tragelaphus oryx subsp. oryx) were fitted with GPS satellite tracking collars, and hourly GPS locations (observed) were taken between 2008 and 2016. Using mixed effects models, I compared observed and an associated set of random locations to determine the energy maximisation strategy employed by each species. Our results indicated that fires were concentrated in winter when monthly fire danger weather (FDI) was highest. The mean FRI at Mkambati was <3 years, but varied according to vegetation type, and whether censoring (for open ended FRIs) was applied to estimate mean FRIs. Poachers, with the intention of attracting ungulates, are an important source of ignition at Mkambati. Accordingly FRIs were shorter (approximately 2 years) in areas within 3 km of likely poacher entry points. Although all fires recorded at Mkambati during the study period were of anthropogenic origin, mean FRI still fell within the natural range reported for interior grasslands in South Africa. Based on these findings, underpinned by the fire regime information, I showed that red hartebeest and zebra maximised DDE inside and outside of fire seasons and frequently foraged in low biomass recently burnt grasslands. Eland generally favoured areas where they could maximise IDE outside of the fire season, however during the fire season they switched strategy to maximise DDE. Reedbuck did not maximise IDE or DDE at the same scale (patch scale) as the other species, but at a landscape (broader) scale they maximised both IDE and DDE. Through this research I have shown how regular fire affects the foraging and energy maximisation behaviour of large African herbivores and how morpho-physiological traits affect these decisions. In response to these results I recommend that the management of Mkambati implement a focused monitoring program comparing the frequently and less frequently burnt areas of the reserve in order to understand the complex effects of anthropogenic fire and its subsequent effects on the biota of Mkambati.
- Full Text:
- Date Issued: 2018
- Authors: Brooke, Christopher
- Date: 2018
- Subjects: Grassland ecology -- South Africa -- Eastern Cape , Animals -- Food -- South Africa -- Eastern Cape , Herbivores -- Ecology -- South Africa -- Eastern Cape , Fire ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/21961 , vital:29807
- Description: Fire and herbivory are both major drivers in grassland ecosystems throughout the world. Although these two driving forces act independently from one another the relationship between fire and herbivory may be more significant than either acting on their own. Heterogeneity within the landscape as a result of fire results in herbivores having to adapt their behaviour in space and time. My research focussed on 1) characterising the fire regime on Mkambati Nature Reserve (hereafter Mkambati) and 2) determining the foraging choices and energy maximisation principles displayed by herbivores in relation to the biomass of vegetation and post fire vegetation age. Fire regimes were characterised between 2007-2016 in the low nutrient coastal grasslands of Mkambati in terms of fire season, seasonality of fire-prone weather conditions, fire return interval (FRI) and influence of poaching-related ignitions. Based on these results I then assessed foraging choices in terms of energy maximisation of four large herbivore species. I explored what energy maximisation strategy was employed, i.e. maximisation of daily digestible energy (DDE) (recently burnt low biomass vegetation) or instantaneous digestible energy (IDE) (older high biomass vegetation), by herbivore species with different morpho-physiological traits. Common reedbuck (Redunca arundinum), red hartebeest (Alcelaphus buselaphus subsp. caama), zebra (Equus quagga) and eland (Tragelaphus oryx subsp. oryx) were fitted with GPS satellite tracking collars, and hourly GPS locations (observed) were taken between 2008 and 2016. Using mixed effects models, I compared observed and an associated set of random locations to determine the energy maximisation strategy employed by each species. Our results indicated that fires were concentrated in winter when monthly fire danger weather (FDI) was highest. The mean FRI at Mkambati was <3 years, but varied according to vegetation type, and whether censoring (for open ended FRIs) was applied to estimate mean FRIs. Poachers, with the intention of attracting ungulates, are an important source of ignition at Mkambati. Accordingly FRIs were shorter (approximately 2 years) in areas within 3 km of likely poacher entry points. Although all fires recorded at Mkambati during the study period were of anthropogenic origin, mean FRI still fell within the natural range reported for interior grasslands in South Africa. Based on these findings, underpinned by the fire regime information, I showed that red hartebeest and zebra maximised DDE inside and outside of fire seasons and frequently foraged in low biomass recently burnt grasslands. Eland generally favoured areas where they could maximise IDE outside of the fire season, however during the fire season they switched strategy to maximise DDE. Reedbuck did not maximise IDE or DDE at the same scale (patch scale) as the other species, but at a landscape (broader) scale they maximised both IDE and DDE. Through this research I have shown how regular fire affects the foraging and energy maximisation behaviour of large African herbivores and how morpho-physiological traits affect these decisions. In response to these results I recommend that the management of Mkambati implement a focused monitoring program comparing the frequently and less frequently burnt areas of the reserve in order to understand the complex effects of anthropogenic fire and its subsequent effects on the biota of Mkambati.
- Full Text:
- Date Issued: 2018
Energy use patterns and trends: the impact of energy policy in South African low-income households
- Israel-Akinbo, Sylvia Olawumi
- Authors: Israel-Akinbo, Sylvia Olawumi
- Date: 2018
- Subjects: Energy policy -- Social aspects -- South Africa , Energy security -- South Africa , Households -- Economic aspects -- South Africa , Poor -- Energy assistance -- South Africa , Poor -- South Africa , University of Cape Town. National Income Dynamics Study , Free Basic Electricity Policy (South Africa) , Income and Expenditure Survey (South Africa)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62264 , vital:28148
- Description: Energy poverty is a growing concern especially amongst low-income populations in developing countries. The transition to modern energy carriers is associated with welfare improvement and it is considered as an important developmental goal to achieve, in order to eradicate energy poverty. As such, the South African government has made energy poverty an issue of policy focus. Literature abounds with different measures of energy poverty; energy programmes and policies are also aimed at improving the welfare of the low-income households in terms of basic services such as electricity. As a point of entry into this study, this thesis explored energy use patterns and trends in low-income South African households. The research objectives addressed in the study included investigating the extent of energy poverty through a multidimensional energy poverty index, examining the extent to which the 'energy ladder' and 'energy stacking' models explains energy transition patterns and to examining whether the Free Basic Electricity Policy has impacted on energy choices and energy poverty. In order to contribute to energy poverty and energy policy discussion in South Africa, this study has investigated the dimensions of energy poverty amongst low-income South African households from these three different perspectives (objectives). A positivist approach, by using a quantitative method was used to underpin the study. The study utilised secondary data, which were from the National Income Dynamics Survey and Income and Expenditure Survey. The former was used for the analysis of the multidimensional energy poverty index and energy transition patterns whilst the latter was used for the analysis of the impact of the Free Basic Electricity Policy. The four waves of the National Income Dynamics Survey, with 2008 as the base year and the 2010/2011 version of the Income and Expenditure Survey were used whilst the data were processed through the quantitative software package, STATA version 12. The data were then analysed using the multidimensional energy poverty framework by Nussbaumer et al. (2011) and econometric models, which best fit the objectives. The result of the panel analysis, which assesses the multidimensional energy poverty for low-income households in South Africa showed that low-income households in both urban and rural areas are in a moderate state of energy poverty but different levels. However, the cross-sectional analysis revealed that the percentage of low-income households that are energy poor is reducing for the rural households but increasing for their urban counterparts from 2008 to 2014. The panel and cross-sectional results of the contribution of the energy dimensions in multidimensional energy poverty shows that the low-income households are especially energy poor in terms of heating fuel. The findings from the econometric estimates partly confirmed an energy ladder behaviour for the energy choice for cooking. An energy stacking behaviour was confirmed for the low- income households for these energy services - heating and lighting. Moreover, it was found that with respect to cooking and heating, low-income households living in a modern dwelling, having a small household size and residing in an urban area are less likely to use transitional or traditional energy carriers but most likely to use modern energy carriers. In addition, low-income households are more likely to use modern energy carriers for their cooking and heating in 2010, 2012 and 2014 than in 2008. For lighting energy service, low- income households living in a modern dwelling in an urban settlement are most likely to use modern energy carriers for lighting and less likely to use transitional energy carriers or candles. Only in 2014 were low-income households more likely to use modern energy carriers for lighting than in 2008. The results further showed that modern energy carriers have the highest probability of being preferred for lighting followed by cooking and lastly heating. Also emerging from the findings are that more urban low-income households are receiving the Free Basic Electricity (FBE) grant than their counterparts in the rural areas. The probability of low-income households owning entertainment/education appliance and food preserving appliance is positively influenced by access to Free Basic Electricity. The low- income households living in an urban settlement and in a modern type of dwelling supported this result. However, household size does not seems to support this result should it grow larger.
- Full Text:
- Date Issued: 2018
- Authors: Israel-Akinbo, Sylvia Olawumi
- Date: 2018
- Subjects: Energy policy -- Social aspects -- South Africa , Energy security -- South Africa , Households -- Economic aspects -- South Africa , Poor -- Energy assistance -- South Africa , Poor -- South Africa , University of Cape Town. National Income Dynamics Study , Free Basic Electricity Policy (South Africa) , Income and Expenditure Survey (South Africa)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62264 , vital:28148
- Description: Energy poverty is a growing concern especially amongst low-income populations in developing countries. The transition to modern energy carriers is associated with welfare improvement and it is considered as an important developmental goal to achieve, in order to eradicate energy poverty. As such, the South African government has made energy poverty an issue of policy focus. Literature abounds with different measures of energy poverty; energy programmes and policies are also aimed at improving the welfare of the low-income households in terms of basic services such as electricity. As a point of entry into this study, this thesis explored energy use patterns and trends in low-income South African households. The research objectives addressed in the study included investigating the extent of energy poverty through a multidimensional energy poverty index, examining the extent to which the 'energy ladder' and 'energy stacking' models explains energy transition patterns and to examining whether the Free Basic Electricity Policy has impacted on energy choices and energy poverty. In order to contribute to energy poverty and energy policy discussion in South Africa, this study has investigated the dimensions of energy poverty amongst low-income South African households from these three different perspectives (objectives). A positivist approach, by using a quantitative method was used to underpin the study. The study utilised secondary data, which were from the National Income Dynamics Survey and Income and Expenditure Survey. The former was used for the analysis of the multidimensional energy poverty index and energy transition patterns whilst the latter was used for the analysis of the impact of the Free Basic Electricity Policy. The four waves of the National Income Dynamics Survey, with 2008 as the base year and the 2010/2011 version of the Income and Expenditure Survey were used whilst the data were processed through the quantitative software package, STATA version 12. The data were then analysed using the multidimensional energy poverty framework by Nussbaumer et al. (2011) and econometric models, which best fit the objectives. The result of the panel analysis, which assesses the multidimensional energy poverty for low-income households in South Africa showed that low-income households in both urban and rural areas are in a moderate state of energy poverty but different levels. However, the cross-sectional analysis revealed that the percentage of low-income households that are energy poor is reducing for the rural households but increasing for their urban counterparts from 2008 to 2014. The panel and cross-sectional results of the contribution of the energy dimensions in multidimensional energy poverty shows that the low-income households are especially energy poor in terms of heating fuel. The findings from the econometric estimates partly confirmed an energy ladder behaviour for the energy choice for cooking. An energy stacking behaviour was confirmed for the low- income households for these energy services - heating and lighting. Moreover, it was found that with respect to cooking and heating, low-income households living in a modern dwelling, having a small household size and residing in an urban area are less likely to use transitional or traditional energy carriers but most likely to use modern energy carriers. In addition, low-income households are more likely to use modern energy carriers for their cooking and heating in 2010, 2012 and 2014 than in 2008. For lighting energy service, low- income households living in a modern dwelling in an urban settlement are most likely to use modern energy carriers for lighting and less likely to use transitional energy carriers or candles. Only in 2014 were low-income households more likely to use modern energy carriers for lighting than in 2008. The results further showed that modern energy carriers have the highest probability of being preferred for lighting followed by cooking and lastly heating. Also emerging from the findings are that more urban low-income households are receiving the Free Basic Electricity (FBE) grant than their counterparts in the rural areas. The probability of low-income households owning entertainment/education appliance and food preserving appliance is positively influenced by access to Free Basic Electricity. The low- income households living in an urban settlement and in a modern type of dwelling supported this result. However, household size does not seems to support this result should it grow larger.
- Full Text:
- Date Issued: 2018
Engagement of fathers in early childhood care and education provisioning in one education district in the Eastern Cape Province, South Africa
- Authors: Mufutau, Monsuru Atanda
- Date: 2018
- Subjects: Early childhood education -- South Africa -- Eastern Cape Education -- Parent participation Early childhood education -- Parent participation
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/8942 , vital:34175
- Description: This study focused on the engagement of fathers in early childhood care and education provisioning in one education district in the Eastern Cape Province, South Africa. Significantly, a specific programme to get fathers engaged in the early childhood of their children is not well addressed by the National Integrated Early Childhood Development (ECD) Policy of 2015, despite the notion that early childhood education provisioning demands the total involvement of multiple partners and other stakeholders. The research drew its theoretical framework from the ecological system theory. Ecological system theory argues that, in order to understand human development, one must consider the entire ecological system in which growth occurs. This study utilized the quantitative research approach to obtain primary data in line with the positivist paradigm. Data were analysed using descriptive and inferential statistics. The instruments were scrutinized by the research supervisor to ensure validity and were pre-tested in the field study. The reliability was obtained at a Cronbach’s alpha coefficient, of 0.94 and 0.96. The results were presented in the form of pie chart and grouped into different tables of sixteen. Pearson’s ProductMoment Correlation, Analysis of Variance and t-test were used to test the hypotheses at 0.05 level of significance. Two structured questionnaire instruments were used in the study, Principal and Teachers’ Views Questionnaire (PTVQ) and Father’s and Mother’s Views Questionnaire (FMVQ). The Multi-stage sampling technique was used to select the sample for this study. To this end, 16 principals, 12 teachers, 18 mothers and 18 fathers of children in the selected sample served as respondents. The results reveal that stakeholders have positive views about fathers’ engagement in early childhood care and education provisioning. The result indicated that schools do provide support mechanisms to encourage fathers’ engagement in early childhood care and education provisioning. The results showed that a number of strategies are used by the schools. The result also indicated that functional policy and practice will no doubt improve and encourage the engagement of fathers in ECCE provisioning. Furthermore, the study concluded that stakeholders have positive views on the engagement of fathers in ECCE provisioning. The study recommends that all stakeholders and media houses should be involved in the effective dissemination of information, and that the South African government should advocate for ECCE policies that lay out concrete commitment and guidelines for fathers and, above all, symposia, lectures, workshops, and seminars should be organized for fathers.
- Full Text:
- Date Issued: 2018
- Authors: Mufutau, Monsuru Atanda
- Date: 2018
- Subjects: Early childhood education -- South Africa -- Eastern Cape Education -- Parent participation Early childhood education -- Parent participation
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/8942 , vital:34175
- Description: This study focused on the engagement of fathers in early childhood care and education provisioning in one education district in the Eastern Cape Province, South Africa. Significantly, a specific programme to get fathers engaged in the early childhood of their children is not well addressed by the National Integrated Early Childhood Development (ECD) Policy of 2015, despite the notion that early childhood education provisioning demands the total involvement of multiple partners and other stakeholders. The research drew its theoretical framework from the ecological system theory. Ecological system theory argues that, in order to understand human development, one must consider the entire ecological system in which growth occurs. This study utilized the quantitative research approach to obtain primary data in line with the positivist paradigm. Data were analysed using descriptive and inferential statistics. The instruments were scrutinized by the research supervisor to ensure validity and were pre-tested in the field study. The reliability was obtained at a Cronbach’s alpha coefficient, of 0.94 and 0.96. The results were presented in the form of pie chart and grouped into different tables of sixteen. Pearson’s ProductMoment Correlation, Analysis of Variance and t-test were used to test the hypotheses at 0.05 level of significance. Two structured questionnaire instruments were used in the study, Principal and Teachers’ Views Questionnaire (PTVQ) and Father’s and Mother’s Views Questionnaire (FMVQ). The Multi-stage sampling technique was used to select the sample for this study. To this end, 16 principals, 12 teachers, 18 mothers and 18 fathers of children in the selected sample served as respondents. The results reveal that stakeholders have positive views about fathers’ engagement in early childhood care and education provisioning. The result indicated that schools do provide support mechanisms to encourage fathers’ engagement in early childhood care and education provisioning. The results showed that a number of strategies are used by the schools. The result also indicated that functional policy and practice will no doubt improve and encourage the engagement of fathers in ECCE provisioning. Furthermore, the study concluded that stakeholders have positive views on the engagement of fathers in ECCE provisioning. The study recommends that all stakeholders and media houses should be involved in the effective dissemination of information, and that the South African government should advocate for ECCE policies that lay out concrete commitment and guidelines for fathers and, above all, symposia, lectures, workshops, and seminars should be organized for fathers.
- Full Text:
- Date Issued: 2018
Engaging with media as a knowledge resource for making sense of climate change: a case study of the farmers of Nyanga, Zimbabwe
- Authors: Mandikonza, Blessing
- Date: 2018
- Subjects: Climatic changes in mass media , Knowledge, Sociology of , Farms, Small -- Zimbabwe -- Nyanga , Crops and climate -- Zimbabwe -- Nyanga , Agriculture -- Economic aspects -- Zimbabwe , Agriculture -- Environmental aspects -- Zimbabwe -- Nyanga , Agriculture and politics -- Zimbabwe -- Nyanga , Agriculture -- Research -- Sociological aspects , Agricultural journalism -- Zimbabwe , Land reform -- Zimbabwe -- Nyanga
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/63764 , vital:28486
- Description: This study explores how small-scale farmers in Nyanga, Zimbabwe engage with the media as a knowledge resource for achieving agricultural productivity, particularly in context of climate change. The study is contextualised by means of a literature review that maps out the history of agricultural productivity in Zimbabwe. It is argued that this history has been shaped by changes in both socio-economic context and climatic conditions. Both kinds of change impact on the degree to which small-scale farmers have access to knowledge that is of relevance to agricultural productivity. The study then examines the Zimbabwean media landscape, focusing on how history has shaped the way in which different media define their social purpose. This examination draws on Hallin and Mancini‟s „models‟ of media systems as well as Christian et al‟s traditions of media practice. It is concluded that, due to the high level of conflict that has characterised Zimbabwean history, aspects of both the polarised pluralist and democratic corporatist models are present in its media landscape. The collaborative, monitorial and radical approaches to media also exist in contestation with each other. Indeed, the media is characterised by profound contestation around the conceptualisation of social purpose. Furthermore, international media is of particular significance as a resource of knowledge within the local media landscape. The empirical component of the study explores the implications for the extent to which media are likely to serve as valuable knowledge resources for small-scale farmers. This exploration is pursued by means of a case study of the experiences of three farmers in Nyanga who were granted farms as part of the government‟s land-reform programme. In context of episodic biographical interviews, the participants share their experience of becoming farmers and of managing their farms. Attention is paid to the challenges they face with regards to producing successful crops, both in context of socio-economic and climatic conditions. The study looks at the way in which participants draw on the media as a knowledge resource to help them overcome these challenges. The participants understand international media to be a more credible knowledge resource, but also refer to the need for local media which can provides them with knowledge of local relevance. In this context they identify an absence of collaborative, developmental media that engages with the unique challenges that they face in producing crops. It is concluded that the value of media for the farmers of Nyanga as a knowledge resource for making sense of climate change would only be achieved through the establishment of locally produced, participatory media that foregrounds the use of indigenous language.
- Full Text:
- Date Issued: 2018
- Authors: Mandikonza, Blessing
- Date: 2018
- Subjects: Climatic changes in mass media , Knowledge, Sociology of , Farms, Small -- Zimbabwe -- Nyanga , Crops and climate -- Zimbabwe -- Nyanga , Agriculture -- Economic aspects -- Zimbabwe , Agriculture -- Environmental aspects -- Zimbabwe -- Nyanga , Agriculture and politics -- Zimbabwe -- Nyanga , Agriculture -- Research -- Sociological aspects , Agricultural journalism -- Zimbabwe , Land reform -- Zimbabwe -- Nyanga
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/63764 , vital:28486
- Description: This study explores how small-scale farmers in Nyanga, Zimbabwe engage with the media as a knowledge resource for achieving agricultural productivity, particularly in context of climate change. The study is contextualised by means of a literature review that maps out the history of agricultural productivity in Zimbabwe. It is argued that this history has been shaped by changes in both socio-economic context and climatic conditions. Both kinds of change impact on the degree to which small-scale farmers have access to knowledge that is of relevance to agricultural productivity. The study then examines the Zimbabwean media landscape, focusing on how history has shaped the way in which different media define their social purpose. This examination draws on Hallin and Mancini‟s „models‟ of media systems as well as Christian et al‟s traditions of media practice. It is concluded that, due to the high level of conflict that has characterised Zimbabwean history, aspects of both the polarised pluralist and democratic corporatist models are present in its media landscape. The collaborative, monitorial and radical approaches to media also exist in contestation with each other. Indeed, the media is characterised by profound contestation around the conceptualisation of social purpose. Furthermore, international media is of particular significance as a resource of knowledge within the local media landscape. The empirical component of the study explores the implications for the extent to which media are likely to serve as valuable knowledge resources for small-scale farmers. This exploration is pursued by means of a case study of the experiences of three farmers in Nyanga who were granted farms as part of the government‟s land-reform programme. In context of episodic biographical interviews, the participants share their experience of becoming farmers and of managing their farms. Attention is paid to the challenges they face with regards to producing successful crops, both in context of socio-economic and climatic conditions. The study looks at the way in which participants draw on the media as a knowledge resource to help them overcome these challenges. The participants understand international media to be a more credible knowledge resource, but also refer to the need for local media which can provides them with knowledge of local relevance. In this context they identify an absence of collaborative, developmental media that engages with the unique challenges that they face in producing crops. It is concluded that the value of media for the farmers of Nyanga as a knowledge resource for making sense of climate change would only be achieved through the establishment of locally produced, participatory media that foregrounds the use of indigenous language.
- Full Text:
- Date Issued: 2018
Enhanced nonlinear optical response of benzothiazole substituted ball-type phthalocyanines in the presence of metallic nanoparticles
- Nwaji, Njemuwa, Mack, John, Nyokong, Tebello
- Authors: Nwaji, Njemuwa , Mack, John , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188149 , vital:44727 , xlink:href="https://doi.org/10.1016/j.optmat.2018.05.052"
- Description: The synthesis of zinc-zinc, gallium-gallium and indium-indium ball-type phthalocyanines (complexes 4, 5 and 6) and the surface assembly of the complexes onto metallic gold and silver nanoparticles are reported in this work. Furthermore, their photophysical and nonlinear optical dynamics were investigated. Decreases in the fluorescence quantum yields with a corresponding increase in the triplet quantum yields of the nanoconjugates in comparison to complexes 4, 5 and 6 alone were observed. The mechanism of strong reverse saturable absorption observed was found to be predominantly dependent on excited state absorption. The optical limiting thresholds range from 0.09 to 0.19 J/cm2. Enhanced triplet parameters and nonlinear optical responses were found when the complexes were conjugated to metallic nanoparticles.
- Full Text:
- Date Issued: 2018
- Authors: Nwaji, Njemuwa , Mack, John , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188149 , vital:44727 , xlink:href="https://doi.org/10.1016/j.optmat.2018.05.052"
- Description: The synthesis of zinc-zinc, gallium-gallium and indium-indium ball-type phthalocyanines (complexes 4, 5 and 6) and the surface assembly of the complexes onto metallic gold and silver nanoparticles are reported in this work. Furthermore, their photophysical and nonlinear optical dynamics were investigated. Decreases in the fluorescence quantum yields with a corresponding increase in the triplet quantum yields of the nanoconjugates in comparison to complexes 4, 5 and 6 alone were observed. The mechanism of strong reverse saturable absorption observed was found to be predominantly dependent on excited state absorption. The optical limiting thresholds range from 0.09 to 0.19 J/cm2. Enhanced triplet parameters and nonlinear optical responses were found when the complexes were conjugated to metallic nanoparticles.
- Full Text:
- Date Issued: 2018
Enhancing employee engagement within exponential organisations
- Authors: Stander, Rizel
- Date: 2018
- Subjects: Employee motivation , Employees -- Attitudes Organizational change Reengineering (Management)
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/35278 , vital:33690
- Description: Mayo (2016, p. 88) states that many researchers agree that investing in employee engagement has guaranteed great returns; the question for organisations are whether these returns will be linear or exponential for them. A new breed of company emerged called the “exponential organisation” which leverage accelerating technologies to achieve an unheard-of business model that shows exponential growth. However, this technology is still created, maintained and reinvented by employees. Therefore, the premise is that highly engaged employees are one of the key factors that fuel exponential organisations, and this was under investigation in this research study. Employee engagement has been extensively researched yet only a few organisations can claim the majority of their employees are highly engaged. The topic of employee engagement within exponential organisations, however, has barely been covered by scholars or practitioners. Subsequently, given that it is a new organisational phenomenon, little academic or practitioner’s research could be found. For this reason, the main purpose of this study was to find key drivers of employee engagement within exponential organisations to develop a theoretical framework and hypotheses which could be statistically tested. The outcomes could assist in enhancing employee engagement within exponential organisations, thereby achieving greater business success. An online survey questionnaire was used to gather empirical data within a financial technology exponential organisation. The sample consisted of 40 fulltime employees working in Australia, China and South Africa of which most were between the ages of 35 to 44 years old and have been with the organisation for less than two years. The results showed that organisational management and employee autonomy were found to have a direct positive relationship with the concept of employee engagement and is found to be key drivers of employee engagement within exponential organisations.
- Full Text:
- Date Issued: 2018
- Authors: Stander, Rizel
- Date: 2018
- Subjects: Employee motivation , Employees -- Attitudes Organizational change Reengineering (Management)
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/35278 , vital:33690
- Description: Mayo (2016, p. 88) states that many researchers agree that investing in employee engagement has guaranteed great returns; the question for organisations are whether these returns will be linear or exponential for them. A new breed of company emerged called the “exponential organisation” which leverage accelerating technologies to achieve an unheard-of business model that shows exponential growth. However, this technology is still created, maintained and reinvented by employees. Therefore, the premise is that highly engaged employees are one of the key factors that fuel exponential organisations, and this was under investigation in this research study. Employee engagement has been extensively researched yet only a few organisations can claim the majority of their employees are highly engaged. The topic of employee engagement within exponential organisations, however, has barely been covered by scholars or practitioners. Subsequently, given that it is a new organisational phenomenon, little academic or practitioner’s research could be found. For this reason, the main purpose of this study was to find key drivers of employee engagement within exponential organisations to develop a theoretical framework and hypotheses which could be statistically tested. The outcomes could assist in enhancing employee engagement within exponential organisations, thereby achieving greater business success. An online survey questionnaire was used to gather empirical data within a financial technology exponential organisation. The sample consisted of 40 fulltime employees working in Australia, China and South Africa of which most were between the ages of 35 to 44 years old and have been with the organisation for less than two years. The results showed that organisational management and employee autonomy were found to have a direct positive relationship with the concept of employee engagement and is found to be key drivers of employee engagement within exponential organisations.
- Full Text:
- Date Issued: 2018
Enhancing parental involvement in children’s academic work: Implications for teaching and learning
- Authors: Fihla, Gcobisa Victoria
- Date: 2018
- Subjects: Education -- Parent participation Parent-teacher relationships Academic achievement
- Language: English
- Type: Thesis , Doctoral , PhD (Education)
- Identifier: http://hdl.handle.net/10353/8042 , vital:31485
- Description: Partnership between schools and parents seems to substandard, leading to both parties questioning each other on why children underperform. Most parents view the school as an instrument for the achievement of children and parents with limited or no education may have little or no interest in supporting children’s academic work. The aim of this study was to investigate how parental involvement in children’s academic work can be enhanced. It focused on three rural secondary schools in the Amathole West Education District in the Eastern Cape Province of South Africa. The study particularly investigated how school schools involved parents in children’s academic work and how they, together with principals, teachers and learners view their involvement in children’s academic work. Guided by Epstein’s theory of parental involvement, this qualitative study was premised on the interpretative paradigm. Face to face interviews and focus group discussions were used to collect data from three high schools in the Amathole West Education District. Purposive sampling was used to select participants who comprised a target population of 24 participants. It emerged from the data that although schools were trying to involve parents in children’s academic work, their activities were uncoordinated, occurred at school level rather than classroom level and focused less on learners’ academic work. Parent’ involvement in their children’s academic work was not touching the real curriculum issues; rather it touched on the outside. The data also showed that parents’ academic statuses influenced their participation as those who had little education seemed to be reluctant to participate on academic issues. The study concludes that there was lack of coordinated strategies by schools to involve parents in children’s academic work. The study, therefore, recommends that Coordinated Grade-based Parent-Teacher Forums be established. This will assist in opening a planform for teachers and parents to engage on teaching and learning discussions and curriculum debates.
- Full Text:
- Date Issued: 2018
- Authors: Fihla, Gcobisa Victoria
- Date: 2018
- Subjects: Education -- Parent participation Parent-teacher relationships Academic achievement
- Language: English
- Type: Thesis , Doctoral , PhD (Education)
- Identifier: http://hdl.handle.net/10353/8042 , vital:31485
- Description: Partnership between schools and parents seems to substandard, leading to both parties questioning each other on why children underperform. Most parents view the school as an instrument for the achievement of children and parents with limited or no education may have little or no interest in supporting children’s academic work. The aim of this study was to investigate how parental involvement in children’s academic work can be enhanced. It focused on three rural secondary schools in the Amathole West Education District in the Eastern Cape Province of South Africa. The study particularly investigated how school schools involved parents in children’s academic work and how they, together with principals, teachers and learners view their involvement in children’s academic work. Guided by Epstein’s theory of parental involvement, this qualitative study was premised on the interpretative paradigm. Face to face interviews and focus group discussions were used to collect data from three high schools in the Amathole West Education District. Purposive sampling was used to select participants who comprised a target population of 24 participants. It emerged from the data that although schools were trying to involve parents in children’s academic work, their activities were uncoordinated, occurred at school level rather than classroom level and focused less on learners’ academic work. Parent’ involvement in their children’s academic work was not touching the real curriculum issues; rather it touched on the outside. The data also showed that parents’ academic statuses influenced their participation as those who had little education seemed to be reluctant to participate on academic issues. The study concludes that there was lack of coordinated strategies by schools to involve parents in children’s academic work. The study, therefore, recommends that Coordinated Grade-based Parent-Teacher Forums be established. This will assist in opening a planform for teachers and parents to engage on teaching and learning discussions and curriculum debates.
- Full Text:
- Date Issued: 2018
Environmental health community service in the Eastern Cape Province, South Africa
- Authors: Mbola, Patience
- Date: 2018
- Subjects: Environmental health -- South Africa -- Eastern Cape , Environmental health -- Administration -- South Africa -- Eastern Cape Environmental health -- Evaluation -- South Africa -- Eastern Cape Community health services -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/32028 , vital:31920
- Description: In terms of the Health Professions Act (Act 56 of 1974), Environmental Health graduates are required to conduct a year of Community Service before they are allowed to register as independent Environmental Health Practitioners at the Health Professions Council of South Africa. The main purpose of Community Service by these graduates is to assist Environmental Health Practitioners in the execution of their daily tasks, thereby contributing to more effective service delivery, especially to the disadvantaged communities, within the sphere of government where they are deployed. Several studies have been conducted in an effort to identify problem areas in other health care professions during the Community Service year, but no such study could be found on Environmental Health. The aim of this study was to do the same for the Environmental Health profession in South Africa, by focusing on problems and challenges during Community Service placement, specifically the 2013 to 2016 intakes of Community Service practitioners in the Eastern Cape Province and the administrators responsible for the program at national, provincial and municipal spheres of government. The study employed both quantitative and qualitative research designs (mixed method) and was by nature explorative, descriptive and contextual. Two populations were involved; namely, twenty four Environmental Health graduates who completed their Community Service during 2013 to 2016 within the Eastern Cape Province, and ten Environmental Health Practitioners who were responsible for the administration of the Community Service program at the provincial and municipal spheres of government during the same period. A purposive sample was drawn from each population. Qualitative data was collected by means of interviews and quantitative data through questionnaires. Qualitative data was analysed using Tech’s method of data analysis and quantitative data was statistically analysed. The results of the study revealed that the Eastern Cape Department of Health needs to review the Community Service program for Environmental Health graduates and further initiate resolutions in terms of the identified problems, such as maladministration of Community Service which related to the lack of consistency of communication during the organisation of the Community Service program; declined/decreasing number of Environmental Health Community Service posts in the Eastern Cape Province which led to a shortage of human resources; Inadequate provision of material resources for Community Service; lack of induction training and inconsistent supervision of Environmental Health Community Service practitioners; and lack of evaluation of the success of the Environmental Health Community Service program. The study findings suggest important inequalities and non-compliances which should deserve urgent attention. Based on the challenges that have been identified regarding the organisation and implementation of the Community Service program, this study concludes by presenting recommendations for the improvement of the Community Service program in the Environmental Health profession.
- Full Text:
- Date Issued: 2018
- Authors: Mbola, Patience
- Date: 2018
- Subjects: Environmental health -- South Africa -- Eastern Cape , Environmental health -- Administration -- South Africa -- Eastern Cape Environmental health -- Evaluation -- South Africa -- Eastern Cape Community health services -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/32028 , vital:31920
- Description: In terms of the Health Professions Act (Act 56 of 1974), Environmental Health graduates are required to conduct a year of Community Service before they are allowed to register as independent Environmental Health Practitioners at the Health Professions Council of South Africa. The main purpose of Community Service by these graduates is to assist Environmental Health Practitioners in the execution of their daily tasks, thereby contributing to more effective service delivery, especially to the disadvantaged communities, within the sphere of government where they are deployed. Several studies have been conducted in an effort to identify problem areas in other health care professions during the Community Service year, but no such study could be found on Environmental Health. The aim of this study was to do the same for the Environmental Health profession in South Africa, by focusing on problems and challenges during Community Service placement, specifically the 2013 to 2016 intakes of Community Service practitioners in the Eastern Cape Province and the administrators responsible for the program at national, provincial and municipal spheres of government. The study employed both quantitative and qualitative research designs (mixed method) and was by nature explorative, descriptive and contextual. Two populations were involved; namely, twenty four Environmental Health graduates who completed their Community Service during 2013 to 2016 within the Eastern Cape Province, and ten Environmental Health Practitioners who were responsible for the administration of the Community Service program at the provincial and municipal spheres of government during the same period. A purposive sample was drawn from each population. Qualitative data was collected by means of interviews and quantitative data through questionnaires. Qualitative data was analysed using Tech’s method of data analysis and quantitative data was statistically analysed. The results of the study revealed that the Eastern Cape Department of Health needs to review the Community Service program for Environmental Health graduates and further initiate resolutions in terms of the identified problems, such as maladministration of Community Service which related to the lack of consistency of communication during the organisation of the Community Service program; declined/decreasing number of Environmental Health Community Service posts in the Eastern Cape Province which led to a shortage of human resources; Inadequate provision of material resources for Community Service; lack of induction training and inconsistent supervision of Environmental Health Community Service practitioners; and lack of evaluation of the success of the Environmental Health Community Service program. The study findings suggest important inequalities and non-compliances which should deserve urgent attention. Based on the challenges that have been identified regarding the organisation and implementation of the Community Service program, this study concludes by presenting recommendations for the improvement of the Community Service program in the Environmental Health profession.
- Full Text:
- Date Issued: 2018
Environmental management of wetlands on an urban periphery: the case of Bay West
- Authors: Domoney, Nicola Leah
- Date: 2018
- Subjects: Wetland management -- South Africa -- Nelson Mandela Bay Municipality , Remote sensing Chlorophyll
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/30854 , vital:31183
- Description: South Africa is a semi-arid country and thus depends on sound management of its water resources. Wetlands, despite their importance to water resource storage and water quality, among their other ecological and social significance, remain the most threatened of South Africa’s ecosystems. One of their greatest threats is encroachment by urbanisation. This occurs because wetlands, and especially ephemeral urban periphery wetlands, are overlooked. This study’s main objective was to determine the water quality and health of the wetlands adjacent to the newly established Bay West development on the western urban periphery of Nelson Mandela Bay. Wetlands are difficult to access and it is time-consuming to assess them. Remote sensing, however, overcomes this challenge and is cost-effective and time-considerate. It was the aim of this study to assess the health of the peri-urban wetlands on the Bay West periphery in order to formulate an appropriate environmental management plan, and remote sensing was tested as an effective method for wetland health management. It was found that the wetlands closer to the urban residential area (Sherwood suburb) were far more impacted than the wetlands nearer to Bay West Mall. Wetlands Six to Eight were higher in all parameters of pH, total dissolved solutes (TDS), salinity, conductivity and chlorophyll a concentration than Wetlands One to Five located further away from the urban area. A correlation with distance away from the urban area found a strong inverse relationship with between distance and the water quality factor, yielding a correlation coefficient of (<-0.7) in 2017 and (<-0.9) in 2018 with regard to TDS, salinity and conductivity. This, therefore, suggests that the wetlands’ health deteriorates towards the urban area. TDS, salinity, pH and conductivity correlate highly with chlorophyll a concentration at (>0.70). There was significant difference in pH in the year 2017 between the Bay West wetlands and the reference wetland (p<0.05; df=19; f= 3.56; n=3) and in 2018 (p<0.01; df=22; f= 8.90; n=3). No significant difference was found between the wetlands for dissolved oxygen. TDS between the wetlands was found to be significantly different in the year 2017 (p<0.01; df=23; f= 44.16; n=3) and 2018 (p<0.05; df=22; f=2.62; n=3), where conductivity and salinity returned the same p value for 2017 and 2018 as TDS respectively. There was a significant difference in chlorophyll a between the Bay West wetlands in 2017 (p<0.05; df=20; f=3.29; n=3) and Wetland Seven measured eutrophic at 22.45 mg/L-1. Remote sensing red band values and the field sample absorption values were highly correlated at R2= 0.5. Chlorophyll a content of wetland water correlated with NDVI data at R2= 0.6. Thus, remote sensing proved to be a successful estimator for wetlands health analysis and a proxy for wetland management. These results yielded an environmental management plan where monitoring water quality via chlorophyll a indicated health levels of the wetlands via trophic state.
- Full Text:
- Date Issued: 2018
- Authors: Domoney, Nicola Leah
- Date: 2018
- Subjects: Wetland management -- South Africa -- Nelson Mandela Bay Municipality , Remote sensing Chlorophyll
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/30854 , vital:31183
- Description: South Africa is a semi-arid country and thus depends on sound management of its water resources. Wetlands, despite their importance to water resource storage and water quality, among their other ecological and social significance, remain the most threatened of South Africa’s ecosystems. One of their greatest threats is encroachment by urbanisation. This occurs because wetlands, and especially ephemeral urban periphery wetlands, are overlooked. This study’s main objective was to determine the water quality and health of the wetlands adjacent to the newly established Bay West development on the western urban periphery of Nelson Mandela Bay. Wetlands are difficult to access and it is time-consuming to assess them. Remote sensing, however, overcomes this challenge and is cost-effective and time-considerate. It was the aim of this study to assess the health of the peri-urban wetlands on the Bay West periphery in order to formulate an appropriate environmental management plan, and remote sensing was tested as an effective method for wetland health management. It was found that the wetlands closer to the urban residential area (Sherwood suburb) were far more impacted than the wetlands nearer to Bay West Mall. Wetlands Six to Eight were higher in all parameters of pH, total dissolved solutes (TDS), salinity, conductivity and chlorophyll a concentration than Wetlands One to Five located further away from the urban area. A correlation with distance away from the urban area found a strong inverse relationship with between distance and the water quality factor, yielding a correlation coefficient of (<-0.7) in 2017 and (<-0.9) in 2018 with regard to TDS, salinity and conductivity. This, therefore, suggests that the wetlands’ health deteriorates towards the urban area. TDS, salinity, pH and conductivity correlate highly with chlorophyll a concentration at (>0.70). There was significant difference in pH in the year 2017 between the Bay West wetlands and the reference wetland (p<0.05; df=19; f= 3.56; n=3) and in 2018 (p<0.01; df=22; f= 8.90; n=3). No significant difference was found between the wetlands for dissolved oxygen. TDS between the wetlands was found to be significantly different in the year 2017 (p<0.01; df=23; f= 44.16; n=3) and 2018 (p<0.05; df=22; f=2.62; n=3), where conductivity and salinity returned the same p value for 2017 and 2018 as TDS respectively. There was a significant difference in chlorophyll a between the Bay West wetlands in 2017 (p<0.05; df=20; f=3.29; n=3) and Wetland Seven measured eutrophic at 22.45 mg/L-1. Remote sensing red band values and the field sample absorption values were highly correlated at R2= 0.5. Chlorophyll a content of wetland water correlated with NDVI data at R2= 0.6. Thus, remote sensing proved to be a successful estimator for wetlands health analysis and a proxy for wetland management. These results yielded an environmental management plan where monitoring water quality via chlorophyll a indicated health levels of the wetlands via trophic state.
- Full Text:
- Date Issued: 2018